White carbon black wastewater resource utilization method and device

Abstract

The invention relates to a method for recycling white carbon black wastewater, in particular to a process for extracting sodium sulfate from saline water containing organic matters, silicon dioxide and sodium sulfate and converting the sodium sulfate into acid and alkali to be reused in a production process, which comprises the following steps: introducing a solution containing the organic matters, the silicon dioxide and the sodium sulfate into an inorganic membrane device; introducing the permeate of the inorganic membrane device into a reverse osmosis device to obtain a high-concentration sodium sulfate solution; introducing the reverse osmosis concentrated solution into an evaporative crystallization device to obtain anhydrous sodium sulphate; dissolving anhydrous sodium sulphate, and introducing the dissolved anhydrous sodium sulphate into a bipolar membrane device for electrolysis to obtain a sulfuric acid solution and a sodium hydroxide solution; sodium sulfate can be extracted from organic matters, silicon dioxide and sodium sulfate, and the sodium sulfate is converted into acid and alkali.

Description

TECHNICAL FIELD

[0001] The present application relates to a white carbon black wastewater resource utilization method, belonging to the technical field of silicon-containing / organic-containing concentrated brine resource utilization. BACKGROUND

[0002] White carbon black is a general term for white powder amorphous silicic acid and silicate products, mainly composed of silicon dioxide, and is widely used. Amorphous silicon dioxide is another excellent reinforcing filler after carbon black. Because its color is white, it is called white carbon black.

[0003] At present, the main production methods of white carbon black at home and abroad are gas phase method and precipitation method. The precipitation method mainly uses sulfuric acid precipitation method, which produces two kinds of wastewater during production, one is white carbon black mother liquor, and the other is white carbon black washing water. At the same time, small silicon dioxide particles will enter the wastewater during washing, thereby increasing the suspended solids content of the wastewater and the difficulty of treatment.

[0004] There are usually two methods for treating conventional white carbon black wastewater. One is direct evaporation treatment, which has problems such as large investment and high operating cost. The other is reverse osmosis concentration and then frozen crystallization or evaporation crystallization treatment, which has problems such as reverse osmosis membrane pollution, high operating cost, and blocked salt outlet. Therefore, how to efficiently, economically and environmentally treat these white carbon black wastewater has become a technical problem to be solved in the white carbon black industry.

[0005] At present, researchers are actively exploring various methods, such as resource utilization (such as extracting class I first-grade meta alum powder and electrolyzing to obtain acid and alkali), deep treatment (such as advanced oxidation and membrane separation technology to further purify water quality), and recycling technology (such as recycling water for production process after appropriate treatment), in order to maximize the utilization of resources and minimize the discharge of waste, and promote the green upgrading and sustainable development of the white carbon black industry. SUMMARY

[0006] In view of the above problems, it is urgent to develop a high-efficiency and low-cost technology for resource utilization of salt in white carbon black wastewater, to solve the disposal problem and recover economically valuable inorganic salt, thereby reducing the operating cost of zero emission.

[0007] The application provides a method for treating white carbon black wastewater and recycling the white carbon black wastewater.

[0008] A method for recycling white carbon black wastewater, comprising the following steps: (1) introducing the white carbon black wastewater into a reaction device, adding a silicon removal agent to the white carbon black wastewater, and performing a chemical silicon removal reaction to obtain a reaction liquid; (2) filtering the reaction liquid through a ceramic membrane to obtain a permeate and a retentate, wherein the retentate contains silica gel or colloidal silica solids; (3) concentrating the permeate through a reverse osmosis membrane to increase the concentration of sodium sulfate, and obtaining a reverse osmosis concentrated liquid; (4) evaporating and crystallizing the reverse osmosis concentrated liquid in an evaporative crystallizer to cause sodium sulfate to crystallize and precipitate, and obtaining a crystallization slurry; (5) separating the crystallization slurry through a solid-liquid separation device to obtain sodium sulfate solids and a mother liquor; (6) resolubilizing the sodium sulfate solids in a dissolving tank to obtain a sodium sulfate solution; (7) performing bipolar membrane electrodialysis on the sodium sulfate solution through a bipolar membrane to obtain sodium hydroxide and sulfuric acid.

[0009] Before the step (1), a mild oxidation pretreatment step is further included: adding an oxidizing agent to the white carbon black wastewater to perform an oxidation reaction to weaken the stabilizing effect of organic matter in the wastewater on colloidal silica, and then entering the chemical silicon removal reaction; the oxidizing agent is selected from hydrogen peroxide, ozone, or a combination of hydrogen peroxide and ozone.

