Metal aqueous solution treatment system and method for treating metal aqueous solution

Abstract

An aqueous metal solution treatment system and a method of treating an aqueous metal solution are provided. The metal aqueous solution treatment system comprises a solid-liquid separation device and an adsorption device. The solid-liquid separation device separates the aqueous metal solution into a metal precipitate and treated water. The adsorption device is arranged at the downstream of the solid-liquid separation device and is filled with adsorption particles so as to adsorb metal ions in the treated water. The solid-liquid separation device sequentially comprises a settling tank, a buffer pipe and a solid collecting barrel.

Description

Technical Field

[0001] This application relates to an aqueous solution treatment system and a method for treating an aqueous solution, and particularly to a metal aqueous solution treatment system and a method for treating a metal aqueous solution. Background Art

[0002] The domestic electronics industry is developed, and there is a huge demand for the treatment of metal-containing process water generated by metal processing processes. Traditional treatment methods, such as chemical coagulation treatment, often have the following problems, which lead to low treatment efficiency and the risk of not meeting environmental protection regulations: 1. The precipitated sludge is easily disturbed and floats up, polluting the post-treatment section, so the influent flow rate is restricted. 2. The sedimentation efficiency of suspended solids is poor, so an organic coagulant is added to promote precipitation, but at the same time, unrecoverable waste sludge and water resources are generated. 3. The maintenance rate of the sludge scraping equipment is high.

[0003] Therefore, developing a method that can effectively recover metal substances in metal wastewater and at the same time can recycle the treated metal and water resources in a valuable way is an urgent problem for current researchers to solve. Summary of the Invention

[0004] This application provides a metal aqueous solution treatment system, which can effectively separate valuable metal precipitates and produce recycled water for recycling.

[0005] This application provides a method for treating a metal aqueous solution, which can effectively separate valuable metal precipitates and produce recycled water for recycling.

[0006] The metal aqueous solution treatment system of this application includes a solid-liquid separation device and an adsorption device. The solid-liquid separation device separates the metal aqueous solution into metal precipitates and treated water. The adsorption device is arranged downstream of the solid-liquid separation device and filled with adsorption particles to adsorb metal ions in the treated water. The solid-liquid separation device sequentially includes a sedimentation tank, a buffer pipe, and a solid collection bucket. The sedimentation tank has a feed port, a treated water outlet, and a lower end precipitate outlet, and the treated water is introduced into the adsorption device through the treated water outlet. The buffer pipe has a top opening and a bottom opening, and the top opening is connected to the lower end precipitate outlet of the sedimentation tank, and the metal precipitate solution containing metal precipitates is introduced into the buffer pipe through the lower end precipitate outlet. The solid collection bucket is connected to the bottom opening of the buffer pipe for collecting the metal precipitates of the metal precipitate solution flowing out of the buffer pipe.

[0007] The method for treating a metal aqueous solution of this application includes the following steps. Provide a metal aqueous solution treatment system liquid. Introduce the metal aqueous solution into the solid-liquid separation device of the metal aqueous solution treatment system to separate metal precipitates and treated water. Introduce the treated water into the adsorption device of the metal aqueous solution treatment system to remove metal ions in the treated water.

[0008] Based on the above, in the metal aqueous solution treatment system of the present application, valuable metal precipitates can be separated without adding a flocculant. In addition, since a buffer tube with a buffering function is provided between the sedimentation tank and the solid collection bucket, the liquid flowing out of the sedimentation tank can be prevented from directly impacting the deposited metal precipitates and causing them to resuspend, thereby improving the recovery rate and purity of the valuable metal precipitates. Furthermore, the adsorption device provided downstream of the solid-liquid separation device in the present application can further adsorb metal ions remaining in the treated water, whereby recycled water that can be recycled can be obtained.

[0009] To make the above features and advantages of the present application more obvious and understandable, specific embodiments are hereinafter given and described in detail in conjunction with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a block diagram of a metal aqueous solution treatment system 10 according to an embodiment of the present application.

[0011] Figure 2 It is a schematic diagram of a solid-liquid separation device 100 according to an embodiment of the present application.

[0012] Figure 3 It is a schematic diagram of an adsorption device 200 according to an embodiment of the present application.

[0013] Figure 4 It is a block diagram of a metal aqueous solution treatment system 10a according to another embodiment of the present application.

[0014] Figure 5 It is a block diagram of a metal aqueous solution treatment system 10b according to still another embodiment of the present application.

[0015] Figure 6 It is a flowchart of a method for treating a metal aqueous solution according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] Specific embodiments are hereinafter listed and described in detail in conjunction with the accompanying drawings, but the provided embodiments are not intended to limit the scope covered by the present application.

[0017] The terms "comprising", "including", "having", etc. mentioned in this article are all open-ended terms, that is, "including but not limited to".

[0018] In addition, in this article, the range represented by "one numerical value to another numerical value" is a summary representation method to avoid listing all the numerical values in the range one by one in the specification. Therefore, the description of a specific numerical range covers any numerical value within the said numerical range, as well as a smaller numerical range defined by any numerical value within the said numerical range.

