Smelting method of lead paste of lead acid storage battery

Abstract

The invention relates to a smelting method of a lead paste of a waste lead acid storage battery. The smelting method sequentially comprises the following steps of treatment of raw materials: firstly,crushing, sorting, pressing and filtering the waste lead acid storage battery, so as to obtain the lead paste; preparing: uniformly mixing the lead paste and a carbon reductant according to a mass ratio of 1:(0.06 to 0.063), so as to obtain a mixture; reaction and smelting: feeding the mixture into a rotary kiln, and quickly heating until the material is melted; adjusting the flow rate of naturalgas, maintaining the smelting temperature at 850 to 950 DEG C, controlling the flow rate ratio of oxygen to natural gas to (1.8 to 2.3):1, smelting for 3 to 4h, and reaching the reaction terminal; precipitating and smelting: adding an iron reductant into the rotary kiln, reducing the flow rate of natural gas, and utilizing the self reaction heat to perform precipitating reaction at the semi-smelting condition of 850 to 950 DEG C until the reaction terminal is reached, wherein the ratio of the iron reductant to the mixed material is 5 to 7%; lead discharging and slag discharging: (1) performingprimary lead discharging, and forming an angle of 90 degrees between a lead outlet and the ground in the lead discharging process; (2) increasing the temperature in the rotary kiln, overheating the furnace slag to the temperature above smelting point, and performing secondary lead discharging; (3) discharging the slag.

Description

technical field [0001] The invention relates to the technical field of smelting, in particular to a method for smelting waste lead-acid storage battery lead paste. Background technique [0002] Lead is one of the metals commonly used by humans. At present, lead is mainly used in lead-acid batteries. According to incomplete statistics, about 80% of the lead consumed in the world is used in lead-acid batteries. With the development of the communication and transportation industry, the demand for lead batteries will continue to grow in the near future. However, according to the current reserve-production ratio of lead mines, lead resources are increasingly depleted, and the service life of lead-acid batteries is only 2 to 4 years. , a huge amount of waste is scrapped every year. Waste lead-acid batteries contain chemical components such as lead, antimony, tin and sulfuric acid. If they are not treated and recycled, it will not only cause serious pollution to the ecological envi...

AI Technical Summary

Problems solved by technology

In the first method, because the smelting temperature reaches 1000-1100°C, the lead volatilization loss is large, and the energy consumption is 10-15% higher than other methods. In the second method, since the sulfuric acid content in the lead paste reaches more than 50%, to ensure the completion of the reaction, it is necessary to add A large amount of soda ash and iron reducing agent, the smelting temperature is not high, but the amount of smelting slag reaches 30-40%, the loss of slag lead is 15-20% more than other methods, the smelting efficiency is 20% lower than other methods, and it is difficult to solve the problem of alkalinity The corrosion of refractory materials by flux is a serious problem. As the price of refractory materials continues to rise, the life of the furnace directly affects the smelting cost.