[0010] The reaction temperature of the mild oxidation pretreatment is 20-60°C, and the reaction time is 5-60 min; after the mild oxidation pretreatment is completed, residual oxidation is quenched or removed, and then the chemical silicon removal reaction is performed.

[0011] The silicon removal agent is selected from one or more of magnesium sulfate, aluminum sulfate, and iron sulfate, and the addition amount of the silicon removal agent is 0.1-5 wt% based on the white carbon black wastewater; the stirring time of the chemical silicon removal reaction is 1-30 min, and the reaction temperature is 10-60°C.

[0012] The ceramic membrane has an average pore size of 0.002-1 microns or a molecular weight cut-off of 10,000-5,000,000 Da; the ceramic membrane is made of alumina, zirconia, silicon carbide or titania; the mother liquor separated by the solid-liquid separation device is sent to a dryer for drying treatment to obtain solid residues.

[0013] The bipolar membrane electrodialysis uses a two-compartment bipolar membrane electrodialyzer or a three-compartment bipolar membrane electrodialyzer; the membrane material used in the bipolar membrane electrodialysis is selected from one of PVC, PEEK, PES, PET or PVDF.

[0014] A device for recycling white carbon black wastewater, comprising: A reaction device for performing chemical silicon removal reaction on the white carbon black wastewater; A ceramic membrane connected to the reaction device for filtering the reaction liquid obtained in the reaction device; A reverse osmosis membrane connected to the permeation side of the ceramic membrane for high-concentration concentration of the permeation liquid of the ceramic membrane to increase the concentration of sodium sulfate; An evaporation crystallizer connected to the reverse osmosis membrane for crystallizing and precipitating sodium sulfate; A solid-liquid separation device connected to the evaporation crystallizer for separating out the precipitated sodium sulfate; A dissolving tank connected to the solid-liquid separation device for redissolving the sodium sulfate; A bipolar membrane connected to the dissolving tank for performing bipolar membrane electrodialysis on the redissolved sodium sulfate solution to obtain sulfuric acid and sodium hydroxide; An acid tank and a lye tank connected to the bipolar membrane, respectively, for receiving the obtained sulfuric acid and sodium hydroxide; A silicon removal agent feeding device connected to the feed side of the ceramic membrane or the reaction device for adding a silicon removal agent to the feed of the ceramic membrane or the reaction system.

[0015] Further comprising: an oxidizing agent feeding device connected to the feed side of the ceramic membrane or the reaction device for adding an oxidizing agent to the feed of the ceramic membrane or the reaction system.

[0016] Further comprising a dryer connected to the mother liquor outlet of the solid-liquid separation device for drying treatment of the mother liquor; the solid-liquid separation device is a centrifuge.

[0017] The ceramic membrane is a single-tube, flat-plate or multi-channel ceramic membrane; the ceramic membrane has an average pore size of 0.002-1 microns or a molecular weight cut-off of 10,000-5,000,000 Da; the ceramic membrane is made of alumina, zirconia, silicon carbide or titania.

[0018] The bipolar membrane is a three-compartment bipolar membrane electrodialyzer or a two-compartment bipolar membrane electrodialyzer; the diaphragm material in the bipolar membrane (7) is selected from one of PVC, PEEK, PES, PET or PVDF.

[0019] The beneficial effects of the present application are: the present application provides a white carbon black wastewater resource utilization method and device, which removes silica gel / colloidal silica through chemical silicon removal and ceramic membrane filtration, then concentrates by reverse osmosis, evaporates and crystallizes to separate sodium sulfate and redissolve, finally converts sodium sulfate into sulfuric acid and sodium hydroxide by bipolar membrane electrodialysis, realizes high-value recovery of salt and water reuse. By setting mild oxidation pretreatment, the stability of organic matter to colloidal silica is weakened, the silicon removal effect is enhanced, the risk of membrane pollution is reduced, and the overall resource efficiency and operation economy are improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is the process flow diagram of the present application.

[0022] Figure 2 is the device diagram of the present application.

