TWI570074B - Method for treating liquid wastes containing metal gallium - Google Patents

Description

Method for treating liquid waste containing metal gallium

The invention relates to a method for treating liquid waste containing metal gallium, in particular to a field belonging to environmental protection and effective recycling of waste resources, and aims to provide an effective recycling method for metal gallium containing liquid waste in photovoltaic industry, mainly By adjusting the difference between the pH value of the liquid waste, the temperature and the selectivity of the adsorbent material to the metal gallium, the liquid waste and the metal gallium can be effectively removed and separated to reduce the liquid waste content by 99% to provide an easy operation. A method that automates production, complies with environmental regulations, and more efficiently recovers metal gallium.

At present, the metal gallium used in the optoelectronic industry is a rare metal on the earth, but the methods and ways of production are only from the additional products derived from the production of metal aluminum, but the metal gallium was wasted in the process of the optoelectronic industry. Waste that becomes useless is discarded and discharged. In order to cope with the second item of Article 7 of the Water Pollution Prevention and Control Law to be implemented in the Republic of China in 102 years, the emission standard of a few precious metals should not exceed 0.1 ppm, so how to develop an effective method that can greatly reduce the pollution of a few precious metals, and Converting pollution into recycling resources with a view to improving economic efficiency and reducing social costs will be a very important goal at present.

The metal gallium waste produced by the optoelectronic industry in the process equipment is produced in addition to the liquid waste from the plant side, and there are solid and gaseous wastes generated at the equipment end. Therefore, the treatment of metal gallium-containing waste will follow Process changes and processing methods are different, resulting in liquid State, gaseous and solid waste, and the recycling process of liquid, gaseous and solid waste is different, which will also cause the difficulty of waste disposal.

Therefore, if a method for treating a liquid waste containing metal gallium can be established, it can be treated by physical means (such as condensation, adhesion, etc.) or by chemical means (such as dissolution, extraction, etc.) to discard the gaseous and solid forms. After the material is pretreated into the liquid waste of the factory, the liquid waste collected by the plant side is subjected to pH adjustment, temperature adjustment, filtration, chemical adsorption, desorption and post-treatment, etc., and the liquid waste is discharged. The separation of the metal gallium contained in the material from the unwanted elements, thereby reducing the pollution of the metal gallium in the liquid waste and achieving the purpose of resource reuse, should be an optimal solution.

The invention provides a method for treating a liquid waste containing metal gallium, which mainly utilizes the solubility of the gallium-containing solid waste to initially separate the solid waste containing gallium and no gallium, and then through pH adjustment, adsorption, Treatment procedures such as precipitation and filtration effectively separate arsenic from gallium to recover solutions that comply with environmental regulations and meet the smelting of metal gallium by refineries.

The method for treating the above-mentioned metal gallium-containing liquid waste can be achieved by the steps of: 1. detecting the pH value of the liquid waste, and then guiding it to an adjustment tank to adjust the pH value and temperature, and then proceeding Sampling to detect the concentration of metal gallium contained in the liquid waste; 2. Exporting the liquid waste with adjusted pH and temperature from the adjustment tank to a filter to adjust the suspended particles contained in the liquid waste The salt produced by the pH value is reduced to a minimum; 3. An adsorption tower is installed behind the filter, and a special adsorption material capable of adsorbing metal gallium is packed in the adsorption tower, and the liquid waste is flowed into the adsorption tower for adsorption in the liquid waste. Metal gallium; 4. After the adsorption, the liquid waste is discharged into an acid liquid storage tank, and the concentration of metal gallium contained in the liquid waste is detected.

More specifically, the pure water is added to the adjustment tank to adjust to a pH range of 1 to 5, and the temperature rise is adjusted to 40 to 60 ° C, and then sampling is performed to detect metal gallium contained in the liquid waste. concentration.

More specifically, the filter can be equipped with a flow rate device before and after to detect whether the filter is blocked.

More specifically, the special adsorbent material is activated carbon, activated aluminum, titanium oxide, iron hydroxide, ferric chloride or an amidoxime-containing, iminodiacetic acid cationic chelate resin.

More specifically, the liquid waste flows into the adsorption tower at a flow rate of about 1 to 20 times the adsorption column volume per hour to adsorb the metal gallium contained in the liquid waste.

More specifically, the concentration of metal gallium contained in the liquid waste in the acid storage tank can be reduced from the concentration of the metal-containing gallium before treatment to 1000-10000 ppm to 0.03 ppm.

More specifically, the metal gallium adsorbed by the special adsorbent can be eluted by the alkaline eluent and collected in a metal gallium eluent collection tank, and then the non-metal gallium in the eluate is removed. Impurities and elements, and then continue to add sodium hydroxide to increase the concentration of sodium hydroxide in the eluent to 80g / L ~ 160g / L, in line with the refinery can smelt metal gallium grade.

