Ammonium chloride drying fluidized bed furnace washing wastewater treatment system

Abstract

The utility model provides an ammonium chloride drying fluidized bed furnace washing wastewater treatment system, and belongs to the technical field of wastewater treatment. A furnace washing wastewater treatment system for an ammonium chloride drying fluidized bed comprises a wastewater collecting tank, a first regulating tank connected with an outlet of the wastewater collecting tank, a coagulating tank connected with an outlet of the first regulating tank, a second regulating tank connected with an outlet of the coagulating tank, and a preheater connected with an outlet of the second regulating tank, the desorption tower is connected with the preheater through a first pipeline, the tower top of the desorption tower is connected with a condenser, the condenser is connected to an ammonia absorption tower of the combined-soda system, the tower bottom of the desorption tower is connected with a cooler, and the cooler is connected to a salt dissolving workshop through a second pipeline. The device is used for effectively treating wastewater and realizing comprehensive recycling of ammonia nitrogen and chloride ions.

Description

Technical Field

[0001] The utility model belongs to the technical field of wastewater treatment, and in particular relates to an ammonium chloride drying fluidized bed furnace washing wastewater treatment system. Background Art

[0002] The combined alkali process is a mature process for producing soda ash and ammonium chloride at the same time. This process uses salt as raw material and produces soda ash and ammonium chloride through the combined action of ammonia and carbon dioxide. This process generally uses a fluidized bed to dry ammonium chloride, but after a period of operation, scarring and collapse will occur in the fluidized bed, causing the fluidized bed to be unable to operate and need to be stopped for treatment. The most effective treatment measure is water washing, but water washing will cause wastewater to be generated. If the wastewater is not used, it will not only pollute the environment, but also occupy the liquid level of the bucket, and cause a waste of resources and increase production costs.

[0003] For a long time, domestic alkali-related enterprises have been studying and treating ammonium chloride production wastewater to achieve standard discharge, but there are few reports on the recycling of ammonia nitrogen and chloride ions. In view of this, an ammonium chloride drying fluidized bed furnace washing wastewater treatment system is proposed to solve the problem of effective utilization of the corresponding wastewater. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide an ammonium chloride drying fluidized bed furnace washing wastewater treatment system in view of the deficiencies of the prior art, so as to effectively treat the wastewater and realize the comprehensive recovery and utilization of ammonia nitrogen and chloride ions.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: an ammonium chloride drying fluidized bed furnace washing wastewater treatment system, comprising a wastewater collection tank, a first regulating tank connected to the outlet of the wastewater collection tank, a coagulation tank connected to the outlet of the first regulating tank, a second regulating tank connected to the outlet of the coagulation tank, a preheater connected to the outlet of the second regulating tank, an analysis tower connected to the preheater through a first pipeline, a condenser connected to the top of the analysis tower, the condenser is connected to the ammonia absorption tower of the alkali system, the bottom of the analysis tower is connected to a cooler, and the cooler is connected to the salt workshop through a second pipeline.

[0006] Optionally, a plurality of grids are provided in the wastewater collection tank.

[0007] Optionally, the first regulating tank is a sedimentation regulating tank.

[0008] Optionally, the coagulation tank is respectively connected to a coagulant dosing device and a flocculant dosing device, polyferric sulfate is arranged in the coagulant dosing device, and polyacrylamide is arranged in the flocculant dosing device.

[0009] Optionally, the second regulating tank is connected to an alkali agent dosing device, and sodium hydroxide is arranged in the alkali agent dosing device.

[0010] Optionally, the outlet water of the second regulating tank is connected to a preheater via a pump, and the desorption tower is connected to a steam pipeline for desorption.

[0011] Optionally, the sodium chloride clear liquid flowing out from the bottom of the analytical tower is connected to a cooler through a pump for cooling.

[0012] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0013] The utility model is based on the above-mentioned treatment system. The ammonium chloride production wastewater is collected in the wastewater collection tank, and the debris such as stones, hemp tendons and hair are intercepted by the grille. Since the wastewater comes from various production sections, the water quality and quantity are discharged irregularly. In order to make the subsequent treatment facilities operate normally, a sedimentation regulating tank is set after the wastewater collection tank to balance the water quantity, uniform the water quality, and precipitate suspended matter such as sand and clay. Then, after the wastewater enters the coagulation tank, polyferric sulfate (coagulant) is added, stirred quickly, and then polyacrylamide PAM (flocculant) is added and stirred slowly. Then, the supernatant enters the pH adjustment tank, sodium hydroxide is added to alkaline, and ammonium ions are converted into free ammonia. The ammonia-containing wastewater coming out of the pH adjustment tank is pumped through the preheater to the desorption tower, and steam is introduced for analysis. The ammonia gas coming out of the top of the tower is cooled in the condenser and returned to the ammonia absorption tower of the alkali system for mother liquor absorption. The sodium chloride clear night flowing out of the bottom of the tower is cooled by the pump cooler, and then goes to the salt workshop for salt.

