Past, Present and Future of Recycled Lead

The concentration of lead minerals and the ease of ore reduction have been recognized and applied by humans as early as 5,000 years ago. Ancient Egypt, ancient Greece, the Roman Empire, and ancient China have made the Eastern and Western civilizations shine together in the aspects of lead metallurgy and application, illuminating the historical process of human society. Entering modern industrial society, lead's unique performance can be fully exerted, so that its production and consumption increase greatly. By the middle of the 19th century, world lead production had risen to 100,000 tons per year. At the beginning of the 20th century, it increased to an annual output of 1 million tons. After 100 years of vicissitudes, global lead production and consumption in 2001 are expected to reach or exceed 6 million tons. At present, the consumption of lead has become the fifth-largest metal material in the world after iron, aluminum, copper and zinc.

The rapid increase in lead consumption is inseparable from its unique materialization and machining capabilities. In 1859, the French Gaston Plant discovered that lead oxide (Ph02) and metallic lead were used as positive and negative electrodes, respectively, and immersed in sulfuric acid medium to generate current and could be continuously charged and discharged. The discovery and application of this property It is of great significance to develop a huge market for the application of lead.

At present, the global consumption of lead is generally maintained at the level of 6 million tons, 70% is applied in the form of metallic lead or lead alloy, and the other 30% are lead compounds such as oxides, organic lead, lead chromate, lead sulfate, and silicon. Acid lead and lead carbonate form applications.
As far as the application structure is concerned, since the 1960s, the total number of motor vehicle operations has increased rapidly at an annual growth rate of 3.6%, and so far global vehicle ownership has reached 650 million, resulting in the use of lead-acid vehicles. The demand for lead in batteries has increased dramatically. During the same period, due to the large number of aluminum and plastic substitutes for lead cable sheathing, and because of the increased awareness of environmental protection, the world has generally become more aware of the harmful effects of lead on the human body, which has led to long-term use as a gasoline anti-explosion agent. The tetraethyl lead and lead-containing pigments have lost or are losing their market, so the prominent position of lead in battery production is even more pronounced.
According to the International Lead and Zinc Research Group (1LZSG), lead in the Western developed countries accounted for only 28% of the total battery production in 1960, and it rose to 73% in 1997. Among them, the application structure of lead in the United States is the most representative. On the one hand, the increasing awareness of environmental protection requires people to minimize lead exposure to the human body. On the other hand, the auto industry has become more reliant on lead-acid batteries and has chosen a path to gaining advantages and avoiding harm: In the United States, in 1997, it consumed 1.21 million. Tons of lead accounted for 92.3% of the battery, 0.6% of the cable, and 5.2% and 1.4% of semi-manufactured products and alloys respectively. There were no records of use of pigments and chemicals. In comparison, Japan and Europe accounted for 11.6% and 16.8% of their respective total usage. Although the application structure of lead in other countries is not as good as that of the United States, the overall trend in the world is that the share of batteries in the application structure of lead continues to increase. In 1998 and 1999, nearly 80% of the world’s lead consumption was used in batteries, and about 7 % is used for lead pipes and cable sheathing, with lead alloys and lead chemicals each accounting for 5%, and military ammunition for about 2%.
For thousands of years, the ever-increasing human demand for lead has left lead mineral resources on the verge of depletion. At present, the global industrial reserves of lead have fallen to 64 million tons. According to the world's annual mining rate of 3 million tons (including lead), it is only enough for mining for 21 years. At present, in respect of the demand for lead, three major consumptions (1999 figures) in Europe (2 million tons), North America (1.91 million tons), and Asia (181 million tons) were formed, resulting in the production of minerals ((primary) lead. With the serious imbalance of metal lead consumption, it is predicted that world production of lead from minerals will increase from 3.25 million tons to 330 tons from 2000 to 2004, and the actual consumption of lead metal in the world in 1999 was actually 6.21 million tons. The production has no power to lift the entire sky of lead consumption.
At present, in order to resolve a serious shortage of resources, it is also necessary to reduce the cost of raw materials and smelting, and to meet the growth of demand, and have to rely more and more on the secondary resources of lead, lead and lead. Battery grids, electrode pastes (lead paste), oxide scales, Bahrain bearing alloys, and cable jackets are the main sources of waste miscellaneous lead. Among them, used lead-acid batteries have become the main secondary source of lead.
The advantages of recovering lead using lead-acid lead-acid batteries are: reducing the consumption of mineral resources and energy consumption (the production energy of recycled lead is only 36% of the original lead); it reduces the harm to the environment and the human body from mining and smelting, eliminating the The use of lead's excellent regenerative capacity, combined with battery production, can reduce plant investment to less than half that of the original lead production plant, making it more feasible and competitive.