[0023] 1, reaction device; 2, ceramic membrane; 3, reverse osmosis membrane; 4, evaporation crystallizer; 5, solid-liquid separation equipment; 6, dissolving tank; 7, bipolar membrane; 8, acid tank; 9, lye tank; 10, dryer; 11, silicon removal agent adding device; 12, oxidizing agent adding device. DETAILED DESCRIPTION

[0025] The present application relates to a white carbon black wastewater resource utilization method, which specifically removes solid impurities by inorganic membrane method, realizes preliminary purification of white carbon black wastewater, enters reverse osmosis system for high-concentration, evaporates in the evaporation system, dissolves the obtained sodium sulfate, and then passes through bipolar membrane electrolysis to prepare sodium hydroxide and sulfuric acid, and is returned to the front-end process, finally realizes the white carbon black wastewater resource utilization method. The method can solve the disposal problem, recover economically valuable inorganic salt, reduce zero-emission operation cost, and achieve the purpose of resource utilization.

[0026] Among the white carbon black wastewater that can be treated, the wastewater treated in the following examples is the waste salt water generated in the production process of white carbon black industry.

[0027] White carbon black wastewater, mainly containing sodium sulfate, and containing silicon dioxide and organic matter, the main component Na2SO4 in white carbon black wastewater is 10-50g / L, Mg 2+ 0.001-0.2g / L, Ca 2+0.001-0.2g / L, COD 1-200mg / L, SiO2 0.001-1g / L. The above salt concentration can be determined by ICP method, COD is determined by potassium dichromate method, SiO2 is determined by spectrophotometry.

[0028] The white carbon black wastewater here is first filtered through the ceramic membrane device, which removes silica gel, magnesium hydroxide and suspended solids in the white carbon black wastewater; the ceramic membrane used here has an average pore size of 0.002-1μm or a molecular weight cut-off of 10000-5000000Da, and the operating pressure range is 0.05-0.5Mpa, using cross-flow filtration at a flow rate of 1-10m / s.

[0029] Since the silicon pollution in the white carbon black wastewater is the main cause of the irreversible pollution of the reverse osmosis membrane (silica gel pollution is difficult to remove by flushing), in the present application, by adding a silicon removal agent (such as magnesium sulfate, magnesium oxide, aluminum sulfate, aluminum oxide, iron sulfate, iron oxide, sodium carbonate) to the white carbon black wastewater, and after the reaction of the silicon removal agent, the wastewater is filtered through the ceramic membrane, the silicon pollution of the reverse osmosis membrane can be effectively avoided, and the concentration of the silicon removal agent in the solution can be controlled at 0.1-5%.

[0030] Since the white carbon black wastewater usually contains a certain amount of organic matter (such as dispersant, additive residue, etc.), such organic matter is easy to form an adsorption layer or a composite structure on the surface of colloidal silicon / silicic acid polymer, thereby improving the stability of colloidal silicon and inhibiting its aggregation and growth, causing silicon to enter the subsequent membrane separation unit in the form of smaller and more difficult to remove; in the reverse osmosis concentration process, once the silica gel is enriched on the membrane surface and forms a deposit, it is often difficult to remove by conventional flushing, thereby causing irreversible pollution of the reverse osmosis membrane. The present application adds a mild oxidation pretreatment step before chemical silicon removal, by adding an oxidizing agent (such as hydrogen peroxide, ozone or both) to the white carbon black wastewater to selectively oxidize and destroy the organic stabilizing components, weaken their stabilizing effect on colloidal silicon, and make colloidal silicon more unstable and react with the subsequently added silicon removal agent (such as magnesium sulfate, magnesium oxide, aluminum sulfate, aluminum oxide, iron sulfate, iron oxide, sodium carbonate, etc.) to generate a silica / silicate solid phase that is easy to separate, and then filtered through a ceramic membrane to achieve effective removal, thereby further reducing the risk of silicon pollution of the reverse osmosis membrane and improving the high-concentration stability. The concentration of the silicon removal agent in the solution can be controlled at 0.1-5%, and the amount of the oxidizing agent can be adjusted according to the COD and silicon form of the wastewater to achieve mild oxidation and avoid adverse effects on the subsequent process.

[0031] After ceramic membrane filtration, the permeate of the ceramic membrane is sent to a reverse osmosis membrane concentration treatment, and then to an evaporation crystallization device for treatment to obtain sodium sulfate, which is crystallized by using an MVR evaporator. The sodium sulfate is crystallized by using a micro-negative pressure operation and a continuous crystallizer system, so that the purity and yield of the product are further improved. The temperature control of the evaporation crystallization is 60-90 DEG C, and more preferably 70-80 DEG C. In the actual crystallization process, the crystallization process can be optimized by controlling the evaporation temperature, evaporation rate, stirring intensity and other parameters, so that the crystallization of sodium sulfate is more sufficient and pure.