[0014] The treatment system of the utility model has the following advantages: (1) it realizes the organic combination of pollutant treatment and useful material recovery, thereby achieving the recycling of raw materials and zero wastewater discharge; (2) the stripping method is used to treat ammonia nitrogen, which not only ensures the recovery and utilization of ammonia, but also provides high-quality brine for the salt workshop of the original production system, which is conducive to reducing production costs; (3) compared with other treatment and recovery processes, it has good sedimentation and separation effects, and high removal and recovery rates; (4) the equipment occupies a small area, the volume of residual sludge is small, and the project investment and operating costs are low. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 : A schematic diagram of the structure of an ammonium chloride drying fluidized bed furnace washing wastewater treatment system of the utility model;

[0017] Among them, 1. Wastewater collection tank; 2. First regulating tank; 3. Coagulation tank; 4. Second regulating tank; 5. Preheater; 6. Analysis tower; 7. Condenser; 8. Ammonia absorption tower; 9. Cooler; 10. Salt workshop; 11. Coagulant dosing device; 12. Flocculant dosing device; 13. Alkali dosing device; 14. First pipeline; 15. Second pipeline. DETAILED DESCRIPTION

[0018] In order to better understand the present invention, the content of the present invention is further clearly described below in conjunction with the embodiments, but the protection content of the present invention is not limited to the following embodiments. In the following description, a large number of specific details are given in order to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details.

[0019] The use of words such as "first" and "second" to limit components is only to facilitate the distinction between corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0020] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this patent, and cannot be understood as limiting the present invention.

[0021] like Figure 1 As shown, an ammonium chloride drying fluidized bed furnace washing wastewater treatment system includes a wastewater collecting tank 1, a first regulating tank 2 connected to the outlet of the wastewater collecting tank 1, a coagulation tank 3 connected to the outlet of the first regulating tank 2, a second regulating tank 4 connected to the outlet of the coagulation tank 3, a preheater 5 connected to the outlet of the second regulating tank 4, a decomposition tower 6 connected to the preheater 5 through a first pipeline 14, a condenser 7 connected to the top of the decomposition tower 6, the condenser 7 is connected to the ammonia absorption tower 8 of the alkali system, the bottom of the decomposition tower 6 is connected to the cooler 9, and the cooler 9 is connected to the salt workshop 10 through a second pipeline 15.

[0022] The combined alkali process is used to produce sodium carbonate and ammonium chloride, and the mother liquor is recycled to improve the utilization rate of sodium chloride. In the treatment process of ammonium chloride production wastewater, not only pollutants such as COD and S should be removed, but also ammonia nitrogen and chloride ions should be recovered to the maximum extent to reduce costs and improve benefits.

[0023] The utility model adopts the steam stripping method to treat ammonia nitrogen. The pH of ammonium chloride production wastewater is less than 7, close to neutral, and the ammonia nitrogen is mainly in the form of ammonium ions (NH4+ ) exists in the form of alkali, so alkali must be added before steaming to adjust the wastewater pH to above 11, so that ammonium ions are converted into free ammonia, and the evaporated ammonia gas goes to the ammonia absorption tower 8 of the alkali system for absorption by the mother liquor. This system adjusts the pH by adding sodium hydroxide, which not only avoids the risk of equipment blockage caused by adding lime to generate precipitation, but also introduces a large amount of sodium ions at the same time, laying the foundation for the next step of recovering sodium chloride.

[0024] According to the water quality characteristics and engineering experience, the utility model adopts the coagulation precipitation method. Polyferric sulfate has a larger relative molecular weight than other inorganic salt coagulants, and has a better coagulation effect during use, especially for COD removal. In addition, it is suitable for raw wastewater with a pH in the alkaline range, which is close to the water liquid after the stripping method removes ammonia nitrogen, so polyferric sulfate is selected as the coagulant. Once the pollutants are removed, the raw wastewater becomes a dilute sodium chloride solution and is directly sent to the brine workshop for salting.

