Environmentally friendly recycling system and method for cement chlorine bypass dust

Abstract

To provide an environment-friendly recycling system and a method for preventing scale in a pipe when recycling chlorine bypass dust as a by-product of a cement process, and for dissolving or dehydrating the dust in one or more partial repeating steps and continuous circulation steps.SOLUTION: A recycling system comprises one or more dissolution agitators in which the cement chlorine bypass dust is charged and the cement chlorine bypass dust is dissolved in at least one of water, an acidic aqueous solution, and a sedimentation tank supernatant liquid of a potassium chloride precipitation tank to form a slurry; a slurry dehydrator that separates slurry dissolved by the dissolution agitator into a sludge cake and a dehydration filtrate; and one or more potassium chloride precipitation tanks in which the dehydration filtrate is transferred and the potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals. When the slurry is transferred from the dissolution agitator to the slurry dehydrator, the slurry is pumped by a roller vacuum type self-sucking hose pump.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an environmentally friendly recycling system and method for cement chlorine bypass dust, which prevents scale formation in piping when recycling chlorine bypass dust, a by-product of the cement process, and the dissolution or dehydration process is carried out in one or more partial repeat steps and a continuous circulation step. [Background technology]

[0002] Chlorine bypass dust is a process by-product that typically contains potassium chloride (KCl), quicklime (CaO) or anhydrite (CaSO4) that is left over from bypassing the cement production process, adding some of the chlorine components that can cause problems such as clogging of preheaters.

[0003] In particular, chlorine bypass dust is an inorganic substance contained in hot gas that is forcibly extracted at temperatures of around 1,000°C from the kiln in order to remove volatile substances including chlorine to ensure smooth operation of the clinker production kiln, which operates at a high temperature of around 2,000°C in cement production plants. In addition to potassium chloride, it contains anhydrous gypsum and quicklime that have already been dehydrated and decarbonated at the high temperature of 1,000°C.

[0004] Chlorine bypass dust generated in cement plants is a designated waste containing high amounts of alkali, especially potassium, chlorine, and heavy metals. In most cases, however, it has simply been landfilled. However, in recent years, due to the increase in landfill costs, research has begun on a cost-saving measure, such as establishing a separate recycling process within the cement plant to recover potassium chloride and use the sludge as a cement raw material, and on the application of this method to actual processes.

[0005] The above-mentioned recycling methods are mainly aimed at recovering potassium chloride to produce recycled products, improving the purity of calcium chloride, increasing the yield, reducing heavy metals or reducing recovery costs, and developing recycling processes and improving technologies for treating sludge to be used as a cement raw material, and have not been commercially widespread.

[0006] Furthermore, the above recycling methods have the following fatal drawbacks.

[0007] First, the above recycling method has a drawback in that partial steps are repeated and the entire process cannot be operated continuously.

[0008] In other words, in the upstream process, a dissolution process using water or an acidic aqueous solution must be carried out first, and the dissolved chlorine bypass dust or a sludge state with a moisture content of about 60% is transported to the downstream process, such as separation, dehydration, and drying.

[0009] At this time, depending on the condition of the material to be transported, it is transported by belt conveyor or by pressure-feeding by pump through piping.

[0010] However, chlorine bypass dust is an inorganic substance contained in hot gas that is forcibly extracted at a temperature of about 1,000℃ in the kiln to remove volatile substances including chlorine for smooth operation of the clinker manufacturing kiln, which is operated at a high temperature of about 2,000℃ in the cement manufacturing plant. It contains not only a large amount of alkali and chlorine, but also calcium (Ca) and sulfuric acid (SO4 2- ) ions, and when it comes into contact with water or an acidic aqueous solution, not only potassium chloride (KCl) but also calcium carbonate (CaCO3) and gypsum (CaSO4) are generated during transportation on a belt conveyor or pumping through a piping pump. As a result, scale is inevitably generated on the belt conveyor or piping, and partial loading or clogging of the transported material makes it impossible to repeat some essential processes or to operate the entire process continuously for a certain period of time. This leads to problems such as a limit to the increase in potassium chloride yield and an increase in process operation costs, which not only reduces economic efficiency but also restricts basic facility operation.

[0011] Second, the above recycling methods have a drawback in that they are unable to add value to the sludge.

[0012] That is, sludge with a moisture content of about 60% is generated by dissolving chlorine bypass dust in water or an acidic aqueous solution, and then separation and dehydration are performed. However, potassium chloride, calcium carbonate and gypsum scale inevitably form on the conveyor belts and piping during the process transfer, and some essential processes cannot be repeated or operated continuously due to partial loading or clogging. Therefore, it is impossible to remove the chlorine content contained in the sludge below a certain level, and the sludge is simply fed back into the cement kiln as a cheap cement raw material, with limited recycling to create high added value.

[0013] Third, the above recycling methods have a drawback in that they cause problems in the generation and treatment of wastewater.

[0014] In the processes of dissolving chlorine bypass dust in water or an acidic aqueous solution, separating, dehydrating, drying, etc., wastewater is inevitably generated in the form of a dissolution liquid or sludge with a water content of about 60%. Depending on the amount of wastewater generated, this can lead to waste disposal, purification treatment, drying and evaporation, etc., but this is undesirable from the viewpoint of operation and economy due to the costs of waste disposal, purification treatment chemicals, electricity for drying, LNG, etc.

[0015] Fourth, the above recycling method has a drawback in that the drying efficiency is reduced.

[0016] In other words, because conventional dryers such as existing rotary dryers and spray dryers are mainly used, there is a problem of reduced economic viability due to excessive energy costs for drying electricity and LNG, etc., caused by reduced drying efficiency.

[0017] Therefore, the applicant has made a long and arduous effort to solve the problems of partial process repetition, inability to operate the whole process continuously, inability to add value to sludge, generation and treatment of wastewater, and reduced drying efficiency, and has developed an environmentally friendly recycling system and method for cement chlorine bypass dust, which prevents scale formation in piping and performs dissolution or dehydration processes through one or more partial repetition processes and continuous circulation processes when recycling chlorine bypass dust, a by-product of the cement process, and has completed the present invention. [Prior art documents] [Patent documents]

[0018] Korean Patent No. 10-1561637 (Patent registration date: October 13, 2015) Summary of the Invention [Problem to be solved by the invention]

[0019] Therefore, an object of the present invention is to provide an environmentally friendly recycling system for cement chlorine bypass dust, which prevents the formation of scale in piping when recycling chlorine bypass dust, which is a by-product of the cement process, and in which the dissolution or dehydration process is carried out by one or more partial repeat processes and a continuous circulation process.

[0020] Another object of the present invention is to provide an environmentally friendly recycling method for cement chlorine bypass dust, which is a by-product of the cement process, and which prevents the formation of scale in piping and performs the dissolution or dehydration process by one or more partial repeat steps and a continuous circulation step when recycling the chlorine bypass dust.

[0021] Another object of the present invention is to provide potassium chloride recovered by the above-mentioned environmentally friendly recycling system of cement chlorine bypass dust.

[0022] Another object of the present invention is to provide a sludge having a reduced chlorine concentration, which is produced by the above-mentioned environmentally friendly recycling system for cement chlorine bypass dust.

[0023] Another object of the present invention is to provide potassium chloride recovered by the above-mentioned recycling method of cement chlorine bypass dust, which is environmentally friendly.

[0024] Another object of the present invention is to provide a sludge having a reduced chlorine concentration produced by the above-mentioned environmentally friendly recycling method of cement chlorine bypass dust.

[0025] The problems that the present invention is intended to solve are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0026] In order to solve the above problems, according to one aspect of the present invention, An environmentally friendly recycling system for cement chlorine bypass dust, comprising: one or more dissolving agitators 120 into which the cement chlorine bypass dust is introduced and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry; a slurry dewatering device 130 for separating the slurry dissolved in the dissolving agitator into a sludge cake and a dewatered filtrate; and one or more potassium chloride settling tanks 160 into which the dewatered filtrate is transferred and where potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals; When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, The environmentally friendly recycling system for cement chlorine bypass dust is characterized in that the formation of scale in the piping is prevented by pumping with the roller vacuum type self-priming hose pump, and the dissolving or dehydrating process is performed in one or more partial repeating steps or in a continuous circulation step. To provide an environmentally friendly recycling system for cement chlorine bypass dust.

[0027] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: a sludge cake storage area 140 to which the sludge cake is transferred; one or more sludge cake dryers 150 for drying sludge cake in the sludge cake storage area to form a reduced-chlorine sludge for use as a cement feedstock; one or more potassium chloride dryers 170, in which the dewatered filtrate is dried to recover potassium chloride; or The method may further include one or more potassium chloride dryers 170, into which the precipitate precipitated in the potassium chloride precipitation tank 160 is transported and dried to recover potassium chloride.

[0028] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: The one or more dissolving agitators 120 are installed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolution agitators 120; The one or more dissolving agitators 120 may further receive dryer condensate from the potassium chloride dryer 170, and the cement chlorine bypass dust may be dissolved in the dryer condensate from the potassium chloride dryer 170.

[0029] According to one embodiment of the present invention, the sludge cake storage area 140 is The dewatered sludge cake can be dropped, stored or transported to a storage area below the side of the dewaterer 130 by undergrounding the storage area below the side of the dewaterer.

[0030] According to one embodiment of the present invention, the sludge cake storage area 140 is At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is input into the sludge cake storage area 140, The sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to prepare a slurry, which can be pumped and transported to the dissolving and mixing machine 120 by the roller vacuum type self-priming hose pump.

[0031] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: As a first dissolution, in the No. 1 dissolving mixer 120, the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; As a first dehydration step, the slurry is dehydrated by the slurry dehydrator 130 to produce a first sludge cake, which is then dropped into the sludge cake storage area, and the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a first regenerated slurry; a step of pumping the first regenerated slurry to the No. 2 dissolving and mixing machine 120 using a roller vacuum type self-priming hose pump; As a second dissolution, the first regenerated slurry transferred to the second dissolving mixer 120 is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; and In the second dehydration, the slurry is dehydrated by the slurry dehydrator 130 to produce a second sludge cake, which is then dropped into the sludge cake storage area 140, and the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a second regenerated slurry; The cement chlorine bypass dust can be recycled in an environmentally friendly manner by preventing the formation of scale in the piping, and the dissolving or dehydrating process can be carried out in one or more partial repeating steps and a continuous circulating step.

[0032] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: When the dissolving or dehydrating step is carried out in one or more partial repeat steps and a continuous circulation step, The more times the lysis or dehydration steps are repeated, the shorter the lysis time may be.

[0033] According to one embodiment of the present invention, the potassium chloride precipitation tank 160 may be equipped with a constant or occasional heating device such as a hot wire or steam line at the bottom and sides.

[0034] According to an embodiment of the present invention, a flocculant may be added to the potassium chloride settling tank 160, The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The organic polymeric compounds may include starches or polyacrylamides and their derivatives.