More specifically, the alkaline eluent is sodium hydroxide plus pure water to prepare a 1-20% sodium hydroxide solution.

More specifically, the liquid waste is collected from the gaseous waste containing metal gallium, and then the collected waste is dissolved into liquid waste by acid, and then the liquid waste is detected. The pH of the material and direct it to the conditioning tank.

More specifically, the method of collecting gaseous waste containing metal gallium is a condensation method or an attachment method.

More specifically, the liquid waste is collected from the solid waste containing metal gallium, and then the collected waste is dissolved into liquid waste by acid, and then the liquid waste is detected. The pH of the material and direct it to the conditioning tank.

More specifically, the liquid waste in the acid storage tank can be guided to an arsenic treatment tank to absorb the arsenic component of the liquid waste, and then the liquid metal containing no gallium and arsenic. The waste flows to a wastewater tank.

More specifically, the acid storage tank and the arsenic treatment tank have an automatic valve switch. If it is determined that the liquid waste in the acid storage tank does not have an arsenic component, the liquid waste can be directly flowed. Waste water tank.

〔this invention〕

201‧‧‧Adjustment slot

202‧‧‧pH adjustment module

203‧‧‧ Heating Module

204‧‧‧Acid adjustment tank

205‧‧‧ lye adjustment tank

206‧‧‧ pure sink

207‧‧‧Flower

208‧‧‧Filter

209‧‧‧Adsorption tower

210‧‧‧Metal gallium eluent collection tank

211‧‧‧ acid storage tank

212‧‧‧Automatic valve switch

213‧‧‧ arsenic treatment tank

214‧‧‧ Wastewater tank

3‧‧‧Factory side

4‧‧‧Gaseous Waste Treatment System

401‧‧‧Gaseous waste adsorption module

402‧‧‧Gaseous Waste Extraction Module

5‧‧‧Solid Waste Treatment System

501‧‧‧Solid Waste Extraction Module

1 is a schematic flow chart of a method for treating a liquid waste containing metal gallium according to the present invention.

Fig. 2 is a flow chart showing the first embodiment of the treatment method of the metal gallium-containing liquid waste of the present invention.

Fig. 3 is a flow chart showing the second embodiment of the treatment method of the metal gallium-containing liquid waste of the present invention.

Figure 4 is a third embodiment of the treatment process for a metal gallium-containing liquid waste according to the present invention. Cheng Tu.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

As shown in FIG. 1, the steps of the method for treating a liquid waste containing metal gallium according to the present invention are as follows: 1. Performing the detection of the pH value of the liquid waste, and then guiding it to an adjustment tank to adjust the pH thereof. Value and temperature, then sampling to detect the concentration of metal gallium contained in the liquid waste 101; 2. Exporting the liquid waste with adjusted pH and temperature to the filter through the adjustment tank, the liquid waste The suspended particles and the salt produced by adjusting the pH value are reduced to a minimum of 102; 3. An adsorption tower is installed behind the filter, and a special adsorption material capable of adsorbing metal gallium is filled in the adsorption tower, and The liquid waste is flowed into the adsorption tower to adsorb the metal gallium 103 contained in the liquid waste; 4. After the adsorption, the liquid waste is discharged into an acid liquid storage tank, and the liquid waste is detected. The concentration of metal gallium contained in the film is 104.

Since the photovoltaic industry processes different types of liquid wastes depending on process changes and treatment methods, the source of waste is different, and the above process is a process that has been converted into liquid waste, so if it is gaseous and solid waste, it must be The metal gallium contained in the liquid waste can be separated from the unwanted elements by pre-treatment into liquid waste, and the factory side in the first implementation has liquid waste containing metal gallium, as shown in Fig. 2. Show, so no pre-processing The process of directly charging the metal gallium-containing liquid waste generated in the photovoltaic industry process from the plant terminal 3 into the waste water plant before the pipeline; since the pH of the liquid waste is not fixed, it must be based on the pH value. The adjustment of the temperature adjusts the liquid waste to the optimal metal gallium adsorption state, so the pH value of the liquid waste is detected first, and then guided to an adjustment tank 201, and then the pH adjustment module 202 is used. The acid concentration adjusting tank 204, the alkali liquid adjusting tank 205 and the pure water tank 206 are adjusted to adjust the pH concentration to a pH value of 1 to 5, and the temperature is adjusted by the heating module 203 to about 40 to 60 ° C. And sampling and detecting the concentration of metal gallium contained in the liquid waste is about 50 ppm; after that, the liquid waste with the adjusted pH and temperature is led out from the adjusting tank 201 to a filter 208 for liquid waste. The suspended particles contained in the suspension and the salt produced by adjusting the pH value are minimized to avoid blocking of the subsequent treatment of the adsorbent material and affecting the adsorption effect; and the filter 208 is provided with a front and rear A flow rate 207 for filtering by flow rate detection Whether there is a blockage occurs; and an adsorption tower 209 is disposed behind the filter 208, and a special adsorbent material capable of adsorbing metal gallium is loaded in the adsorption tower 209, wherein the special adsorbent material can be activated carbon, active Aluminum, titanium oxide, iron hydroxide, ferric chloride or amidoxime, iminodiacetic acid cationic chelate resin, etc., and then flow into the adsorption at a flow rate of about 1 to 20 times per hour of adsorption column volume In the column 209, the metal gallium contained in the liquid waste is adsorbed. After the adsorption, the liquid waste is flowed into the acid storage tank 211, and the concentration of the metal gallium contained in the liquid waste is detected, and the concentration can be reduced from the concentration of the metal gallium before treatment to 50-10000 ppm to 0.03 ppm. From the left and right, it can be seen that the method can successfully remove more than 99% of the metal gallium contained in the liquid waste.

