A system and method for co-disposal of phosphorus-containing industrial waste salt with fly ash water wash

Abstract

The present application relates to waste incineration fly ash treatment technical field, especially to a kind of system and method for containing phosphorus industrial waste salt and fly ash water washing liquid co-disposal.The technical scheme provided by the present application is by using waste incineration fly ash water washing liquid and the first industrial waste salt containing inorganic phosphorus mixed reaction occurs precipitation, then the mixed solution is filtered, to filter out organic matter and insoluble substance in mixed solution, then the filtered mixed solution is heated, to make the filtered mixed solution evaporate and concentrate, finally using electrolytic device to the mixed solution of evaporation and concentration electrolysis, to obtain chlorine, hydrogen, brine and rich sodium lye.Therefore this kind of based on waste incineration fly ash water washing liquid treatment technology and industrial waste salt technology processing mode, not only can realize the resource utilization of waste incineration fly ash water washing liquid, reduce impurity removal cost, but also can be absorbed industrial waste salt, realize the economic and environmental benefits of collaborative disposal.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fly ash water washing liquid processing, and particularly relates to a system and method for co-disposing industrial waste salt containing phosphorus and fly ash water washing liquid. BACKGROUND

[0002] A large amount of incineration fly ash is generated in the process of incineration treatment of garbage, and is listed as hazardous waste due to containing harmful substances such as excessive heavy metals. At present, the incineration fly ash of garbage is mostly disposed of in a cement kiln after water washing. The fly ash water washing liquid obtained in this way is usually used for electrolysis to realize resource utilization of the fly ash water washing liquid. However, this method will generate a high impurity removal cost in the process of solution refining.

[0003] Therefore, there is an urgent need for a system and method for co-disposing industrial waste salt containing phosphorus and fly ash water washing liquid to solve the technical problem. SUMMARY

[0004] The present application provides a system and method for co-disposing industrial waste salt containing phosphorus and fly ash water washing liquid, which can not only effectively realize resource utilization of the fly ash water washing liquid of garbage incineration, but also reduce the impurity removal cost and eliminate the economic and environmental benefits of industrial waste salt in waste system disposal.

[0005] In a first aspect, the present application provides a system for co-disposing industrial waste salt containing phosphorus and fly ash water washing liquid, comprising a mixing device, a filtering assembly, a heating device and an electrolysis device connected in sequence. The mixing device is used to accommodate a mixed solution of garbage incineration fly ash water washing liquid and a first industrial waste salt containing inorganic phosphorus. The filtering assembly is used to filter insoluble substances and organic matters in the mixed solution. The insoluble substances include solid suspensions and calcium phosphate precipitates obtained by the reaction of calcium ions in the water washing liquid and phosphate ions in the mixed solution. The heating device is used to heat the mixed solution output by the filtering assembly to evaporate and concentrate the mixed solution. The electrolysis device is used to electrolyze the mixed solution after evaporation and concentration to obtain chlorine, hydrogen, brine and sodium-rich lye.

[0006] In a second aspect, the present application provides a method for co-disposing industrial waste salt containing phosphorus and fly ash water washing liquid, applied to the system described in the above embodiment, comprising:

[0007] Accommodating, by the mixing device, a mixed solution of garbage incineration fly ash water washing liquid and a first industrial waste salt containing inorganic phosphorus;

[0008] Filtering, by the filtering assembly, insoluble substances and organic matters in the mixed solution;

[0009] Heating, by the heating device, the mixed solution output by the filtering assembly to evaporate and concentrate the mixed solution;

[0010] The mixed solution after evaporation and concentration is electrolyzed by the electrolysis device to obtain chlorine, hydrogen, dilute brine and sodium-rich lye.

[0011] It can be seen from the above solutions that the system and method for co-disposing phosphorus-containing industrial waste salt and fly ash water washing liquid provided by the application can realize resource utilization of the fly ash water washing liquid, reduce the cost of impurity removal, and realize the economic and environmental benefits of collaborative disposal. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor based on these drawings.

[0013] Figure 1 The system schematic diagram of the system for co-disposing phosphorus-containing industrial waste salt and fly ash water washing liquid provided by the embodiment of the application.

[0014] Figure 2 The method schematic diagram of the method for co-disposing phosphorus-containing industrial waste salt and fly ash water washing liquid provided by the embodiment of the application. Figure 1 The method schematic diagram of the method for co-disposing phosphorus-containing industrial waste salt and fly ash water washing liquid provided by the embodiment of the application.