[0035] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: In order to shorten the time required for potassium chloride crystal precipitation in the potassium chloride precipitation tank 160, When the precipitation and settling of potassium chloride crystals occurs in the dehydrated filtrate transferred to the potassium chloride precipitation tank 160 and a supernatant liquid is generated in the precipitation tank, the supernatant liquid in the potassium chloride precipitation tank 160 is pumped and transferred using a roller vacuum type self-priming hose pump or a submersible pump, and can be used as mixed water for dissolution in the dissolving mixer 120.

[0036] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: To completely eliminate wastewater generation, The condensed water of the sludge cake dryer 150 or the condensed water of the potassium chloride dryer 170 can be transported and used as the mixed water for dissolving in the dissolving mixer 120 and the mixed water for producing regenerated slurry for the sludge cake in the sludge cake storage site 140.

[0037] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: During the repeated process of separating the sludge from water or an aqueous solution and dehydrating it, the sludge cake generated in the slurry dehydrator is transported to an underground storage area below the side of the slurry dehydrator. The subsequent transfer line further comprises two lines, a sludge cake dryer 150 and a product sludge storage area 180, and the sludge cake can be transported separately or simultaneously.

[0038] According to one embodiment of the present invention, the environmentally friendly recycling system for cement chlorine bypass dust comprises: The sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or aqueous solution and dehydrating it is transferred to an underground storage area under the side of the slurry dehydrator, and then transferred to a sludge cake dryer where the moisture content is reduced to 5% or less, enabling it to be produced into high-value-added dried sludge for use as a cement auxiliary material.

[0039] According to another aspect of the present invention, 1. An environmentally friendly method for recycling cement chlorine bypass dust, comprising: The cement chlorine bypass dust is introduced into one or more dissolving agitators 120, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry (S110); The slurry dissolved in the dissolving mixer 120 is transferred to the slurry dewatering machine 130 and separated into a sludge cake and a dewatered filtrate (S120); The dehydrated filtrate is transferred to one or more of the potassium chloride precipitation tanks 160 to recover potassium chloride by precipitation and sedimentation of potassium chloride crystals (S130); When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, The environmentally friendly recycling method for the cement chlorine bypass dust is characterized in that the cement chlorine bypass dust is pumped by the roller vacuum type self-priming hose pump to prevent scale formation in the piping, and the dissolving or dehydrating process is carried out in one or more partial repeating steps or in a continuous circulation step. It is possible to provide an environmentally friendly recycling method for cement chlorine bypass dust.

[0040] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: The dehydrated filtrate separated in the slurry dehydrator 130 is transferred to one or more potassium chloride dryers 170 for drying and recovering potassium chloride (S140); or The method may further include a step of transferring the precipitate from the potassium chloride precipitation tank 160 to one or more potassium chloride dryers 170 for drying and recovering potassium chloride (S150).

[0041] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: The sludge cake is transferred to a sludge cake storage site 140 and processed into sludge for use as a calciner raw material (S160); or The method may further include a step (S170) of transferring the sludge cake to a sludge cake dryer 150 to manufacture dried sludge for use as a cement auxiliary material.

[0042] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: A step (S180) of feeding the supernatant of the potassium chloride precipitation tank 160 or the condensed water of the potassium chloride dryer 170 into the dissolving mixer 120 together with water or an acidic aqueous solution; or The method may further include a step (S190) of: inputting the dryer condensate of the potassium chloride dryer 170 or the dryer condensate of the sludge cake dryer 150 into a sludge cake storage site 140; inputting at least one selected from water, an acidic aqueous solution, the condensate of the sludge cake dryer 150, and the condensate of the potassium chloride dryer 170 into the sludge cake in the sludge cake storage site 140 to prepare a regenerated slurry; and then transferring the regenerated slurry to the dissolving mixer 120.

[0043] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: The one or more dissolving agitators 120 are installed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolution agitators 120; Dryer condensate of a potassium chloride dryer 170 is further input to the one or more dissolving agitators 120, so that the cement chlorine bypass dust can be dissolved in the dryer condensate of the potassium chloride dryer 170.

[0044] According to an embodiment of the present invention, a flocculant may be added to the potassium chloride settling tank 160, The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The organic polymeric compound may include starches, polyacrylamides, or derivatives thereof.

[0045] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: In order to shorten the time required for potassium chloride crystal precipitation in the potassium chloride precipitation tank 160, When the precipitation and settling of potassium chloride crystals occurs in the dehydrated filtrate transferred to the potassium chloride precipitation tank 160 and a supernatant liquid is generated in the precipitation tank, the supernatant liquid in the potassium chloride precipitation tank 160 is pumped and transferred using a roller vacuum type self-priming hose pump or a submersible pump, and can be used as mixed water for dissolution in the dissolving mixer 120.

[0046] According to one embodiment of the present invention, the sludge cake storage area 140 is The dewatered sludge cake can be dropped, stored or transported to a storage area below the side of the dewaterer 130 by undergrounding the storage area below the side of the dewaterer.

[0047] According to one embodiment of the present invention, the sludge cake storage area 140 is At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is input into the sludge cake storage area 140, The sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to prepare a slurry, which can be pumped and transported to the dissolving and mixing machine 120 by the roller vacuum type self-priming hose pump.

[0048] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: As a first dissolution, in the No. 1 dissolving mixer 120, the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; As a first dehydration step, the slurry is dehydrated by the slurry dehydrator 130 to produce a first sludge cake, which is then dropped into the sludge cake storage area, and the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a first regenerated slurry; a step of pumping the first regenerated slurry to the No. 2 dissolving and mixing machine 120 using a roller vacuum type self-priming hose pump; As a second dissolution, the first regenerated slurry transferred to the second dissolving mixer 120 is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; and In the second dehydration, the slurry is dehydrated by the slurry dehydrator 130 to produce a second sludge cake, which is then dropped into the sludge cake storage area 140, and the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a second regenerated slurry; It is possible to prevent the formation of scale inside the piping, and to carry out the dissolving or dehydrating process by one or more partial repeating steps and a continuous circulation step.

[0049] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: When the dissolving or dehydrating step is carried out in one or more partial repeat steps and a continuous circulation step, The more times the lysis or dehydration steps are repeated, the shorter the lysis time may be.

[0050] According to one embodiment of the present invention, the potassium chloride precipitation tank 160 may be equipped with a constant or occasional heating device such as a hot wire or steam line at the bottom and sides.

[0051] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: To completely eliminate wastewater generation, The condensed water of the sludge cake dryer 150 or the condensed water of the potassium chloride dryer 170 can be transported and used as the mixed water for dissolving in the dissolving mixer 120 and the mixed water for producing regenerated slurry for the sludge cake in the sludge cake storage site 140.

[0052] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: During the repeated process of separating the sludge from water or an aqueous solution and dehydrating it, the sludge cake generated in the slurry dehydrator is transported to an underground storage area below the side of the slurry dehydrator. The subsequent transfer line further comprises two lines, a sludge cake dryer 150 and a product sludge storage area 180, and the two can be transported separately or simultaneously.

[0053] According to one embodiment of the present invention, the method for recycling the cement chlorine bypass dust in an environmentally friendly manner includes: The sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or aqueous solution and dehydrating it is transferred to an underground storage area under the side of the slurry dehydrator, and then transferred to a sludge cake dryer where the moisture content is reduced to 5% or less, enabling it to be produced into high-value-added dried sludge for use as a cement auxiliary material.

[0054] According to another aspect of the present invention, there is provided potassium chloride recovered by the above-mentioned environmentally friendly recycling system for cement chlorine bypass dust.

[0055] According to another aspect of the present invention, there is provided a sludge having a reduced chlorine concentration produced by the above-mentioned environmentally friendly recycling system for cement chlorine bypass dust.

[0056] According to another aspect of the present invention, there is provided potassium chloride recovered by the above-mentioned environmentally friendly recycling method of cement chlorine bypass dust.

[0057] According to another aspect of the present invention, there is provided a sludge having a reduced chlorine concentration produced by the above-mentioned environmentally friendly recycling method of cement chlorine bypass dust. Effect of the Invention

[0058] According to the present invention, when recycling chlorine bypass dust, which is a by-product of the cement process, the formation of scale in the piping is prevented, and the dissolution or dehydration process is carried out as one or more partial repeat processes or a continuous circulation process, thereby providing an environmentally friendly recycling system for cement chlorine bypass dust, and thus the recycling efficiency is excellent.

[0059] In addition, the present invention provides an environmentally friendly recycling method for cement chlorine bypass dust, which is a by-product of the cement process, by preventing the formation of scale in the piping and performing the dissolving or dehydrating process in one or more partial repeat processes or in a continuous circulation process, thereby providing a highly stable and economical process.

[0060] In addition, the present invention provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling system, which is economical.

[0061] In addition, the present invention provides a sludge with a reduced chlorine concentration produced by the environmentally friendly recycling system of the cement chlorine bypass dust, which is economical.

[0062] In addition, the present invention provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling method, which is economical.

[0063] The present invention is also economical since it provides a sludge with a reduced chlorine concentration produced by the environmentally friendly recycling method of the cement chlorine bypass dust.

[0064] It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be inferred from the configuration of the invention described in the detailed description of the present invention or the claims. [Brief description of the drawings]

[0065] [Figure 1] FIG. 1 is a schematic block diagram of an environmentally friendly recycling system for cement chlorine bypass dust according to one embodiment of the present invention. [Diagram 2] 1 is a process flow diagram of an environmentally friendly recycling method for cement chlorine bypass dust according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0066] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0067] The advantages and features of the present invention, as well as the method for achieving the same, will become apparent from the following detailed description of the embodiments in conjunction with the accompanying drawings.

[0068] However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various different forms, however, the embodiments are provided to complete the disclosure of the present invention and fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0069] Furthermore, in describing the present invention, if it is determined that related known techniques may obscure the gist of the present invention, detailed description thereof will be omitted.

[0070] The present invention will be described in detail below.

[0071] [Environmentally friendly recycling system for cement chlorine bypass dust] The present invention provides an environmentally friendly recycling system for cement chlorine bypass dust, which prevents the formation of scale in piping when recycling chlorine bypass dust, a by-product of the cement process, and performs the dissolution or dehydration process by one or more partial repeat processes and a continuous circulation process.

[0072] The present invention provides an environmentally friendly recycling system for cement chlorine bypass dust, comprising: one or more dissolving agitators 120 into which the cement chlorine bypass dust is introduced and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry; a slurry dewatering device 130 for separating the slurry dissolved in the dissolving agitator into a sludge cake and a dewatered filtrate; and one or more potassium chloride settling tanks 160 into which the dewatered filtrate is transferred and where potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals; When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, The environmentally friendly recycling system for cement chlorine bypass dust prevents scale formation in the piping by pumping with the roller vacuum type self-priming hose pump, and the dissolution or dehydration process can be carried out in one or more partial repeat processes or a continuous circulation process.

[0073] The present invention provides an environmentally friendly recycling system for cement chlorine bypass dust, which is a by-product of the cement process, by preventing the formation of scale in piping and performing the dissolution or dehydration process as one or more partial repeat processes or a continuous circulation process, thereby achieving excellent recycling efficiency.