[0025] In some embodiments, a plurality of grids are provided in the wastewater collection tank 1 to intercept debris such as stones, hemp tendons and hair.

[0026] In some embodiments, the first regulating tank 2 is a sedimentation regulating tank to balance the water volume, make the water quality uniform, and simultaneously precipitate suspended matter such as sand and clay.

[0027] In some implementation schemes, the coagulation tank 3 is connected to the coagulant dosing device 11 and the flocculant dosing device 12 respectively, the coagulant dosing device 11 is provided with polyferric sulfate, and the flocculant dosing device 12 is provided with polyacrylamide.

[0028] In some embodiments, the second regulating tank 4 is connected to the alkali agent dosing device 13, and sodium hydroxide is arranged in the alkali agent dosing device 13. Alkali is added to adjust the pH of the wastewater to above 11 to convert ammonium ions into free ammonia.

[0029] In some embodiments, the effluent from the second regulating tank 4 is connected to the preheater 5 via a pump, and the desorption tower 6 is connected to the steam pipeline for desorption.

[0030] In some embodiments, the sodium chloride clear liquid flowing out of the bottom of the analytical tower 6 is connected to the cooler 9 through a pump for cooling.

[0031] Wastewater from ammonium chloride production is collected in the wastewater collection tank 1, and debris such as stones, hemp tendons and hair are intercepted by the grille. Since the wastewater comes from various production sections, the water quality and quantity are discharged irregularly. In order to ensure the normal operation of the subsequent treatment facilities, a sedimentation and adjustment tank is set after the wastewater collection tank 1 to balance the water volume, uniform the water quality, and precipitate suspended matter such as sand and clay. Then, after the wastewater enters the coagulation tank 3, polyferric sulfate (coagulant) is added, stirred quickly, and then polyacrylamide PAM (flocculant) is added and stirred slowly. Then, the supernatant enters the pH adjustment tank, sodium hydroxide is added until it is alkaline, and ammonium ions are converted into free ammonia. The ammonia-containing wastewater from the pH adjustment tank is pumped through the preheater 5 to the desorption tower, and steam is introduced for analysis. The ammonia gas coming out of the top of the tower enters the condenser 7 for cooling, and then returns to the ammonia absorption tower 8 of the joint alkali system for absorption by the mother liquor; the sodium chloride clear night flowing out of the bottom of the tower is cooled by the pump cooler 9, and then goes to the salt workshop 10 for salt.

[0032] The Lian Alkali Plant uses this system to treat ammonium chloride production wastewater, and has achieved very good results. It not only solves the pollution problems of ammonia nitrogen, COD, S and chloride ions, but also turns waste into treasure, achieving the goal of comprehensive resource utilization.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the utility model by ordinary technicians in this field should be included in the scope of the claims of the utility model as long as they do not depart from the spirit and scope of the technical solution of the utility model.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system, characterized in that: It includes a wastewater collection tank, a first regulating tank connected to the outlet of the wastewater collection tank, a coagulation tank connected to the outlet of the first regulating tank, a second regulating tank connected to the outlet of the coagulation tank, a preheater connected to the outlet of the second regulating tank, an analysis tower connected to the preheater through a first pipeline, a condenser connected to the top of the analysis tower, the condenser is connected to the ammonia absorption tower of the alkali system, a cooler is connected to the bottom of the analysis tower, and the cooler is connected to the salt workshop through a second pipeline.

2. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 1, characterized in that: A plurality of grids are arranged in the wastewater collection tank.

3. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 2, characterized in that: The first regulating tank is a sedimentation regulating tank.

4. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 3, characterized in that: The coagulation tank is connected to a coagulant dosing device and a flocculant dosing device respectively. Polyferric sulfate is arranged in the coagulant dosing device, and polyacrylamide is arranged in the flocculant dosing device.

5. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 4, characterized in that: The second regulating tank is connected to an alkali agent dosing device, and sodium hydroxide is arranged in the alkali agent dosing device.

6. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 5, characterized in that: The outlet water of the second regulating tank is connected to the preheater through a pump, and the desorption tower is connected to the steam pipeline for desorption.

7. An ammonium chloride drying fluidized bed furnace washing wastewater treatment system as claimed in claim 6, characterized in that: The sodium chloride clear liquid flowing out of the bottom of the analytical tower is connected to a cooler through a pump for cooling.

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