CN112999674A - Apparatus and method for removing chloride ions from ammonia desulfurization solution - Google Patents
Apparatus and method for removing chloride ions from ammonia desulfurization solution Download PDFInfo
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- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/48—Sulfur compounds
- B01D53/50—Sulfur oxides
- B01D53/501—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound
- B01D53/502—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound characterised by a specific solution or suspension
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Abstract
The invention relates to a device and a corresponding method for removing chloride ions from an ammonia desulphurization solution. The apparatus includes an evaporative crystallization system configured to receive an ammonia desulfurization solution containing chloride ions, concentrate the ammonia desulfurization solution into a slurry by evaporative crystallization, and output the slurry having a predetermined solids content. The apparatus further includes a spray dryer, wherein a first portion of a mother liquor produced from the output slurry can be returned to the evaporative crystallization system and a second portion of the mother liquor can be delivered to the spray dryer, the spray dryer configured for spray drying the second portion of the mother liquor into a solid product. The operation cost can be reduced and the powder proportion can be reduced by the combined process.
Description
Technical Field
The invention belongs to the technical field of environment-friendly equipment, and particularly relates to equipment and a method for removing chloride ions from an ammonia desulphurization solution.
Background
At present, one of the mainstream processes for removing sulfur dioxide from flue gas can be limestone-gypsum method, which generates a large amount of waste water and gypsum slag during the desulfurization process, wherein about 0.7 ton of carbon dioxide can be synchronously generated for every 1 ton of sulfur dioxide removal. The treatment of such waste water and slag requires a large amount of investment and running costs. Another process can be ammonia desulphurization, wherein wastewater and waste residues are not basically generated, and the added desulfurizer ammonia can be converted into ammonium sulfate fertilizer, thereby changing waste into valuable. Typically, the sales revenue of ammonium sulfate fertilizers can be greater than the input cost of the desulfurizing agent ammonia. Typically, the flue gas to be desulfurized may contain a certain amount of chloride ions, and most of the chloride ions in the flue gas are also washed off simultaneously during the washing desulfurization to form an ammonium chloride solution. In addition, the make-up water and the desulfurizer ammonia may also carry chloride ions. Typically, ammonia desulfurization can be a non-wastewater process, wherein chloride ions entering the ammonia desulfurization system are discharged with ammonium sulfate. When the concentration of chloride ions entering the ammonia desulfurization system is high, high concentrations of chloride ions can accumulate in the ammonia desulfurization solution. The high concentration of chloride ions accumulated in the ammonia desulfurization system can cause corrosion of the equipment, affecting the long-term stable operation of the equipment. For example, in a boiler flue gas desulfurization system, ammonium sulfate solution generated by ammonia desulfurization can be evaporated and crystallized in a desulfurization tower by using flue gas waste heat to generate slurry, and after the slurry is subjected to solid-liquid separation, mother liquor returns to the desulfurization tower to continue to be evaporated and crystallized. This can cause the accumulation of chloride ions in the desulfurization tower, and the concentration of the accumulated chloride ions can even reach over 10 ten thousand ppm, which can cause corrosion to the ammonia desulfurization system and even cause abnormal work. In the evaporative crystallization process outside the desulfurization tower, the mother liquor resulting from the solid-liquid separation is not returned to the desulfurization tower, which can suppress the accumulation of chloride ions in the desulfurization tower, but causes a problem of the accumulation of chloride ions in the evaporative crystallization system. In addition, the ammonia desulfurization solution may also contain other impurities, and the accumulation of the impurities may cause the boiling point to rise and the solution to become sticky, thereby influencing the effective performance of evaporative crystallization.
Patent document CN103949155B discloses an evaporative crystallization apparatus for ammonia desulfurization solution, in which slurry discharged from an evaporative crystallization system is subjected to solid-liquid separation, and the separated mother liquor is completely evaporated and crystallized directly by a rake vacuum evaporation dryer. The device has the advantages of high investment, high energy consumption and high operation difficulty.
Patent document CN104016535B discloses an evaporative crystallization apparatus for ammonia desulfurization solution, wherein multistage evaporative crystallization is employed. The multistage evaporative crystallization process has long flow and high operation energy consumption, and along with the continuous proceeding of evaporative crystallization, impurities in the solution can be continuously accumulated, so that the boiling point can be increased, the viscosity is increased, and the evaporative crystallization cannot be effectively operated.
Patent document CN108558098A discloses a treatment device for calcium desulfurization wastewater, wherein a combined process of pretreatment, two-stage MVR (mechanical vapor recompression) evaporative crystallization, single-effect evaporation and spray drying is adopted. The combined process has complex structure and high energy consumption, and can not be used in ammonia desulphurization.
