An apparatus and method for utilizing polishing wastewater from electrochromic glass substrates.

Abstract

This invention relates to a device and method for utilizing polishing wastewater from electrochromic glass substrates, relating to the field of water treatment. The device includes a circulating separation unit comprising a cavity containing an i-stage baffle filter plate (i ≥ 11). The i-stage baffle filter plates are distributed from top to bottom, and the diameter of the filter holes on the n-th stage baffle filter plate is greater than the diameter of the filter holes on the (n+1)-th stage baffle filter plate, where n < i. The bottom of the cavity includes a circulating water accumulation zone and a suspended solids accumulation zone surrounding the circulating water accumulation zone. The suspended solids accumulation zone is sequentially connected to a distillation unit, a sedimentation unit, a neutralization unit, and a solid-liquid separation unit. The device provided by this invention, through segmented processing and gradual return of related water treatment equipment, achieves efficient treatment of polishing wastewater, enabling the reuse of most of the wastewater and effective recovery of valuable components, thus realizing the secondary utilization of wastewater resources.

Description

Technical Field

[0001] This invention relates to the field of water treatment, and more specifically to an apparatus and method for utilizing polishing wastewater from electrochromic glass substrates. Background Technology

[0002] The main structure of all-solid-state electrochromic glass consists of a glass substrate, an ion blocking layer, a first conductive layer, a composite functional layer, and a second conductive layer. Its electrical model can be basically equivalent to the charging and discharging behavior of a capacitor-resistor series model.

[0003] Currently, the production of all-solid-state electrochromic glass usually requires grinding the sides of the glass, specifically before and after the relevant film deposition.

[0004] For example, CN119591315A discloses a processing method for electrochromic glass and an electrochromic glass substrate, which includes: S1, pre-treating a tempered glass substrate; S2, subjecting the pre-treated tempered glass substrate to pressurized air cooling treatment, wherein the air pressure during the pressurized air cooling treatment is 12000-16000Pa, until the stress of the tempered glass substrate reaches a first expected stress value, thereby obtaining a pre-tempered tempered glass substrate; S3, performing electrochromic processing on the surface of the pre-tempered tempered glass substrate, wherein the electrochromic processing includes annealing treatment at a temperature of 300-400℃, so that the stress of the pre-tempered tempered glass substrate reaches a second expected stress value.

[0005] During the polishing process, water is usually used as a lubricant or coolant. This results in the water containing a certain amount of glass powder and film material, making it impossible to directly reuse the water in other processes. Directly treating the polishing wastewater is not economically viable because the amount of glass powder and film material produced in a single polishing session is relatively small. On the other hand, storing the wastewater would lead to a large amount of wastewater, which is not conducive to the rational use of water resources. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a device and method for utilizing polishing wastewater from electrochromic glass substrates, so as to achieve secondary and efficient utilization of polishing wastewater, and at the same time recover valuable products in the wastewater.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a device for utilizing polishing wastewater from electrochromic glass substrates, the device comprising:

[0009] Circulation separation equipment, distillation equipment, sedimentation equipment, neutralization equipment, solid-liquid separation equipment, silicon recovery equipment, and indium-tin extraction and recovery equipment;

[0010] The circulating separation device includes: a cavity, wherein an i-stage baffle separation filter plate is disposed in the cavity, i≥11; the i-stage baffle separation filter plates are distributed from top to bottom, and the diameter of the filter holes on the n-th stage baffle separation filter plate is greater than the diameter of the filter holes on the (n+1)-th stage baffle separation filter plate, n<i, and the length of the n-th stage baffle separation filter plate is greater than the length of the (n+1)-th stage baffle separation filter plate;

[0011] The top of the circulating separation device is provided with a grinding wastewater inlet; the bottom of the cavity includes: a circulating water accumulation zone and a suspended solids accumulation zone surrounding the circulating water accumulation zone; the diameter of the circulating water accumulation zone is less than the diameter of the i-th stage baffle filter plate;

[0012] The suspended solids water accumulation zone is sequentially connected to the distillation equipment, sedimentation equipment, neutralization equipment, and solid-liquid separation equipment; the solid phase outlet of the solid-liquid separation equipment is connected to the silicon recovery equipment.