[0074] And, the environmentally friendly recycling system of the cement chlorine bypass dust comprises: a sludge cake storage area 140 to which the sludge cake is transferred; one or more sludge cake dryers 150 for drying sludge cake in the sludge cake storage area to form a reduced-chlorine sludge for use as a cement feedstock; one or more potassium chloride dryers 170, in which the dewatered filtrate is dried to recover potassium chloride; or The method may further include one or more potassium chloride dryers 170, into which the precipitate precipitated in the potassium chloride precipitation tank 160 is transported and dried to recover potassium chloride.

[0075] Chlorine bypass dust is a process by-product that typically contains potassium chloride (KCl), quicklime (CaO) or anhydrite (CaSO4) that is left over from bypassing the cement production process, adding some of the chlorine components that can cause problems such as clogging of preheaters.

[0076] In particular, chlorine bypass dust is an inorganic substance contained in hot gas that is forcibly extracted at temperatures of around 1,000°C from the kiln in order to remove volatile substances including chlorine to ensure smooth operation of the clinker production kiln, which operates at a high temperature of around 2,000°C in cement production plants. In addition to potassium chloride, it contains anhydrous gypsum and quicklime that have already been dehydrated and decarbonated at the high temperature of 1,000°C.

[0077] Chlorine bypass dust generated in cement plants is designated waste with high contents of alkali, especially potassium, chlorine, heavy metals, etc., and has been almost always simply landfilled. However, in recent years, due to the increase in landfill costs, research has begun on a cost-saving measure by establishing a separate recycling process within the cement plant to recover potassium chloride and use the sludge as a cement raw material, and the application of this method to actual processes.

[0078] The above-mentioned recycling methods are mainly aimed at recovering potassium chloride to produce recycled products, and involve the development of recycling processes and technological improvements for the purposes of improving the purity of calcium chloride, increasing the yield, reducing heavy metals or reducing recovery costs, as well as treating sludge for use as a cement raw material, and are not commercially widespread.

[0079] Furthermore, the above recycling methods have the following fatal drawbacks.

[0080] First, the above recycling method has a drawback in that it is impossible to repeat partial steps and to operate the entire process continuously.

[0081] In other words, in the upstream process, a dissolution process using water or an acidic aqueous solution must be carried out first, and the chlorine bypass dust is transported to the downstream process, such as separation, dehydration, and drying, in a dissolved state or in a sludge state with a moisture content of about 60%.

[0082] At this time, depending on the condition of the material to be transported, it is transported by belt conveyor or by pumping through piping.

[0083] However, chlorine bypass dust is an inorganic substance contained in hot gas that is forcibly extracted at a temperature of about 1,000℃ in the kiln to remove volatile substances including chlorine for smooth operation of the clinker manufacturing kiln, which is operated at a high temperature of about 2,000℃ in the cement manufacturing plant. It contains not only a large amount of alkali and chlorine, but also calcium (Ca) and sulfuric acid (SO4 2- ) ions, and when it comes into contact with water or an acidic aqueous solution, not only potassium chloride (KCl) but also calcium carbonate (CaCO3) and gypsum (CaSO4) are generated during transportation on a belt conveyor or pumping through a piping pump. As a result, scale is inevitably generated on the belt conveyor or piping, and partial loading or clogging of the transported material makes it impossible to repeat some essential processes or to operate the entire process continuously for a certain period of time or more. This leads to problems such as reduced economic efficiency due to limitations on the increase in potassium chloride yield and increased process operation costs, as well as restrictions on basic facility operation.

[0084] Second, the above recycling methods have a drawback in that they are unable to add value to the sludge.

[0085] That is, sludge with a moisture content of about 60% is generated by dissolving chlorine bypass dust in water or an acidic aqueous solution, and then separation and dehydration are performed. However, potassium chloride, calcium carbonate and gypsum scale inevitably form on the conveyor belts and piping during the process transfer, and some essential processes cannot be repeated or operated continuously due to partial loading or clogging. Therefore, the chlorine content in the sludge cannot be reduced to a certain level and is simply fed back into the cement kiln as a cheap cement raw material, with limited recycling of the sludge into high added value.

[0086] Third, the above recycling methods have a drawback in that they cause problems in the generation and treatment of wastewater.

[0087] In the processes of dissolving chlorine bypass dust in water or an acidic aqueous solution, separating, dehydrating, drying, etc., wastewater is inevitably generated when the wastewater is in a dissolved state or a sludge state with a moisture content of about 60%. Depending on the amount of wastewater generated, this can lead to waste disposal, purification treatment, drying evaporation, etc. However, from the viewpoint of operation and economy, it is undesirable due to the costs of waste disposal, purification treatment chemicals, electricity for drying, LNG, etc.

[0088] Fourth, the above recycling method has a drawback in that the drying efficiency is reduced.

[0089] In other words, because conventional dryers such as existing rotary dryers and spray dryers are mainly used, there is a problem of reduced economic viability due to excessive energy costs for drying electricity and LNG, etc., caused by reduced drying efficiency.

[0090] Therefore, the applicant has made a long and arduous effort to solve the problems of partial process repetition, inability to operate the whole process continuously, inability to add value to sludge, generation and treatment of wastewater, and reduced drying efficiency, and has developed an environmentally friendly recycling system and method for cement chlorine bypass dust, which prevents scale formation in piping and performs dissolution or dehydration processes through one or more partial repetition processes and continuous circulation processes when recycling chlorine bypass dust, a by-product of the cement process, and has completed the present invention.

[0091] FIG. 1 is a schematic block diagram of an environmentally friendly recycling system for cement chlorine bypass dust according to one embodiment of the present invention.

[0092] Referring to FIG. 1, the system includes a chlorine bypass dust storage site 100 and a chlorine bypass dust input device 110 for transporting and inputting chlorine bypass dust.

[0093] The system further includes one or more dissolving agitators 120 into which the cement chlorine bypass dust is introduced and dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a dryer condensate of the potassium chloride dryer 170 to form a slurry.

[0094] The system also includes a slurry dewatering machine 130 for separating the slurry dissolved in the dissolving mixer into a sludge cake and a dewatered filtrate, and a sludge cake storage area 140 to which the sludge cake is transferred.

[0095] and one or more sludge cake dryers 150 for drying sludge cake in the sludge cake storage area to form a reduced-chlorine sludge for use as a cement raw material.

[0096] The system also includes one or more potassium chloride precipitation tanks 160 to which the dehydrated filtrate is transferred and potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals, one or more potassium chloride dryers 170 to which the dehydrated filtrate is dried and potassium chloride is recovered, and one or more potassium chloride dryers 170 to which the sediment precipitated in the potassium chloride precipitation tanks is transferred and dried and potassium chloride is recovered.

[0097] The environmentally friendly recycling system for cement chlorine bypass dust can prevent scale formation in piping and can carry out the dissolving, dehydrating or drying process in one or more partial repeat processes or in a continuous circulation process.

[0098] Here, the one or more partial repeat steps may be 1 to 6 times.

[0099] In this case, as the number of times the partial repeat process is repeated increases, the recycling efficiency of the cement chlorine bypass dust can be increased.

[0100] The continuous circulation step may be a step in which the dissolving, dehydrating or drying step is continuously cycled one or more times.

[0101] At this time, when the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped from the upper part of the dissolving mixer 120.

[0102] In addition, the chlorine bypass dust contains not only a large amount of alkali and chlorine, but also calcium (Ca) and sulfate (SO4 2- ) ions, and when they come into contact with water or an acidic aqueous solution and are transported on a conveyor belt or pumped through a piping pump, they produce not only potassium chloride (KCl) but also calcium carbonate (CaCO3) and gypsum (CaSO4), which inevitably results in the formation of scale on the conveyor belt or piping.

[0103] Here, the roller vacuum type self-priming hose pump can discharge the slurry and regenerated slurry through the suction port and discharge port by using a high-pressure vacuum tube that expands and contracts and a compression row that can be transported in forward and reverse directions.

[0104] Therefore, the roller vacuum type self-priming hose pump fundamentally prevents partial loading or clogging of solids during transportation caused by scale formed on a belt conveyor or piping, making it possible to repeat partial or entire processes and to continuously operate the entire process for a certain period of time or more.

[0105] In addition, the sludge cake dryer 150 may include a vertical cylindrical continuous dryer.

[0106] In the vertical cylindrical continuous dryer for drying sludge cake, the entire surface of the vertical cylinder is a drying cross section, and the sludge cake introduced into the vertical cylindrical continuous dryer adheres to the entire surface of the vertical cylindrical continuous dryer in the form of a thin film by centrifugal force and dries, thereby allowing the sludge to dry in the form of a thin film.

[0107] Here, the vertical cylindrical continuous dryer for drying sludge cake has a thermal efficiency approximately one time higher than that of existing rotary dryers and spray dryers, and the evaporated steam is condensed and entirely recovered in the form of condensed water, which is subsequently used as mixed water. This means that no wastewater is generated, and the economic efficiency of the process is greatly improved.

[0108] In addition, the potassium chloride dryer 170 may include a vertical cylindrical continuous dryer.

[0109] In the vertical cylindrical continuous dryer for drying potassium chloride, the entire surface of the vertical cylinder is a drying cross section, and the sludge fed into the vertical cylindrical continuous dryer adheres to the entire surface of the vertical cylindrical continuous dryer in the form of a thin film by centrifugal force and dries, so that the sludge can be dried in the form of a thin film.

[0110] Here, the vertical cylindrical continuous dryer for drying potassium chloride has a thermal efficiency approximately one time higher than that of existing rotary dryers and spray dryers, and the evaporating steam is condensed and entirely recovered in the form of condensed water, which is subsequently used as mixed water, so that no wastewater is generated and the economic efficiency of the process is greatly improved.

[0111] And, the environmentally friendly recycling system of the cement chlorine bypass dust comprises: The one or more dissolving agitators 120 are installed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolution agitators 120; The one or more dissolving agitators 120 may further receive dryer condensate from the potassium chloride dryer 170, and the cement chlorine bypass dust may be dissolved in the dryer condensate from the potassium chloride dryer 170.

[0112] In addition, when the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, it can be pumped by the roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the dissolving mixer 120.

[0113] The sludge cake storage area 140 is The dewatered sludge cake can be dropped, stored or transported to a storage area below the side of the dewaterer 130 by undergrounding the storage area below the side of the dewaterer.

[0114] In addition, the sludge cake storage area 140 is At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is input into the sludge cake storage area 140, The sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to prepare a slurry, which can be pumped and transported to the dissolving and mixing machine 120 by the roller vacuum type self-priming hose pump.

[0115] Here, in order to dissolve the chlorine bypass dust in water or an acidic aqueous solution, the dissolving agitator can be constructed underground so that its upper end is horizontal to the ground. This is because the storage area for sludge cake generated in the slurry dehydrator is constructed underground at the bottom of the side of the slurry dehydrator, and when the sludge cake is mixed with water or an acidic aqueous solution to turn it into sludge cake slurry and then transferred to the next dissolving agitator, the height difference between the bottom of the sludge cake storage area and the top of the dissolving agitator is minimized, thereby facilitating transportation and improving the operation rate.