Patent document CN203090503U discloses a treatment apparatus for ammonia desulfurization solution, which includes a spray drying apparatus, wherein the ammonia desulfurization solution is directly treated with the spray drying apparatus. The device has high operation energy consumption, small particle size of product particles and easy generation of dust pollution.
Patent document CN112275111A discloses an apparatus for processing ammonia desulfurization solution by MVR evaporative crystallization, wherein ammonium sulfate solution generated in a desulfurization tower is conveyed to an MVR evaporative crystallization system by a pump, the ammonium sulfate solution is continuously concentrated into slurry during evaporation, and the slurry is pumped into a centrifugal separation system for solid-liquid separation when the solid content in the slurry reaches 10% to 20%. In the device, with the continuous progress of evaporative crystallization, chloride ions and other impurities in the slurry can be accumulated continuously, which can cause the boiling point of the slurry to rise and the viscosity to become large, so that the MVR evaporative crystallization cannot be operated effectively.
Disclosure of Invention
The object of the invention is to provide a device and a method for removing chloride ions from ammonia desulfurization solutions, by means of which chloride ions can be removed efficiently, with low energy consumption and cost-effectively and the evaporative crystallization system can be operated stably for a long period.
A first aspect of the invention provides an apparatus for removing chloride ions from an ammonia desulfurization solution, the apparatus comprising an evaporative crystallization system configured to receive the chloride ion-containing ammonia desulfurization solution, concentrate the ammonia desulfurization solution into a slurry by evaporative crystallization, and output the slurry with a predetermined solids content, and further comprising a spray dryer, wherein a first portion of a mother liquor produced from the slurry output from the evaporative crystallization system can be returned to the evaporative crystallization system and a second portion of the mother liquor can be delivered to the spray dryer, the spray dryer configured to spray dry a second portion of the mother liquor into a solid product.
A combined evaporative crystallization and spray drying process can be used in the apparatus outside the desulfurization tower, which can effectively and cost-effectively remove chloride ions with low energy consumption, and substantially eliminate the problems caused by the continuous accumulation of chloride ions in the evaporative crystallization system, which can be operated stably for a long period. Further, the powder obtained by spray drying may be contained in a suitable range in the total product.
In the process of evaporative crystallization, water is evaporated, so that chloride ions in the solution or slurry are concentrated and enriched. For example, a portion of the chloride ions can be co-crystallized with ammonium sulfate in the form of ammonium chloride, can be separated and discharged together with ammonium sulfate as a solid wet material. The mother liquor enriched in chloride ions can be partly conveyed to a spray dryer, whereby chloride ions can additionally be removed.
In some embodiments, the apparatus may include a solid-liquid separation device configured to perform solid-liquid separation on the slurry output from the evaporative crystallization system. The solid-liquid separation device can improve the production efficiency of equipment and reduce the production energy consumption.
In some embodiments, the apparatus may include a mother liquor tank to which mother liquor separated by the solid-liquid separation device can be fed, which may have a conduit to the evaporative crystallization system and a conduit to the spray dryer.
In some embodiments, the solid-liquid separation device may comprise one or more of a cyclone, a centrifuge, a belt filter, and a thickener. Advantageously, the solid-liquid separation device may comprise a cyclone configured for concentrating the slurry output from the evaporative crystallization system and a centrifuge downstream of the cyclone, the centrifuge mechanism being configured for solid-liquid separation of the concentrated slurry. Therefore, the solid-liquid separation of the slurry can be realized with high efficiency and low energy consumption.
In some embodiments, the apparatus may include a cooling crystallization device, whereby the slurry output from the evaporative crystallization system may be cooled. Here, by utilizing the characteristic that the saturated solubility of ammonium chloride greatly changes with temperature, ammonium chloride can be further crystallized and precipitated from the slurry by cooling. This may facilitate the removal of chloride ions.
Advantageously, the cooling crystallization device may be disposed between the evaporative crystallization system and the solid-liquid separation device.
In some embodiments, the cooling crystallization device can be configured to cool the slurry output from the evaporative crystallization system by 10-30 ℃ and/or 40-70 ℃, for example, 15-25 ℃ or 50-60 ℃.
In some embodiments, the apparatus may include a wet-feed dryer configured to dry a solid wet feed produced from the slurry output from the evaporative crystallization system into a solid product. The wet-goods dryer can be constructed independently of the spray dryer or integrated with one another.
Advantageously, the spray dryer and the wet goods dryer can be designed in one piece, the spray dryer being located above the wet goods dryer, the solid product produced by the spray dryer and the solid product produced by the wet goods dryer being able to be discharged via a common outlet.
Advantageously, the spray dryer and the wet-goods dryer can both use hot air as drying medium, the used hot air being discharged after dust removal.
