Lithium material extraction technology and industrialization progress -Lithium - Ion Battery Equipment
Global lithium resources are widely distributed, but reserves are limited. At present, they are mainly concentrated in South America, my country, and some places in Africa. my country's lithium resources are concentrated in salt lakes and ores. About 70% of the currently proven reserves are concentrated in the salt lakes of Qinghai, and some are scattered in mines. Due to their different natural endowments, these two resources have differences in later mining, extraction, production technology and product quality.
As far as domestic salt lake resources are concerned, they are mainly distributed in five provinces in the west. However, salt lakes with lithium resources are only concentrated in the Qinghai-Tibet Plateau, and more of them are concentrated in Qinghai. No industry is allowed to be built in Tibet. Therefore, in 2013, Qinghai and Tibet established the Tibetan-Qinghai Industrial Park in Golmud City, Qinghai through central coordination. Therefore, Tibet’s industrial system focusing on resource development is now in Qinghai, which means that it can now and in the future The industries established to extract and develop salt lake lithium resources are all concentrated in Qinghai.(Lithium - Ion Battery Equipment)
According to some data released by the U.S. Bureau of Geological Survey, lithium resource reserves have new survey data every year, and they have still changed in the past two years. These data have yet to be verified. According to verified and published data in 2013, my country's total lithium resource reserves account for about 20% of the global total.
The world's lithium resources are mainly concentrated in salt lakes. From the current point of view, the foundation of technology development and production construction is focused on the development and effective utilization of salt lake resources, because the damage to the environment caused by the development of salt lake resources is currently minimal, and The development and mining of mines damages the environment extremely seriously. We can analyze the situation of salt lakes at home and abroad. In terms of the composition of some foreign salt lakes, the content of some salt lakes is higher. For example, the content of Alcatama is about 0.15 grams per liter. In other places, it is only tens to hundreds of ppm. The range is as low as a few ppm. Among them, the ones with the largest reserves or the best quality are still in the process of development. The ones currently most developed are Uyuni in Bolivia and Ricon in Argentina.
At present, all the salt lakes that can be developed in our country are concentrated in Qinghai. One of the very important large-scale lithium-containing salt lake areas in Qinghai is the Qarhan Salt Lake area, and the others are Dongtai, Xitai and Yiliping. From the perspective of mineral endowment, we particularly emphasize the magnesium-lithium ratio issue in the salt chemical industry, which greatly increases the difficulty and cost.
In August this year, General Secretary Xi Jinping visited Qinghai and gave special instructions on the comprehensive development and utilization of salt lake resources, the most important of which are potassium and lithium. Issues related to lithium directly involve our country's dependence on foreign countries, and also involve what we have been developing domestically, such as the fourth-generation nuclear energy system being developed by the Chinese Academy of Sciences, which uses some high-purity lithium-7 raw materials , all must be obtained from salt lake resources, so we have put the development of salt lake resources and the extraction of lithium on the important agenda.
Current status of domestic salt lake lithium resource development
At present, both the extraction of lithium from ores and the extraction of lithium from salt lakes fall into five aspects: adsorption method, roasting method, extraction method, precipitation method, and electrodialysis method. These five methods are all used in the development of salt lake resources. Four of them are concentrated in the salt lakes of Qinghai, among which the sedimentation method is used in the Zabuye Salt Lake in Tibet.
Electrodialysis uses a membrane and an electric field to drive the smallest ions through the membrane, and the rest flow to the other side of the membrane. Among them, effectively eliminating magnesium ions through precipitation and electric fields is a technical difficulty, so solving this problem is the core of electrodialysis. Since magnesium needs to be isolated to achieve adsorption and bonding effects of magnesium ions on the membrane, the entire production cost and production cycle have been affected.
Extraction methods have developed rapidly in the past year or two. When my country began preparing to develop its first hydrogen bomb in the late 1950s, it proposed using extraction methods to first extract high-purity lithium chloride and then purify lithium isotopes. However, because the equipment, materials, extraction agents and other aspects at that time did not reach the ideal state, it was never realized. After decades of progress, this method has been promoted in an all-round way in the past two years. The core issue is to meet the requirements of the extraction method through newly developed extraction agents and current advances in extraction machines and corrosion-resistant materials. Through extraction and stripping, high-purity lithium chloride is first obtained, and then carbonized to finally obtain lithium carbonate. In fact, this method and technology are very different from other technologies. In the process of gradual use of battery materials, the demand is not only limited to lithium carbonate, but also to lithium hydroxide and even lithium chloride in the future. All can be gradually used as materials. Therefore, this method can prepare a variety of raw materials, and the purity can fully meet the current demand for the highest level of battery-grade lithium carbonate.
From the basic principles of chemistry, the most conventional or simplest method is precipitation. There are two problems with the precipitation method. One is through concentration and crystallization, and the other is through carbonization. The purity of the product is poorer. Of course, subsequent purification and processing by some auxiliary manufacturers or secondary manufacturers can still meet the needs of battery materials. needs.
