1. China's waste lead-acid recycling industry
At present, a considerable part of waste lead-acid batteries in China are dismantled and smelted in small recycling plants. The waste acid, lead paste, waste gas and waste dust produced in the process have not been properly treated, and are directly discharged into the surrounding environment, causing serious pollution. In the total circulation process of waste lead-acid batteries, the number collected by self-employed households accounts for more than 70% of the total; and among the many enterprises that generate waste lead-acid batteries, less than 5% are directly sent to professional processing plants for processing.
Due to historical reasons, there is still a considerable gap between China's secondary lead industry and other countries. At present, there are only a few large-scale, high-yield and advanced process equipment in China, high resource recovery rate, and little environmental pollution, such as Jiangsu Chunxing Group, Hubei Jinyang Group and Shanghai Feilun Group. The three large-scale waste lead-acid battery recycling enterprises have an annual output of 95,000 tons of recycled lead, accounting for more than 1/2 of China's total output. These enterprises are not only large in scale, high in output, but also in advanced process equipment, high in resource recovery and low in environmental pollution. However, due to the investment in environmental facilities, insufficient raw materials for waste lead-acid batteries, unsaturated production capacity, high production costs and high management costs, etc., it is impossible to compete with the original "local method" production enterprises in terms of cost, and the enterprise has a heavy burden.
According to incomplete statistics, at present, in my country's secondary lead smelting industry, there are about 30 enterprises with a processing capacity of more than 5,000 tons per year, and about 20 enterprises with a processing capacity of more than 10,000 tons per year; and the actual processing capacity exceeds 5,000 tons per year. There are 19 companies with more than 10,000 tons/year, and 11 companies. There are more than 300 secondary lead smelting enterprises in my country, so there are a large number of small smelting enterprises and even family-owned workshop enterprises, which waste resources and also bring serious environmental pollution.
2. Problems existing in China's waste lead-acid management and recycling industry
The following problems exist in the collection and transportation of waste lead-acid batteries.
①Because people's environmental awareness is weak and the simple dismantling and recycling of lead-acid batteries can make huge profits, regular lead recycling manufacturers must abide by certain environmental and health standards, the cost of its collection and reuse is high, and most lead-acid batteries are collected and reused illegally, and they are hardly managed as hazardous waste.
② During the collection and transportation of lead-acid batteries, most of the lead-acid batteries are collected by small vendors, sent to nearby waste recycling stations, and then transported away by manufacturers or reuse manufacturers; there are no special protective measures for waste lead-acid batteries in the middle. If an accident occurs, such as acid leakage, it is very easy to cause serious damage to the surrounding environment and human health.
③Because the lead sheet recovered by some waste collection stations has a certain price advantage over the whole waste lead-acid battery, after a small amount of waste lead-acid battery is collected, and then directly dismantled by waste buyers, and the drained lead-containing acid (sulfuric acid and sulfate) seriously pollutes the surrounding soil. At the same time, after dismantling waste plastics into the municipal waste system or recycling, because it contains metal lead and lead salts, it may also cause harm to the environment.
④According to the investigation, some companies only recycle lead ingots and miscellaneous lead, and the dismantling process is completely completed in general manual workshops. After the whole lead-acid battery is dismantled, a large amount of waste acid (sulfuric acid and lead-containing sulfate) produced for the recovery of valuable lead and other alloys is directly discharged into the sewer or the surrounding soil without treatment; the remaining waste plastics (lead-acid battery casings) are stacked in disorder, and most of them are directly burned.
⑤ Because lead recycling enterprises do not accept lead-acid batteries containing waste liquid. In fact, before the waste lead-acid battery is transported, the waste acid has been dumped out.
From the overall level of China's waste lead battery recycling lead plants, there are many enterprises engaged in lead recycling, small scale, high energy consumption, heavy pollution, backward process technology, and low metal recovery and comprehensive utilization rate. These secondary lead factories mainly use traditional smelting processes such as small reverberatory furnaces, blast furnaces and cupola furnaces. The plates and slurry are all mixed, and most of them have not undergone pretreatment processes, and 90% of the enterprises lack soot treatment facilities. At the same time, due to the backward smelting technology and equipment, all the plates and slurry are mixed, resulting in serious environmental pollution and waste of resources, mainly as follows.
①The lead recovery rate is low. The recovery rate abroad is generally 95%, while China is currently only 80% to 85%. More than 20,000 tons of lead are lost in the smelting process in China every year, which not only causes waste of resources, but more importantly, when these lead enters the environment, it will seriously endanger human health.
② The comprehensive utilization rate is low. Due to the lack of sorting and processing technology, many enterprises only mix the battery plates and slurry, and the alloy components such as antimony are not fully utilized and become waste residues.
③ High energy consumption. China's current lead recovery energy consumption is generally 2 to 4 times that of foreign countries.
④ serious pollution. In the process of lead smelting, a large amount of lead vapor, lead dust, sulfur dioxide and other pollutants will be produced, and the lead content in the exhaust gas will exceed the national standard by dozens of times. However, more than 90% of Chinese enterprises have not taken appropriate measures and facilities for smoke and dust treatment, and the overall level is only equivalent to the international development level in the 1960s.