After the adsorption of the special adsorbent material is saturated, the metal gallium adsorbed on the special adsorbent material is desorbed by the analytical solution and the special adsorbent material is reduced, and the analytical solution is sodium hydroxide plus pure water (RO water). Prepare 1~20% sodium hydroxide solution to make alkaline eluent. Therefore, when the metal gallium contained in the special adsorbent is washed by the alkaline eluent, the metal gallium and special adsorption are achieved. The material is effectively separated, and the separated metal gallium is collected into a metal gallium eluent collection tank 210. At this time, the metal gallium contained in the alkaline eluent is about 2000 to 60000 ppm, when the purification standard is successfully achieved. After removing other unwanted impurities and elements in the solution, and then adding sodium hydroxide to increase the concentration of sodium hydroxide in the alkaline eluate to 80g/L~160g/L, it is in line with the refining metal that can be smelted by the refinery. The level of gallium.

In addition, the liquid waste in the acid storage tank 211 can be guided to an arsenic treatment tank 213 through an automatic valve switch 212 for absorbing the arsenic component in the liquid waste, and after the treatment is completed, The liquid waste containing metal gallium and arsenic flows to a waste water tank 214; however, if it is judged that the liquid waste in the acid liquid storage tank 211 does not have an arsenic component, the liquid waste can be directly discharged to the waste water tank 214.

In addition, since metal gallium cannot be left on the surface of the special adsorbent material, it will affect the effect of the next adsorption. Therefore, the special adsorbent in the adsorption tower 209 must be washed with pure water (RO water) to adjust the pH. Value to neutral and remove residual metal gallium on the surface of the special adsorbent material to meet the next adsorption standard.

Since the LED epitaxial process belongs to a high-temperature process, the metal-containing gallium waste produced by the LED is formed in the factory side 3 as a gaseous waste after the LED epitaxial process, as shown in FIG. 3, the second implementation must be First, through the physical means (such as condensation, adhesion, etc.), through the gaseous waste adsorption module 401 in a gaseous waste treatment system 4 and the gaseous waste extraction module The group 402 collects the gaseous metal-containing gallium waste generated by the plant terminal 3, and then detects the pH value of the liquid waste, and then guides it to an adjustment tank 201 to be adjusted by the pH adjustment module 202. The acid adjustment tank 204, the lye adjustment tank 205 and the pure water tank 206 are dissolved in a liquid waste with a solution of 1 to 6 M hydrochloric acid or nitric acid, and then the pH is adjusted to 1 to 5 by adding pure water (RO water). The range is adjusted by the heating module 203 to about 40~60 °C. At this time, the concentration of metal gallium contained in the liquid waste is about 1000~10000 ppm. The process of separating the liquid waste from the metal gallium in the second embodiment is the same as the first embodiment, and therefore will not be repeated.

In addition, when the LED epitaxial high-temperature process is carried out, the metal-containing gallium waste generated by the LED gallium waste will be present in the factory side 3 as a solid waste after the LED epitaxial process is cooled, as shown in Fig. 4. The third implementation collects the metal-containing gallium solid waste through the solid waste extraction module 501 in a solid waste treatment system 5, and then detects the pH value of the liquid waste and then guides it to a The tank 201 is adjusted to be dissolved in liquid waste by a solution of 1 to 6 M hydrochloric acid or nitric acid by the pH adjusting module 202, the acid adjusting tank 204, the alkali adjusting tank 205, and the pure water tank 206, and then pure water is added. (RO water) adjusts the pH value to a range of 1 to 5, and simultaneously adjusts the temperature to about 40 to 60 ° C by the heating module 203, and samples and detects the concentration of metal gallium contained in the liquid waste. It is around 50~10000ppm. The process of separating the liquid waste from the metal gallium in the third embodiment is the same as the first embodiment, and therefore will not be repeated.