In some embodiments, the second portion of the mother liquor may be less than the first portion of the mother liquor.
In some embodiments, the evaporative crystallization system may be designed as a single-effect evaporative crystallization system, a multiple-effect evaporative crystallization system, or a MVR evaporative crystallization system.
In some embodiments, the evaporative crystallization system may have a heater and an evaporative separation chamber and a circulation pump configured to create a feed circulation from the evaporative separation chamber to the heater via the circulation pump and then back to the evaporative separation chamber, a first portion of fresh ammonia desulfurization solution and mother liquor can be added to the feed circulation upstream of the heater, and the feed heated by the heater can be flash separated in the evaporative separation chamber.
In some embodiments, fresh ammonia desulfurization solution can be added to the feed circulation downstream of the circulation pump, and a first portion of the mother liquor can be added to the feed circulation upstream of the circulation pump.
In some embodiments, the heater may use live steam and/or compressed steam from a compressor generated by an evaporative separation chamber as a working medium.
In some embodiments, the heater may use the vapor produced by the evaporation and separation chamber and compressed by the compressor as a working medium for which the apparatus may include a condensing device downstream of the heater and a vacuum pump downstream of the condensing device.
In some embodiments, the heater can be operated with live steam, and the device is a steam discharge from the evaporation and separation chamber equipped with a condensation device and a vacuum pump downstream of the condensation device.
In some embodiments, the evaporative crystallization system may have at least one of the following operating parameters:
the temperature of the slurry in the evaporation separation chamber is 50-95 ℃, particularly 60-80 ℃, for example 65-75 ℃;
the predetermined solids content of the slurry in the evaporative separation chamber is 5 to 30%, particularly 10 to 25%, for example 15 to 20%;
the vacuum degree in the evaporation separation chamber is 10-95 kPa, particularly 15-80 kPa, such as 30-70 kPa;
the temperature difference between the gas phase and the liquid phase in the evaporation separation chamber is less than 40 ℃, in particular less than 30 ℃, for example less than 20 ℃.
Herein, the ammonium sulfate concentration and the solid content of the slurry are expressed in mass percent, respectively.
A second aspect of the invention provides a method for removing chloride ions from an ammonia desulfurization solution, the method comprising:
conveying the ammonia desulfurization solution containing chloride ions to an evaporative crystallization system, and concentrating the solution into slurry through evaporative crystallization;
outputting a slurry having a predetermined solids content;
returning a first portion of a mother liquor produced from the output slurry to the evaporative crystallization system and conveying a second portion of the mother liquor to the spray dryer; and is
The second portion of the mother liquor is spray dried to a solid product using a spray dryer.
In some embodiments, the method may be carried out using an apparatus for removing chloride ions from an ammonia desulfurization solution according to the first aspect of the present invention.
In some embodiments, the temperature of the slurry in the evaporation separation chamber is controlled to be 50-95 ℃, the temperature difference between a gas phase and a liquid phase in the evaporation separation chamber is less than 40 ℃, the vacuum degree in the evaporation separation chamber is controlled to be 10-95 kPa, and the solid content of the slurry in the evaporation separation chamber is 5-30%. Preferably, the slurry output from the evaporative crystallization system is cooled to 40-70 ℃ and then subjected to solid-liquid separation through a solid-liquid separation device, the separated solid wet material is conveyed to a wet material dryer to be dried into a solid product, and the second part of the separated mother liquor is conveyed to a spray dryer to be dried into a solid product. Preferably, the spray dryer and the wet goods dryer are designed in one piece and each use hot air as the working medium, and the solid product produced by the spray dryer and the solid product produced by the wet goods dryer are output to the packaging machine via a common outlet.
The features already mentioned above, those to be mentioned below and those available in the drawings can be combined with one another as desired, provided that the combined features are not mutually inconsistent. All possible combinations of features are the subject matter of the technology described in the present application.
Drawings
The device and the method according to the invention are described below by way of example by way of embodiments with reference to the accompanying drawings. Wherein:
FIG. 1 is a schematic diagram of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a first embodiment of the present invention.
FIG. 2 is a schematic view of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a second embodiment of the present invention.
FIG. 3 is a schematic view of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a third embodiment of the present invention.
Fig. 4 is a schematic illustration of a spray dryer according to another embodiment.
Detailed Description
The same reference numbers in different drawings may identify the same or similar elements. For the sake of brevity, the description of the components of one embodiment may be conveniently transferred to components having the same reference numerals in other embodiments so as not to repeat the description.
FIG. 1 is a schematic diagram of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a first embodiment of the present invention. With the aid of which a method for removing chloride ions from an ammonia desulfurization solution can be carried out.