[0116] In addition, the transfer line for transferring the slurry after stirring the chlorine bypass dust in water or an acidic aqueous solution with a dissolving agitator can be constructed by pumping the slurry from the upper part of the dissolving agitator, in order to prevent the clogging of the pipes that often occurs when the slurry is pumped from the lower part due to the high slurry concentration at the lower part of the agitator.

[0117] The environmentally friendly recycling system for cement chlorine bypass dust comprises: As a first dissolution, in the No. 1 dissolving mixer 120, the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; As a first dehydration step, the slurry is dehydrated by the slurry dehydrator 130 to produce a first sludge cake, which is then dropped into the sludge cake storage area, and the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a first regenerated slurry; a step of pumping the first regenerated slurry to the No. 2 dissolving and mixing machine 120 using a roller vacuum type self-priming hose pump; As a second dissolution, the first regenerated slurry transferred to the second dissolving mixer 120 is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; and In the second dehydration, the slurry is dehydrated by the slurry dehydrator 130 to produce a second sludge cake, which is then dropped into the sludge cake storage area 140, and the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a second regenerated slurry; The cement chlorine bypass dust can be recycled in an environmentally friendly manner by preventing the formation of scale in the piping, and the dissolving or dehydrating process can be carried out in one or more partial repeating steps and a continuous circulating step.

[0118] Here, the one or more continuous circulation steps or partial repeat steps may be performed 1 to 6 times.

[0119] In this case, the recycling efficiency of the cement chlorine bypass dust can be increased as the number of repetitions of the continuous circulation process or the partial repetition process increases.

[0120] In addition, in the one-time dissolution-dehydration-drying process, the cement chlorine bypass dust is charged into a dissolution mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of a potassium chloride precipitation tank, and a dryer condensate of a potassium chloride dryer to form a slurry.

[0121] Thereafter, the slurry dissolved in the dissolving stirrer can be dehydrated in a slurry dehydrator and separated into a sludge cake and a dehydrated filtrate.

[0122] In this case, when the slurry is transferred from the dissolving agitator to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the dissolving agitator.

[0123] The sludge cake is then transported to a sludge cake storage area to produce sludge for use as a calciner raw material.

[0124] The sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement auxiliary material having a reduced chlorine concentration, which can be used as a cement raw material.

[0125] The dehydrated filtrate can then be transferred to a potassium chloride precipitation tank to precipitate and settle potassium chloride, which can then be recovered.

[0126] In addition, the dehydrated filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0127] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0128] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0129] The dissolution-dehydration process is repeated twice: In the first dissolution, the cement chlorine bypass dust is put into the No. 1 dissolving mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of a potassium chloride precipitation tank, and a dryer condensate of a potassium chloride dryer to form a slurry.

[0130] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer is dehydrated in a slurry dehydrator, and the slurry can be separated into a first sludge cake and a first dehydration filtrate.

[0131] At this time, when the slurry is transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the No. 1 dissolving mixer.

[0132] Thereafter, the first sludge cake is dropped into the sludge cake storage area, and then the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a first regenerated slurry.

[0133] At this time, the first regenerated slurry can be pumped and transported to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0134] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0135] Then, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a second sludge cake and a second dehydrated filtrate.

[0136] Thereafter, the second sludge cake is dropped into the sludge cake storage area, and then sludge for use as a calciner raw material can be produced.

[0137] The second sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement auxiliary material with a reduced chlorine concentration, which can be used as a cement raw material.

[0138] At this time, the first dehydration filtrate and the second dehydration filtrate are transferred to a potassium chloride precipitation tank, where potassium chloride is precipitated and precipitated, and the potassium chloride can be recovered.

[0139] In addition, the first dehydration filtrate and the second dehydration filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0140] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0141] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0142] In addition, the dissolution-dehydration process is repeated three times. In the first dissolution, the cement chlorine bypass dust is charged into the No. 1 dissolving mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of the potassium chloride precipitation tank, and a condensed water of the potassium chloride dryer, to form a slurry.

[0143] Then, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a first sludge cake and a first dehydration filtrate.

[0144] At this time, when the slurry is transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the No. 1 dissolving mixer.

[0145] Thereafter, the first sludge cake is dropped into the sludge cake storage area, and then the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a first regenerated slurry.

[0146] At this time, the first regenerated slurry can be pumped and transported to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0147] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0148] Then, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a second sludge cake and a second dehydrated filtrate.

[0149] Thereafter, the second sludge cake is dropped into the sludge cake storage area, and then the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a second regenerated slurry.

[0150] At this time, the second regenerated slurry can be pumped and transported to the No. 3 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0151] Then, as a third dissolution, the second regenerated slurry transferred to the No. 3 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0152] Then, as the third dehydration, the slurry dissolved in the No. 3 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a third sludge cake and a third dehydrated filtrate.

[0153] Thereafter, the third sludge cake is dropped into the sludge cake storage area, and then sludge for use as a calciner raw material can be produced.

[0154] The third sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement additive with a reduced chlorine concentration, which can be used as a cement raw material.

[0155] At this time, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate are transferred to a potassium chloride precipitation tank, where potassium chloride is precipitated and precipitated, and the potassium chloride can be recovered.

[0156] In addition, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0157] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0158] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0159] And, the environmentally friendly recycling system of the cement chlorine bypass dust comprises: When the dissolving or dehydrating step is carried out in one or more partial repeat steps and a continuous circulation step, The more times the lysis or dehydration steps are repeated, the shorter the lysis time may be.

[0160] The potassium chloride precipitation tank 160 may be equipped with a constant or occasional heating device such as a hot wire or steam line on the bottom and sides.

[0161] A flocculant can be added to the potassium chloride settling tank 160. The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The organic polymeric compound may include starches, polyacrylamides, or derivatives thereof.

[0162] In addition, the environmentally friendly recycling system for the cement chlorine bypass dust is In order to shorten the time required for potassium chloride crystal precipitation in the potassium chloride precipitation tank 160, When the precipitation and settling of potassium chloride crystals occurs in the dehydrated filtrate transferred to the potassium chloride precipitation tank 160 and a supernatant liquid is generated in the precipitation tank, the supernatant liquid in the potassium chloride precipitation tank 160 is pumped and transferred using a roller vacuum type self-priming hose pump or a submersible pump, and can be used as mixed water for dissolution in the dissolving mixer 120.

[0163] Here, in the repeated process of dissolving the chlorine bypass dust in water or an acidic aqueous solution, separating the water or the aqueous solution from the sludge, and dehydrating, the downstream transfer line for the dehydrated filtrate generated in the slurry dehydrator is composed of two lines, a potassium chloride settling tank and a potassium chloride dryer, regardless of the number of dehydrations, and can be configured so that it can be transferred separately or simultaneously.

[0164] In addition, in the repeated process of dissolving chlorine bypass dust in water or acidic aqueous solution, separating water or aqueous solution from sludge, and dehydrating, the dehydrated filtrate generated in the slurry dehydrator can be transferred to the potassium chloride settling tank. This is to minimize the operation process of the potassium chloride dryer or to maximize economy by improving drying efficiency.

[0165] The potassium chloride precipitation tank may be provided with a constant or occasional heating device such as a hot wire or steam line at the bottom and sides to facilitate evaporation of water. This is to adjust the crystallization time of potassium chloride according to the change in the time required for the degree of supersaturation of potassium chloride caused by the evaporation of water from the dehydrated filtrate, depending on whether the heating device is operated or not.

[0166] In addition, in order to further shorten the potassium chloride crystallization time, the amount of the coagulant can be adjusted by adding it to the dehydrated filtrate transferred to the potassium chloride precipitation tank, in order to increase the settling speed of the potassium chloride particles that have crystallized out in the liquid and promote settling.

[0167] In order to further shorten the potassium chloride crystal precipitation time, when the precipitation and settling of potassium chloride crystals are taking place in the dehydrated filtrate transferred to the potassium chloride precipitation tank and a supernatant liquid is generated in the precipitation tank, the supernatant liquid is pumped and transferred and removed using a roller vacuum type self-priming hose pump, or is transferred to a dissolving agitator and used as mixed water for dissolution.

[0168] The environmentally friendly recycling system for cement chlorine bypass dust comprises: To completely eliminate wastewater generation, The condensed water of the sludge cake dryer 150 or the condensed water of the potassium chloride dryer 170 can be transported and used as the mixed water for dissolving in the dissolving mixer 120 and the mixed water for producing regenerated slurry for the sludge cake in the sludge cake storage site 140.

[0169] And, the environmentally friendly recycling system of the cement chlorine bypass dust comprises: The sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or aqueous solution and dehydrating it is transferred to an underground storage area under the side of the slurry dehydrator, and then transferred to a sludge cake dryer where the moisture content is reduced to 5% or less, enabling it to be produced into high-value-added dried sludge for use as a cement auxiliary material.

[0170] Here, the sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or an aqueous solution and dehydrating it is transported to an underground storage area below the side of the slurry dehydrator, and the subsequent transfer line is made up of two lines, a sludge cake dryer and a product sludge storage area, and can be configured to be transported separately or simultaneously.

[0171] [Environmentally friendly recycling method for cement chlorine bypass dust] The present invention provides an environmentally friendly recycling method for cement chlorine bypass dust, which is a by-product of the cement process, by preventing the formation of scale in piping and carrying out a dissolution or dehydration process in one or more partial repeat steps and a continuous circulation step.

[0172] The present invention provides an environmentally friendly method for recycling cement chlorine bypass dust, comprising the steps of: The cement chlorine bypass dust is introduced into one or more dissolving agitators 120, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry (S110); The slurry dissolved in the dissolving mixer 120 is transferred to the slurry dewatering machine 130 and separated into a sludge cake and a dewatered filtrate (S120); The dehydrated filtrate is transferred to one or more of the potassium chloride precipitation tanks 160, and potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals (S130); When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, In the environmentally friendly recycling method of the cement chlorine bypass dust, the dust is pumped by the roller vacuum type self-priming hose pump, thereby preventing the formation of scale in the piping, and the dissolving or dehydrating process can be carried out in one or more partial repeat processes or in a continuous circulation process.

[0173] The present invention provides an environmentally friendly recycling method for cement chlorine bypass dust, which is a by-product of the cement process, by preventing the formation of scale in the piping and performing the dissolution or dehydration process in one or more partial repeat processes or in a continuous circulation process, thereby providing a highly stable and economical process.

[0174] The environmentally friendly recycling method of the cement chlorine bypass dust comprises the steps of: The dehydrated filtrate separated in the slurry dehydrator 130 is transferred to one or more potassium chloride dryers 170 for drying and recovering potassium chloride (S140); or The method may further include a step of transferring the precipitate from the potassium chloride precipitation tank 160 to one or more potassium chloride dryers 170 for drying and recovering potassium chloride (S150).

[0175] And, the environmentally friendly recycling method of the cement chlorine bypass dust comprises: The sludge cake is transferred to a sludge cake storage site 140 and processed into sludge for use as a calciner raw material (S160); or The method may further include a step (S170) of transferring the sludge cake to a sludge cake dryer 150 to manufacture dried sludge for use as a cement auxiliary material.