[0019] In an embodiment of the present application, the metal aqueous solution treatment system includes a solid-liquid separation device and an adsorption device. Through the solid-liquid separation device, the metal precipitates in the metal aqueous solution can be effectively separated, and the recovery rate of valuable metal precipitates reaches more than 95%. In addition, after separating the metal precipitates in the metal aqueous solution, the remaining treated water can remove the metal ions remaining in the treated water through the adsorption device, thereby obtaining recycled water that can be recycled, and the metal ion removal rate reaches more than 99%. Therefore, the value of the full cycle of resources in the metal aqueous solution can be explored. The metal aqueous solution treatment system and method of the embodiments of the present application will be described in detail below.

[0020] Figure 1 FIG. is a block diagram of a metal aqueous solution treatment system 10 according to an embodiment of the present application. Please refer to Figure 1 , the metal aqueous solution treatment system 10 of the embodiment of the present application includes a solid-liquid separation device 100 and an adsorption device 200. In addition, depending on actual needs, the metal aqueous solution treatment system 10 may further include a pretreatment device 300, a filtration device 400, and a filtration device 500. The metal aqueous solution treatment system 10 is used to treat an aqueous solution containing metal ions and / or metal precipitates.

[0021] Examples of the water to be treated (i.e., the metal aqueous solution) in the present application may include: electroplating factory drainage, chemical factory drainage, metal refining factory drainage, metal surface treatment factory drainage, precious metal mining drainage, etc. The metal ions in the metal aqueous solution may include metal ions such as lead, copper, chromium, cadmium, nickel, or zinc. The metal precipitates in the metal aqueous solution may include various metal hydroxides or metal carbonate compounds. In one embodiment, the metal precipitate may be a metal precipitate formed by the above metal ions.

[0022] When the metal aqueous solution treatment system 10 includes a pretreatment device 300, the metal aqueous solution containing metal ions and / or metal precipitates can be first provided to the pretreatment device 300 for pretreatment, and the solid-liquid separation device 100 is disposed downstream of the pretreatment device 300 and is coupled to the pretreatment device 300.

[0023] The pretreatment device 300 can perform pretreatment on the metal aqueous solution containing metal ions and / or metal precipitates so that the metal ions in the metal aqueous solution form metal precipitates. The resulting solid metal precipitates can be further separated by the solid-liquid separation device 100.

[0024] In one embodiment, the pretreatment device 300 may include a pH adjustment device (not shown). The pH adjustment device may adjust the pH of the aqueous metal solution. In this embodiment, the pH value of the aqueous metal solution may be adjusted to 4 to 9 for facilitating the formation of metal precipitates by metal ions, but the present application is not limited thereto. Those skilled in the art may determine the most appropriate pH value according to the type of the aqueous metal solution to be treated.

[0025] In one embodiment, the pH adjustment may be implemented by supplying a pH adjuster (such as an acidic solution or an alkaline solution) to the aqueous metal solution. In one embodiment, the pH adjustment device may include an acidic solution supply device, an alkaline solution supply device, or a combination thereof. The acidic solution is, for example, hydrochloric acid, sulfuric acid, or other suitable inorganic acids. The alkaline solution is, for example, sodium hydroxide, calcium hydroxide, or other suitable inorganic bases.

[0026] In one embodiment, the pretreatment device 300 may further include an oxidizing / reducing agent supply device (not shown). The oxidizing / reducing agent supply device may supply an oxidizing agent or a reducing agent to the aqueous metal solution to facilitate the formation of metal precipitates by metal ions in the aqueous metal solution. In one embodiment, the pretreatment device 300 may perform a cyanide-breaking treatment on the cyanide-containing aqueous metal solution.

[0027] The solid-liquid separation device 100 is disposed downstream of the pretreatment device 300 and is coupled to the pretreatment device 300 to receive the aqueous metal solution from the pretreatment device 300. After the aqueous metal solution is pretreated by the pretreatment device 300, most of the metal ions in the aqueous metal solution have formed solid metal precipitates. Therefore, the aqueous metal solution can be further separated into metal precipitates and treated water by the solid-liquid separation device 100.

[0028] Figure 2 It is a schematic diagram of the solid-liquid separation device 100 according to an embodiment of the present application. In this embodiment, the solid-liquid separation device 100 is a three-stage solid-liquid separation device. Please refer to Figure 2 , the solid-liquid separation device 100 sequentially includes a sedimentation tank 110, a buffer pipe 120, and a solid collection bucket 130. The sedimentation tank 110 has a feed inlet 112, a treated water outlet 114, and a lower sediment outlet 116. The solid-liquid separation device 100 is coupled to the pretreatment device 300 through the feed inlet 112, and the solid-liquid separation device 100 is coupled to the adsorption device 200 (in the case of no filtration device 400) or the filtration device 400 through the treated water outlet 114. The aqueous metal solution containing metal ions and / or metal precipitates can be introduced into the sedimentation tank 110 through the feed inlet 112. The lower sediment outlet 116 may be disposed at the bottom of the sedimentation tank 110.