The apparatus comprises an evaporative crystallization system, which is designed as an MVR evaporative crystallization system, comprising an evaporative separation chamber 3 and a heater 5, and a circulation pump 21. The circulation pump 21 is configured for creating a circulation of material from the evaporation separation chamber 3 via the circulation pump 21 to the heater 5 and then back to the evaporation separation chamber 3. The fresh ammonia desulfurization solution 1 output from the desulfurization tower may be transferred to the raw material tank 2 and then added to the material circulation between the circulation pump 21 and the heater 5. The material heated by the heater 5 can be subjected to flash separation in the evaporative separation chamber 3.
The vapor in the upper portion of the vaporization separation chamber 3 is sucked and compressed by the compressor 20 so that a predetermined degree of vacuum is maintained in the vaporization separation chamber 3. The compressed vapor may have an elevated temperature as a heat source for the heater 5. After leaving the heater 5, the compressed steam is passed to a condensation device 6, which has a circulating cooling water top 9 and a circulating cooling water back 11 and an evaporation condensate outlet 8. A vacuum pump 7 is connected downstream of the condensation device 6.
The material may be circulated through the evaporative crystallization system until a slurry having a predetermined solids content is formed in which the chloride ions are concentrated and enriched, perhaps with a small amount of chloride ions having been crystallized in the form of ammonium chloride along with ammonium sulfate. Typically, the solids content of the slurry can be controlled to be 10-20%.
The slurry output from the evaporation-separation chamber 3 can first be conveyed to a cooling-crystallization device 11, which can have, for example, a water cooling system. The cooling crystallization device 11 can be configured to cool the slurry to 10-30 ℃ and/or 40-70 ℃. Further precipitation of ammonium chloride from the slurry can be achieved by cooling crystallization, since the saturated solubility of ammonium chloride has the characteristic of varying greatly with temperature. The slurry crystallized by cooling may then be sent to the solid-liquid separation device 12, the separated solid wet matter may be sent to the wet matter dryer 14a, and the separated mother liquor may be sent to the mother liquor tank 13. The mother liquor temporarily stored in the mother liquor tank 13 may be returned in a first portion to the evaporative crystallization system, for example, added to the feed circulation upstream of the circulation pump 21. The mother liquor temporarily stored in the mother liquor tank 13 may be conveyed in a second portion to the spray dryer 14b and spray dried there to a solid product. Typically, the second portion may be less than the first portion. For example, the solid-liquid separation device 12 may include a cyclone, which concentrates the slurry, for example, to have a solids content of 50%, and a centrifuge downstream of the cyclone, which then performs solid-liquid separation on the concentrated slurry. This can be particularly low energy consuming.
The spray dryer 14b and the wet matter dryer 14a may be integrally formed, for example, the spray dryer 14b is located above the wet matter dryer 14a, and the solid product produced by the spray dryer 14b and the solid product produced by the wet matter dryer 14a can be output via a common outlet to a packaging machine 19 to be packaged as an end product 4 having a predetermined mass, for example 40 or 50 kg. The spray dryer 14b can be equipped with a fan 16, the air conveyed via the fan 16 being heatable by steam and thus forming hot air for spray drying. For this purpose, the spray dryer 14b can be provided with a steam supply end 17 and a condensate return end 18. Similarly, the wet-goods dryer 14a can be equipped with a fan 26, the wind conveyed via the fan 26 being heatable by steam and thus forming hot air for drying the wet goods. For this purpose, the wet goods dryer 14a can be provided with a steam supply 27 and a condensate return 28. The used hot air may be treated via the dry tail gas dust removal device 15 and then discharged.
FIG. 2 is a schematic view of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a second embodiment of the present invention. The second embodiment differs from the first embodiment essentially in that the evaporative crystallization system is designed as a single-effect evaporative crystallization system. In other respects, reference may be made to the description for the first embodiment.
In the second embodiment, the heater 5 uses live steam as a heat source, for which purpose the heater 5 may be provided with a steam supply end 37 and a condensate return end 38. The condensing means 6 is directly connected to the upper part of the evaporation and separation chamber 3.
FIG. 3 is a schematic view of an apparatus for removing chloride ions from an ammonia desulfurization solution according to a third embodiment of the present invention. The third embodiment differs from the first and second embodiments primarily in that the evaporative crystallization system is designed as a dual effect evaporative crystallization system. In other respects, reference may be made to the description for the first and second embodiments.
