CN216472254U - Sulfuric acid process titanium white powder is washed weak waste acid membrane integration resourceful treatment system once - Google Patents
Sulfuric acid process titanium white powder is washed weak waste acid membrane integration resourceful treatment system once Download PDFInfo
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- CN216472254U CN216472254U CN202123157081.0U CN202123157081U CN216472254U CN 216472254 U CN216472254 U CN 216472254U CN 202123157081 U CN202123157081 U CN 202123157081U CN 216472254 U CN216472254 U CN 216472254U
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Abstract
The utility model discloses a sulfuric acid process titanium white powder is washed rare spent acid membrane integration resourceful treatment system, include and wash useless dilute acid to titanium white powder and carry out solid-liquid separation's preliminary treatment filter equipment, set up behind the preliminary treatment filter equipment and carry out the heat exchanger of heat transfer cooling to the first filtrating that obtains through preliminary treatment filter equipment, set up behind the heat exchanger and carry out the multistage nanofiltration membrane system of receiving of straining the filtrating after the cooling, set up behind the multistage nanofiltration membrane system and strain the final nanofiltration that obtains after the membrane system is received and purify dilute acid and carry out the preconcentration system of preconcentration, the preconcentration system sets up the preconcentration sulfuric acid solution that obtains through the preconcentration system and carries out the evaporative concentration's evaporative concentration device. The utility model discloses a full physical separation device, the feature of environmental protection is good, and filter fineness is high.
Description
Technical Field
The utility model relates to a dilute spent acid processing system is washed to sulfuric acid process titanium white powder.
Background
The titanium dioxide production in China mainly adopts a sulfuric acid method production process, and the market share is over 90 percent. The production process of the titanium dioxide mainly comprises iron ore grinding → acidolysis → first washing → bleaching → second washing → salt treatment → calcination → post-treatment, wherein 30-40 tons of dilute waste acid with the concentration of 4-6% can be produced in the first washing process every 1 ton of titanium dioxide is produced, which means that 1.5-2.0 tons of sulfuric acid residue in the first washing waste acid can be produced every 1 ton of titanium dioxide is produced. In addition, the iron-based catalyst also contains 1-3% of ferrous sulfate, 1-3 g/L metatitanic acid, other small amount of light and heavy metals and the like.
The method for treating the titanium dioxide first-washing dilute waste acid is an ancient lime neutralization treatment method, has the advantages of simple operation, less equipment investment, cheap and easily available lime as a medicament and the like, but can bring a series of environmental problems, such as generation of a large amount of red gypsum, containing of various heavy metals, incapability of industrial application, only piling and burying, large floor area, weathering and rain over time, heavy metal leakage, serious pollution to downstream groundwater, potential safety hazards of nearby residents in drinking water, frequent cancer and the like; secondly, the method causes obvious waste of resources, such as sulfuric acid, TiO2, ferrous sulfate, water resources, etc., so that the method of resource treatment is urgently sought.
In recent years, due to the continuous upgrade of national treatment policies for environmental protection problems of enterprises, a large number of enterprises are promoted to meet the requirements of environmental protection policies, and in order to not affect normal production or capacity expansion and production expansion, resource water treatment methods are actively sought, for example, a membrane separation technology which is popular in recent years is a physical separation method, the membrane separation method has excellent characteristics of high filtration precision, no phase change and the like, meanwhile, membrane products with different filtration precisions (microfiltration, ultrafiltration, nanofiltration and reverse osmosis) have different application ranges, and the requirements of inlet water quality are also obviously different. For example, microfiltration and ultrafiltration generally have efficient separation and removal effects on bacteria, viruses, suspended particles, colloids, macromolecular organic matters and the like, can realize the functions of removing turbidity, separating large and small organic molecules and the like, can be used as pretreatment means of nanofiltration and reverse osmosis in the general sewage treatment process, and ensures the long-term stable operation of a nanofiltration and reverse osmosis membrane system. The filtering holes are provided with a nanofiltration membrane with the molecular weight of 150-300, so that divalent or multivalent anions and monovalent anions can be efficiently separated by more than 99%, and dissolved salt ions in water can be efficiently separated from water molecules by more than 99% like a reverse osmosis membrane with the smallest pore diameter.