In addition, the present invention is coupled to a central control system for controlling the operating parameters of the overall operation of the acid-base concentration difference, contact time, and contact flow rate of the analytical liquid for the purpose of effectively separating the metal gallium from the adsorbent material.

The invention provides a method for treating liquid waste containing metal gallium, and When other conventional techniques are compared with each other, the advantages are as follows:

1. The present invention provides a method for treating gallium containing metal gallium liquid waste, which mainly performs pH adjustment, temperature adjustment, filtration, chemical adsorption, desorption and post treatment of liquid waste collected at the factory side. The steps of separating the metal gallium contained in the liquid waste from the unnecessary elements, thereby reducing the pollution of the metal gallium in the liquid waste and achieving the purpose of resource reuse.

2. The present invention is an effective method capable of greatly reducing pollution of a small amount of precious metals, and can convert pollution into recycling resources, with a view to improving economic efficiency and reducing social costs.

The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed.

Claims (9)

A method for treating liquid waste containing metal gallium, the steps of: detecting the pH value of the liquid waste, and then guiding it to an adjustment tank to adjust the pH value and temperature, and then sampling and detecting the liquid waste The concentration of metal gallium contained in the substance; and the liquid waste whose pH and temperature have been adjusted are led out from the adjusting tank to a filter, and the suspended particles contained in the liquid waste and the salt produced by adjusting the pH value The class is reduced to a minimum; an adsorption tower is installed behind the filter, and a special adsorption material capable of adsorbing metal gallium is packed in the adsorption tower, and liquid waste is flowed into the adsorption tower for adsorption of liquid waste. The metal gallium contained therein; after the adsorption, the liquid waste is discharged into an acid liquid storage tank, and the concentration of the metal gallium contained in the liquid waste is detected, and the liquid waste contained in the acid liquid storage tank is contained The concentration of metal gallium can be reduced from the concentration of metal gallium before treatment to 1000-10000 ppm to 0.03 ppm. The method for treating a liquid waste containing metal gallium according to claim 1 , wherein the pure water is added to the adjustment tank to adjust to a pH range of 1 to 5, and the temperature is adjusted to 40 to 60. °C, after sampling to detect the concentration of metal gallium contained in the liquid waste. As one of the application of paragraph 1 patentable scope of the metal-containing aqueous waste processing method of the gallium, wherein the filter system can be installed before and after the flow rate, a filter configured to detect whether a blockage. The method for treating a metal gallium-containing liquid waste according to claim 1 , wherein the special adsorbent material is activated carbon, activated aluminum, titanium oxide, iron hydroxide, ferric chloride or amidoxime. Iminodiacetic acid cationic chelate resin. The method for treating a liquid waste containing metal gallium according to claim 1 , wherein the liquid waste flows into the adsorption tower at a flow rate of about 1 to 20 times the flow rate of the adsorption tower per hour for adsorption. Metal gallium contained in liquid waste. The method for treating a liquid waste containing metal gallium according to claim 1 of the patent application can be prepared by adding sodium hydroxide plus pure water to an alkaline eluent of 1 to 20% sodium hydroxide solution. The metal gallium adsorbed by the special adsorbent material is extracted and collected in a metal gallium eluent collection tank, and then the impurities and elements of the non-metal gallium in the eluate are removed, and then the sodium hydroxide is added to elute The concentration of sodium hydroxide in the liquid is increased to 80g/L~160g/L to meet the grade of metal gallium that the refinery can smelt. The method for treating a liquid waste containing metal gallium according to claim 1 , wherein the liquid waste is collected by a condensation method or a deposition method after the gaseous waste containing metal gallium is collected. The waste is dissolved into liquid waste by acid, and then the pH of the liquid waste is detected and directed to the adjustment tank. The method for treating a metal gallium-containing liquid waste according to claim 1 , wherein the liquid waste is collected from the solid waste containing metal gallium, and then the collected waste is treated with an acid liquid. Dissolve it as liquid waste, and then detect the pH of the liquid waste and direct it to the conditioning tank. The method for treating a liquid waste containing metal gallium according to claim 1 , wherein the acid storage tank and the arsenic treatment tank have an automatic valve switch, and if it is determined in the acid storage tank When the liquid waste does not have arsenic, the liquid waste can be directly discharged into the waste water tank. If the arsenic component is contained, the liquid waste can be guided to an arsenic treatment tank for arsenic component in the liquid waste. After being absorbed, the liquid waste containing no metal gallium and arsenic is discharged to a waste water tank.