In the third embodiment, the evaporative crystallization system comprises two evaporative separation chambers 3 connected in series, the material can be conveyed to the downstream two-effect evaporative separation chamber 3 after being circulated and concentrated to a predetermined degree in the upstream one-effect evaporative separation chamber 3, and the material can be conveyed to the cooling crystallization device 11 after being circulated and concentrated to a predetermined degree in the two-effect evaporative separation chamber 3. The heater 5 for the one-effect evaporation separation chamber 3 may use live steam as a heat source, and the heater 5 for the two-effect evaporation separation chamber 3 may use steam generated from the one-effect evaporation separation chamber 3 as a heat source.
In the first to third embodiments, the evaporative crystallization system may have at least one of the following operating parameters:
the temperature of the slurry in the evaporation separation chamber is 50-95 ℃, particularly 60-80 ℃, for example 65-75 ℃;
the predetermined solids content of the slurry in the evaporative separation chamber is 5 to 30%, particularly 10 to 25%, for example 15 to 20%;
the vacuum degree in the evaporation separation chamber is 10-95 kPa, particularly 15-80 kPa, such as 30-70 kPa;
the temperature difference between the gas phase and the liquid phase in the evaporation separation chamber is less than 40 ℃, in particular less than 30 ℃, for example less than 20 ℃.
Fig. 4 is a schematic illustration of a spray dryer according to another embodiment. According to this embodiment, the spray dryer 14b can be formed separately from the wet-goods dryer 14a, which is not shown.
The following describes an exemplary operation of the device according to three embodiments of the invention.
An exemplary operating situation of the device according to the first embodiment may be as follows:
the ammonia desulphurization solution containing 40000ppm of chloride ions and 46% of ammonium sulfate and having a flow rate of 3000kg/h can be sent into the evaporation separation chamber 3 through an evaporation circulation pipeline, the materials in the evaporation separation chamber 3 can be circularly heated through a circulation pump 21 and a heater 5, the heated materials enter the evaporation separation chamber 3 for flash separation to form crystallized slurry, and the gas phase is compressed by a compressor 20, then enters the heater 5 as a heat source, and is condensed. The temperature of the material in the evaporation separation chamber 3 was controlled at 70 deg.C, and the vacuum degree of the evaporation separation chamber was controlled at about 80 kPa. And a part of the slurry enters a cooling crystallization device 11, and is cooled to 45 ℃ by circulating water so as to further crystallize and separate out ammonium chloride. The slurry after cooling and crystallization enters a solid-liquid separation device 12. The solid-liquid separation device consists of a cyclone and a centrifuge in series, wherein a slurry having a solids content of about 15% first enters the cyclone and is concentrated to have a solids content of 50%. The concentrated slurry then enters a centrifuge. The wet feed from the centrifuge contains mainly ammonium sulfate and a small amount of ammonium chloride. The wet material is dried in a wet material dryer 14a, which is designed, for example, as a fluidized bed dryer. The mother liquor separated from the solid-liquid separator 12 is fed to a mother liquor tank 13, most of the mother liquor is returned to the evaporation separation chamber 3, and about 800kg/h of the mother liquor is fed to a spray dryer 14b for spray drying. The spray dryer 14b and the wet material dryer 14a both use hot air for drying, and the used dust-containing gas is discharged after dust removal. Through simulation calculation, the wet material is dried to obtain a product of 1044kg/h, wherein the ammonium sulfate is 1012kg/h, the ammonium chloride is 22kg/h, and the recovered water is 10 kg/h; 517kg/h of powder product can be obtained by spray drying, wherein the ammonium sulfate is 368kg/h, the ammonium chloride is 145kg/h, and the recycled water is 4 kg/h; the process power consumption is 110kWh/h, the steam consumption is 1135kg/h, and the circulating cooling water consumption is 7 tons/h. The unit price of electricity, steam and circulating cooling water is calculated according to 0.5 yuan/kWh, 80 yuan/ton and 0.02 yuan/ton, and the operation cost is 146 yuan/h.