[0176] The environmentally friendly recycling method of the cement chlorine bypass dust comprises the steps of: A step (S180) of feeding the supernatant of the potassium chloride precipitation tank 160 or the condensed water of the potassium chloride dryer 170 into the dissolving mixer 120 together with water or an acidic aqueous solution; or The dryer condensate of the potassium chloride dryer 170 or the dryer condensate of the sludge cake dryer 150 is input into a sludge cake storage site 140, and at least one selected from water, an acidic aqueous solution, the condensate of the sludge cake dryer 150, and the condensate of the potassium chloride dryer 170 is input into the sludge cake in the sludge cake storage site 140 to produce a regenerated slurry, and then the regenerated slurry is transferred to the dissolving mixer 120 (S190).

[0177] FIG. 2 is a process flow diagram of an environmentally friendly recycling method for cement chlorine bypass dust according to one embodiment of the present invention.

[0178] Referring to FIG. 2, one or more pieces of cement chlorine bypass dust are input into the dissolving mixer 120, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to form a slurry (S110).

[0179] Thereafter, the slurry dissolved in the dissolving mixer 120 is dehydrated in a slurry dehydrator 130 and separated into a sludge cake and a dehydrated filtrate (S120).

[0180] The dehydrated filtrate is then transferred to one or more of the potassium chloride settling tanks 160 to recover potassium chloride by precipitation and settling of potassium chloride crystals (S130).

[0181] Alternatively, the dehydrated filtrate is transferred to one or more of the potassium chloride dryers 170 for drying and recovery of potassium chloride (S140).

[0182] Alternatively, the precipitate precipitated in the potassium chloride precipitation tank 160 is transferred to one or more potassium chloride dryers 170 for drying, and potassium chloride is recovered (S150).

[0183] The sludge cake is then transferred to the sludge cake storage site 140 and processed into sludge for use as a calciner raw material (S160).

[0184] Thereafter, the sludge cake is transferred to a sludge cake dryer 150 to produce dried sludge for cement auxiliary material with reduced chlorine concentration, which can be used as a cement raw material (S170).

[0185] Then, the supernatant of the potassium chloride precipitation tank 160 or the condensed water of the potassium chloride dryer 170 is introduced into the dissolution mixer 120 together with water or an acidic aqueous solution (S180).

[0186] Finally, the dryer condensate of the potassium chloride dryer 170 or the dryer condensate of the sludge cake dryer 150 is input into the sludge cake storage site 140, and at least one selected from water, an acidic aqueous solution, the condensate of the sludge cake dryer 150, and the condensate of the potassium chloride dryer 170 is input into the sludge cake in the sludge cake storage site 140 to produce a regenerated slurry, and then the regenerated slurry is transferred to the dissolving mixer 120 (S190).

[0187] Here, the environmentally friendly recycling method for the cement chlorine bypass dust can prevent the formation of scale in the piping, and the dissolving or dehydrating process can be carried out by one or more partial repeating steps and a continuous circulation step.

[0188] Here, the one or more partial repeat steps may be 1 to 6 times.

[0189] In this case, as the number of times the partial repeat process is repeated increases, the recycling efficiency of the cement chlorine bypass dust can be increased.

[0190] The continuous circulation step may be a step in which the dissolving, dehydrating or drying step is continuously cycled one or more times.

[0191] At this time, when the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped from the upper part of the dissolving mixer 120.

[0192] In addition, the chlorine bypass dust contains not only a large amount of alkali and chlorine, but also calcium (Ca) and sulfate (SO4 2- ) ions, and when they come into contact with water or an acidic aqueous solution and are transported on a conveyor belt or pumped through a piping pump, they produce not only potassium chloride (KCl) but also calcium carbonate (CaCO3) and gypsum (CaSO4), which inevitably results in the formation of scale on the conveyor belt or piping.

[0193] Here, the roller vacuum type self-priming hose pump can discharge the slurry and regenerated slurry through the suction port and discharge port by using a high-pressure vacuum tube that expands and contracts and a compression rod that can be transported in forward and reverse directions.

[0194] Therefore, the roller vacuum type self-priming hose pump fundamentally prevents partial loading or clogging of solids during transportation caused by scale formed on a belt conveyor or piping, making it possible to repeat partial or entire processes and to continuously operate the entire process for a certain period of time or more.

[0195] In addition, the sludge cake dryer 150 may include a vertical cylindrical continuous dryer.

[0196] In the vertical cylindrical continuous dryer for drying sludge cake, the entire surface of the vertical cylinder is a drying cross section, and the sludge cake introduced into the vertical cylindrical continuous dryer adheres to the entire surface of the vertical cylindrical continuous dryer in the form of a thin film by centrifugal force and dries, so that the sludge can be dried in the form of a thin film.

[0197] Here, the vertical cylindrical continuous dryer for drying sludge cake has a thermal efficiency approximately one time higher than that of existing rotary dryers and spray dryers, and the evaporated steam is condensed and entirely recovered in the form of condensed water, which is subsequently used as mixed water. This means that no wastewater is generated, and the economic efficiency of the process is greatly improved.

[0198] In addition, the potassium chloride dryer 170 may include a vertical cylindrical continuous dryer.

[0199] In the vertical cylindrical continuous dryer for drying potassium chloride, the entire surface of the vertical cylinder is a drying cross section, and the sludge cake introduced into the vertical cylindrical continuous dryer adheres to the entire surface of the vertical cylindrical continuous dryer in the form of a thin film by centrifugal force and dries, so that the sludge can be dried in the form of a thin film.

[0200] Here, the vertical cylindrical continuous dryer for drying potassium chloride has a thermal efficiency approximately one time higher than that of existing rotary dryers and spray dryers, and the evaporating steam is condensed and entirely recovered in the form of condensed water, which is subsequently used as mixed water, so that no wastewater is generated and the economic efficiency of the process is greatly improved.

[0201] The one or more dissolving agitators 120 are placed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolution agitators 120; Dryer condensate of a potassium chloride dryer 170 may be further input to the one or more dissolving agitators 120, so that the cement chlorine bypass dust may be dissolved in the dryer condensate of the potassium chloride dryer 170.

[0202] In addition, when the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, it can be pumped by the roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the dissolving mixer 120.

[0203] The sludge cake storage area 140 is The dewatered sludge cake is dropped to the storage area at the bottom of the side of the dewaterer 130 and can be stored or transported there.

[0204] In addition, the sludge cake storage area 140 is At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is input into the sludge cake storage area 140, The sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to prepare a slurry, which can be pumped and transported to the dissolving and mixing machine 120 by the roller vacuum type self-priming hose pump.

[0205] Here, in order to dissolve the chlorine bypass dust in water or an acidic aqueous solution, the dissolving agitator can be constructed underground so that its upper end is horizontal to the ground. This is because the storage area for the sludge cake generated in the slurry dehydrator is constructed underground at the bottom side of the slurry dehydrator, and when the sludge cake is mixed with water or an acidic aqueous solution to turn it into a sludge cake slurry and then transferred to the next dissolving agitator, the height difference between the bottom of the sludge cake storage area and the top of the dissolving agitator is minimized, thereby facilitating transportation and improving the operation rate.

[0206] In addition, the transfer line for transferring the slurry after stirring the chlorine bypass dust in water or an acidic aqueous solution with a dissolving agitator can be constructed by pumping the slurry from the upper part of the dissolving agitator, in order to prevent the clogging of the pipes that often occurs when the slurry is pumped from the lower part due to the high slurry concentration at the lower part of the agitator.

[0207] And, the environmentally friendly recycling method of the cement chlorine bypass dust comprises: As a first dissolution, in the No. 1 dissolving mixer 120, the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; As a first dehydration step, the slurry is dehydrated by the slurry dehydrator 130 to produce a first sludge cake, which is then dropped into the sludge cake storage area, and the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a first regenerated slurry; a step of pumping and transferring the first regenerated slurry to the No. 2 dissolving and mixing machine 120 using a roller vacuum type self-priming hose pump; As a second dissolution, the first regenerated slurry transferred to the second dissolving mixer 120 is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; and In the second dehydration, the slurry is dehydrated by the slurry dehydrator 130 to produce a second sludge cake, which is then dropped into the sludge cake storage area 140, and the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a second regenerated slurry; The cement chlorine bypass dust can be recycled in an environmentally friendly manner by preventing the formation of scale in the piping, and the dissolving or dehydrating process can be carried out in one or more partial repeating steps and a continuous circulating step.

[0208] Here, the one or more continuous circulation steps or partial repeat steps may be performed 1 to 6 times.

[0209] In this case, the recycling efficiency of the cement chlorine bypass dust can be increased as the number of repetitions of the continuous circulation process or the partial repetition process increases.

[0210] In addition, in the one-time dissolution-dehydration-drying process, the cement chlorine bypass dust is charged into a dissolution mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of a potassium chloride precipitation tank, and a dryer condensate of a potassium chloride dryer to form a slurry.

[0211] Thereafter, the slurry dissolved in the dissolving stirrer can be dehydrated in a slurry dehydrator and separated into a sludge cake and a dehydrated filtrate.

[0212] In this case, when the slurry is transferred from the dissolving agitator to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the dissolving agitator.

[0213] The sludge cake is then transported to a sludge cake storage area to produce sludge for use as a calciner raw material.

[0214] The sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement auxiliary material having a reduced chlorine concentration, which can be used as a cement raw material.

[0215] The dehydrated filtrate can then be transferred to a potassium chloride precipitation tank to precipitate and settle potassium chloride, which can then be recovered.

[0216] In addition, the dehydrated filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0217] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0218] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0219] The dissolution-dehydration process is repeated twice: In the first dissolution, the cement chlorine bypass dust is put into the No. 1 dissolving mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of a potassium chloride precipitation tank, and a dryer condensate of a potassium chloride dryer to form a slurry.

[0220] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer is dehydrated in a slurry dehydrator, and the slurry can be separated into a first sludge cake and a first dehydration filtrate.

[0221] At this time, when the slurry is transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the No. 1 dissolving mixer.

[0222] Thereafter, the first sludge cake is dropped into the sludge cake storage area, and then the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a first regenerated slurry.

[0223] At this time, the first regenerated slurry can be pumped and transported to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0224] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0225] Then, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a second sludge cake and a second dehydrated filtrate.

[0226] Thereafter, the second sludge cake is dropped into the sludge cake storage area, and then sludge for use as a calciner raw material can be produced.

[0227] The second sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement auxiliary material with a reduced chlorine concentration, which can be used as a cement raw material.

[0228] At this time, the first dehydration filtrate and the second dehydration filtrate are transferred to a potassium chloride precipitation tank, where potassium chloride is precipitated and precipitated, and the potassium chloride can be recovered.

[0229] In addition, the first dehydration filtrate and the second dehydration filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0230] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0231] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0232] In addition, the dissolution-dehydration process is repeated three times. In the first dissolution, the cement chlorine bypass dust is charged into the No. 1 dissolving mixer, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant liquid of the potassium chloride precipitation tank, and a condensed water of the potassium chloride dryer, to form a slurry.