[0015] Reference signs:

[0016] 1-mixing device;

[0017] 2-filtration assembly;

[0018] 3-heating device;

[0019] 4-electrolysis device;

[0020] 5-condensing device;

[0021] 6-cooling device. DETAILED DESCRIPTION

[0022] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0023] Referring to Figure 1 In an embodiment of the present application, a system for co-processing phosphorus-containing industrial waste salt and fly ash water washing liquid is provided. The system comprises, in sequence, a mixing device 1, a filtering assembly 2, a heating device 3 and an electrolysis device 4. The mixing device 1 is used to accommodate a mixed solution of garbage incineration fly ash water washing liquid and a first industrial waste salt containing inorganic phosphorus. The filtering assembly 2 is used to filter insoluble substances, organic matter and calcium ions in the mixed solution. The insoluble substances include solid suspensions and calcium phosphate precipitates obtained by the reaction of calcium ions in the water washing liquid and phosphate ions in the mixed solution. The heating device 3 is used to heat the mixed solution output by the filtering assembly 2 to evaporate and concentrate the mixed solution. The electrolysis device 4 is used to electrolyze the evaporated and concentrated mixed solution to obtain chlorine, hydrogen, brine and sodium-rich lye.

[0024] In the embodiment, by using garbage incineration fly ash water washing liquid and a first industrial waste salt containing inorganic phosphorus to mix and react to precipitate, then filtering the mixed solution to filter out organic matter and insoluble substances in the mixed solution, then heating the filtered mixed solution to evaporate and concentrate the filtered mixed solution, and finally using the electrolysis device 4 to electrolyze the evaporated and concentrated mixed solution to obtain chlorine, hydrogen, brine and sodium-rich lye. Therefore, this processing method based on garbage incineration fly ash water washing liquid processing technology and industrial waste salt technology not only realizes the resource utilization of garbage incineration fly ash water washing liquid and reduces the cost of impurity removal, but also absorbs industrial waste salt and realizes the economic and environmental benefits of collaborative disposal.

[0025] In the embodiment, the inorganic phosphorus can be sodium phosphate, sodium hydrogen phosphate, potassium phosphate and potassium hydrogen phosphate, and the specific composition of the inorganic phosphorus is not limited herein. The hydrogen phosphate ions in sodium hydrogen phosphate and potassium hydrogen phosphate in the mixed solution will further generate phosphate ions to realize the reaction with calcium ions and generate calcium phosphate precipitates.

[0026] In the production process of medicine and chemical industry, a large amount of inorganic waste salt water will be produced due to the use of a large amount of acid or alkaline substances, and finally form chemical waste salt. For example, phosphorus-containing medical waste salt, sodium sulfate type medical waste salt and the like, because they contain a large amount of inorganic salts such as sodium phosphate and organic pollutants such as dimethyl aniline, they cannot be directly landfilled, and the cost of other disposal methods is relatively high, so many enterprises are faced with the phenomenon of waste salt accumulation and cannot be consumed. Therefore, the inventors creatively consider mixing the waste incineration fly ash washing liquid with the first industrial waste salt to achieve the purpose of waste treatment with waste.

[0027] In addition, the second industrial waste salt containing glyphosate can also be mixed in the mixing device 1, so that the waste incineration fly ash washing liquid and the second industrial waste containing glyphosate can be mixed to generate precipitation through the reaction, that is, the calcium ions will react with the organic glyphosate to generate precipitation, and further remove the calcium ions and the organic glyphosate.

[0028] The production process of glyphosate by glycine method will produce a large amount of hazardous waste mother liquor, and the production enterprises mainly adopt two combined processes of membrane treatment / high temperature catalytic oxidation and multi-effect evaporation / directional conversion to treat the mother liquor. However, a large amount of disodium hydrogen phosphate, sodium pyrophosphate, sodium chloride and other waste salts will be produced in the treatment process, which contain organic pollutants such as glyphosate and aminomethyl phosphonic acid. These waste salts are generally accumulated in the warehouse of the enterprise waiting for policy arrangement for treatment. In the production process of medicine and chemical industry, a large amount of inorganic waste salt water will be produced due to the use of a large amount of acid or alkaline substances, and finally form chemical waste salt. For example, phosphorus-containing medical waste salt, sodium sulfate type medical waste salt and the like, because they contain a large amount of inorganic salts such as sodium phosphate and organic pollutants such as dimethyl aniline, they cannot be directly landfilled, and the cost of other disposal methods is relatively high, so many enterprises are faced with the phenomenon of waste salt accumulation and cannot be consumed. Therefore, the inventors creatively consider mixing the waste incineration fly ash washing liquid with the first industrial waste salt and the second industrial waste salt to achieve the purpose of waste treatment with waste.