An exemplary operating situation of the device according to the second embodiment can be as follows:
the ammonia desulphurization solution containing 40000ppm of chloride ions and 46% of ammonium sulfate and having a flow rate of 3000kg/h is sent into the evaporation separation chamber 3 through an evaporation circulation pipeline, the materials in the evaporation separation chamber are circularly heated through a circulation pump and a heater, the heated materials enter the evaporation separation chamber 3 for flash separation to form crystallized slurry, and the gas phase enters a condenser for condensation. The temperature of the material in the separation chamber was controlled at 70 deg.C and the vacuum in the separation chamber was controlled at 80kPa (about 20kPa abs.). And (3) allowing part of the slurry to enter a cooling crystallization device 11, and cooling to 45 ℃ by using circulating water to further crystallize and separate out ammonium chloride. The slurry after cooling and crystallization enters a solid-liquid separation device 12. The solid-liquid separation device consists of a cyclone and a centrifuge in series, wherein a slurry with a solids content of 25% is first fed to the cyclone so that the slurry is concentrated to have a solids content of 50% and the concentrated slurry is fed to the centrifuge. The wet material from the centrifuge is passed to a wet material dryer 14a for drying. The mother liquor separated from the solid-liquid separation device 12 is fed to a mother liquor tank 13, wherein most of the mother liquor is returned to the evaporation separation chamber 3, and about 800kg/h of the mother liquor is fed to a spray dryer 14b for spray drying. The spray dryer and the wet material dryer both adopt hot air drying. Through simulation calculation, the wet material is dried to obtain a product of 1044kg/h, wherein the ammonium sulfate is 1012kg/h, the ammonium chloride is 22kg/h, and the recovered water is 10 kg/h; 517kg/h of powder product can be obtained by spray drying, wherein the ammonium sulfate is 368kg/h, the ammonium chloride is 145kg/h, and the recycled water is 4 kg/h; the process power consumption is 54kWh/h, the steam consumption is 2758kg/h, and the circulating cooling water consumption is 69 tons/h. The unit price of electricity, steam and circulating cooling water is calculated according to 0.5 yuan/kWh, 80 yuan/ton and 0.02 yuan/ton, and the operation cost is 249 yuan/h.
An exemplary operating situation of the device according to the third embodiment can be as follows:
the ammonia desulphurization solution containing 40000ppm of chloride ions and 46% of ammonium sulfate and having a flow rate of 3000kg/h is sent into the one-effect evaporation separation chamber 3 through an evaporation circulation pipeline, the materials in the one-effect evaporation separation chamber 3 are circularly heated through a circulating pump and a heater, and the heated materials enter the one-effect evaporation separation chamber 3 for flash separation to form crystallized slurry. The material from the first-effect evaporation separation chamber 3 enters the second-effect evaporation separation chamber 3. The gas phase from the single-effect evaporation separation chamber 3 enters a double-effect heater 5. The slurry from the double-effect evaporation separation chamber 3 enters a cooling crystallization device 12, and the gas phase from the double-effect evaporation separation chamber enters a condenser to be condensed. The temperature of each evaporation separation chamber was controlled at 70 ℃ and the pressure at 20 kPa. The slurry from the double-effect evaporation separation chamber enters a cooling crystallization device 11, and is cooled to 45 ℃ by circulating water so as to further crystallize and separate out ammonium chloride. The slurry after cooling and crystallization enters a solid-liquid separation device 12. The solid-liquid separation device consists of a cyclone and a centrifuge in series, wherein a slurry with a solids content of 25% first enters the cyclone, is concentrated to a solids content of 50% and then enters the centrifuge. And (4) drying the wet material from the centrifuge in a fluidized bed dryer. The mother liquor separated from the solid-liquid separation apparatus is fed to a mother liquor tank 13, wherein most of the mother liquor is returned to the single-effect evaporation separation chamber 3, and about 800kg/h of the mother liquor is fed to a spray dryer 14b for spray drying. The spray dryer and the wet material dryer both adopt hot air drying. Through simulation calculation, the wet material is dried to obtain a product of 1044kg/h, wherein the ammonium sulfate is 1012kg/h, the ammonium chloride is 22kg/h, and the recovered water is 10 kg/h; 517kg/h of powder product can be obtained by spray drying, wherein the ammonium sulfate is 368kg/h, the ammonium chloride is 145kg/h, and the recycled water is 4 kg/h; the process power consumption is 58kWh/h, the steam consumption is 1780kg/h, and the circulating cooling water consumption is 35 tons/h. The unit price of electricity, steam and circulating cooling water is calculated according to 0.5 yuan/kWh, 80 yuan/ton and 0.02 yuan/ton, and the running cost is 172 yuan/h.
As a comparative example with the present invention, an ammonia desulfurization solution containing 40000ppm of chloride ions and 46% of ammonium sulfate at a flow rate of 3000kg/h was directly fed to a spray dryer to be spray-dried. 1561kg/h of powder product can be obtained by simulation calculation and spray drying, wherein 1380 kg/h of ammonium sulfate, 167kg/h of ammonium chloride and 14kg/h of recycled water; the process power consumption is 123kWh/h, and the steam consumption is 4358 kg/h. The operating cost is 410 yuan/h, assuming that the unit price of electricity and steam is calculated as 0.5 yuan/kWh and 80 yuan/ton.
While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are merely illustrative and do not limit the scope of the invention. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.