Through market research and patent retrieval, the inventor finds that three or four related enterprise cases or patent applicants have already existed in which the primary washing waste acid generated in the production process of titanium dioxide is treated by a membrane integration method, the technical routes of pretreatment, nanofiltration membrane, preconcentration and evaporative concentration are generally adopted, and the following problems exist in different degrees along with different technical types adopted by each process section, so that the reliability is insufficient:
(1) pretreatment methods are not well selected, such as: insoluble hydrolyzed TiO2 remained in waste acid is colloid fine particles with strong viscosity, and a filter layer is easy to be seriously polluted, even hardened and difficult and frequent to clean by adopting solid-liquid separation equipment such as conventional sand filtration, carbon filtration and the like; the conventional coagulation and sedimentation process cannot recover pure titanium dioxide due to formation of floc inclusions, inclusion of iron ions and the like, and has high recycling difficulty; conventional hollow fiber, rolled ultrafiltration membrane assemblies, flat ultrafiltration membrane assemblies and the like can not bear strong acid environment, are generally suitable for operating at pH of 2-11, are easily polluted and blocked by viscous hydrolyzed TiO2 colloid, and have no practicability; if a ceramic membrane and TUF tubular membrane large-circulation cross-flow filtration mode is adopted, although the rapid pollution on the membrane surface caused by pollutant settlement and concentration polarization can be controlled to a certain degree, due to the colloid viscosity of hydrolyzed TiO2, the membrane pores can be rapidly polluted and blocked along with the increase of the colloid concentration, the water yield is reduced in a cliff mode, the cleaning and recovery difficulty is high, the cleaning is carried out by adopting strong acid, the requirements on equipment pipelines and membrane materials are very high, and the service life of the system and the membrane can be greatly reduced.
(2) The nanofiltration membrane system is unreasonable in design, the produced water in each section is unevenly distributed, the local concentration polarization is serious, membrane fouling and blocking are caused, the cleaning is frequent, the normal and stable production cannot be realized, the system operation pressure is high, the energy consumption is high, and the like.
(3) The pre-concentration method is not reasonable in selection, such as: the MVR process causes corrosion of a vapor compressor, and the vapor compressor cannot normally run; for example, the reverse osmosis process has the problems that the acid-resistant reverse osmosis membrane product technology is immature and the like.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an adopt sulfuric acid process titanium white powder of full physical separation device, environmental protection to wash rare spent acid membrane integration resourceful treatment system.
The technical solution of the utility model is that:
the utility model provides a dilute spent acid membrane integration resourceful treatment system is washed to sulfuric acid process titanium white powder, characterized by: the device comprises a pretreatment filtering device for performing solid-liquid separation on titanium dioxide-washing waste dilute acid, wherein a heat exchanger for exchanging heat and cooling first filtrate obtained by the pretreatment filtering device is arranged behind the pretreatment filtering device, a multi-stage nanofiltration membrane system for performing nanofiltration on the cooled filtrate is arranged behind the heat exchanger, a pre-concentration system for performing pre-concentration on final nanofiltration purified dilute acid solution obtained after nanofiltration by the multi-stage nanofiltration membrane system is arranged behind the multi-stage nanofiltration membrane system, and an evaporation concentration device for performing evaporation concentration on pre-concentrated sulfuric acid solution obtained by the pre-concentration system is arranged in the pre-concentration system.
The pretreatment filtering device comprises a filter element in a tank body, and two sides of the filter element are connected with a circulating filtering backflow pipeline; the tank body is provided with air blowing ports which are respectively positioned at two sides of the filter element.
The heat exchanger is a plate-exchange type heat exchange device, and the acid liquor overflowing part is made of strong acid resistant materials.
The multi-stage nanofiltration membrane system has two or more stages, namely, the first-stage nanofiltration purified liquid is taken as second-stage nanofiltration inlet water to obtain second-stage nanofiltration purified liquid, and the second-stage nanofiltration concentrated liquid is returned and mixed into the first-stage nanofiltration stock solution, and the rest is done in the same way; the number of stages of each stage of nanofiltration system in the multistage nanofiltration membrane system is three or more, namely, the first stage of nanofiltration water enters the first stage of membrane unit to produce concentrated water as first-stage concentrated water, the first-stage concentrated water enters the second stage of membrane unit to produce concentrated water as second-stage concentrated water, and the second-stage concentrated water enters the third stage of membrane unit to produce concentrated water as third-stage concentrated water.
The primary nanofiltration system in the multistage nanofiltration membrane system adopts a primary three-section form and adopts sectional pressurization and sectional circulating reflux, wherein the pressurization range between the first section and the second section is 0-20 bar, the pressurization range between the second section and the third section is 0-35 bar, and the circulating flow of a single-section single-branch 8-inch membrane shell is 6-16 m3/h。
The pre-concentration system is a multi-stage flash evaporation, membrane distillation or electrodialysis system.