[0029] In the settling tank 110, gravity sedimentation can be directly utilized to perform solid-liquid separation on the aqueous metal solution without adding any flocculant. For example, by taking advantage of the difference in specific gravity between the metal precipitate and water in the aqueous metal solution, after the metal precipitate with a specific gravity greater than that of water has settled, the upper liquid is taken as the treated water, thereby separating the aqueous metal solution into a metal precipitate solution containing the metal precipitate and the treated water. The metal precipitate solution that has settled to the bottom of the settling tank 110 can be introduced into the buffer pipe 120 via the lower precipitate outlet 116.

[0030] In one embodiment, the feed inlet 112 and the treated water outlet 114 are provided at the upper end of the settling tank 110, and the vertical horizontal height of the feed inlet 112 is higher than the vertical horizontal height of the treated water outlet 114. When the treated water outlet 114 is provided below the feed inlet 112, it can ensure that the treated water can flow out smoothly from the treated water outlet 114 and prevent the metal precipitate from flowing out through the treated water outlet 114.

[0031] In one embodiment, the settling tank can be a tank body that is wider at the top and narrower at the bottom. In this embodiment, the shape of the settling tank 110 can be a tank body that is wider at the top and narrower at the bottom. For example, the settling tank 110 can be conical. The conical shape can cause the water flow to generate a swirling flow by inertia, thereby increasing the sedimentation rate of the metal precipitate. However, the settling tank 110 used in this application is not limited to the above shape and can also be other shapes.

[0032] The buffer pipe 120 has a top opening 122 and a bottom opening 124, where the top opening 122 is connected to the lower precipitate outlet 116 of the settling tank 110, and the metal precipitate solution containing the metal precipitate is introduced into the buffer pipe 120 via the lower precipitate outlet 116.

[0033] In this embodiment, the buffer pipe 120 has a buffering function to prevent the liquid flowing out from the lower precipitate outlet 116 of the settling tank 110 from directly impacting the metal precipitate collected in the solid collection bucket 130 (i.e., reducing the disturbance caused by the liquid and causing the deposited solid metal precipitate to be suspended again), thereby increasing the recovery rate of the valuable metal precipitate.

[0034] In one embodiment, the length L of the buffer pipe is 10 cm to 200 cm. In one embodiment, the aperture diameter D of the lower precipitate outlet 116 of the settling tank 110 b is 3 cm to 12 cm. In one embodiment, the ratio of the length L of the buffer pipe 120 to the aperture diameter D of the lower precipitate outlet 116 of the settling tank 110 b is (L / D b ) is 0.8 to 65. In another embodiment, the ratio of the length L of the buffer pipe 120 to the aperture diameter D of the lower precipitate outlet 116 of the settling tank 110 b is (L / Db ) is from 3 to 30. When L / D b is within the above range, the water flow impact can be effectively reduced and a steady flow (laminar flow) can be generated. When L / D b is lower than 0.8, there will be a problem that the liquid directly impacts the metal precipitate collected in the solid collection bucket (i.e., it is easy to cause disturbance). When L / D b is higher than 65, there is an easy problem of blockage of the buffer tube by metal precipitates.

[0035] In an embodiment, the buffer tube 120 may include a straight tube or a bent tube. In an embodiment, the buffer tube 120 is a bent tube, and the length L of the buffer tube is defined as the vertical distance from the top opening to the bottom opening of the buffer tube.

[0036] In this embodiment, the solid collection bucket 130 is connected to the bottom opening 124 of the buffer tube 120 for collecting the metal precipitate in the metal precipitation solution flowing out of the buffer tube 120. In an embodiment, the solid collection bucket 130 has a transparent window, which is conducive to directly visually monitoring the accumulation status of the metal precipitate. In an embodiment, the solid collection bucket 130 may include a filter 132 for separating the metal precipitation solution into a filtrate and a metal precipitate. The filter 132 is, for example, a screen filter, which can filter the filtrate to the bottom of the solid collection bucket 130 and collect the metal precipitate on the filter screen. In an embodiment, the filtrate separated by the filter 132 can be recycled and introduced back into the sedimentation tank 110, so as to further improve the separation efficiency of the metal precipitate.

[0037] In an embodiment, the treated water in the sedimentation tank 110 can be directly introduced into the adsorption device 200 through the treated water outlet 114. And in the embodiment as shown in Figure 1 , when the metal aqueous solution treatment system 10 further includes a filtering device 400, the treated water in the sedimentation tank 110 can be introduced into the filtering device 400 through the treated water outlet 114. The filtering device 400 is arranged downstream of the solid-liquid separation device 100 and upstream of the adsorption device 200. The filtering device 400 can remove the residual metal precipitate in the treated water to avoid blocking the adsorption device 200 by the residual metal precipitate. In an embodiment, the filtering device 400, for example, includes a screen filter or a fiber filter cloth.

[0038] In an embodiment, the solid-liquid separation device 100 may further include a quick-release component 126. The quick-release component 126 is arranged between the buffer tube 120 and the solid collection bucket 130. The setting of the quick-release component 126 can replace the full solid collection bucket in real time without shutting down the machine.