Claims (10)
1. An apparatus for removing chloride ions from an ammonia desulfurization solution, the apparatus comprising an evaporative crystallization system configured to receive the chloride ion-containing ammonia desulfurization solution, concentrate the ammonia desulfurization solution into a slurry by evaporative crystallization, and output the slurry with a predetermined solids content, characterized in that the apparatus further comprises a spray dryer (14b), wherein a first portion of a mother liquor produced from the slurry output from the evaporative crystallization system can be returned to the evaporative crystallization system and a second portion of the mother liquor can be conveyed to the spray dryer, the spray dryer configured to spray dry a second portion of the mother liquor into a solid product.
2. The apparatus for removal of chloride ions from an ammonia desulfurization solution according to claim 1, characterized in that the apparatus comprises a solid-liquid separation device (12) configured for solid-liquid separation of the slurry output from the evaporative crystallization system, wherein the separated mother liquor can be sent to a mother liquor tank (13) having a conduit to the evaporative crystallization system and a conduit to the spray dryer;
preferably, the solid-liquid separation device comprises one or more of a cyclone, a centrifuge, a belt filter and a thickener;
in particular, the solid-liquid separation device comprises a cyclone and a centrifuge downstream of the cyclone, wherein the cyclone is configured for concentrating the slurry output from the evaporative crystallization system, and the centrifugation mechanism is configured for solid-liquid separation of the concentrated slurry;
preferably, the equipment comprises a cooling crystallization device (11) arranged between the evaporative crystallization system and the solid-liquid separation device, wherein the cooling crystallization device is configured to cool slurry output from the evaporative crystallization system so as to separate out solids from the slurry;
preferably, the cooling crystallization device is configured to cool the output slurry to 10-30 ℃ and/or 40-70 ℃.
3. The apparatus for removing chloride ions from an ammonia desulfurization solution according to any one of claims 1 to 2, characterized in that the apparatus comprises a wet-stock dryer (14a) configured for drying a solid wet stock produced from a slurry output from the evaporative crystallization system into a solid product;
preferably, the spray dryer and the wet-goods dryer are integrally formed, the spray dryer being located above the wet-goods dryer, the solid product produced by the spray dryer and the solid product produced by the wet-goods dryer being able to be output via a common outlet;
preferably, the spray dryer and the wet material dryer both use hot air as a drying medium, and the used hot air is discharged after dust removal.
4. The apparatus for removing chloride ions from an ammonia desulfurization solution of any one of claims 1 to 3, wherein the second portion of the mother liquor is less than the first portion of the mother liquor; and/or
The evaporative crystallization system is designed into a single-effect evaporative crystallization system, a multi-effect evaporative crystallization system or an MVR evaporative crystallization system.
5. The apparatus for removing chloride ions from an ammonia desulfurization solution according to any one of claims 1 to 4, characterized in that the evaporative crystallization system has a heater (5) and an evaporative separation chamber (3) and a circulation pump (21) configured for creating a circulation of material from the evaporative separation chamber to the heater via the circulation pump and then back to the evaporative separation chamber, into which circulation of material a first portion of fresh ammonia desulfurization solution and mother liquor can be added upstream of the heater, in which evaporation separation chamber the material heated by the heater can be subjected to flash separation;
preferably, fresh ammonia desulfurization solution can be added to the feed circulation downstream of the circulation pump, and a first portion of the mother liquor can be added to the feed circulation upstream of the circulation pump;
preferably, the heater takes fresh steam and/or steam generated by an evaporation separation chamber and compressed by a compressor as a working medium;
preferably, the heater uses the vapor produced by the evaporation and separation chamber and compressed by the compressor as a working medium for which the apparatus comprises a condensing device downstream of the heater and a vacuum pump downstream of the condensing device;
preferably, the heater uses live steam as a working medium, and the device is such that the steam leaving the evaporation and separation chamber is provided with a condensing device and a vacuum pump downstream of the condensing device.
6. The apparatus for removing chloride ions from an ammonia desulfurization solution of claim 5, wherein the evaporative crystallization system has at least one of the following operating parameters:
the temperature of the slurry in the evaporation separation chamber is 50-95 ℃, particularly 60-80 ℃;
the predetermined solids content of the slurry in the evaporative separation chamber is 5 to 30%, particularly 10 to 25%, for example 15 to 20%;
the vacuum degree in the evaporation separation chamber is 10-95 kPa, particularly 15-80 kPa, such as 30-70 kPa;
the temperature difference between the gas phase and the liquid phase in the evaporation separation chamber is less than 40 ℃, in particular less than 30 ℃.
7. A method for removing chloride ions from an ammonia desulfurization solution, the method comprising:
conveying the ammonia desulfurization solution containing chloride ions to an evaporative crystallization system, and concentrating the solution into slurry through evaporative crystallization;
outputting a slurry having a predetermined solids content;
returning a first portion of a mother liquor produced from the output slurry to the evaporative crystallization system and conveying a second portion of the mother liquor to the spray dryer; and is
The second portion of the mother liquor is spray dried to a solid product using a spray dryer.