[0013] The liquid phase outlet of the solid-liquid separation equipment is connected to the indium-tin extraction and recovery equipment.

[0014] The grinding wastewater utilization device of this invention, through segmented treatment and gradual return of related water treatment equipment, achieves efficient treatment of grinding wastewater, enabling the reuse of most of the wastewater, and effectively recovering valuable components in the grinding wastewater, thus realizing the secondary utilization of wastewater resources.

[0015] As a preferred technical solution of the present invention, the water in the circulating water accumulation zone is returned to the polishing process of the electrochromic glass substrate.

[0016] Preferably, the liquid phase in the suspended solids water accumulation zone is returned to the baffle separation filter plate through pipelines and pumps.

[0017] As a preferred embodiment of the present invention, the concentrate outlet of the distillation equipment is connected to the sedimentation equipment.

[0018] Preferably, the condensate outlet of the distillation equipment is connected to the return water system.

[0019] As a preferred embodiment of the present invention, the slurry outlet of the sedimentation device is connected to the neutralization device.

[0020] Preferably, the supernatant outlet of the sedimentation device is connected to the return water system.

[0021] As a preferred embodiment of the present invention, the included angle α between the baffle separation filter plate and the side of the cavity is 45-60°.

[0022] Preferably, the diameter of the filter pores in the i-stage baffle separation filter plate is 0.025-1 mm.

[0023] Secondly, the present invention provides a method for utilizing polishing wastewater from electrochromic glass substrates, the method comprising:

[0024] The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water.

[0025] The resulting suspension of water was distilled to obtain a concentrated solution and condensate.

[0026] The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant;

[0027] The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase;

[0028] The solid phase is subjected to silicon recovery to obtain sodium silicate;

[0029] The liquid phase is extracted and recovered to obtain tin-indium recovery products.

[0030] As a preferred embodiment of the present invention, the distillation endpoint is a concentrate concentration of 8-12%.

[0031] As a preferred embodiment of the present invention, the sedimentation endpoint is a slurry mass concentration of 15-25%.

[0032] As a preferred embodiment of the present invention, the endpoint of the neutralization treatment is that the pH value of the neutralized material is 6-7.

[0033] Preferably, the solid-liquid separation method includes one or a combination of at least two of sedimentation, centrifugation, or filtration.

[0034] As a preferred technical solution of the present invention, the silicon recovery includes: reacting a solid phase with an alkaline solution, followed by drying to obtain a silicate product.

[0035] Preferably, the extraction and recovery includes: extracting the liquid phase with an extractant, then back-extracting to obtain an aqueous phase, and then performing a displacement reaction on the obtained aqueous phase to obtain the indium tin product.

[0036] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0037] The grinding wastewater utilization device provided by the present invention achieves efficient recycling of grinding wastewater through a tiered separation and tiered recovery process, with a water reuse rate of ≥90.2%, a silicon recovery rate of ≥99.8%, and an indium-tin recovery rate of ≥99.5%. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of a device for utilizing polishing wastewater from electrochromic glass substrates provided in an embodiment of the present invention.

[0039] In the diagram: 100 - Circulation separation equipment, 110 - Baffled separation filter plate, 120 - Suspended solids water accumulation zone, 130 - Circulating water accumulation zone, 140 - Grinding wastewater inlet, 200 - Distillation equipment, 300 - Sedimentation equipment, 400 - Neutralization equipment, 500 - Solid-liquid separation equipment, 600 - Silicon recovery equipment, 700 - Indium tin extraction and recovery equipment.