[0032] After the sodium sulfate is dissolved, sodium hydroxide and sulfuric acid are obtained by bipolar membrane electrolysis. The preferred operating parameters of the bipolar membrane device electrolysis are: the operating voltage is 1-200V, the current is 1-250A, and the feed pressure is 0.02-0.2MPa. The membrane material is selected from one or a combination of PVC, PEEK, PES, PET, PVDF and the like.

[0033] The concentration multiple of the reverse osmosis membrane in the patent refers to the concentration multiple when the flux decreases to 15% of the initial flux.

[0034] The concentrated liquid obtained in the ceramic membrane filtration process is returned to the sedimentation tank for sedimentation treatment, and is used as solid waste for subsequent treatment.

[0035] Based on the above process, the device structure provided by the application is as follows Figure 2 , comprising: A reaction device 1 for performing a chemical silicon removal reaction on white carbon black wastewater; A ceramic membrane 2 connected to the reaction device 1 for filtering the reaction liquid obtained in the reaction device 1; A reverse osmosis membrane 3 connected to the permeation side of the ceramic membrane 2 for high-concentration concentration of the permeate of the ceramic membrane 2 to increase the concentration of sodium sulfate; An evaporation crystallizer 4 connected to the reverse osmosis membrane 3 for crystallizing and precipitating sodium sulfate; A solid-liquid separation device 5 connected to the evaporation crystallizer 4 for separating out the precipitated sodium sulfate; A dissolving tank 6 connected to the solid-liquid separation device 5 for redissolving the sodium sulfate; A bipolar membrane 7 connected to the dissolving tank 6 for bipolar membrane electrodialysis of the redissolved sodium sulfate solution to obtain sulfuric acid and sodium hydroxide; An acid tank 8 and an alkali tank 9 connected to the bipolar membrane 7, respectively, for receiving the obtained sulfuric acid and sodium hydroxide; A silicon removal agent adding device 11 connected to the feed side of the ceramic membrane 2 or the reaction device 1 for adding a silicon removal agent to the ceramic membrane feed or the reaction system.

[0036] An oxidant adding device 12 is connected to the feed side of the ceramic membrane 2 or the reaction device 1, and is used to add an oxidant to the ceramic membrane feed or the reaction system.

[0037] A dryer 10 is further included, which is connected to the mother liquor outlet of the solid-liquid separation device 5, and is used to dry the mother liquor.

[0038] The solid-liquid separation device 5 is a centrifuge.

[0039] The ceramic membrane 2 is a single-tube, flat-plate or multi-channel ceramic membrane.

[0040] The average pore size of the ceramic membrane 2 is 0.002 μm to 1 μm, or the molecular weight cut-off is 10,000 to 5,000,000 Da.

[0041] The material of the ceramic membrane 2 is alumina, zirconia, silicon carbide or titanium oxide.

[0042] The bipolar membrane 7 is a three-compartment bipolar membrane electrodialyzer or a two-compartment bipolar membrane electrodialyzer.

[0043] The diaphragm material in the bipolar membrane 7 is selected from one of PVC, PEEK, PES, PET or PVDF. Example 1

[0044] The white carbon black wastewater containing Na2SO415 g / L, Mg²⁺0.01 g / L, Ca²⁺0.02 g / L, COD 50 mg / L, SiO20.1 g / L is directly fed into a 200 nm ceramic membrane device for filtration, the ceramic membrane operating pressure is 0.3 MPa, and the cross-flow flow rate is 3 m / s, to obtain a ceramic membrane permeate; the ceramic membrane permeate is sent to a reverse osmosis membrane for concentration and then to an evaporation crystallization device, the evaporation temperature is controlled at 75 ℃ to obtain sodium sulfate; the sodium sulfate is dissolved and sent to a bipolar membrane system for electrolysis, the bipolar membrane operating voltage is 100 V, and the operating current density is 600.0 A / m², to generate H2SO4 and NaOH, the acid current efficiency is 77.8%, the base current efficiency is 81.9%, and the mother liquor separated by sodium sulfate evaporation crystallization is sent to a drying treatment as solid waste. Example 2