[0233] Then, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a first sludge cake and a first dehydration filtrate.

[0234] At this time, when the slurry is transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it can be pumped by a roller vacuum type self-priming hose pump, and the slurry can be pumped to a transfer line at the top of the No. 1 dissolving mixer.

[0235] Thereafter, the first sludge cake is dropped into the sludge cake storage area, and then the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a first regenerated slurry.

[0236] At this time, the first regenerated slurry can be pumped and transported to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0237] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0238] Then, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a second sludge cake and a second dehydrated filtrate.

[0239] Thereafter, the second sludge cake is dropped into the sludge cake storage area, and then the second sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer, and condensed water of the potassium chloride dryer to produce a second regenerated slurry.

[0240] At this time, the second regenerated slurry can be pumped and transported to the No. 3 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0241] Then, as a third dissolution, the second regenerated slurry transferred to the No. 3 dissolving mixer is dissolved in at least one selected from water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0242] Then, as the third dehydration, the slurry dissolved in the No. 3 dissolving mixer is dehydrated in a slurry dehydrator, and separated into a third sludge cake and a third dehydrated filtrate.

[0243] Thereafter, the third sludge cake is dropped into the sludge cake storage area, and then sludge for use as a calciner raw material can be produced.

[0244] The third sludge cake is then transferred to a sludge cake dryer to produce dried sludge for use as a cement additive with a reduced chlorine concentration, which can be used as a cement raw material.

[0245] At this time, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate are transferred to a potassium chloride precipitation tank, where potassium chloride is precipitated and precipitated, and the potassium chloride can be recovered.

[0246] In addition, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate can be transferred to a potassium chloride dryer to dry the potassium chloride and recover the potassium chloride.

[0247] The precipitate precipitated in the potassium chloride precipitation tank is transferred to a potassium chloride dryer and dried, so that potassium chloride can be recovered.

[0248] At this time, the transfer line is hardly clogged and almost no waste water is generated.

[0249] And, the environmentally friendly recycling method of the cement chlorine bypass dust comprises: When the dissolving or dehydrating step is carried out in one or more partial repeat steps and a continuous circulation step, The more times the lysis or dehydration steps are repeated, the shorter the lysis time may be.

[0250] The potassium chloride precipitation tank 160 may be equipped with a constant or occasional heating device such as a hot wire or steam line on the bottom and sides.

[0251] A flocculant can be added to the potassium chloride settling tank 160. The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The organic polymeric compounds may include starches or polyacrylamides and their derivatives.

[0252] The environmentally friendly recycling method of the cement chlorine bypass dust comprises the steps of: In order to shorten the time required for potassium chloride crystal precipitation in the potassium chloride precipitation tank 160, When the precipitation and settling of potassium chloride crystals occurs in the dehydrated filtrate transferred to the potassium chloride precipitation tank 160 and a supernatant liquid is generated in the precipitation tank, the supernatant liquid in the potassium chloride precipitation tank 160 is pumped and transferred using a roller vacuum type self-priming hose pump or a submersible pump, and can be used as mixed water for dissolution in the dissolving mixer 120.

[0253] Here, in the repeated process of dissolving the chlorine bypass dust in water or an acidic aqueous solution, separating the water or the aqueous solution from the sludge, and dehydrating, the downstream transfer line for the dehydrated filtrate generated in the slurry dehydrator is composed of two lines, a potassium chloride settling tank and a potassium chloride dryer, regardless of the number of dehydrations, and can be configured so that it can be transferred separately or simultaneously.

[0254] In addition, in the repeated process of dissolving chlorine bypass dust in water or an acidic aqueous solution, separating the water or aqueous solution from the sludge, and dehydrating, the dehydrated filtrate generated in the slurry dehydrator can be transferred to the potassium chloride settling tank. This is to minimize the operation process of the potassium chloride dryer or to maximize the economy by improving the drying efficiency.

[0255] The potassium chloride precipitation tank may be provided with a constant or occasional heating device such as a hot wire or steam line at the bottom and sides to facilitate evaporation of water. This is to adjust the crystallization time of potassium chloride according to the change in the time required for the degree of supersaturation of potassium chloride caused by the evaporation of water from the dehydrated filtrate, depending on whether the heating device is operated or not.

[0256] In addition, in order to further shorten the potassium chloride crystallization time, the amount of the coagulant can be adjusted by adding it to the dehydrated filtrate transferred to the potassium chloride precipitation tank, in order to increase the settling speed of the potassium chloride particles that have crystallized out in the liquid and promote settling.

[0257] In order to further shorten the potassium chloride crystal precipitation time, when the precipitation and sedimentation of potassium chloride crystals are taking place in the dehydrated filtrate transferred to the potassium chloride precipitation tank and a supernatant liquid is generated in the precipitation tank, the supernatant liquid is pumped and transferred and removed using a roller vacuum type self-priming hose pump, or is transferred to a dissolving agitator and used as mixed water for dissolution.

[0258] And, the environmentally friendly recycling method of the cement chlorine bypass dust comprises: To completely eliminate wastewater generation, The condensed water of the sludge cake dryer 150 or the condensed water of the potassium chloride dryer 170 can be transported and used as the mixed water for dissolving in the dissolving mixer 120 and the mixed water for producing regenerated slurry for the sludge cake in the sludge cake storage site 140.

[0259] The environmentally friendly recycling method of the cement chlorine bypass dust comprises the steps of: The sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or aqueous solution and dehydrating it is transferred to an underground storage area under the side of the slurry dehydrator, and then transferred to a sludge cake dryer where the moisture content is reduced to 5% or less, enabling it to be produced into high-value-added dried sludge for use as a cement auxiliary material.

[0260] Here, the sludge cake generated in the slurry dehydrator during the repeated process of separating the sludge from water or an aqueous solution and dehydrating it is transported to an underground storage area below the side of the slurry dehydrator, and the subsequent transfer line is made up of two lines, a sludge cake dryer and a product sludge storage area, and can be configured to be transported separately or simultaneously.

[0261] [Potassium chloride recovered from an environmentally friendly recycling system for cement chlorine bypass dust] The present invention provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling system.

[0262] The present invention is economical because it provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling system.

[0263] [Sludge with reduced chlorine concentration produced by an environmentally friendly recycling system for cement chlorine bypass dust] The present invention provides a sludge having a reduced chlorine concentration produced by the environmentally friendly recycling system of the cement chlorine bypass dust.

[0264] The present invention is economical because it provides a sludge with reduced chlorine concentration produced by the environmentally friendly recycling system of the cement chlorine bypass dust.

[0265] [Potassium chloride recovered through an environmentally friendly recycling method for cement chlorine bypass dust] The present invention provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling method.

[0266] The present invention provides potassium chloride recovered from the cement chlorine bypass dust in an environmentally friendly recycling method, which is economical.

[0267] [Sludge with reduced chlorine concentration produced by environmentally friendly recycling of cement chlorine bypass dust] The present invention provides a sludge having a reduced chlorine concentration produced by the environmentally friendly recycling method of the cement chlorine bypass dust.

[0268] The present invention is economical since it provides a sludge with reduced chlorine concentration produced by an environmentally friendly recycling method of said cement chlorine bypass dust.

[0269] The present invention will be described in more detail below with reference to examples. However, the following examples are provided to more specifically explain the present invention, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified or altered by those skilled in the art within the scope of the present invention.

[0270] <Example> Example 1: An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system with a 2-hour dissolution-dehydration-precipitation single-step process Cement chlorine bypass dust with a chlorine content of 189,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and a supernatant of a potassium chloride settling tank for 2 hours to form a slurry.

[0271] Thereafter, the slurry dissolved in the dissolving stirrer was dehydrated in a slurry dehydrator to separate it into a sludge cake and a dehydrated filtrate.

[0272] At this time, when the slurry was transferred from the dissolving stirrer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to a transfer line at the top of the dissolving stirrer.

[0273] The dehydrated filtrate was then transferred to a potassium chloride precipitation tank containing slaked lime (calcium hydroxide) as a flocculant, and potassium chloride was recovered by precipitation and sedimentation of potassium chloride crystals.

[0274] Here, the recovery rate of potassium chloride was 75.5% using the environmentally friendly recycling method of one-step dissolution-dehydration-precipitation for 2 hours.

[0275] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0276] <Example 2> An environmentally friendly recycling method using an environmentally friendly recycling system for cement chlorine bypass dust with a chlorine content of 189,000 ppm, with a single process of dissolution-dehydration-precipitation-drying for 2 hours Cement chlorine bypass dust with a chlorine content of 189,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 2 hours to form a slurry.

[0277] Thereafter, the slurry dissolved in the dissolving stirrer was dehydrated in a slurry dehydrator to separate it into a sludge cake and a dehydrated filtrate.

[0278] At this time, when the slurry was transferred from the dissolving stirrer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to a transfer line at the top of the dissolving stirrer.

[0279] Thereafter, the sludge cake was transported to a sludge cake storage area to produce sludge for use as a calciner raw material.

[0280] Thereafter, the sludge cake was transferred to a sludge cake dryer to produce dried sludge for cement auxiliary material with reduced chlorine concentration, which is used as a cement raw material.

[0281] The dehydrated filtrate was then transferred to a potassium chloride precipitation tank containing slaked lime (calcium hydroxide) as a flocculant, and potassium chloride was recovered by precipitation and sedimentation of potassium chloride crystals.

[0282] Thereafter, the sediment precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0283] Here, the recovery rate of potassium chloride recovered by the environmentally friendly recycling method of one-step dissolution-dehydration-precipitation-drying for two hours was 77.5%.

[0284] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0285] <Example 3> An environmentally friendly recycling method using an environmentally friendly recycling system for cement chlorine bypass dust with a chlorine content of 189,000 ppm, with a single process of dissolution-dehydration-precipitation-drying for 3 hours The same method as in Example 2 was carried out, except that the cement chlorine bypass dust having a chlorine content of 189,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 3 hours to form a slurry.

[0286] Here, the recovery rate of potassium chloride recovered by the environmentally friendly recycling method of one-step dissolution-dehydration-precipitation-drying for three hours was 81.5%.

[0287] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0288] Example 4: An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system with a 2-hour dissolution-dehydration-drying single process Cement chlorine bypass dust with a chlorine content of 189,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 2 hours to form a slurry.

[0289] Thereafter, the slurry dissolved in the dissolving stirrer was dehydrated in a slurry dehydrator to separate it into a sludge cake and a dehydrated filtrate.

[0290] At this time, when the slurry was transferred from the dissolving stirrer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to a transfer line at the top of the dissolving stirrer.

[0291] Thereafter, the sludge cake was transported to a sludge cake storage area to produce sludge for use as a calciner raw material.

[0292] Thereafter, the sludge cake was transferred to a sludge cake dryer to produce dried sludge for cement auxiliary material with reduced chlorine concentration, which is used as a cement raw material.

[0293] Thereafter, the dehydrated filtrate was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, to dry the potassium chloride and recover the potassium chloride.