[0039] In one embodiment, the solid-liquid separation device 100 may further include a quick-release assembly 128. The quick-release assembly 128 is disposed between the buffer pipe 120 and the sedimentation tank 110. The provision of the quick-release assembly 128 enables the rapid replacement of the buffer pipe.

[0040] Figure 3 Schematic diagram of the adsorption device 200 according to an embodiment of the present application. Please refer to Figure 3 , the adsorption device 200 is disposed downstream of the solid-liquid separation device 100 and filled with adsorption particles 202.

[0041] In one embodiment, the adsorption device 200 includes a water inlet pipe 204 and a dispersion plate (not shown) located at the bottom of the adsorption device 200. The water inlet pipe 204 extends to the bottom of the adsorption device 200 and is connected to the dispersion plate. Thus, the water inlet pipe 204 can introduce the treated water to the bottom of the adsorption device 200 and discharge the treated water via the dispersion plate. The adsorption particles 202 filled in the adsorption device 200 can adsorb metal ions in the treated water.

[0042] In one embodiment, the adsorption particles 202 include activated carbon, glass pore adsorption material, or ion exchange resin. In one embodiment, the particle size of the adsorption particles 202 is from 200 μm to 10,000 μm. In one embodiment, the D 90 / D 10 particle size uniformity is 1 to 8, where D 90 means that 90% by weight of the adsorption particles in the adsorption device can pass through the aperture of the sieve, and D 10 means that 10% by weight of the adsorption particles in the adsorption device can pass through the aperture of the sieve. When the D 90 / D 10 particle size uniformity of the adsorption particles 202 is within the above range, the coefficient of variation (CV) of the metal ion adsorption can be 5% or less (i.e., the adsorption uniformity is good), and the removal rate of the metal ions can be 99% or more. More specifically, when the D 90 / D 10 particle size uniformity of the adsorption particles 202 is within the above range, the difference in the gap size between particles can be reduced, thereby reducing the pressure difference between the upper and lower positions of the local part of the adsorption device 200, avoiding the occurrence of the phenomenon of uneven flow, and improving the adsorption uniformity and adsorption effect of the materials in the system.

[0043] Through the above process, the adsorption device 200 can separate the metal ions in the treated water from the water to obtain recycled water. In addition, the obtained recycled water can be recycled. In addition, the valuable metal precipitates collected by the solid-liquid separation device of the present application can also be recycled to achieve the value of full resource recycling.

[0044] In one embodiment, when the metal aqueous solution treatment system 10 further includes a filtration device 500, the recycled water in the adsorption device 200 can be further introduced into the filtration device 500. The filtration device 500 is disposed downstream of the adsorption device 200. The filtration device 500 can remove the suspended solids and impurities generated due to the breakage of the adsorption material 202 in the recycled water. In one embodiment, the filtration device 500 includes, for example, a screen filter or a fiber filter cloth.

[0045] It should be noted here that in the following embodiments, the component numbers and some contents of the foregoing embodiments are followed. The same numbers are used to represent the same or similar components, and the description of the same technical content is omitted. For the description of the omitted parts, reference can be made to the foregoing embodiments, and the following embodiments will not be repeated.

[0046] Figure 4 It is a block diagram of a metal aqueous solution treatment system 10a according to another embodiment of the present application. Figure 4 The metal aqueous solution treatment system 10a and Figure 1 The same components of the metal aqueous solution treatment system 10 are represented by the same component symbols. Figure 4 The metal aqueous solution treatment system 10a and Figure 1 Compared with the metal aqueous solution treatment system 10, the metal aqueous solution treatment system 10a of the present application has an additional configuration of a solid-liquid separation device 100a. Specifically, please refer to Figure 4 , the metal aqueous solution treatment system 10a of the embodiment of the present application further includes an additional solid-liquid separation device 100a disposed downstream of the solid-liquid separation device 100 and upstream of the adsorption device 200. The additional solid-liquid separation device 100a is used to further separate the residual metal precipitates in the treated water treated by the solid-liquid separation device 100 to improve the recovery rate of valuable metal precipitates.

[0047] In one embodiment, the solid-liquid separation device 100 and the additional solid-liquid separation device 100a can be directly connected in series. In another embodiment, other filtration devices can be further provided between the solid-liquid separation device 100 and the additional solid-liquid separation device 100a.

[0048] In one embodiment, the additional solid-liquid separation device 100a sequentially includes an additional sedimentation tank 110a, an additional buffer pipe 120a, and an additional solid collection bucket 130a. The treated water after being processed by the solid-liquid separation device 100 can be introduced into the additional solid-liquid separation device 100a through the treated water outlet 114, and the treated water after being processed by the additional solid-liquid separation device 100a is introduced into the adsorption device 200 located downstream thereof through an additional treated water outlet (not shown) of the additional sedimentation tank 110a. When the metal aqueous solution treatment system 10a further includes a filtration device 400, the treated water in the additional sedimentation tank 110a can be introduced into the filtration device 400 through a treated water outlet (not shown). The filtration device 400 is disposed downstream of the additional solid-liquid separation device 100a and upstream of the adsorption device 200.