[0029] In the present embodiment, the first industrial waste salt containing inorganic phosphorus can be a solid waste salt or a liquid waste salt solution, which is not limited herein, and the second industrial waste salt containing glyphosate can be a solid waste salt or a liquid waste salt solution, which is not limited herein. When the first industrial waste salt and the second industrial waste salt are solid waste salts, the waste incineration fly ash washing liquid is used to dissolve the first and second industrial waste salts to obtain a mixed solution. Specifically, a container for containing the waste incineration fly ash washing liquid can be placed on the ground, the waste incineration fly ash washing liquid enters from the bottom of the container and flows out from the top, and the first and second industrial salts are added to the middle position of the upper part of the container. In this way, the waste incineration fly ash washing liquid can not damage the impurity particles during self-flowing, which is beneficial to the settlement of the impurity particles.

[0030] In the embodiment, the first industrial waste salt can be added in an amount determined by the calcium ion content in the waste incineration fly ash washing solution (generally, the calcium ion content in the waste incineration fly ash washing solution is not more than 5 mg / L), and the second industrial waste salt can be added in an amount determined by the chloride ion content in the mixed solution (generally, the calcium ion content in the solution is not less than 4.74 mol / L) to ensure that the calcium ion concentration in the mixed solution is reduced to below 5 mg / L and the concentration of the chloride salt in the mixed solution reaches saturation.

[0031] In the embodiment, the filtering assembly 2 comprises a first filtering device (not shown in the figure) and a second filtering device (not shown in the figure) connected in sequence, the first filtering device is used to filter the insoluble substances in the mixed solution, and the second filtering device is used to filter the organic substances and residual calcium ions in the mixed solution.

[0032] In the embodiment, by arranging the first filtering device and the second filtering device, the insoluble substances, the organic substances and the calcium ions in the mixed solution can be filtered respectively, that is, the impurities in the mixed solution can be removed.

[0033] In the embodiment, the second filtering device comprises a centrifugal pump, a first filtering membrane, a pressure reducing valve, a second filtering membrane and an ion exchange resin connected in sequence, the centrifugal pump is connected with the first filtering device, the ion exchange resin is connected with a heating device, the centrifugal pump is used to pressurize the mixed solution output by the first filtering device to a first preset pressure and deliver the mixed solution to the first filtering membrane, the pressure reducing valve is used to reduce the pressure of the mixed solution output by the first filtering membrane to a second preset pressure and deliver the mixed solution to the second filtering membrane, the first filtering membrane is used to filter the organic substances in the mixed solution, and the second filtering membrane and the ion exchange resin are both used to filter the calcium ions in the mixed solution.

[0034] In the embodiment, by arranging the centrifugal pump, the pressure of the mixed solution output by the first filtering device can be increased to the first preset pressure, so that the first filtering membrane is in an optimal working pressure; by arranging the first filtering membrane, the maximum operating temperature of the first filtering membrane can be adjusted to 50℃, and the maximum molecular weight is allowed to be 100, so that the first filtering membrane can effectively remove the organic substances in the mixed solution; by arranging the pressure reducing valve, the pressure of the mixed solution output by the first filtering membrane can be reduced to the second preset pressure, so that the second filtering membrane is in an optimal working pressure; by arranging the second filtering membrane, the mixed solution output by the first filtering membrane can be further removed of the organic substances and the calcium ions; by arranging the ion exchange resin, the mixed solution after the second filtering membrane can be adsorbed, so that the calcium ion content in the mixed solution is at a lower level, and the organic substances in the mixed solution can also be further removed.

[0035] In one embodiment of the present application, the mixing temperature of the mixed solution is 50-70 DEG C, the temperature of the mixed solution entering the centrifugal pump is 40-50 DEG C, the first preset pressure is 2.2-2.8 MPa, the second preset pressure is 0.2-0.4 MPa, the concentration of organic matter in the mixed solution filtered by the second filter membrane is not more than 0.5 mg / L, the concentration of calcium ions is not more than 0.2 mg / L, the concentration of calcium ions in the mixed solution filtered by the ion exchange resin is not more than 0.02 mg / L, and the concentration of chloride ions is not less than 4.74 mol / L.