8. The method for removing chloride ions from an ammonia desulfurization solution according to claim 7, characterized in that the method is carried out with an apparatus for removing chloride ions from an ammonia desulfurization solution according to any one of claims 1 to 6.
9. The method for removing chloride ions from an ammonia desulfurization solution of claim 8, characterized in that the method has at least one of the following technical features:
controlling the temperature of the slurry in the evaporation separation chamber to be 50-95 ℃;
the temperature difference between the gas phase and the liquid phase in the evaporation separation chamber is less than 40 ℃;
controlling the vacuum degree in the evaporation separation chamber to be 10-95 kPa;
the solid content of the slurry in the evaporation separation chamber is 5-30%.
10. The method for removing chloride ions from ammonia desulphurization solution according to claim 9, characterized in that the slurry output from the evaporative crystallization system is cooled to 40-70 ℃ and then subjected to solid-liquid separation via a solid-liquid separation device, the separated solid wet material is conveyed to a wet material dryer to be dried into a solid product, and the second part of the separated mother liquor is conveyed to a spray dryer to be dried into a solid product; and/or
The spray dryer and the wet goods dryer are integrally formed and each use hot air as a working medium, and the solid product produced by the spray dryer and the solid product produced by the wet goods dryer are output to the packaging machine via a common outlet.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113440878A (en) * | 2021-07-02 | 2021-09-28 | 江苏新世纪江南环保股份有限公司 | Apparatus and method for removing chloride ions in ammonia desulfurization |
| CN117049718A (en) * | 2023-06-28 | 2023-11-14 | 北京清新环境技术股份有限公司 | Method for removing chloride ions from desulfurization slurry |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1631782A (en) * | 2004-12-17 | 2005-06-29 | 王明祥 | Method for extracting ammonia sulfate from resultant of flue gas desulfurization by ammonia method |
| CN203090503U (en) * | 2013-03-19 | 2013-07-31 | 南京圣诺热管有限公司 | Ammonia desulphurization crystalline liquid processing unit |
| CN103949155A (en) * | 2014-05-13 | 2014-07-30 | 武汉钢铁(集团)公司 | Ammonia process desulfurization evaporative crystallization process and ammonia process desulfurization evaporative crystallization device for reducing concentration of Cl<-> |
| EP3461803A1 (en) * | 2017-10-02 | 2019-04-03 | Evonik Degussa GmbH | Method for the production of granules containing dipeptide |
| CN210021191U (en) * | 2018-12-12 | 2020-02-07 | 南京新世纪江南环保科技发展有限公司 | Evaporative crystallization device applied to ammonia desulphurization device |
| CN112275111A (en) * | 2020-11-30 | 2021-01-29 | 昆岳互联环境技术(江苏)有限公司 | Device and method for removing chloride ions in ammonia desulfurization slurry through MVR evaporation crystallization |
-
2021
- 2021-02-25 CN CN202110210613.8A patent/CN112999674A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1631782A (en) * | 2004-12-17 | 2005-06-29 | 王明祥 | Method for extracting ammonia sulfate from resultant of flue gas desulfurization by ammonia method |
| CN203090503U (en) * | 2013-03-19 | 2013-07-31 | 南京圣诺热管有限公司 | Ammonia desulphurization crystalline liquid processing unit |
| CN103949155A (en) * | 2014-05-13 | 2014-07-30 | 武汉钢铁(集团)公司 | Ammonia process desulfurization evaporative crystallization process and ammonia process desulfurization evaporative crystallization device for reducing concentration of Cl<-> |
| EP3461803A1 (en) * | 2017-10-02 | 2019-04-03 | Evonik Degussa GmbH | Method for the production of granules containing dipeptide |
| CN210021191U (en) * | 2018-12-12 | 2020-02-07 | 南京新世纪江南环保科技发展有限公司 | Evaporative crystallization device applied to ammonia desulphurization device |
| CN112275111A (en) * | 2020-11-30 | 2021-01-29 | 昆岳互联环境技术(江苏)有限公司 | Device and method for removing chloride ions in ammonia desulfurization slurry through MVR evaporation crystallization |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113440878A (en) * | 2021-07-02 | 2021-09-28 | 江苏新世纪江南环保股份有限公司 | Apparatus and method for removing chloride ions in ammonia desulfurization |
| CN117049718A (en) * | 2023-06-28 | 2023-11-14 | 北京清新环境技术股份有限公司 | Method for removing chloride ions from desulfurization slurry |
| CN117049718B (en) * | 2023-06-28 | 2024-04-09 | 北京清新环境技术股份有限公司 | Method for removing chloride ions from desulfurization slurry |
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