CN-121992198-A - Recovery processing method for waste photovoltaic cell

Abstract

The invention relates to the technical field of photovoltaic cell recycling, in particular to a recycling method of waste photovoltaic cells. The recovery treatment method comprises the steps of (1) placing waste photovoltaic cell powder in an aluminum leaching agent for reaction, carrying out solid-liquid separation to obtain dealuminated cell powder and aluminum-containing leaching liquid, (2) placing the dealuminated cell powder in a silver leaching agent for reaction, carrying out solid-liquid separation to obtain dealuminated silver cell powder and silver-containing leaching liquid, carrying out electrolytic treatment on the silver-containing leaching liquid to obtain elemental silver and electrolyte, and (3) placing the dealuminated silver cell powder in a silicon purifying agent for reaction, and carrying out solid-liquid separation to obtain silicon powder, wherein the silver leaching agent is selected from a mixed aqueous solution containing 0.8-1.5 mol/L nitric acid and 0.05-0.15 mol/L hydrogen peroxide. The recovery processing method provided by the invention can realize the recovery of all resources of aluminum, silver and silicon, and the process flow is environment-friendly and has economic feasibility.

Inventors

• YANG ZHAOYI
• YU HONGBO
• ZHAO HAIJUN

Assignees

• 北京环球中科水务科技股份有限公司

Dates

Publication Date

20260508

Application Date

20251231

Claims (10)

1. 1. The recovery processing method of the waste photovoltaic cell is characterized by comprising the following steps of: (1) Placing the waste photovoltaic cell powder into an aluminum leaching agent for reaction, and carrying out solid-liquid separation to obtain dealuminized cell powder and aluminum-containing leaching liquid; (2) Placing the dealuminated battery powder into a silver leaching agent for reaction, carrying out solid-liquid separation to obtain dealuminated silver battery powder and silver-containing leaching liquid, and carrying out electrolytic treatment on the silver-containing leaching liquid to obtain elemental silver and electrolyte; (3) Placing the dealuminated silver battery powder into a silicon purifying agent for reaction, and carrying out solid-liquid separation to obtain silicon powder; Wherein the silver leaching agent is selected from mixed aqueous solution containing 0.8-1.5 mol/L nitric acid and 0.05-0.15 mol/L hydrogen peroxide.
2. 2. The recovery processing method according to claim 1, further comprising adding nitric acid to the electrolytic solution to obtain a regenerated silver leaching agent, and recycling the regenerated silver leaching agent to the step (2).
3. 3. The recovery treatment method according to claim 1 or 2, characterized in that the electrolytic treatment is performed in an electrolytic tank, the anode is titanium platinum alloy or titanium platinized, and the cathode is titanium metal or titanium platinized; and/or the voltage of the electrolytic treatment is 3.0V, and the current density is 200A/m 2 .
4. 4. The recovery treatment method according to claim 1 or 2, wherein the aluminum leaching agent is selected from a hydrochloric acid solution or an aluminum-containing hydrochloric acid solution, and the aluminum-containing hydrochloric acid solution is selected from the aluminum-containing leaching solution prepared in step (1); And/or, in the silver leaching agent, the concentration of nitric acid is 0.8-1.2 mol/L, and the concentration of hydrogen peroxide is 0.08-0.2 mol/L; and/or the silicon purifying agent is selected from hydrofluoric acid solution.
5. 5. The recovery processing method according to claim 4, wherein the concentration of the hydrochloric acid solution is 15 to 20wt%; And/or the concentration of the hydrofluoric acid solution is 4-6wt%.
6. 6. The recycling method according to claim 1 or 2, wherein the dealuminated battery powder obtained in step (1) is washed with water until the concentration of chloride ions in the washing liquid is less than 20mg/L; And/or, washing the dealuminated silver battery powder obtained in the step (2) until the concentration of silver ions in the washing liquid is less than 10 mg/L; and/or, washing with water, drying, washing with water until the pH of the washing liquid is 6-8, and drying under vacuum to obtain the silicon powder after the solid-liquid separation in the step (3).
7. 7. The recovery processing method according to claim 6, wherein the washing liquid obtained after the washing in step (1) and the washing liquid obtained after the washing in step (2) are used as the water for the washing in step (3).
8. 8. The recycling method according to claim 1 or 2, wherein the particle size of the waste photovoltaic cell powder is less than or equal to 1 mm; And/or the reaction time of the step (1) is 60-120 min; and/or the liquid-solid ratio in the reaction in the step (1) is (2.5-10) L/1 Kg.
9. 9. The recovery treatment method according to claim 1 or 2, wherein the temperature of the reaction of step (2) is 50 to 70 ℃; and/or, the reaction time of the step (2) is 60-120 min; And/or the liquid-solid ratio in the reaction in the step (2) is (2.5-10) L:1 Kg.
10. 10. The recovery processing method according to claim 1 or 2, wherein the liquid-solid ratio at the time of the reaction of step (3) is (2.5-5) L:1Kg; And/or, the reaction time of the step (3) is 60-120 min.