The effect number of the evaporation concentration device is in a single-effect, double-effect, triple-effect or double-effect and single-effect combination form.
The utility model has the advantages that:
the filtration precision of the pretreatment working section can be adjusted to be below 0.1 mu m, and the requirement of inlet water quality of a subsequent nanofiltration membrane system that the inlet water SDI is less than 3 can be met. Soluble titanium salt and insoluble hydrolyzed TiO exist in titanium dioxide first-washing dilute waste acid residue2Colloids in which TiO is insoluble and hydrolyzed2As the main raw material for coating pigment, the pigment is characterized by colloidal state in solution, superfine granularity, large viscosity, strong adhesive force and the like, if the pigment is filtered by adopting conventional sand carbon filter, micro-filter and ultrafiltration membrane separation equipment, the pigment is easy to adhere and block, the backwashing recovery difficulty is large, and the chemical cleaning recovery probability is small. Adopt the utility model discloses when the technique filters titanium white powder washing weak acid pickle, can overcome the above problems of traditional solid-liquid separation and techniques such as little milipore filter, its flow is: a) firstly by using the same TiO2Circulating filtering and refluxing filter residue materials or other filter aids which do not influence the subsequent recovery of the titanium dioxide, and precoating the surface of the filter element; b) when the precoated filter cake layer reaches a certain thickness and the purity of the filtrate meets the requirement of the water quality of the inlet water required by the subsequent process, switching to a normal water production filtration state; c) when the normal water production filtration feeding pressure reaches a set upper limit value, namely the water production efficiency is reduced, and a filter cake layer reaches a certain thickness, the water production filtration is stopped, then the compressed air is used for positive blowing, dehydration and drying, and then the compressed air is used for back blowing to discharge dry slag; d) finally, washing the filter element in the reverse direction and the forward direction by using tap water; e) and entering the next cycle. The filter cake layer thickness that accessible filter aid precoating formed adjusts the size of filtration precision, can obtain the quality of water requirement of intaking that satisfies follow-up membrane system, and the operation is stable. By adopting the technology, the double effects of high-precision filtration and direct dry slag discharge can be stably realized, and the long-flow method that the high-precision pretreatment can be realized by the traditional membrane filtration method and the suspended matter concentrated solution obtained by the membrane is subjected to filter pressing, dehydration and slag discharge is broken through.
The membrane purification system adopts an acid-resistant nanofiltration membrane system with reliable quality, and iron, magnesium, calcium and other ions in waste acid can be reduced to below 1ppm at most by a nanofiltration system with two or more stages according to the process requirements; the nanofiltration system adopts a reasonable membrane design process, such as a first-stage three-section nanofiltration membrane separation unit, and adopts segmented pressurization (namely pressurizing by selectively arranging a booster pump between the previous section of concentrated water entering the next section according to the quality of the fed water, so as to ensure the uniform distribution of the produced water of each section of membrane separation treatment unit, balance the load and reduce the risk of local rapid pollution), segmented circulation (namely if a further feeding design mode is adopted, the condition of the fed flow of a certain section of membrane separation unit is calculated to be smaller, a circulating pump is required to be arranged at the feeding end of the section, so that sufficient circulating surface flow velocity is provided, the local concentration polarization and pollutant settlement on the surface of the membrane are eliminated, and the long-term stable operation of the system is ensured).
And (3) concentrating the nanofiltration purified acid from 4-6% to 12-30% by adopting a stable and reliable preconcentration system with lower cost, such as a multistage flash evaporation, membrane distillation or electrodialysis membrane preconcentration method according to technical and economic analysis. The acid concentration can be further increased to about 70 percent by multi-effect concentration of steam.
Drawings
The invention is further illustrated by the following figures and examples.
Fig. 1 is a schematic structural diagram of an embodiment of the present invention.
FIG. 2 is a schematic view of the constitution of a pretreatment filtration apparatus.
Fig. 3 is a schematic diagram of the equipment composition structure of a two-stage nanofiltration membrane system.