[0049] Figure 5 FIG. is a block diagram of a metal aqueous solution treatment system 10b according to another embodiment of the present application. Figure 5 The metal aqueous solution treatment system 10b and Figure 4 The same components of the metal aqueous solution treatment system 10a are denoted by the same component symbols. Figure 5 The metal aqueous solution treatment system 10b and Figure 4 Compared with the metal aqueous solution treatment system 10a of Figure 5 The metal aqueous solution treatment system 100 and the additional solid-liquid separation device 100b share the same solid collection bucket 130. Specifically, referring to Figure 5 , the metal aqueous solution treatment system 10b of the embodiment of the present application further includes an additional solid-liquid separation device 100b disposed downstream of the solid-liquid separation device 100 and upstream of the adsorption device 200. The additional solid-liquid separation device 100b is used to further separate the residual metal precipitates in the treated water after being processed by the solid-liquid separation device 100, so as to improve the recovery rate of valuable metal precipitates.

[0050] In one embodiment, the solid-liquid separation device 100 and the additional solid-liquid separation device 100b can be directly connected in series. In another embodiment, other filtration devices can be further disposed between the solid-liquid separation device 100 and the additional solid-liquid separation device 100b.

[0051] In one embodiment, the additional solid-liquid separation device 100b sequentially includes an additional sedimentation tank 110b and an additional buffer pipe 120b. The treated water processed by the solid-liquid separation device 100 can be introduced into the additional solid-liquid separation device 100b through the treated water outlet 114, and the treated water processed by the additional solid-liquid separation device 100b is introduced into the adsorption device 200 located downstream thereof through an additional treated water outlet (not shown) of the additional sedimentation tank 110b. When the metal aqueous solution treatment system 10b further includes a filtration device 400, the treated water in the additional sedimentation tank 110b can be introduced into the filtration device 400 through a treated water outlet (not shown). The filtration device 400 is disposed downstream of the additional solid-liquid separation device 100b and upstream of the adsorption device 200.

[0052] In one embodiment, the additional buffer pipe 120b of the additional solid-liquid separation device 100b can be connected to the solid collection bucket 130 of the solid-liquid separation device 100. That is to say, the metal aqueous solution treatment system 10b and the additional solid-liquid separation device 100b share the same solid collection bucket 130. In one embodiment, the buffer pipe 120 and the additional buffer pipe 120b can each be a bent pipe, which helps to connect to the same solid collection bucket.

[0053] In the traditional chemical coagulation system, the removal effect of metal substances in metal wastewater is unstable, and it has the following problems: (1) The metal precipitate is resuspended due to water flow disturbance, so that the metal precipitate may flow out into the environment and the process also limits the treatment rate. (2) In order to accelerate the sedimentation of metal precipitates, coagulants are added in the traditional wastewater treatment system, but at the same time, the purity of the metal precipitate is reduced to become a worthless waste.

[0054] However, based on the above embodiments, it can be seen that in the metal aqueous solution treatment system of the present application, coagulants can be added in small amounts or even without adding coagulants to separate metal precipitates. In addition, since a buffer pipe with a buffer function is provided between the sedimentation tank and the solid collection bucket, the liquid flowing out of the sedimentation tank can be prevented from directly impacting the metal precipitate, thereby improving the recovery rate and purity of the valuable metal precipitate. Furthermore, the adsorption device provided downstream of the solid-liquid separation device in the present application can further adsorb metal ions in the treated water, whereby recycled water that can be recycled can be obtained.

[0055] Next, use Figure 6 to illustrate a method for treating a metal aqueous solution according to an embodiment of the present application.

[0056] Figure 6 is a flowchart of a method for treating a metal aqueous solution according to an embodiment of the present application. Please refer to Figure 6 , first, in step S100, a metal aqueous solution treatment system is provided. In Figure 6 embodiments,Figure 1 a metal aqueous solution treatment system 10, but the present application is not limited thereto. In other embodiments, the method for treating metal aqueous solutions of the present application can also be applied to Figure 4 or Figure 5 metal aqueous solution treatment systems 10a and 10b. The following will illustrate with Figure 1 the metal aqueous solution treatment system 10.

[0057] Next, in step S110, a metal aqueous solution containing metal ions and / or metal precipitates is provided to the pretreatment device 300 for pretreatment. In this step, metal ions in the metal aqueous solution can form metal precipitates. In one embodiment, the pretreatment is, for example, pH adjustment, oxidation / reduction treatment, or a combination of the above. In other embodiments, step S110 can be omitted according to actual needs.

[0058] Next, in step S120, the pretreated metal aqueous solution is introduced into the solid-liquid separation device 100 of the metal aqueous solution treatment system to separate the metal precipitates and the treated water in the metal aqueous solution. Specifically, the metal precipitates will settle through the sedimentation tank 110 into the buffer pipe 120 and further flow into the solid collection bucket 130.