[0040] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0041] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0042] Currently, the production of all-solid-state electrochromic glass typically requires side grinding of the glass, specifically before and after the deposition of related film layers. During the grinding process, water is usually used as a lubricant or coolant, resulting in the formation of water containing a certain amount of glass powder and film layer material. This makes the water unsuitable for direct reuse in other processes. Direct treatment of grinding wastewater is inefficient due to the small amount of glass powder and film layer material produced per grinding cycle, making it uneconomical. Furthermore, continuous storage leads to large amounts of wastewater, hindering the rational utilization of water resources. Therefore, this invention optimizes the treatment process of grinding wastewater, enabling effective water reuse and efficient recovery of valuable components, thereby achieving the resource utilization of grinding wastewater. The details are as follows:

[0043] I. This embodiment provides a device for utilizing polishing wastewater from electrochromic glass substrates, such as... Figure 1 As shown, the grinding wastewater utilization device includes:

[0044] The equipment includes: a circulating separation unit 100, a distillation unit 200, a sedimentation unit 300, a neutralization unit 400, a solid-liquid separation unit 500, a silicon recovery unit 600, and an indium-tin extraction and recovery unit 700.

[0045] The circulating separation device 100 includes: a cavity, wherein an i-stage baffle separation filter plate 110 is disposed in the cavity, i ≥ 11; the i-stage baffle separation filter plates 110 are distributed from top to bottom, and the diameter of the filter holes on the n-th stage baffle separation filter plate 110 is greater than the diameter of the filter holes on the (n+1)-th stage baffle separation filter plate 110, n < i, and the length of the n-th stage baffle separation filter plate 110 is greater than the length of the (n+1)-th stage baffle separation filter plate 110;

[0046] The top of the circulating separation device 100 is provided with a grinding wastewater inlet 140; the bottom of the cavity includes: a circulating water accumulation zone 130 and a suspended solids accumulation zone 120 arranged around the circulating water accumulation zone 130; the diameter of the circulating water accumulation zone 130 is less than the diameter of the i-th stage baffle separation filter plate 110;

[0047] The suspended solids water accumulation zone 120 is sequentially connected to the distillation equipment 200, the sedimentation equipment 300, the neutralization equipment 400, and the solid-liquid separation equipment 500; the solid phase outlet of the solid-liquid separation equipment 500 is connected to the silicon recovery equipment 600.

[0048] The liquid phase outlet of the solid-liquid separation device 500 is connected to the indium-tin extraction and recovery device 700.

[0049] In this invention, the i-th stage baffle separation filter plate 110 refers to a continuously zigzag-distributed separation filter plate. Along the liquid flow direction, the distance between the end of the n-th stage and the side is less than the distance between the beginning of the n+1-th stage and the side. That is, the length of the i-th stage baffle separation filter plate 110 gradually decreases from top to bottom. However, it is necessary to ensure that the diameter of the circulating water accumulation zone 130 is less than the diameter of the i-th stage baffle separation filter plate 110, so as to ensure that the liquid phase on the filter plate does not enter the circulating water accumulation zone 130, thereby ensuring that the water phase in the circulating water accumulation zone 130 can be returned to the grinding process for use.

[0050] In this invention, the sidewall of the circulating separation device 100 is partially connected to the baffle separation filter plate 110 to ensure that large particles on the baffle separation filter plate 110 are washed to the sidewall by the water flow and then guided to the suspended solids water accumulation zone 120.

[0051] The water in the circulating water accumulation zone 130 is returned to the polishing process of the electrochromic glass substrate.

[0052] The liquid phase in the suspended solids water accumulation zone 120 is returned to the baffle separation filter plate 110 through pipelines and pumps.

[0053] The concentrated liquid outlet of the distillation device 200 is connected to the sedimentation device 300.

[0054] In this invention, the distillation apparatus 200 is a commonly used distillation apparatus in the art. The distillation method can be selected as atmospheric pressure, pressurized, or depressurized. The distillation apparatus 200 specifically includes an evaporator and a condenser, as well as other control systems, which can be designed and selected according to the conventional requirements in the art.

[0055] The condensate outlet of the distillation equipment 200 is connected to the return water system.