[0294] Here, the recovery rate of potassium chloride was 75.5% using the environmentally friendly recycling method involving a single 2-hour dissolution-dehydration-drying process.

[0295] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0296] <Example 5> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system with two partial repetitions of dissolution-dehydration, precipitation-drying for 2 hours. In the first dissolution, cement chlorine bypass dust with a chlorine content of 189,000 ppm was charged into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and condensed water from a potassium chloride dryer for 2 hours to form a slurry.

[0297] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0298] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0299] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0300] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0301] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0302] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydration filtrate.

[0303] Thereafter, the second sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0304] The second sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0305] At this time, the first dehydration filtrate and the second dehydration filtrate were transferred to a potassium chloride precipitation tank containing polyacrylamide as a flocculant, and potassium chloride was recovered by precipitation and precipitation of potassium chloride crystals.

[0306] The precipitate precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0307] Here, the potassium chloride was recovered by an environmentally friendly recycling method using the partial repeat process of dissolution-dehydration twice, which consisted of two hours of dissolution-dehydration-precipitation-drying, and the recovery rate was 88.6%.

[0308] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0309] <Example 6> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system with two partial repetitions of dissolution-dehydration, precipitation-drying for 3 hours The same method as in Example 5 was carried out, except that the cement chlorine bypass dust having a chlorine content of 189,000 ppm was put into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 3 hours to form a slurry.

[0310] Here, the potassium chloride was recovered by an environmentally friendly recycling method using the partial repetition of dissolution-dehydration steps of the three-hour dissolution-dehydration-precipitation-drying process twice, and the recovery rate of the potassium chloride was 96.5%.

[0311] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0312] <Example 7> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system with two partial repetitions of dissolution-dehydration-drying for 2 hours In the first dissolution, cement chlorine bypass dust with a chlorine content of 189,000 ppm was charged into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and condensed water from a potassium chloride dryer for 2 hours to form a slurry.

[0313] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0314] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0315] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0316] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0317] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0318] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydrated filtrate.

[0319] Thereafter, the second sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0320] The second sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0321] At this time, the first dehydration filtrate and the second dehydration filtrate were transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, to dry the potassium chloride and recover the potassium chloride.

[0322] Here, the potassium chloride was recovered by an environmentally friendly recycling method using the partial repetition of the two-hour dissolution-dehydration-drying process twice, and the recovery rate was 85.6%.

[0323] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0324] <Example 8> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system, which involves a partial repetition process of dissolution-dehydration for 2 hours, followed by three times of dissolution-dehydration-precipitation-drying. In the first dissolution, cement chlorine bypass dust with a chlorine content of 189,000 ppm was put into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer for 2 hours to form a slurry.

[0325] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0326] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0327] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0328] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0329] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0330] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydration filtrate.

[0331] Then, the second sludge cake was dropped into the sludge cake storage area, and then the second sludge cake was mixed with water, an acidic aqueous solution, condensate from the sludge cake dryer, and condensate from the potassium chloride dryer to produce a second regenerated slurry.

[0332] At this time, the second regenerated slurry was pumped and transferred to the No. 3 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0333] Then, as the third dissolution, the second regenerated slurry transferred to the No. 3 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0334] Thereafter, as the third dehydration, the slurry dissolved in the No. 3 dissolving mixer was dehydrated in a slurry dehydrator and separated into a third sludge cake and a third dehydrated filtrate.

[0335] Thereafter, the third sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0336] The third sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0337] At this time, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate were transferred to a potassium chloride precipitation tank containing aluminum chloride as a flocculant, and potassium chloride was recovered by precipitation and precipitation of potassium chloride crystals.

[0338] The precipitate precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0339] Here, the potassium chloride was recovered using an environmentally friendly recycling method that involved three partial repetitions of the two-hour dissolution-dehydration-precipitation-drying process, and the recovery rate was 97.6%.

[0340] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0341] <Example 9> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system for three times of dissolution-dehydration partial repetition process of dissolution-dehydration-precipitation-drying for three hours. The same method as in Example 8 was carried out, except that the cement chlorine bypass dust having a chlorine content of 189,000 ppm was put into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank for 3 hours to form a slurry.

[0342] Here, the potassium chloride was recovered by an environmentally friendly recycling method involving three partial repetitions of the three-hour dissolution-dehydration process, and the recovery rate was 98.3%.

[0343] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0344] <Example 10> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 189,000 ppm using an environmentally friendly recycling system, which uses a partial repetition process of dissolution-dehydration-drying for 2 hours for three times. In the first dissolution, cement chlorine bypass dust with a chlorine content of 189,000 ppm was put into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer for 2 hours to form a slurry.

[0345] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0346] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0347] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0348] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0349] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0350] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydration filtrate.

[0351] Then, the second sludge cake was dropped into the sludge cake storage area, and then the second sludge cake was mixed with water, an acidic aqueous solution, condensate from the sludge cake dryer, and condensate from the potassium chloride dryer to produce a second regenerated slurry.

[0352] At this time, the second regenerated slurry was pumped and transferred to the No. 3 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0353] Then, as the third dissolution, the second regenerated slurry transferred to the No. 3 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0354] Thereafter, as the third dehydration, the slurry dissolved in the No. 3 dissolving mixer was dehydrated in a slurry dehydrator and separated into a third sludge cake and a third dehydrated filtrate.

[0355] Thereafter, the third sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0356] The third sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0357] At this time, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate were transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, to dry the potassium chloride and recover the potassium chloride.

[0358] Here, the potassium chloride was recovered using an environmentally friendly recycling method that involves a partial repetition of the dissolution-dehydration-drying process three times, and the recovery rate was 95.6%.

[0359] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0360] Example 11: An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system with a 2-hour dissolution-dehydration-precipitation single-step process Cement chlorine bypass dust having a chlorine content of 220,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and a supernatant of a potassium chloride settling tank 160 for 2 hours to form a slurry.

[0361] Thereafter, the slurry dissolved in the dissolving stirrer was dehydrated in a slurry dehydrator to separate it into a sludge cake and a dehydrated filtrate.

[0362] At this time, when the slurry was transferred from the dissolving stirrer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to a transfer line at the top of the dissolving stirrer.

[0363] The dehydrated filtrate was then transferred to a potassium chloride precipitation tank containing polyacrylamide as a flocculant, and potassium chloride was recovered by precipitation and sedimentation of potassium chloride crystals.

[0364] Here, the chlorine content of the calciner feed sludge produced by the environmentally friendly recycling method of the two-hour dissolution-dehydration-precipitation one-step process was 45,000 ppm.

[0365] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0366] Example 12: An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system with a 2-hour dissolution-dehydration-precipitation-drying single process Cement chlorine bypass dust with a chlorine content of 220,000 ppm was charged into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and condensed water of a potassium chloride dryer for 2 hours to form a slurry.

[0367] Thereafter, the slurry dissolved in the dissolving stirrer was dehydrated in a slurry dehydrator to separate it into a sludge cake and a dehydrated filtrate.

[0368] At this time, when the slurry was transferred from the dissolving stirrer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to a transfer line at the top of the dissolving stirrer.

[0369] Thereafter, the sludge cake was transported to a sludge cake storage area to produce sludge for use as a calciner raw material.

[0370] Thereafter, the sludge cake was transferred to a sludge cake dryer to produce dried sludge for cement auxiliary material with reduced chlorine concentration, which is used as a cement raw material.

[0371] The dehydrated filtrate was then transferred to a potassium chloride precipitation tank containing polyacrylamide as a flocculant, and potassium chloride was recovered by precipitation and sedimentation of potassium chloride crystals.

[0372] Thereafter, the sediment precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0373] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of one-step dissolution-dehydration-precipitation-drying for two hours was 43,000 ppm.

[0374] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0375] <Example 13> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system with a 3-hour dissolution-dehydration-precipitation-drying single process The same method as in Example 12 was carried out, except that the cement chlorine bypass dust having a chlorine content of 220,000 ppm was put into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 3 hours to form a slurry.

[0376] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of one-step dissolution-dehydration-precipitation-drying for three hours was 26,000 ppm.

[0377] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0378] Example 14: An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system, which involves two partial repetitions of dissolution-dehydration, precipitation-drying, and two hours of dissolution-dehydration. In the first dissolution, cement chlorine bypass dust with a chlorine content of 220,000 ppm was put into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer for 2 hours to form a slurry.

[0379] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0380] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0381] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0382] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0383] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0384] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydration filtrate.

[0385] Thereafter, the second sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0386] The second sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0387] At this time, the first dehydration filtrate and the second dehydration filtrate were transferred to a potassium chloride precipitation tank containing alum as a flocculant, and potassium chloride was recovered by precipitation and precipitation of potassium chloride crystals.

[0388] The precipitate precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0389] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of the partial repetition of dissolution-dehydration steps of two times, namely, dissolution-dehydration-precipitation-drying for two hours, was 21,000 ppm.

[0390] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0391] <Example 15> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system, which involves a partial repetition process of dissolution-dehydration, precipitation-drying for 3 hours, twice. The same method as in Example 14 was carried out, except that the cement chlorine bypass dust having a chlorine content of 220,000 ppm was put into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank for 3 hours to form a slurry.

[0392] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of the partial repetition of dissolution-dehydration steps twice, which consisted of three hours of dissolution-dehydration-precipitation-drying, was 4,200 ppm.

[0393] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0394] <Example 16> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system, which involves a partial repetition process of dissolution-dehydration, precipitation-drying for 2 hours, and three times of dissolution-dehydration. In the first dissolution, cement chlorine bypass dust with a chlorine content of 220,000 ppm was put into the No. 1 dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer for 2 hours to form a slurry.

[0395] Thereafter, as the first dehydration, the slurry dissolved in the No. 1 dissolving mixer was dehydrated in a slurry dehydrator to separate it into a first sludge cake and a first dehydration filtrate.

[0396] At this time, when the slurry was transferred from the No. 1 dissolving mixer to the slurry dewatering machine, it was pumped by a roller vacuum type self-priming hose pump, and the slurry was pumped to the transfer line at the top of the No. 1 dissolving mixer.

[0397] Thereafter, the first sludge cake was dropped into the sludge cake storage area, and then the first sludge cake was mixed with water, an acidic aqueous solution, condensed water from the sludge cake dryer, and condensed water from the potassium chloride dryer to produce a first regenerated slurry.

[0398] At this time, the first regenerated slurry was pumped and transferred to the No. 2 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0399] Then, as the second dissolution, the first regenerated slurry transferred to the No. 2 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0400] Thereafter, as the second dehydration, the slurry dissolved in the No. 2 dissolving mixer was dehydrated in a slurry dehydrator and separated into a second sludge cake and a second dehydration filtrate.

[0401] Then, the second sludge cake was dropped into the sludge cake storage area, and then the second sludge cake was mixed with water, an acidic aqueous solution, condensate from the sludge cake dryer, and condensate from the potassium chloride dryer to produce a second regenerated slurry.

[0402] At this time, the second regenerated slurry was pumped and transferred to the No. 3 dissolving and mixing machine using a roller vacuum type self-priming hose pump.