[0059] Then, in step S130, the treated water obtained after being treated by the solid-liquid separation device 100 is introduced into the adsorption device 200 of the metal aqueous solution treatment system to remove metal ions in the treated water. Specifically, the adsorption device 200 can separate the metal ions in the treated water from the water to obtain recycled water.

[0060] After that, in step S140, the metal precipitates are recovered from the solid collection bucket 130 of the solid-liquid separation device 100 and the recycled water is recovered from the adsorption device 200. In this way, the recovered recycled water can be recycled, and the recovered valuable metal precipitates can also be recycled to achieve the value of full resource circulation.

[0061] In one embodiment, any liquid (such as treated water, filtrate, recycled water) obtained in step S120, step S130, and / or step S140 can be re-repeated steps 120 to 140. In this way, the separation efficiency of metal precipitates can be further improved.

[0062] The following will illustrate the metal aqueous solution treatment system and method of the present application with experimental examples and comparative examples, and the treatment results are shown in Table 1.

[0063] Example 1

[0064] Experimental Example 1 was tested using the process waste liquid from an electroplating factory. First, the copper pyrophosphate process waste liquid with a concentration of 45.6 ppm was transported to an acid-base adjustment tank (i.e., a pH adjustment device) at a flow rate of 12.5 L / min for pretreatment to generate metal suspended solids. Then, the pretreated process waste liquid was introduced into a three-section solid-liquid separation device to sediment-separate the metal suspended solids from the treated water, where the ratio of the buffer tube length (L) to the bottom outlet aperture (D b ) of the three-section solid-liquid separation device was 0.9. As the process waste liquid entering the sedimentation tank rose, it overflowed from the treated water outlet of the sedimentation tank to the filter to intercept the remaining metal suspended solids. Then, the treated water filtered by the filter was led from the water inlet pipe at the upper end of the adsorption tower tank (adsorption device) to the dispersion plate at the bottom of the adsorption tower tank, and the water flow passed upward through the glass hole adsorption material (adsorption particles; the filling particle size was about 10,000 μm and the D 90 / D 10 ) with a particle size uniformity of about 1 to the upper outlet hole, so as to further adsorb and remove trace metal ions in the treated water and recover the treated recycled water.

[0065] Example 2

[0066] The treatment was carried out using a method similar to that of Example 1, the difference being that the concentration of the copper pyrophosphate waste liquid in Example 2 was 21.5 ppm and the flow rate was 15 L / min; the ratio of the buffer tube length (L) to the bottom outlet aperture (D b ) of the three-section solid-liquid separation device was 29.4; the particle size distribution of the glass hole adsorption material in the adsorption tower tank was in the range of 210 μm to 2000 μm, and the D 90 / D 10 ) had a particle size uniformity of 7.9.

[0067] Example 3

[0068] The treatment was carried out using a method similar to that of Example 1, the difference being that the concentration of the copper pyrophosphate waste liquid in Example 3 was 16.0 ppm and the flow rate was 14.7 L / min; the ratio of the buffer tube length (L) to the bottom outlet aperture (D b ) of the three-section solid-liquid separation device was 62.5; the particle size distribution of the glass hole adsorption material in the adsorption tower tank was in the range of 250 μm to 1003 μm, and the D 90 / D 10 ) had a particle size uniformity of 6.7.

[0069] Example 4

[0070] Experimental Example 4 was tested using the process waste liquid from an electroplating factory. First, the copper cyanide process waste liquid with a concentration of 241 ppm was transported to the cyanide removal treatment tank at a flow rate of 12.0 L / min for two-stage cyanide destruction treatment continuously. Then, the treated process waste liquid was transported to the acid-base adjustment tank (i.e., pH adjustment device) for pretreatment to generate metal suspended solids. Next, the pretreated process waste liquid was introduced into a three-section solid-liquid separation device to sediment and separate the metal suspended solids from the treated water, where the ratio of the buffer tube length (L) of the three-section solid-liquid separation device to the bottom outlet aperture diameter (D b ) was 0.9. As the process waste liquid entering the sedimentation tank rose, it overflowed from the treated water outlet of the sedimentation tank to the filter to intercept the remaining metal suspended solids. Then, the treated water filtered by the filter was led from the water inlet pipe at the upper end of the adsorption tower tank (adsorption device) to the dispersion plate at the bottom of the adsorption tower tank, and the water flow passed upward through the glass hole adsorption material (adsorption particles; the filling particle size was about 250 μm to 1003 μm and the D 90 / D 10 particle size uniformity was about 6.7) to the upper outlet hole, so that trace metal ions in the treated water were further adsorbed and removed and the treated recycled water was recovered.

[0071] Example 5

[0072] The treatment was carried out using a method similar to that of Example 1, except that the waste liquid in Example 5 was nickel sulfate waste liquid (298.5 ppm), and the flow rate was 17 L / min; the ratio of the buffer tube length (L) of the three-section solid-liquid separation device to the bottom outlet aperture diameter (D b ) was 29.4; the particle size distribution of the glass hole adsorption material in the adsorption tower tank was in the range of 250 μm to 1003 μm, and the D 90 / D 10 particle size uniformity was 6.7.