Detailed Description
The utility model provides an integrated resourceful treatment system of sulfuric acid method titanium white powder one washing rare spent acid membrane, include to titanium white powder one washing waste dilute acid carry out solid-liquid separation's preliminary treatment filter equipment, set up behind the preliminary treatment filter equipment and carry out the heat exchanger that the heat transfer was cooled down to the first filtrating that obtains through preliminary treatment filter equipment, set up behind the heat exchanger and carry out the multistage nanofiltration membrane system that receives filtration to the filtrating after the cooling, set up behind the multistage nanofiltration membrane system and carry out the preconcentration system that preconcentrates to the final nanofiltration purification dilute acid liquid that obtains after receiving the nanofiltration of multistage nanofiltration membrane system, preconcentration system sets up the evaporation concentration device that carries out evaporation concentration to the preconcentration sulfuric acid liquid that obtains through the preconcentration system.
The pretreatment filtering device comprises a filter element in a tank body, and two sides of the filter element are connected with a circulating filtering backflow pipeline; the tank body is provided with air blowing ports which are respectively positioned at two sides of the filter element.
The heat exchanger is a plate-exchange type heat exchange device, and the acid liquor overflowing part is made of strong acid resistant materials.
The multistage nanofiltration membrane system has two or more stages, namely, a first-stage nanofiltration purified liquid (also called as a first-stage nanofiltration permeating acid liquid) is used as second-stage nanofiltration inlet water, then a second-stage nanofiltration purified liquid (also called as a second-stage nanofiltration permeating acid liquid) is obtained, the second-stage nanofiltration concentrated liquid is returned and mixed into a first-stage nanofiltration stock solution, and the like; the number of stages of each stage of nanofiltration system in the multistage nanofiltration membrane system is three or more, namely, the first stage of nanofiltration water enters the first stage of membrane unit to produce concentrated water as first-stage concentrated water, the first-stage concentrated water enters the second stage of membrane unit to produce concentrated water as second-stage concentrated water, and the second-stage concentrated water enters the third stage of membrane unit to produce concentrated water as third-stage concentrated water.
The primary nanofiltration system in the multistage nanofiltration membrane system adopts a primary three-section form and adopts sectional pressurization and sectional circulating reflux, wherein the pressurization range between the first section and the second section is 0-20 bar, the pressurization range between the second section and the third section is 0-35 bar, and the circulating flow of a single-section single-branch 8-inch membrane shell is 6-16 m3/h。
The pre-concentration system is a multi-stage flash evaporation, membrane distillation or electrodialysis system.
The effect number of the evaporation concentration device is in a single-effect, double-effect, triple-effect or double-effect and single-effect combination form.
The working method comprises the following steps:
the specific method comprises the following steps:
waste acid components:
the method comprises the steps of firstly performing circulating filtration, backflow and precoating on a pretreatment filter with the filtration precision of 0.1 micron to form a 7.5mm filter cake layer, switching waste acid to pump into the pretreatment filter, stopping filtration when the water inlet pressure of the filter reaches 8.0bar, positively blowing by compressed air for 2min, then performing reverse blowing to discharge dry titanium dioxide slag, washing by reverse-flushing water for 1min, switching to the steps of coating a filter-aid layer, performing normal filtration and the like, repeating the steps in the cycle, normally filtering by the pretreatment filter to obtain filtrate SDI 2.0, reducing the temperature of the filtrate to 26 ℃ from 57 ℃ through a graphite heat exchanger, and entering a pretreatment filtrate collecting tank; pumping the pretreated filtrate into a first-stage three-section nanofiltration system, controlling the recovery rate of produced water to be 82%, carrying out sectional pressurization and sectional circulating reflux, controlling the initial membrane feeding pressure to be 20bar, controlling the final concentrated water pressure to be 46bar, and carrying out first-stage nanofiltration to obtain a concentrated solution and a permeate solution, wherein the water quality of the concentrated solution and the permeate solution is as follows:
the acid liquor permeating through the first-stage nanofiltration passes through a second-stage three-stage nanofiltration system, the membrane inlet pressure is controlled to be 16bar, the water yield is controlled to be 90%, and the water quality of the acid liquor permeating through the second-stage nanofiltration is shown in the following table:
the acid liquor obtained by the secondary nanofiltration is concentrated to 20% through multistage flash evaporation; the acid liquor concentrated by membrane distillation is evaporated and concentrated by double effect and single effect combination, and the concentration of the acid liquor is raised to 65%.
The first-stage nanofiltration concentrated solution is directly sold to a nearby printing and dyeing mill to be used as a water purifying agent.