The current technical difficulty that has not been completely broken through is the adsorption method. Due to its adsorption characteristics, it is currently mainly used in some salt lakes with the lowest lithium concentration, such as Qarhan Salt Lake. Its magnesium-lithium ratio is as high as 1800 times. In the original brine The lithium ion concentration is only about 30 ppm. Using the adsorption method to extract lithium carbonate, a total of about 1,500 tons was produced by the end of last year, which is the largest production capacity of the adsorption method in the world.
The roasting method is carried out by the company CITIC Guoan. There is no problem with this process in terms of chemical principles, but serious environmental pollution problems arise in actual production. This technology is currently being produced in Qinghai with only one line, with an output of about 10,000 tons. , the actual production volume should not exceed 3,000 tons.
Judging from the current domestic production situation, the advantages and disadvantages of extracting lithium from the ore method and extracting lithium from salt lake resources are very different. Especially under the clear requirements for environmental protection, the pressure for the future survival of the ore method will be very huge. On the one hand, its production cost is high and raw materials need to be imported in large quantities. On the other hand, the environmental pollution is serious. In the ore process, due to the high temperature, combined operation of fire method and wet method, the emissions of gas, liquid and solid waste are relatively serious. Using salt lake resources to extract lithium, the cost of several existing processes is lower than the cost of extracting lithium from ore. At the same time, the five methods just mentioned are different, and no one has announced the exact number. The production cost is in the range of 10,000-20,000. From an environmental point of view, because lithium is extracted in saline-alkali or salt lake areas that are deserted and barren of tens of thousands of square kilometers, if the old brine after lithium extraction is stored or discharged to another fixed location, it will be harmful to the environment. It is said that there is no direct impact, there is no air pollution or solid waste pollution. The stacking of old brine is just to extract the lithium and potassium in it and then store it in another place. What may affect the future groundwater. Therefore, from an environmental perspective, lithium extraction from salt lake resources is much superior to the ore method.
The rising trend of lithium salt products
We have made a lot of statistics on the consumption of lithium salt products. Among them, battery demand accounts for about 50% of the total demand, and the fastest growing demand is also for batteries.
At present, from the beginning of raw materials to the subsequent processing of various processes, the technology has gradually been improved, forming a series of products, and further development will be carried out in response to product needs. The development of salt lake resources has also established a series of complete R&D systems and product systems.
Qinghai has made it clear that it will build a 100 billion yuan lithium battery materials industry and a 100 billion yuan lithium industry in the "13th Five-Year Plan". The development goal of the lithium salt industry in the "13th Five-Year Plan" is to achieve an output of 200,000 tons of lithium carbonate and lithium chloride. 30,000 tons, 10,000 tons of lithium hydroxide, and 10,000 tons of metallic lithium. The first three are related to lithium batteries, and new materials such as metallic lithium may also be used in lithium batteries in the future.
As far as domestic salt lake resources are concerned, they are mainly distributed in five provinces in the west. However, salt lakes with lithium resources are only concentrated in the Qinghai-Tibet Plateau, and more of them are concentrated in Qinghai. No industry is allowed to be built in Tibet. Therefore, in 2013, Qinghai and Tibet established the Tibetan-Qinghai Industrial Park in Golmud City, Qinghai through central coordination. Therefore, Tibet’s industrial system focusing on resource development is now in Qinghai, which means that it can now and in the future The industries established to extract and develop salt lake lithium resources are all concentrated in Qinghai.(Lithium - Ion Battery Equipment)
According to some data released by the U.S. Bureau of Geological Survey, lithium resource reserves have new survey data every year, and they have still changed in the past two years. These data have yet to be verified. According to verified and published data in 2013, my country's total lithium resource reserves account for about 20% of the global total.
The world's lithium resources are mainly concentrated in salt lakes. From the current point of view, the foundation of technology development and production construction is focused on the development and effective utilization of salt lake resources, because the damage to the environment caused by the development of salt lake resources is currently minimal, and The development and mining of mines damages the environment extremely seriously. We can analyze the situation of salt lakes at home and abroad. In terms of the composition of some foreign salt lakes, the content of some salt lakes is higher. For example, the content of Alcatama is about 0.15 grams per liter. In other places, it is only tens to hundreds of ppm. The range is as low as a few ppm. Among them, the ones with the largest reserves or the best quality are still in the process of development. The ones currently most developed are Uyuni in Bolivia and Ricon in Argentina.
At present, all the salt lakes that can be developed in our country are concentrated in Qinghai. One of the very important large-scale lithium-containing salt lake areas in Qinghai is the Qarhan Salt Lake area, and the others are Dongtai, Xitai and Yiliping. From the perspective of mineral endowment, we particularly emphasize the magnesium-lithium ratio issue in the salt chemical industry, which greatly increases the difficulty and cost.
In August this year, General Secretary Xi Jinping visited Qinghai and gave special instructions on the comprehensive development and utilization of salt lake resources, the most important of which are potassium and lithium. Issues related to lithium directly involve our country's dependence on foreign countries, and also involve what we have been developing domestically, such as the fourth-generation nuclear energy system being developed by the Chinese Academy of Sciences, which uses some high-purity lithium-7 raw materials , all must be obtained from salt lake resources, so we have put the development of salt lake resources and the extraction of lithium on the important agenda.