[0056] In this invention, the water return system refers to a system that transports water that meets the reuse standards. Specifically, the water output from the water return system can be fed into the grinding process, the liquid preparation system, or other end-users that can use the returned water, according to actual needs.

[0057] The slurry outlet of the sedimentation device 300 is connected to the neutralization device 400.

[0058] In this invention, the sedimentation equipment 300 can be selected as a sedimentation tank, thickener, sedimentation vessel, etc.

[0059] In this invention, the neutralization device 400 refers to the device that adjusts the pH value of the material to achieve neutralization, that is, the pH value is about 6-7.

[0060] In this invention, sedimentation and distillation can be carried out in one device, such as distillation and sedimentation at room temperature.

[0061] The supernatant outlet of the sedimentation device 300 is connected to the return water system.

[0062] The included angle α between the baffle separation filter plate 110 and the side of the cavity is 45-60°, for example, it can be 45°, 46.5°, 48°, 49.5°, 51°, 52.5°, 54°, 55.5°, 57°, 58.5° or 60°, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0063] The diameter of the filter holes in the i-stage baffle separation filter plate 110 is 0.025-1mm.

[0064] In this invention, the diameter of the filter holes in the i-th stage baffle separation filter plate 110 is 0.025-1mm. This refers to the diameter requirement of the filter holes in each stage of the baffle separation filter plate 110. The specific design can be reasonably selected according to the actual requirements. For example, if the baffle separation filter plate 110 has 11 stages, the diameter of the filter holes in each stage of the baffle separation filter plate 110 is distributed as follows: from stage 1 to stage 11, 1mm, 0.8mm, 0.6mm, 0.4mm, 0.2mm, 0.1mm, 0.08mm, 0.06mm, 0.05mm, 0.04mm and 0.025mm.

[0065] In this invention, the treatment process of the grinding wastewater by the circulating separation device 100 is as follows:

[0066] Grinding wastewater is fed in through grinding wastewater inlet 140. At this time, the grinding wastewater is separated by flowing along the surface of the baffle separation filter plate 110 and dripping directly downwards through the filter holes on the baffle separation filter plate 110. The liquid phase flowing out from the surface of the final baffle separation filter plate 110 enters the suspended solids water accumulation zone 120, and the liquid phase on the final baffle separation filter plate 110 that has passed through the filter holes enters the circulating water accumulation zone 130 and is fed into the grinding process for reuse.

[0067] II. This embodiment provides a method for utilizing polishing wastewater from electrochromic glass substrates, the method comprising:

[0068] The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water.

[0069] The resulting suspension of water was distilled to obtain a concentrated solution and condensate.

[0070] The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant;

[0071] The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase;

[0072] The solid phase is subjected to silicon recovery to obtain sodium silicate;

[0073] The liquid phase is extracted and recovered to obtain tin-indium recovery products.

[0074] The endpoint of the distillation is a concentrated solution with a mass concentration of 8-12%, such as 8%, 8.4%, 8.8%, 9.2%, 9.6%, 10%, 10.4%, 10.8%, 11.2%, 11.6%, or 12%, but not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0075] The endpoint of the sedimentation is a slurry concentration of 15-25%, for example, it can be 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24% or 25%, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0076] The endpoint of the neutralization process is a pH value of 6-7 for the neutralized material. For example, it can be 6, 6.2, 6.4, 6.6, 6.8, or 7, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0077] The solid-liquid separation method includes one or a combination of at least two of sedimentation, centrifugation, or filtration.

[0078] The silicon recovery process includes reacting a solid phase with an alkaline solution, followed by drying to obtain a silicate product.

[0079] In this invention, the alkaline solution used in silicon recovery can be rationally selected according to the intended use of the obtained silicate. For example, when the obtained silicate is used for glass preparation, sodium hydroxide solution can be used for dissolution reaction, followed by drying to obtain sodium silicate product. The amount and concentration of alkaline solution can be rationally designed according to the silicon content of the solid phase and the requirements of the silicate product.