[0036] In the present embodiment, the mixing temperature of the mixed solution is 50-70 DEG C, which can ensure the dissolution effect of the waste incineration fly ash washing solution on the first industrial waste salt; the temperature of the mixed solution entering the centrifugal pump is 40-50 DEG C, and the first preset pressure is 2.2-2.8 MPa, which can ensure that the first filter membrane is in an optimal working environment to improve the filtering effect of the first filter membrane.

[0037] In some embodiments, the mixing temperature of the mixed solution can be 60 DEG C, the temperature of the mixed solution entering the centrifugal pump can be 45 DEG C, the first preset pressure can be 2.5 MPa, and the second preset pressure can be 0.3 MPa.

[0038] In one embodiment of the present application, the heating device 3 uses a high-temperature steam evaporation method, and the heating device 3 includes a first heater (not shown in the figure), a second heater (not shown in the figure), and a third heater (not shown in the figure) connected in sequence and gradually decreasing in pressure, and the high-temperature steam flows through the first heater, the second heater, and the third heater in sequence. In this way, the pressure difference between the heaters can be used to transport the high-temperature steam to the next stage, thereby saving energy consumption during high-temperature steam transportation.

[0039] In one embodiment of the present application, a condensing device 5 is further included, which is connected with the heating device 3 and used to condense the steam generated by the heating device 3 to obtain condensed water; wherein the condensed water is recycled and used for washing the waste incineration fly ash.

[0040] In the present embodiment, by arranging the condensing device 5, the steam generated by the heating device 3 can be condensed and recycled, thereby realizing the recycling of water resources.

[0041] In one embodiment of the present application, a cooling device 6 is further included, which is connected with the heating device 3 and used to cool the mixed solution output by the heating device 3 so that the temperature of the mixed solution is cooled to 80-90 DEG C.

[0042] In the present embodiment, by arranging the cooling device 6, the temperature of the mixed solution entering the electrolysis device 4 can be ensured to be 80-90 DEG C, thereby ensuring the efficiency of electrolysis.

[0043] In some embodiments, the temperature of the mixed solution can be cooled to 85°C.

[0044] In one embodiment of the present application, the hydrogen obtained by the electrolysis device 4 is used for combustion to transfer the heat generated by the combustion to the heating device 3; the condensing device 5 and the cooling device 6 are connected with the mixing device 1 respectively to transfer the heat released by the condensing and cooling to the mixing device 1.

[0045] In this embodiment, by burning the hydrogen obtained by the electrolysis device 4, the heat generated by the combustion of the hydrogen can be effectively utilized, thereby realizing the recycling of material energy.

[0046] In this embodiment, the chlorine obtained by the electrolysis device 4 is used to be introduced into the mixing device 1 to remove the organic matter in the mixed solution by using the hypochlorous acid generated by the chlorine and the mixed solution in the mixing device 1; part of the sodium-rich lye obtained by the electrolysis device 4 is used to be refluxed into the cathode of the electrolysis device 4 after being diluted, wherein the concentration of the diluted sodium-rich lye is 29-30%.

[0047] In this embodiment, by introducing the chlorine obtained by the electrolysis device 4 into the mixing device 1, the subsequent generated hypochlorous acid can be used to further remove the organic matter in the mixed solution; by refluxing part of the diluted sodium-rich lye into the cathode of the electrolysis device 4, the efficiency of the electrolysis can be further ensured. In addition, the remaining part of the sodium-rich lye can be used as a reagent in the deacidification process.

[0048] It should be noted that the mixing device 1, the filtering assembly 2, the heating device 3, the electrolysis device 4, the condensing device 5 and the cooling device 6 are all known to those skilled in the art, and their specific principles and structures will not be described and limited here, as long as they can realize the functions of the devices.

[0049] In addition, as shown in Figure 2 The present application also provides a method for co-processing phosphorus-containing industrial waste salt and fly ash water washing liquid, which is applied to the system mentioned in any of the above embodiments and comprises the following steps:

[0050] Step 100: using the mixing device to contain a mixed solution of garbage incineration fly ash water washing liquid and first industrial waste salt containing inorganic phosphorus;

[0051] Step 102: using the filtering assembly to filter the insoluble substances and organic matter in the mixed solution;

[0052] Step 104: using the heating device to heat the mixed solution output by the filtering assembly to evaporate and concentrate the mixed solution;

[0053] In step 106, the mixed solution after evaporation and concentration is electrolyzed by an electrolysis device to obtain chlorine, hydrogen, dilute brine and sodium-rich lye.