[0403] Then, as the third dissolution, the second regenerated slurry transferred to the No. 3 dissolving mixer was dissolved in water, an acidic aqueous solution, the supernatant of the potassium chloride precipitation tank, and the condensed water of the potassium chloride dryer to produce a slurry.

[0404] Thereafter, as the third dehydration, the slurry dissolved in the No. 3 dissolving mixer was dehydrated in a slurry dehydrator and separated into a third sludge cake and a third dehydrated filtrate.

[0405] Thereafter, the third sludge cake was dropped into the sludge cake storage area, and then sludge for use as a calciner raw material was produced.

[0406] The third sludge cake was then transferred to a sludge cake dryer to produce dried sludge for cement auxiliary use with a reduced chlorine concentration, which can be used as a cement raw material.

[0407] At this time, the first dehydration filtrate, the second dehydration filtrate, and the third dehydration filtrate were transferred to a potassium chloride precipitation tank containing slaked lime (calcium hydroxide) as a flocculant, and potassium chloride was recovered by precipitation and precipitation of potassium chloride crystals.

[0408] The precipitate precipitated in the potassium chloride precipitation tank was transferred to a potassium chloride dryer, which is a vertical cylindrical continuous dryer, and dried to recover potassium chloride.

[0409] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of the partial repetition of dissolution-dehydration steps of three times, namely, dissolution-dehydration-precipitation-drying for two hours, was 4,400 ppm.

[0410] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0411] <Example 17> An environmentally friendly recycling method for cement chlorine bypass dust with a chlorine content of 220,000 ppm using an environmentally friendly recycling system for three times of dissolution-dehydration partial repetition process of dissolution-dehydration-precipitation-drying for three hours. The same method as in Example 16 was carried out, except that the cement chlorine bypass dust having a chlorine content of 220,000 ppm was put into a dissolving mixer, and the cement chlorine bypass dust was dissolved in water, an acidic aqueous solution, a supernatant of a potassium chloride precipitation tank, and a condensate of a potassium chloride dryer for 3 hours to form a slurry.

[0412] Here, the chlorine content of the calciner raw material sludge produced by the environmentally friendly recycling method of the partial repetition of dissolution-dehydration three times, i.e., dissolution-dehydration-precipitation-drying for three hours, was 2,200 ppm.

[0413] In addition, transfer lines are rarely clogged and very little wastewater is generated.

[0414] Comparative Example 1: Recycling method for chlorine bypass dust The chlorine bypass dust was in the form of a solution, slurry, or sludge with a water content of about 60%, and was pumped through piping for separation, dehydration, and drying. It was then dried in a rotary dryer in the drying process.

[0415] At that time, clogging of the transfer lines occurred frequently, and wastewater was generated in the amount of several tens of tons per day.

[0416] Comparative Example 2: Recycling method of chlorine bypass dust The chlorine bypass dust was in the form of a solution, slurry, or sludge with a water content of about 60%. It was pumped through piping for separation, dehydration, and drying. It was then dried in a spray dryer in the drying process.

[0417] At that time, the transfer line was overloaded and wastewater was generated in the amount of several tens of tons per day.

[0418] So far, specific embodiments of the environmentally friendly recycling system and method for recycling cement chlorine bypass dust according to the present invention have been described. However, it is obvious that various modifications are possible without departing from the scope of the present invention.

[0419] Therefore, the scope of the present invention should not be limited to the above-described embodiment, but should be determined not only by the claims set forth below, but also by equivalents to these claims.

[0420] In other words, it should be understood that the above-described embodiments are illustrative in all respects and not limiting, and the scope of the present invention is indicated by the claims set forth below rather than by the detailed description, and all modifications and variations that come within the meaning and scope of the claims and their equivalents should be interpreted as being included within the scope of the present invention.

Claims

1. An environmentally friendly recycling system for cement chlorine bypass dust, comprising: one or more dissolving agitators 120 into which the cement chlorine bypass dust is introduced and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry; A slurry dewatering machine 130 for separating the slurry dissolved in the dissolving agitator into a sludge cake and a dewatered filtrate; and one or more potassium chloride settling tanks 160 into which the dewatered filtrate is transferred and potassium chloride is recovered by precipitation and sedimentation of potassium chloride crystals; When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, The one or more dissolving agitators 120 are installed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolving agitators 120; The one or more dissolving agitators 120 are further fed with dryer condensate of a potassium chloride dryer 170, and the cement chlorine bypass dust is dissolved in the dryer condensate of the potassium chloride dryer 170. An environmentally friendly recycling system for cement chlorine bypass dust.

2. The environmentally friendly recycling system for cement chlorine bypass dust comprises: a sludge cake storage area 140 to which the sludge cake is transferred; one or more sludge cake dryers 150 for drying sludge cake in the sludge cake storage area to form reduced-chlorine sludge for use as a cement feedstock; the one or more potassium chloride dryers 170, in which the dewatered filtrate is dried to recover potassium chloride; or The one or more potassium chloride dryers 170 are further included, in which the precipitate precipitated in the potassium chloride precipitation tank 160 is transported and dried, and potassium chloride is recovered. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 1.

3. The sludge cake storage area 140 includes: The slurry dewatering device 130 is disposed underground at the bottom of the side of the dewatering device, and the dewatered sludge cake is dropped to the storage area at the bottom of the side of the dewatering device, and is stored or transported thereto. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 2.

4. The sludge cake storage area 140 includes: At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is input into the sludge cake storage area 140, At least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 is mixed with the sludge cake to prepare a slurry, which is then pumped and transported to the dissolving and stirring machine 120 by the roller vacuum type self-priming hose pump. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 2.

5. The environmentally friendly recycling system for cement chlorine bypass dust comprises: As a first dissolution, in the No. 1 dissolving mixer 120, the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; As a first dehydration step, the slurry is dehydrated by the slurry dehydrator 130 to produce a first sludge cake, which is then dropped into the sludge cake storage area, and the first sludge cake is mixed with at least one selected from water, an acidic aqueous solution, condensed water from the sludge cake dryer 150, and condensed water from the potassium chloride dryer 170 to produce a first regenerated slurry; a step of pumping and transferring the first regenerated slurry to the second dissolving and mixing machine 120 using a roller vacuum type self-priming hose pump; As a second dissolution, the first regenerated slurry transferred to the second dissolving agitator 120 is dissolved in at least one selected from water, an acidic aqueous solution, a supernatant of the potassium chloride precipitation tank 160, and a condensed water of the potassium chloride dryer 170 to produce a slurry; and In the second dehydration, the slurry is dehydrated by the slurry dehydrator 130 to produce a second sludge cake, and the second sludge cake falls into the sludge cake storage area 140. The second sludge cake is then mixed with at least one selected from water, an acidic aqueous solution, condensed water of the sludge cake dryer 150, and condensed water of the potassium chloride dryer 170 to produce a second regenerated slurry. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 2.

6. The environmentally friendly recycling system for cement chlorine bypass dust comprises: When the dissolving or dehydrating step is carried out in one or more partial repeat steps and a continuous circulation step, The more the number of repeated dissolution or dehydration steps increases, the shorter the dissolution time becomes. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 1.

7. The potassium chloride precipitation tank 160 is characterized in that it is equipped with a constant or occasional heating device such as a hot wire or steam line on the bottom and side. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 1.

8. A flocculant may be added to the potassium chloride precipitation tank 160. The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The present invention is characterized in that the organic polymer compound contains starch or polyacrylamide and its derivatives. The environmentally friendly recycling system for cement chlorine bypass dust according to claim 1.

9. 1. An environmentally friendly method for recycling cement chlorine bypass dust, comprising: The cement chlorine bypass dust is introduced into one or more dissolving agitators 120, and the cement chlorine bypass dust is dissolved in at least one selected from water, an acidic aqueous solution, and a supernatant of a potassium chloride precipitation tank 160 to form a slurry (S110); The slurry dissolved in the dissolving agitator 120 is transferred to a slurry dewatering device 130 and separated into a sludge cake and a dewatered filtrate (S120); and The dehydrated filtrate is transferred to one or more of the potassium chloride precipitation tanks 160 to recover potassium chloride by precipitation and sedimentation of potassium chloride crystals (S130); When the slurry is transferred from the dissolving mixer 120 to the slurry dewatering machine 130, the slurry is pumped by a roller vacuum type self-priming hose pump, The environmentally friendly recycling method for cement chlorine bypass dust is characterized in that the cement chlorine bypass dust is pumped by the roller vacuum type self-priming hose pump to prevent scale formation in the piping, and the dissolving or dehydrating process is carried out in one or more partial repeating steps or in a continuous circulating step; The one or more dissolving agitators 120 are installed underground so that the upper end of the dissolving agitator 120 is horizontal to the ground. The slurry is pumped above the one or more dissolving agitators 120; The one or more dissolving agitators 120 are further fed with dryer condensate of a potassium chloride dryer 170, and the cement chlorine bypass dust is dissolved in the dryer condensate of the potassium chloride dryer 170. An environmentally friendly recycling method for cement chlorine bypass dust.

10. The environmentally friendly recycling method of the cement chlorine bypass dust comprises: The dehydrated filtrate separated in the slurry dehydrator 130 is transferred to one or more potassium chloride dryers 170 for drying and recovering potassium chloride (S140); or The method further includes a step (S150) of transferring the precipitate precipitated in the potassium chloride precipitation tank 160 to one or more potassium chloride dryers 170 to dry the precipitate and recover potassium chloride. The environmentally friendly recycling method of cement chlorine bypass dust according to claim 9.

11. The environmentally friendly recycling method of the cement chlorine bypass dust comprises: The sludge cake is transferred to a sludge cake storage site 140 and processed into sludge for use as a calciner raw material (S160); or The sludge cake is transferred to a sludge cake dryer 150 to produce dried sludge for cement auxiliary material (S170). The environmentally friendly recycling method of cement chlorine bypass dust according to claim 9.

12. The environmentally friendly recycling method of the cement chlorine bypass dust comprises: A step of feeding the supernatant of the potassium chloride precipitation tank 160 or the condensed water of the potassium chloride dryer 170 into the dissolving mixer 120 together with water or an acidic aqueous solution (S180); or The dryer condensate of the potassium chloride dryer 170 or the dryer condensate of the sludge cake dryer 150 is input to a sludge cake storage 140, and at least one selected from water, an acidic aqueous solution, the condensate of the sludge cake dryer 150, and the condensate of the potassium chloride dryer 170 is input to the sludge cake in the sludge cake storage 140 to prepare a regenerated slurry, and then the regenerated slurry is transferred to the dissolving agitator 120 (S190); The environmentally friendly recycling method of cement chlorine bypass dust according to claim 9.

13. A flocculant may be added to the potassium chloride precipitation tank 160. The flocculant is at least one selected from the group consisting of slaked lime (calcium hydroxide), alum, aluminum chloride, iron (III) oxide, and iron (II) sulfate as an inorganic electrolyte, or The organic polymer compound contains starch, polyacrylamide, or a derivative thereof. The environmentally friendly recycling method of cement chlorine bypass dust according to claim 9.

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