Current status of domestic salt lake lithium resource development
At present, both the extraction of lithium from ores and the extraction of lithium from salt lakes fall into five aspects: adsorption method, roasting method, extraction method, precipitation method, and electrodialysis method. These five methods are all used in the development of salt lake resources. Four of them are concentrated in the salt lakes of Qinghai, among which the sedimentation method is used in the Zabuye Salt Lake in Tibet.
Electrodialysis uses a membrane and an electric field to drive the smallest ions through the membrane, and the rest flow to the other side of the membrane. Among them, effectively eliminating magnesium ions through precipitation and electric fields is a technical difficulty, so solving this problem is the core of electrodialysis. Since magnesium needs to be isolated to achieve adsorption and bonding effects of magnesium ions on the membrane, the entire production cost and production cycle have been affected.
Extraction methods have developed rapidly in the past year or two. When my country began preparing to develop its first hydrogen bomb in the late 1950s, it proposed using extraction methods to first extract high-purity lithium chloride and then purify lithium isotopes. However, because the equipment, materials, extraction agents and other aspects at that time did not reach the ideal state, it was never realized. After decades of progress, this method has been promoted in an all-round way in the past two years. The core issue is to meet the requirements of the extraction method through newly developed extraction agents and current advances in extraction machines and corrosion-resistant materials. Through extraction and stripping, high-purity lithium chloride is first obtained, and then carbonized to finally obtain lithium carbonate. In fact, this method and technology are very different from other technologies. In the process of gradual use of battery materials, the demand is not only limited to lithium carbonate, but also to lithium hydroxide and even lithium chloride in the future. All can be gradually used as materials. Therefore, this method can prepare a variety of raw materials, and the purity can fully meet the current demand for the highest level of battery-grade lithium carbonate.
From the basic principles of chemistry, the most conventional or simplest method is precipitation. There are two problems with the precipitation method. One is through concentration and crystallization, and the other is through carbonization. The purity of the product is poorer. Of course, subsequent purification and processing by some auxiliary manufacturers or secondary manufacturers can still meet the needs of battery materials. needs.
The current technical difficulty that has not been completely broken through is the adsorption method. Due to its adsorption characteristics, it is currently mainly used in some salt lakes with the lowest lithium concentration, such as Qarhan Salt Lake. Its magnesium-lithium ratio is as high as 1800 times. In the original brine The lithium ion concentration is only about 30 ppm. Using the adsorption method to extract lithium carbonate, a total of about 1,500 tons was produced by the end of last year, which is the largest production capacity of the adsorption method in the world.
The roasting method is carried out by the company CITIC Guoan. There is no problem with this process in terms of chemical principles, but serious environmental pollution problems arise in actual production. This technology is currently being produced in Qinghai with only one line, with an output of about 10,000 tons. , the actual production volume should not exceed 3,000 tons.
Judging from the current domestic production situation, the advantages and disadvantages of extracting lithium from the ore method and extracting lithium from salt lake resources are very different. Especially under the clear requirements for environmental protection, the pressure for the future survival of the ore method will be very huge. On the one hand, its production cost is high and raw materials need to be imported in large quantities. On the other hand, the environmental pollution is serious. In the ore process, due to the high temperature, combined operation of fire method and wet method, the emissions of gas, liquid and solid waste are relatively serious. Using salt lake resources to extract lithium, the cost of several existing processes is lower than the cost of extracting lithium from ore. At the same time, the five methods just mentioned are different, and no one has announced the exact number. The production cost is in the range of 10,000-20,000. From an environmental point of view, because lithium is extracted in saline-alkali or salt lake areas that are deserted and barren of tens of thousands of square kilometers, if the old brine after lithium extraction is stored or discharged to another fixed location, it will be harmful to the environment. It is said that there is no direct impact, there is no air pollution or solid waste pollution. The stacking of old brine is just to extract the lithium and potassium in it and then store it in another place. What may affect the future groundwater. Therefore, from an environmental perspective, lithium extraction from salt lake resources is much superior to the ore method.
The rising trend of lithium salt products
We have made a lot of statistics on the consumption of lithium salt products. Among them, battery demand accounts for about 50% of the total demand, and the fastest growing demand is also for batteries.
At present, from the beginning of raw materials to the subsequent processing of various processes, the technology has gradually been improved, forming a series of products, and further development will be carried out in response to product needs. The development of salt lake resources has also established a series of complete R&D systems and product systems.
Qinghai has made it clear that it will build a 100 billion yuan lithium battery materials industry and a 100 billion yuan lithium industry in the "13th Five-Year Plan". The development goal of the lithium salt industry in the "13th Five-Year Plan" is to achieve an output of 200,000 tons of lithium carbonate and lithium chloride. 30,000 tons, 10,000 tons of lithium hydroxide, and 10,000 tons of metallic lithium. The first three are related to lithium batteries, and new materials such as metallic lithium may also be used in lithium batteries in the future.