The following is specifically described with reference to fig. 1:
(1) firstly pumping diluted waste acid generated in the production of titanium dioxide by a sulfuric acid method to a pretreatment filtering device 2 through a pretreatment feeding pump 1, filtering to generate pure filtrate, discharging titanium dioxide dry slag, inputting the pure filtrate into a heat exchanger 3 through a pipeline for heat exchange to obtain heat-exchanged pretreatment filtrate suitable for the water inlet temperature requirement of a subsequent two-stage nanofiltration membrane system, and then inputting the pretreatment filtrate into a pretreatment filtrate collector 4;
(2) the pretreated filtrate is pumped to a primary nanofiltration membrane treatment device 6 by a primary nanofiltration delivery pump 5, and primary nanofiltration salt concentrated solution and primary nanofiltration permeating acid solution of a dilute acid system mainly containing ferrous sulfate are obtained by the selective permeability characteristic of divalent ions of a nanofiltration membrane;
(3) a primary nano-filtration salt concentrated solution of a dilute sulfuric acid system, which mainly comprises ferrous sulfate, enters a primary nano-filtration salt concentration tank 16, passes through a salt concentrated solution delivery pump 17 and then passes through an evaporation crystallization device 18 to respectively obtain ferrous sulfate crystals and concentrated sulfuric acid mother liquor;
(4) the first stage nanofiltration permeating acid liquid enters a first stage nanofiltration filtrate tank 7, and then passes through a second stage nanofiltration delivery pump 8 and a second stage nanofiltration membrane device 9 to obtain a more pure second stage nanofiltration permeating acid liquid (Fe)2+Concentration < 200ppm) and second nanofiltration concentrate; returning the secondary nanofiltration concentrated solution to a pretreatment filtrate collection tank, allowing the secondary nanofiltration permeated acid solution to enter a secondary nanofiltration filtrate tank 10, then feeding the secondary nanofiltration permeated acid solution into an acid preconcentration device 12 through a preconcentration conveying pump 11, and preliminarily concentrating the dilute sulfuric acid to a concentration of 13-30% to obtain preconcentrated acid solution, wherein the obtained distilled water or fresh water can be directly returned for production and utilization;
(5) the pre-concentrated acid liquor enters a pre-concentrated acid liquor tank 13 and is sent to an evaporation concentration device 15 through an evaporation feeding transfer pump 14 for final concentration, concentrated sulfuric acid (C is more than or equal to 65%) required by recycling is finally obtained, and similarly, the distilled water obtained in addition is directly returned to production and utilization.
FIG. 2 is a simplified flow chart of the pretreatment filtering device:
the filter aid slurry is pumped to a pretreatment filter 24 through a pretreatment feed pump 23 for circulating filtration and backflow, the filter aid in a filter aid slurry tank 21 is pre-coated on the surface of a filter element (filter bag) in the pretreatment filter to form a filter cake layer with a certain thickness, then a washing dilute acid solution in a stock solution collecting tank 22 is switched to feed, and pure filtrate meeting the water inlet quality requirement of a subsequent nanofiltration system can be obtained through the pretreatment filter and can enter a pretreatment filtrate tank 25;
when the water production efficiency of the pretreatment filter is reduced, the water inlet pressure reaches an upper limit set value and a certain filter cake layer is formed, the water production and filtration are stopped, a compressed air inlet valve is switched, air in a compressed air storage tank 26 is blown forward to dry a filter cake, and then the dry titanium pigment residue is discharged in a reverse blowing mode;
and cutting off a compressed air inlet valve, opening a tap water inlet valve to back flush the filter cloth, and entering the next cycle after the filter cloth is back flushed.
Figure 3 brief description of the two-stage nanofiltration system:
the pretreated filtrate enters a primary nanofiltration system, and is subjected to a primary nanofiltration delivery pump 5, a security filter 19, a high-pressure pump 20 and segmented pressurization and segmented circulation (comprising a primary one-stage one-section membrane unit 21, a primary one-stage one-section circulating reflux pump 22, a primary two-section booster pump 23, a primary two-section membrane unit 24, a primary one-stage two-section circulating reflux pump 25, a primary two-section booster pump 26, a primary three-section membrane unit 27 and a primary three-section circulating reflux pump 28) to respectively obtain a primary nanofiltration salt concentrated solution and a primary nanofiltration permeating acid solution;
the primary nanofiltration permeating acid liquor passes through a secondary nanofiltration conveying pump 8, a security filter 29 and a high-pressure pump 30 to respectively obtain secondary nanofiltration concentrated liquor and secondary nanofiltration permeating acid liquor. Wherein the secondary nanofiltration concentrated solution returns to the pretreatment filtrate collector 4, and the secondary nanofiltration permeates acid liquor to enter a subsequent acid concentration system.