[0045] The same white carbon black wastewater as in Example 1 and the same ceramic membrane filtration conditions (200 nm ceramic membrane, 0.3 MPa, cross-flow 3 m / s) are used, except that 2 wt% of magnesium sulfate desiliconizing agent is added to the feed liquid before filtration, and no oxidation pretreatment is performed; after the desiliconizing agent reaction treatment, the reverse osmosis concentration factor can be increased from 2 times to 5 times, thereby improving the water recovery rate. Example 3

[0046] The white carbon black wastewater contains Na2SO4 25 g / L, Mg2+ 0.02 g / L, Ca2+ 0.02 g / L, COD 80 mg / L, SiO2 0.15 g / L, and after 1 wt% aluminum sulfate desilication agent is added into the feed liquid entering the ceramic membrane, the ceramic membrane device is filtered at an operating pressure of 0.3 MPa and a cross-flow flow rate of 3 m / s, and solid matters such as silica gel are removed, to obtain a silicon carbide membrane permeate liquid, the ion content of which is Mg2+ 0.001 mg / L, Ca2+ 0.005 mg / L, COD 40 mg / L, Na2SO4 25 g / L, and SiO2 0.005 g / L; the silicon carbide membrane permeate liquid is sent into a reverse osmosis concentration and then into an evaporation crystallization device, and meta alum is obtained by evaporation at a temperature of 80 ℃; the meta alum is dissolved and sent into a bipolar membrane system, an operating voltage of 100 V and an operating current density of 600.0 A / m2 are used, H2SO4 and NaOH are generated, the acid current efficiency is 79.8%, and the base current efficiency is 82.9%. Example 4

[0047] The white carbon black wastewater contains Na2SO4 50 g / L, Mg2+ 0.01 g / L, Ca2+ 0.01 g / L, COD 60 mg / L, SiO2 0.15 g / L, and after 1.5 wt% iron sulfate desilication agent is added into the feed liquid entering the ceramic membrane, the ceramic membrane device is filtered at an operating pressure of 0.3 MPa and a cross-flow flow rate of 3 m / s, and solid matters such as silica gel are removed, to obtain a ceramic membrane permeate liquid, the ion content of which is Mg2+ 0.001 mg / L, Ca2+ 0.003 mg / L, COD 30 mg / L, Na2SO4 50 g / L, and SiO2 0.006 g / L; the ceramic membrane permeate liquid is sent into a reverse osmosis concentration and then into an evaporation crystallization device, and meta alum is obtained by evaporation at a temperature of 78 ℃; the meta alum is dissolved and sent into a bipolar membrane system, an operating voltage of 100 V and an operating current density of 700.0 A / m2 are used, H2SO4 and NaOH are generated, the acid current efficiency is 81.8%, the base current efficiency is 83.9%, and the mother liquor of sodium sulfate evaporation crystallization separation is sent into a drying treatment as solid waste. Example 5

[0048] The same white carbon black wastewater (Na2SO4 15 g / L, Mg2+ 0.01 g / L, Ca2+ 0.02 g / L, COD 50 mg / L, SiO2 0.1 g / L) as in Example 1 was used, and a mild oxidation pretreatment step was added before entering the step 1 dosing reaction treatment and ceramic membrane filtration, that is, hydrogen peroxide was added to the wastewater, the amount of addition was 150 mg / L of effective H2O2, the reaction was carried out at 40 ℃, stirring at 400 rpm for 30 min, after the reaction, a small amount of sodium bisulfite was used to quench the residual oxidant and adjust the pH to 7.0±0.2, the COD of the pretreated wastewater was reduced from about 50 mg / L to about 35 mg / L; then 2 wt% magnesium sulfate was added to the feed liquid entering the ceramic membrane to remove silicon and stirred for 10 min before entering the 200 nm ceramic membrane filtration, the ceramic membrane operating pressure was 0.3 MPa, the cross-flow velocity was 3 m / s, and the ceramic membrane permeate was obtained; the ceramic membrane permeate was sent to the reverse osmosis concentration and then to the evaporation crystallization device, the evaporation temperature was controlled at 75 ℃ to obtain sodium sulfate, and then the sodium sulfate was dissolved and sent to the bipolar membrane system, the operating voltage was 100 V, and the operating current density was 600.0 A / m2; the SiO2 in the ceramic membrane permeate was 0.006 g / L, and the reverse osmosis could be stably concentrated by 5.8 times. Example 6