[0054] It can be understood that the method embodiments and the system embodiments provided by the present application are based on the same inventive concept, and have the same beneficial effects. Therefore, the beneficial effects of the method embodiments will not be described here.

[0055] It should be noted that in the present application, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device.

[0056] Finally, it should be noted that the above description is only the preferred embodiments of the present application, and is only used to illustrate the technical solutions of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A system for co-disposal of phosphorous-containing industrial waste salt with fly ash water wash liquor, characterized in that, The device comprises a mixing device, a filtering assembly, a heating device, a cooling device and an electrolysis device connected in sequence, the mixing device is used for containing a mixed solution of waste incineration fly ash water washing liquid and a first industrial waste salt containing inorganic phosphorus, the filtering assembly is used for filtering insoluble substances, organic matters and calcium ions in the mixed solution, the insoluble substances include solid suspensions and calcium phosphate precipitates obtained by the reaction of calcium ions in the water washing liquid and phosphate ions in the mixed solution, the heating device is used for heating the mixed solution output by the filtering assembly to evaporate and concentrate the mixed solution, the cooling device is used for cooling the mixed solution output by the heating device to cool the temperature of the mixed solution to 80-90 DEG C, and the electrolysis device is used for electrolyzing the cooled mixed solution to obtain chlorine, hydrogen, dilute brine and sodium-rich lye, the chlorine obtained by the electrolysis device is used for being introduced into the mixing device to remove the organic matters in the mixed solution by using hypochlorous acid generated by the chlorine and the mixed solution in the mixing device, and part of the sodium-rich lye obtained by the electrolysis device is used for being returned into the cathode of the electrolysis device after being diluted, and the concentration of the diluted sodium-rich lye is 29-30%. The filtering assembly comprises a first filtering device and a second filtering device connected in sequence, the first filtering device is used for filtering the insoluble substances in the mixed solution, and the second filtering device is used for filtering the organic matters and residual calcium ions in the mixed solution. The second filtering device comprises a centrifugal pump, a first filtering membrane, a pressure reducing valve, a second filtering membrane and an ion exchange resin connected in sequence, the centrifugal pump is connected with the first filtering device, the ion exchange resin is connected with the heating device, the centrifugal pump is used for pressurizing the mixed solution output by the first filtering device to a first preset pressure and conveying the mixed solution to the first filtering membrane, the pressure reducing valve is used for reducing the pressure of the mixed solution output by the first filtering membrane to a second preset pressure and conveying the mixed solution to the second filtering membrane, the first filtering membrane is used for filtering the organic matters in the mixed solution, and the second filtering membrane and the ion exchange resin are both used for filtering the calcium ions in the mixed solution. The first preset pressure is 2.2-2.8 MPa, the second preset pressure is 0.2-0.4 MPa, the first industrial waste salt includes phosphorus-containing medical waste salt, sodium sulfate type medical waste salt and dimethyl aniline organic matter, the first industrial waste salt is a solid waste salt, the content of calcium ions in the waste incineration fly ash water washing liquid is not more than 5 mg / L, the content of chloride ions in the mixed solution is not less than 4.74 mol / L, so that when the concentration of calcium ions in the mixed solution is reduced to below 5 mg / L, the concentration of chloride salt in the mixed solution reaches saturation, the concentration of organic matters in the mixed solution filtered by the second filtering membrane is not more than 0.5 mg / L, and the concentration of calcium ions is not more than 0.2 mg / L.

2. The system of claim 1, wherein, The mixing temperature of the mixed solution is 50-70 DEG C, and the temperature of the mixed solution entering the centrifugal pump is 40-50 DEG C.

3. The system of claim 2, wherein, The heating device adopts a high-temperature steam evaporation mode, and comprises a first heater, a second heater and a third heater connected in sequence and gradually decreasing in pressure, and the high-temperature steam flows through the first heater, the second heater and the third heater in sequence.

4. The system of claim 3, wherein, The condensing device is further included and connected with the heating device, and used for condensing the steam generated by the heating of the heating device to obtain condensed water; wherein the condensed water is used for water washing of the waste incineration fly ash.

5. The system of claim 4, wherein, The hydrogen obtained by the electrolysis device is used for combustion to transfer the heat generated by combustion to the high-temperature steam; and the condensing device and the cooling device are respectively connected with the mixing device to transfer the heat released by condensation and cooling to the mixing device.

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