[0073] Example 6

[0074] The treatment was carried out using a method similar to that of Example 4, except that the concentration of the copper cyanide process waste liquid in Example 6 was 251.3 ppm, and the flow rate was 10.0 L / min; the ratio of the buffer tube length (L) of the three-section solid-liquid separation device to the bottom outlet aperture diameter (D b ) was 29.4; the particle size distribution of the glass hole adsorption material in the adsorption tower tank was in the range of 250 μm to 1003 μm, and the D 90 / D 10 particle size uniformity was 6.7.

[0075] Comparative Example 1

[0076] The treatment was carried out using a method similar to that of Example 1, except that Comparative Example 1 did not have a buffer tube for the solid-liquid separation device; the concentration of the copper pyrophosphate waste liquid was 12.9 ppm; the particle size distribution of the glass pore adsorbent material in the adsorption tower tank was in the range of 250 μm to 2360 μm, and the uniformity of the particle size of D 90 / D 10 was 9.4.

[0077] Comparative Example 2

[0078] The treatment was carried out using a method similar to that of Example 1, except that the concentration of the copper pyrophosphate waste liquid in Comparative Example 2 was 38.1 ppm; the particle size distribution of the glass pore adsorbent material in the adsorption tower tank was in the range of 210 μm to 2812 μm, and the uniformity of the particle size of D 90 / D 10 was 11.2.

[0079] Comparative Example 3

[0080] First, the copper pyrophosphate waste liquid with a concentration of 24.3 ppm was transported to the acid-base adjustment tank at a flow rate of 13.5 L / min for acid-base neutralization treatment. Then, the treated process waste liquid was sequentially transported to the heavy metal reaction tank, the coagulation tank, and the gelling tank, and a capturing agent and a coagulant aid were added during the process to gel-aggregate the metal ions. Finally, the solid / liquid was transported to a traditional sedimentation tank for sedimentation separation.

[0081] The examples and comparative examples were evaluated for the properties shown in Table 1.

[0082] A. Particle size uniformity

[0083] Method: Take Tyler standard sieves #7, #9, #10, #16, #20, #32, #48, #60, #65, #80, arrange them in an overlapping manner from small to large number, and place the material on the topmost sieve (#7), and perform sieving through a shaker.

[0084] Calculation method:

[0085] Where

[0086] D 10 : The aperture of the sieve through which 10% by weight of the adsorbent in the adsorption tower can pass.

[0087] D 90 : The aperture of the sieve through which 90% by weight of the adsorbent in the adsorption tower can pass.

[0088] The calculation is as follows:

[0089] 1. First, calculate the weight percentage remaining on the nth sieve (n is counted from the top downwards)

[0090]

[0091] 2. Then calculate the cumulative percentage passing through n sieves

[0092]

[0093] where D 10 is the aperture of the nth sieve corresponding to

[0094] D 90 is the aperture of the nth sieve corresponding to

[0095] B. Recovery rate of valuable metal precipitate

[0096] Calculation method:

[0097]

[0098] C. Adsorption deviation (CV)

[0099] Calculation method:

[0100]

[0101] Method: At the same height above the adsorption column, sample 10 points of the adsorption material evenly and disperse them. Analyze the metal adsorption content (mg / g) in the material by Inductively Coupled Plasma Optima Optical Emission Spectrometer (ICP-OES). Then calculate the standard deviation and average value of the 10 points.

[0102] D. Metal ion removal rate

[0103] Calculation method:

[0104]

[0105] Method: Take the metal waste liquid at the inlet and outlet and detect the metal ion concentration by ICP-OES.

[0106] E. Purity of valuable metal precipitate

[0107] Calculation method:

[0108]

[0109] Method: Take the metal precipitate in the solid collection bucket, dry it, weigh it, and detect the metal ion content by ICP-OES.

[0110] Table 1

[0111]

[0112] As can be seen from Table 1 above, in Examples 1 to 6 of the metal aqueous solution treatment system and the method for treating a metal aqueous solution of the present application, valuable metal precipitates in the process waste liquid can be effectively separated, and the recovery rate of the valuable metal precipitates can be increased from 75% of the traditional method to over 95%, and the purity of the valuable metal precipitates can be improved. In addition, in Examples 1 to 6 of the present application, metal ions in the process waste liquid can be effectively removed, thereby obtaining recycled water that can be recycled, and the metal ion removal rate reaches over 99%.

[0113] On the contrary, in Comparative Example 1 (without the buffer tube of the present application and the particle size uniformity is higher than 8) and Comparative Example 2 (the particle size uniformity is higher than 8), the recovery rate of the valuable metal precipitates, the metal ion removal rate, and the purity of the valuable metal precipitates are all not good. In Comparative Example 3, due to the use of a polymer coagulant for coagulation treatment, the liquid in the process waste liquid cannot recover the valuable metal precipitates and the recycled water because it contains a large amount of solid polymer substances.

[0114] Although the present application has been disclosed above by way of examples, it is not intended to limit the present application. Those skilled in the art should be able to make some modifications and refinements without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application should be defined by the appended claims.