[0080] The extraction and recovery process includes: extracting the liquid phase with an extractant, then back-extracting to obtain the aqueous phase, and then subjecting the obtained aqueous phase to a displacement reaction to obtain the indium tin product.

[0081] In this invention, the indium-tin product is obtained by extraction from the liquid phase. Conventional extractants in the art can be used for extraction. Specifically, indium-enriched phase and tin-enriched phase can be obtained by extraction separately, or indium and tin can be co-extracted to obtain a co-extracted enriched phase of indium and tin. The specific selection and design can be made according to the final actual needs. This invention does not make specific requirements. For specific design, please refer to the prior art CN120519714A, CN101463425A, CN120006099A, etc.

[0082] III. To illustrate the efficient wastewater utilization effect achieved by the wastewater utilization device for polishing electrochromic glass substrates provided by the present invention, the following example is used for explanation:

[0083] Example 1

[0084] This embodiment provides a device for utilizing polishing wastewater from electrochromic glass substrates. The device includes:

[0085] Circulation separation equipment, distillation equipment, sedimentation equipment, neutralization equipment, solid-liquid separation equipment, silicon recovery equipment, and indium-tin extraction and recovery equipment;

[0086] The circulating separation device includes: a cavity, wherein i-stage baffle separation filter plates are arranged in the cavity, i=11; the i-stage baffle separation filter plates are distributed from top to bottom, and the diameter of the filter holes on the n-th stage baffle separation filter plate is greater than the diameter of the filter holes on the (n+1)-th stage baffle separation filter plate, n<i, and the length of the n-th stage baffle separation filter plate is greater than the length of the (n+1)-th stage baffle separation filter plate; the included angle α between the baffle separation filter plate and the side of the cavity is 60°; the diameter of the filter holes in the i-stage baffle separation filter plate is 0.025-1mm, from stage 1 to stage 11, 1mm, 0.8mm, 0.6mm, 0.4mm, 0.2mm, 0.1mm, 0.08mm, 0.06mm, 0.05mm, 0.04mm and 0.025mm;

[0087] The top of the circulating separation device is provided with a grinding wastewater inlet; the bottom of the cavity includes: a circulating water accumulation zone and a suspended solids accumulation zone surrounding the circulating water accumulation zone; the diameter of the circulating water accumulation zone is less than the diameter of the i-th stage baffle filter plate;

[0088] The suspended solids water accumulation zone is sequentially connected to the distillation equipment, sedimentation equipment, neutralization equipment, and solid-liquid separation equipment; the solid phase outlet of the solid-liquid separation equipment is connected to the silicon recovery equipment.

[0089] The liquid phase outlet of the solid-liquid separation equipment is connected to the indium tin extraction and recovery equipment;

[0090] The water in the circulating water accumulation area is returned to the polishing process of the electrochromic glass substrate.

[0091] The liquid phase in the suspended solids water accumulation zone is returned to the baffle filter plate through pipelines and pumps;

[0092] The concentrated liquid outlet of the distillation equipment is connected to the sedimentation equipment;

[0093] The condensate outlet of the distillation equipment is connected to the water return system.

[0094] The slurry outlet of the sedimentation equipment is connected to the neutralization equipment;

[0095] The supernatant outlet of the sedimentation equipment is connected to the return water system.

[0096] Application Example 1

[0097] This application example provides a method for utilizing polishing wastewater from electrochromic glass substrates. Specifically, it is implemented using the wastewater utilization device for electrochromic glass substrates described in Example 1, as detailed below:

[0098] The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water.

[0099] The resulting suspension of water was distilled to obtain a concentrated solution and condensate.

[0100] The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant;

[0101] The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase;

[0102] The solid phase is subjected to silicon recovery to obtain sodium silicate;

[0103] The liquid phase is subjected to extraction and recovery to obtain tin-indium recovery products;

[0104] The distillation endpoint is when the concentrate has a mass concentration of 10%.

[0105] The sedimentation endpoint is when the mass concentration of the slurry reaches 20%.