[0049] The same white carbon black wastewater as in Example 5 was used, and the subsequent process was used, only the pretreatment method was changed to ozone mild oxidation, that is, ozone was introduced into the wastewater in the form of micro-bubbles at 25-30 ℃, the ozone generator outlet concentration was about 40-60 mg / L, the gas-liquid ratio was about 0.5-1.0 Nm3 gas / Nm3 liquid, the aeration time was 20 min, the effective ozone dose converted into liquid phase was about 20 mg / L, after the reaction, the wastewater was allowed to stand for 5 min and a small amount of sodium bisulfite was used to quench the residual oxidant, the COD of the pretreated wastewater was reduced from about 50 mg / L to about 32 mg / L; then 2 wt% magnesium sulfate was added to the feed liquid entering the ceramic membrane to remove silicon and stirred for 10 min before entering the 200 nm ceramic membrane filtration, the ceramic membrane operating pressure was 0.3 MPa, the cross-flow velocity was 3 m / s, and then the reverse osmosis concentration, 75 ℃ evaporation crystallization was used to obtain sodium sulfate which was dissolved and sent to the bipolar membrane system, the working voltage was 100 V, and the current intensity was 600.0 A / m2; the SiO2 in the ceramic membrane permeate was 0.005 g / L. Example 7

[0050] The same white carbon black wastewater and subsequent process as in Example 5 were used, and the pretreatment was changed to mild oxidation with hydrogen peroxide-ozone combination, i.e. first adding hydrogen peroxide, the amount of which was 50 mg / L of effective H2O2, and after stirring for 2 min to make it uniform, ozone was introduced at 25-30 °C in the form of micro-bubbles for 15 min, the effective ozone dose converted into the liquid phase was about 15 mg / L, the total reaction residence time was 20 min, after which a small amount of sodium bisulfite was used to quench the residual oxidation and adjust the pH to 7.0±0.2, the COD after pretreatment was reduced from about 50 mg / L to 28 mg / L; then 2 wt% magnesium sulfate desilication agent was added to the feed liquid entering the ceramic membrane and stirred for 10 min before entering the 200 nm ceramic membrane for filtration, the operating conditions were 0.3 MPa, cross-flow 3 m / s, after which reverse osmosis concentration, 75 °C evaporation crystallization to obtain sodium sulfate and dissolution into the bipolar membrane system, the working voltage was 100 V, the current intensity was 600.0 A / m²; the SiO2 in the ceramic membrane permeate was 0.003-0.004 g / L.

[0051] Results comparison: Example 2 has shown that adding 2 wt% magnesium sulfate desilication agent before entering the ceramic membrane can increase the reverse osmosis concentration ratio from 2 times to 5 times. On this basis, Examples 5-7 only added mild oxidation pretreatment before step 1, and the desilication agent and ceramic membrane filtration conditions remained the same, the test results showed that as the COD after pretreatment decreased, the SiO2 in the ceramic membrane permeate further decreased, from about 0.010 g / L under the same conditions in Example 2 to 0.006, 0.005 and 0.003-0.004 g / L, the reverse osmosis concentration ratio could be further increased stably, from 5.0 times to 5.8, 6.0 and 6.6 times, indicating that the mild oxidation pretreatment weakened the stabilizing effect of organic matter on colloidal silicon, thereby enhancing the destabilization and capture effect of the desilication agent on silica gel / colloidal silicon and reducing the subsequent membrane pollution.

Claims

1. A method for resource utilization of white carbon black wastewater, characterized in that, Comprise the following steps: (1) The white carbon black wastewater is introduced into a reaction device, a silicon removal agent is added to the white carbon black wastewater, and a chemical silicon removal reaction is carried out to obtain a reaction liquid; (2) The reaction liquid is sent to a ceramic membrane for filtration to obtain a permeate and a retentate, and the retentate contains silica gel or colloidal silica solid; (3) The permeate is sent to a reverse osmosis membrane for concentration to increase the concentration of sodium sulfate, and a reverse osmosis concentrated liquid is obtained; (4) The reverse osmosis concentrated liquid is sent to an evaporation crystallizer for evaporation crystallization to crystallize and precipitate sodium sulfate, and a crystallization slurry is obtained; (5) The crystallization slurry is sent to a solid-liquid separation device for separation to obtain sodium sulfate solid and mother liquor; (6) The sodium sulfate solid is sent to a dissolution tank for redissolution to obtain a sodium sulfate solution; (7) The sodium sulfate solution is sent to a bipolar membrane for bipolar membrane electrodialysis to obtain sulfuric acid and sodium hydroxide.