In the past 25 years, secondary sources of lead have been continuously accumulating. The urgent demand for lead-acid batteries in the automotive market and the actual demand for environmental governance have promoted the recovery of lead, resulting in the gradual improvement of the recycling process and the development of the recycled lead industry. The lead industry has undergone a fundamental reversal, and the production composition of recycled lead and primary lead has changed from the secondary status of recycled lead to recycled lead (47%) and primary lead accounts for half of the total. In the crude lead production of the western developed countries in 1995, recycled lead had risen to nearly 60%, occupying a dominant position, and recycled lead has become the mainstream product of the United States and Europe.
The United States has a vehicle population of 170 million vehicles, which requires an average of 1 kVAh of electricity per vehicle, while each kVAh requires 10 kg of lead (13-15 kg in the world's advanced level and 20-22 kg in China). A total of about 1.7 million tons of lead was consumed. Huge demand has created a huge renewable lead industry. The trend of mergers and acquisitions has prevailed in the United States in recent years. By 1999, although the number of factories producing lead in the United States had been reduced to only 28, the production capacity has reached 1.25 million tons, and the output has exceeded 1 million tons (1997 1.08 million tons), with a capacity of 8 There are 11 factories with 10,000-10,000 tons.
U.S. manufacturers, in addition to relying on mergers to achieve large-scale production to reduce production costs, the use of physical enrichment, hydrometallurgy and pyrometallurgical processes combined to achieve economic and environmental benefits. They used the screening machine and floatation method to further improve the efficiency of separation and enrichment of sulfur-rich paste, and leaching through soda ash to convert the paste to carbonate and to remove sulfur in the form of sodium sulfate. The sulfur content in the paste Decreased to less than 0.5%, greatly reducing the S02 emissions in reverberatory and blast furnace smelting. Some manufacturers can convert S02 produced in the smelting process into ammonium sulfite liquid fertilizer, and manufacturers use solvent extraction to purify the sulfuric acid in the waste battery so that it can be used in new batteries.
China did not form an independent professional lead recycling enterprise until 1978. However, the scale of production was small and production was dispersive. In 1990, the total output of recycled lead nationwide was only 2.82 tons. In 1994, due to the development of the automobile transportation industry, the recycled lead industry stepped into a new era of take-off, with an annual output of 95,000 tons. After that, the annual output was more than 100,000 tons. In 1997, the output was 12.37 tons, which was 4.4 times that of 1990. During this period, the output in 1995 was the highest, reaching 175,000 tons, accounting for the total output of refined lead. For 28.8%, if net export figures of 157,800 tons were excluded, the share of recycled lead in domestic net refined lead in 1995 was as high as 38.95%, but still about 47% of the world's average There is not a small gap.
The reason for this disparity is that China's primary lead (mineral lead) industry has achieved rapid development in recent years, opening the gap with recycled lead. The investment and scale of lead smelting are not large, and mines with resources can operate their own lead smelters, leading to the rise of the local primary lead industry.
In recent years, China has emerged as a large-scale recycled lead company represented by Jiangsu Chunxing Alloy (Group) Co., Ltd., Hubei Jinyang Metallurgy Co., Ltd., and Shanghai Flywheel Non-Ferrous Metals Industrial Corporation. This is a good start. However, there are many small factories, and there are generally serious problems such as small scale, backward technology, inefficient resources, energy, and environmental protection measures, affecting the healthy and sustainable development of China’s lead recycling industry. With the development of China's automobile manufacturing industry and road transport, the production of lead-acid batteries and the corresponding accumulation and disposal of used batteries will increase at the same time. The result will inevitably push China's renewable lead industry to take new steps. On the other hand, from the perspective of guaranteeing China's (raw) lead exports, it is also extremely important to actively develop the production of recycled lead. At the beginning of the new century, the production of recycled lead must take a high starting point, scale of operation, and standardization. As the enterprise itself, it is necessary to increase technological innovation, adopt new technologies, and new processes to completely change the backward appearance of China’s reclaimed lead industry. At the same time, a nationwide and comprehensive recovery network and system and authoritative recycling industry should be established. The management agencies, through strict enforcement of laws and regulations, have eliminated and lagged behind, so that the recycled lead industry in China will continue to adapt to the needs of the automobile manufacturing and other sectors, so that this harm-making industry will achieve healthy and sustainable development.