[0106] The endpoint of the neutralization process is that the pH value of the neutralized material is 6.5;

[0107] The solid-liquid separation method is centrifugation;

[0108] The silicon recovery process includes reacting a solid phase with an alkaline solution (1 mol / L sodium hydroxide), followed by drying to obtain a silicate product.

[0109] The extraction and recovery process includes: extracting the liquid phase with an extractant (P204), then back-extracting to obtain an aqueous phase, and then subjecting the obtained aqueous phase to a displacement reaction to obtain the indium tin product.

[0110] Application Example 2

[0111] This application example provides a method for utilizing polishing wastewater from electrochromic glass substrates. Specifically, it is implemented using the wastewater utilization device for electrochromic glass substrates described in Example 1, as detailed below:

[0112] The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water.

[0113] The resulting suspension of water was distilled to obtain a concentrated solution and condensate.

[0114] The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant;

[0115] The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase;

[0116] The solid phase is subjected to silicon recovery to obtain sodium silicate;

[0117] The liquid phase is subjected to extraction and recovery to obtain tin-indium recovery products;

[0118] The distillation endpoint is when the concentrate has a mass concentration of 8%.

[0119] The sedimentation endpoint is when the mass concentration of the slurry reaches 15%.

[0120] The endpoint of the neutralization process is a pH value of 6 for the neutralized material.

[0121] The solid-liquid separation method is centrifugation;

[0122] The silicon recovery process includes reacting a solid phase with an alkaline solution (1 mol / L sodium hydroxide), followed by drying to obtain a silicate product.

[0123] The extraction and recovery process includes: extracting the liquid phase with an extractant (P204), then back-extracting to obtain an aqueous phase, and then subjecting the obtained aqueous phase to a displacement reaction to obtain the indium tin product.

[0124] Application Example 3

[0125] This application example provides a method for utilizing polishing wastewater from electrochromic glass substrates. Specifically, it is implemented using the wastewater utilization device for electrochromic glass substrates described in Example 1, as detailed below:

[0126] The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water.

[0127] The resulting suspension of water was distilled to obtain a concentrated solution and condensate.

[0128] The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant;

[0129] The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase;

[0130] The solid phase is subjected to silicon recovery to obtain sodium silicate;

[0131] The liquid phase is subjected to extraction and recovery to obtain tin-indium recovery products;

[0132] The distillation endpoint is when the concentrate has a mass concentration of 12%.

[0133] The sedimentation endpoint is when the mass concentration of the slurry reaches 25%.

[0134] The endpoint of the neutralization process is a pH value of 7 for the neutralized material.

[0135] The solid-liquid separation method is filtration;

[0136] The silicon recovery process includes reacting a solid phase with an alkaline solution (1 mol / L sodium hydroxide), followed by drying to obtain a silicate product.

[0137] The extraction and recovery process includes: extracting the liquid phase with an extractant (P204), then back-extracting to obtain an aqueous phase, and then subjecting the obtained aqueous phase to a displacement reaction to obtain the indium tin product.

[0138] The utilization effect of grinding wastewater and the recovery effect of silicon, indium and tin in the above application examples are detailed in Table 1 below. Among them, the water reuse rate refers to the mass ratio of the circulating water generated in the circulating water accumulation zone to the grinding wastewater; the silicon recovery rate refers to the ratio of the silicon content in the silicate product to the silicon content in the grinding wastewater; the indium-tin recovery rate refers to the ratio of the total indium and tin content in the indium-tin product to the total indium and tin content in the grinding wastewater.

[0139] Table 1

[0140]

[0141] As shown in Table 1, the grinding wastewater utilization device of the present invention, through segmented treatment and gradual return of related water treatment equipment, achieves efficient treatment of grinding wastewater, can reuse most of the wastewater, and can effectively recover valuable components in the grinding wastewater, thus realizing the secondary utilization of wastewater resources.