Claims

1. A metal aqueous solution treatment system, characterized in that, it comprises: a solid-liquid separation device for separating the metal aqueous solution into metal precipitates and treated water; and an adsorption device disposed downstream of the solid-liquid separation device and filled with adsorption particles to adsorb metal ions in the treated water, wherein the solid-liquid separation device sequentially comprises: a sedimentation tank having a feed inlet, a treated water outlet and a lower sediment outlet at the bottom, wherein the treated water is introduced into the adsorption device via the treated water outlet; a buffer pipe having a top opening and a bottom opening, the top opening being connected to the lower sediment outlet of the sedimentation tank, wherein a metal precipitate solution containing the metal precipitates is introduced into the buffer pipe via the lower sediment outlet; and a solid collection bucket connected to the bottom opening of the buffer pipe for collecting the metal precipitates of the metal precipitate solution flowing out of the buffer pipe, wherein the ratio of the length of the buffer pipe to the aperture of the lower sediment outlet of the sedimentation tank is 0.8 to 65.

2. The metal aqueous solution treatment system according to claim 1, wherein the length of the buffer pipe is 10 cm to 200 cm.

3. The metal aqueous solution treatment system according to claim 1, wherein the aperture of the lower sediment outlet of the sedimentation tank is 3 cm to 12 cm.

4. The metal aqueous solution treatment system according to claim 1, wherein the feed inlet and the treated water outlet are provided at the upper end of the sedimentation tank, and the vertical horizontal height of the feed inlet is higher than the vertical horizontal height of the treated water outlet.

5. The metal aqueous solution treatment system according to claim 1, wherein the particle size of the adsorption particles is 200 μm to 10,000 μtm.

6. The metal aqueous solution treatment system according to claim 1, wherein the particle size uniformity of the adsorption particles D 90 / D 10 is 1 to 8.

7. The metal aqueous solution treatment system according to claim 1, wherein the adsorption particles include activated carbon, glass pore adsorption material or ion exchange resin.

8. The metal aqueous solution treatment system according to claim 1, further comprising a pretreatment device disposed upstream of the solid-liquid separation device, wherein the pretreatment device pretreats the metal aqueous solution so that the metal ions in the metal aqueous solution form the metal precipitates.

9. The metal aqueous solution treatment system according to claim 8, wherein the pretreatment device comprises a pH adjustment device, an oxidation / reduction agent supply device, or a combination thereof.

10. The metal aqueous solution treatment system according to claim 1, further comprising an additional solid-liquid separation device disposed downstream of the solid-liquid separation device and upstream of the adsorption device for separating residual metal precipitates in the treated water, wherein the additional solid-liquid separation device sequentially comprises an additional sedimentation tank, an additional buffer pipe and an additional solid collection bucket, the treated water is introduced into the additional solid-liquid separation device through the treated water outlet, and the treated water treated by the additional solid-liquid separation device is introduced into the adsorption device through the additional treated water outlet of the additional sedimentation tank.

11. The metal aqueous solution treatment system according to claim 1 further includes an additional solid-liquid separation device, which is arranged downstream of the solid-liquid separation device and upstream of the adsorption device for separating residual metal precipitates in the treated water. Wherein the additional solid-liquid separation device sequentially includes an additional sedimentation tank and an additional buffer pipe. The treated water is introduced into the additional solid-liquid separation device through the treated water outlet, and the treated water after being treated by the additional solid-liquid separation device is introduced into the adsorption device through the additional treated water outlet of the additional sedimentation tank, and wherein the additional buffer pipe is connected to the solid collection bucket of the solid-liquid separation device.

12. The metal aqueous solution treatment system according to claim 1, wherein the buffer pipe includes a straight pipe or a bent pipe.

13. The metal aqueous solution treatment system according to claim 1, wherein the solid-liquid separation device further includes a quick-release component, which is arranged between the buffer pipe and the solid collection bucket.

14. The metal aqueous solution treatment system according to claim 1, wherein the solid collection bucket includes a filter screen to separate the filtrate in the solid collection bucket and the metal precipitates.

15. The metal aqueous solution treatment system according to claim 1 further includes a filtration device, which is arranged downstream of the solid-liquid separation device and upstream of the adsorption device for removing residual metal precipitates in the treated water.

16. A method for treating a metal aqueous solution, characterized in that, comprising: providing the metal aqueous solution treatment system according to claim 1; introducing the metal aqueous solution into the solid-liquid separation device of the metal aqueous solution treatment system to separate the metal precipitates and the treated water; and introducing the treated water into the adsorption device of the metal aqueous solution treatment system to remove metal ions in the treated water.

17. The method for treating a metal aqueous solution according to claim 16, wherein before introducing the metal aqueous solution into the solid-liquid separation device, pretreatment is further included to form the metal ions in the metal aqueous solution into the metal precipitates.

18. The method for treating a metal aqueous solution according to claim 17, wherein the pretreatment includes pH adjustment, oxidation / reduction treatment, or a combination of the above.

19. The method for treating a metal aqueous solution according to claim 16 further includes recovering the metal precipitates and the recycled water after removing the metal ions in the treated water.

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