Description

Recovery processing method for waste photovoltaic cell Technical Field The invention relates to the technical field of photovoltaic cell recycling, in particular to a recycling method of waste photovoltaic cells. Background Along with the continuous expansion of the photovoltaic industry, the global photovoltaic module waste amount is rising year by year, and the recycling of the waste photovoltaic modules has become a key link for guaranteeing the sustainable development of the photovoltaic industry. At present, the widely applied recovery method still has various outstanding problems, most processes are only focused on the recovery of single materials such as silicon or silver, and the high-efficiency comprehensive utilization of full-component resources such as aluminum, silver and silicon cannot be realized, so that the comprehensive utilization rate of the resources is lower, meanwhile, the partial wet purification process adopts a filter screen separation mode to treat the battery piece materials, so that the loss of effective components of the battery piece is easy to occur, the overall recovery rate is lower, the links of partial technical routes are complicated, the energy consumption is higher, the structural defects of the process flow exist, in addition, the medicament consumption in the existing process is large, the medicament recycling cannot be effectively realized, the treatment cost is higher, the economical efficiency is poor, and the promotion of large-scale industrialized application is restricted. In summary, the existing waste photovoltaic cell recycling technology has obvious short plates in the aspects of comprehensive utilization of resources, optimization of technological processes, economic feasibility and the like, and is difficult to meet urgent requirements of sustainable development of the photovoltaic industry on efficient, environment-friendly and economic recycling technology. Disclosure of Invention In order to solve the technical problems, the invention provides a recovery processing method of waste photovoltaic cells, which can realize the recovery of all resources of aluminum, silver and silicon in the waste photovoltaic cells, has the advantages of environment-friendly process flow and economic feasibility, and solves the problems of low resource utilization rate, complicated flow, secondary pollution and high cost of the existing recovery method. In a first aspect, the invention provides a recovery processing method for waste photovoltaic cells, which comprises the following steps: (1) Placing the waste photovoltaic cell powder into an aluminum leaching agent for reaction, and carrying out solid-liquid separation to obtain dealuminized cell powder and aluminum-containing leaching liquid; (2) Placing the dealuminated battery powder into a silver leaching agent for reaction, carrying out solid-liquid separation to obtain dealuminated silver battery powder and silver-containing leaching liquid, and carrying out electrolytic treatment on the silver-containing leaching liquid to obtain elemental silver and electrolyte; (3) Placing the dealuminated silver battery powder into a silicon purifying agent for reaction, and carrying out solid-liquid separation to obtain silicon powder; Wherein the silver leaching agent is selected from mixed aqueous solution containing 0.8-1.5 mol/L nitric acid and 0.05-0.15 mol/L hydrogen peroxide. It is understood that the waste photovoltaic cell powder is obtained by crushing waste photovoltaic cells. Wherein the concentration of the nitric acid is 0.8-1.5 mol/L, which can be 0.8 mol/L, 1 mol/L, 1.2 mol/L, 1.4 mol/L, 1.5 mol/L and the like, and the concentration of the hydrogen peroxide is 0.05-0.15 mol/L, which can be 0.05 mol/L, 0.08 mol/L, 0.1 mol/L, 0.12 mol/L, 0.15 mol/L and the like. The recovery treatment method provided by the invention can realize the full resource recovery of aluminum, silver and silicon in the waste photovoltaic cell, the purities of elemental silver and silicon powder can reach more than 99.99%, the process flow is green and environment-friendly, the recycling of the medicament is realized, the cost is effectively reduced, the economic feasibility is realized, and the problems of low resource utilization rate, complicated flow, secondary pollution and high cost of the existing recovery method are solved. As a preferable technical scheme of the invention, the method further comprises the step of adding nitric acid into the electrolyte to obtain regenerated silver leaching agent, and recycling the regenerated silver leaching agent in the step (2). The invention utilizes the obtained electrolyte to regenerate the silver leaching agent to realize the recycling of the medicament, thereby effectively reducing the cost. The invention adopts an integrated continuous flow design, fully covers valuable resources in the battery piece, and realizes the remarkable improvement of the comprehensive utilization rate of the resour