2. The method of claim 1, wherein, Before the step (1), a mild oxidation pretreatment step is further included: an oxidizing agent is added to the white carbon black wastewater for oxidation reaction to weaken the stabilizing effect of organic matter in the wastewater on colloidal silica, and then the white carbon black wastewater enters the chemical silicon removal reaction; the oxidizing agent is selected from hydrogen peroxide, ozone or a combination of hydrogen peroxide and ozone.

3. The method according to claim 2 or 3, characterized in that, The reaction temperature of the mild oxidation pretreatment is 20-60°C, and the reaction time is 5-60 min; after the mild oxidation pretreatment is completed, the residual oxidation is quenched or removed, and then the chemical silicon removal reaction is entered.

4. The method of claim 1, wherein, The silicon removal agent is selected from one or more of magnesium sulfate, aluminum sulfate and iron sulfate, and the addition amount of the silicon removal agent is 0.1-5 wt% based on the white carbon black wastewater; the stirring time of the chemical silicon removal reaction is 1-30 min, and the reaction temperature is 10-60°C.

5. The method of claim 1, wherein, The average pore size of the ceramic membrane is 0.002-1 μm, or the molecular weight cut-off is 10,000-5,000,000 Da; the material of the ceramic membrane is alumina, zirconia, silicon carbide or titanium oxide; the mother liquor separated by the solid-liquid separation device is sent to a dryer for drying treatment to obtain solid residues.

6. The method of claim 1, wherein, The bipolar membrane electrodialysis uses a two-compartment bipolar membrane electrodialyzer or a three-compartment bipolar membrane electrodialyzer; the membrane material used in the bipolar membrane electrodialysis is selected from one of PVC, PEEK, PES, PET or PVDF.

7. A device for resource utilization of white carbon black wastewater, characterized in that, Comprise: a reaction device (1) for chemical silicon removal reaction of white carbon black wastewater; a ceramic membrane (2) connected to the reaction device (1) for filtering the reaction liquid obtained in the reaction device (1); a reverse osmosis membrane (3) connected to the permeate side of the ceramic membrane (2) for high-fold concentration of the permeate of the ceramic membrane (2) to increase the concentration of sodium sulfate; an evaporation crystallizer (4) connected to the reverse osmosis membrane (3) for crystallizing and precipitating sodium sulfate; a solid-liquid separation device (5) connected to the evaporation crystallizer (4) for separating out the precipitated sodium sulfate; a dissolution tank (6) connected to the solid-liquid separation device (5) for redissolving the sodium sulfate; a bipolar membrane (7) connected to the dissolution tank (6) for bipolar membrane electrodialysis of the redissolved sodium sulfate solution to obtain sulfuric acid and sodium hydroxide; An acid liquid tank (8) and an alkali liquid tank (9) are connected to the bipolar membrane (7) respectively for receiving the obtained sulfuric acid and sodium hydroxide; A silicon removal agent adding device (11) is connected to the feed side of the ceramic membrane (2) or the reaction device (1) for adding the silicon removal agent to the ceramic membrane feed or the reaction system.

8. The apparatus of claim 7, wherein, Further comprising: An oxidizing agent adding device (12) is connected to the feed side of the ceramic membrane (2) or the reaction device (1) for adding the oxidizing agent to the ceramic membrane feed or the reaction system; and a dryer (10) is connected to the mother liquor outlet of the solid-liquid separation equipment (5) for drying the mother liquor; The solid-liquid separation equipment (5) is a centrifuge.

9. The apparatus of any of claims 7, wherein, The ceramic membrane (2) is a single-tube, flat-plate or multi-channel ceramic membrane; the average pore size of the ceramic membrane (2) is 0.002-1 μm, or the molecular weight cut-off is 10000-5000000 Da; and the material of the ceramic membrane (2) is alumina, zirconia, silicon carbide or titanium oxide.

10. The apparatus of any of claim 9, wherein, The bipolar membrane (7) is a three-compartment bipolar membrane electrodialyzer or a two-compartment bipolar membrane electrodialyzer; and the diaphragm material of the bipolar membrane (7) is selected from one of PVC, PEEK, PES, PET or PVDF.

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