Claims (7)
1. The utility model provides a dilute spent acid membrane integration resourceful treatment system is washed to sulfuric acid process titanium white powder, characterized by: the device comprises a pretreatment filtering device for performing solid-liquid separation on titanium dioxide-washing waste dilute acid, wherein a heat exchanger for exchanging heat and cooling first filtrate obtained by the pretreatment filtering device is arranged behind the pretreatment filtering device, a multi-stage nanofiltration membrane system for performing nanofiltration on the cooled filtrate is arranged behind the heat exchanger, a pre-concentration system for performing pre-concentration on final nanofiltration purified dilute acid solution obtained after nanofiltration by the multi-stage nanofiltration membrane system is arranged behind the multi-stage nanofiltration membrane system, and an evaporation concentration device for performing evaporation concentration on pre-concentrated sulfuric acid solution obtained by the pre-concentration system is arranged in the pre-concentration system.
2. The sulfuric acid process titanium dioxide one-washing dilute waste acid film integrated resource treatment system according to claim 1, which is characterized in that: the pretreatment filtering device comprises a filter element in a tank body, and two sides of the filter element are connected with a circulating filtering backflow pipeline; the tank body is provided with air blowing ports which are respectively positioned at two sides of the filter element.
3. The sulfuric acid process titanium dioxide one-washing dilute waste acid film integrated resource treatment system according to claim 1 or 2, which is characterized in that: the heat exchanger is a plate-exchange type heat exchange device, and the acid liquor overflowing part is made of strong acid resistant materials.
4. The sulfuric acid process titanium dioxide one-washing dilute waste acid film integrated resource treatment system according to claim 1 or 2, which is characterized in that: the multi-stage nanofiltration membrane system has two or more stages, namely, the first-stage nanofiltration purified liquid is taken as second-stage nanofiltration inlet water to obtain second-stage nanofiltration purified liquid, and the second-stage nanofiltration concentrated liquid is returned and mixed into the first-stage nanofiltration stock solution, and the rest is done in the same way; the number of stages of each stage of nanofiltration system in the multistage nanofiltration membrane system is three or more, namely, the first stage of nanofiltration water enters the first stage of membrane unit to produce concentrated water as first-stage concentrated water, the first-stage concentrated water enters the second stage of membrane unit to produce concentrated water as second-stage concentrated water, and the second-stage concentrated water enters the third stage of membrane unit to produce concentrated water as third-stage concentrated water.
5. The sulfuric acid process titanium dioxide once-washing dilute waste acid film integrated resource treatment system according to claim 4, which is characterized in that: the primary nanofiltration system in the multistage nanofiltration membrane system adopts a primary three-section form and adopts sectional pressurization and sectional circulating reflux.
6. The sulfuric acid process titanium dioxide one-washing dilute waste acid film integrated resource treatment system according to claim 1 or 2, which is characterized in that: the pre-concentration system is a multi-stage flash evaporation, membrane distillation or electrodialysis system.
7. The sulfuric acid process titanium dioxide one-washing dilute waste acid film integrated resource treatment system according to claim 1 or 2, which is characterized in that: the effect number of the evaporation concentration device is in a single-effect, double-effect, triple-effect or double-effect and single-effect combination form.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114057167A (en) * | 2021-12-15 | 2022-02-18 | 南通三圣石墨设备科技股份有限公司 | Sulfuric acid method titanium dioxide one-washing diluted waste acid film integrated recycling zero-discharge treatment method |
| CN116282626A (en) * | 2022-12-29 | 2023-06-23 | 山东天维膜技术有限公司 | Method for improving utilization rate of sulfuric acid in acidic wastewater in titanium dioxide industry |
| CN119977213A (en) * | 2025-02-23 | 2025-05-13 | 科纳诺流体科技(杭州)有限公司 | Full membrane treatment process and device for purifying and concentrating acid in acidic wastewater |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114057167A (en) * | 2021-12-15 | 2022-02-18 | 南通三圣石墨设备科技股份有限公司 | Sulfuric acid method titanium dioxide one-washing diluted waste acid film integrated recycling zero-discharge treatment method |
| CN116282626A (en) * | 2022-12-29 | 2023-06-23 | 山东天维膜技术有限公司 | Method for improving utilization rate of sulfuric acid in acidic wastewater in titanium dioxide industry |
| CN119977213A (en) * | 2025-02-23 | 2025-05-13 | 科纳诺流体科技(杭州)有限公司 | Full membrane treatment process and device for purifying and concentrating acid in acidic wastewater |
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