[0142] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0143] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0144] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A device for utilizing polishing wastewater from electrochromic glass substrates, characterized in that, The grinding wastewater utilization device includes: Circulation separation equipment, distillation equipment, sedimentation equipment, neutralization equipment, solid-liquid separation equipment, silicon recovery equipment, and indium-tin extraction and recovery equipment; The circulating separation device includes: a cavity, wherein an i-stage baffle separation filter plate is disposed in the cavity, i≥11; the i-stage baffle separation filter plates are distributed from top to bottom, and the diameter of the filter holes on the n-th stage baffle separation filter plate is greater than the diameter of the filter holes on the (n+1)-th stage baffle separation filter plate, n<i, and the length of the n-th stage baffle separation filter plate is greater than the length of the (n+1)-th stage baffle separation filter plate; The top of the circulating separation device is provided with a grinding wastewater inlet; the bottom of the cavity includes: a circulating water accumulation zone and a suspended solids accumulation zone surrounding the circulating water accumulation zone; the diameter of the circulating water accumulation zone is less than the diameter of the i-th stage baffle filter plate; The suspended solids water accumulation zone is sequentially connected to the distillation equipment, sedimentation equipment, neutralization equipment, and solid-liquid separation equipment; the solid phase outlet of the solid-liquid separation equipment is connected to the silicon recovery equipment. The liquid phase outlet of the solid-liquid separation equipment is connected to the indium-tin extraction and recovery equipment.

2. The grinding wastewater utilization device as described in claim 1, characterized in that, The water in the circulating water accumulation area is returned to the polishing process of the electrochromic glass substrate. Preferably, the liquid phase in the suspended solids water accumulation zone is returned to the baffle separation filter plate through pipelines and pumps.

3. The grinding wastewater utilization device as described in claim 1, characterized in that, The concentrated liquid outlet of the distillation equipment is connected to the sedimentation equipment; Preferably, the condensate outlet of the distillation equipment is connected to the return water system.

4. The grinding wastewater utilization device as described in claim 1, characterized in that, The slurry outlet of the sedimentation equipment is connected to the neutralization equipment; Preferably, the supernatant outlet of the sedimentation device is connected to the return water system.

5. The grinding wastewater utilization device as described in claim 1, characterized in that, The included angle α between the baffle separation filter plate and the side of the cavity is 45-60°; Preferably, the diameter of the filter pores in the i-stage baffle separation filter plate is 0.025-1 mm.

6. A method for utilizing polishing wastewater from electrochromic glass substrates, characterized in that, The method for utilizing grinding wastewater includes: The polishing wastewater from the electrochromic glass substrate was treated using a circulating separation device to obtain suspended solids water. The resulting suspension of water was distilled to obtain a concentrated solution and condensate. The concentrate is subjected to sedimentation to obtain a concentrated slurry and a supernatant; The concentrated slurry is subjected to neutralization and solid-liquid separation in sequence to obtain a solid phase and a liquid phase; The solid phase is subjected to silicon recovery to obtain sodium silicate; The liquid phase is extracted and recovered to obtain tin-indium recovery products.

7. The method for utilizing grinding wastewater as described in claim 6, characterized in that, The distillation process ends when the concentration of the concentrate is 8-12%.

8. The method for utilizing grinding wastewater as described in claim 6, characterized in that, The sedimentation endpoint is when the mass concentration of the slurry is 15-25%.

9. The method for utilizing grinding wastewater as described in claim 6, characterized in that, The endpoint of the neutralization process is a pH value of 6-7 for the neutralized material. Preferably, the solid-liquid separation method includes one or a combination of at least two of sedimentation, centrifugation, or filtration.

10. The method for utilizing grinding wastewater as described in claim 6, characterized in that, The silicon recovery process includes reacting a solid phase with an alkaline solution, followed by drying to obtain a silicate product. Preferably, the extraction and recovery includes: extracting the liquid phase with an extractant, then back-extracting to obtain an aqueous phase, and then performing a displacement reaction on the obtained aqueous phase to obtain the indium tin product.

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