Method for heavy metal pollution control

With the rapid development of global economics, heavy metal-containing pollutants enter the soil through various channels, causing serious soil pollution. Heavy metal pollution in the soil can affect the decline of crop yield and quality, and can harm human health through the food chain, and can also lead to further deterioration of the quality of the atmosphere and water environment. Therefore, it has attracted extensive attention from all countries in the world. At present, there are different levels of heavy metal pollution in the soils of the world. The average annual emission of Hg is about 15,000 tons, Cu is 3.4 million tons, Pb is 5 million tons, Mn is 15 million tons, and Ni is 1 million tons. There are also different levels of heavy metal pollution in vegetable bases and some commodity grain bases in large cities in northern China, such as Beijing, Tianjin, Xi'an, Shenyang, Jinan, Changchun and Zhengzhou.

Regarding the study of heavy metal pollutants in soil, foreign countries began in the 1960s and 1970s. For example, Australia, the United States, Germany and other countries have deeper soil heavy metals, especially Australia. In 1983, China conducted preliminary research on the main types of soil environmental capacity, such as the study of the ecological effects of soil heavy metals, the critical content of zonal differentiation and zoning.

At present, countries all over the world attach great importance to the research on heavy metal pollution control methods and carry out extensive research work. In general, there are currently four general governance measures. Engineering governance refers to the use of physical or physical chemistry principles to control soil heavy metal pollution.

There are:

1. Chemical treatment method: chemically solidified and added with heavy metal stabilizer; the formed solidified substance can also inhibit the re-dissolution and diffusion of pollutants under the condition of changing environmental conditions (such as pH). Ultimately, the purpose of reducing heavy metal pollution is achieved.

2. Engineering treatment method: the guest soil is to add uncontaminated new soil to the polluted soil; the soil will be removed from the contaminated soil and replaced with uncontaminated new soil; the soil is turned to the lower layer; Going to the topsoil is to remove the contaminated topsoil.

3. Bioremediation methods: Use certain habits of living things to adapt, inhibit and improve heavy metal pollution. Animal management is the use of certain lower animals such as earthworms and rodents in the soil to absorb heavy metals in the soil; microbial treatment is the use of certain microorganisms in the soil to absorb, precipitate, oxidize and reduce heavy metals.

4. Agricultural management methods: controlling soil moisture refers to regulating the oxidation-reduction potential (Eh) by controlling soil moisture to reduce the pollution of heavy metals;

Ø Chemical treatment method : Kechuang heavy metal doctors use high-tech products to create heavy metal stabilizers, which can effectively stabilize and cure the soil to reduce the lead content in the environment. Kechuang Heavy Metal Stabilizer is made up of a variety of natural rock intermediates in nature and added with additives to provide natural activity and adsorption. The mechanism of the technology is to imitate the formation process of metal ore, so that the heavy metal particles are fixed by the stabilizer under the action of adsorption, reaction adsorption and ion exchange of natural rock intermediates, and further pass the water-containing amorphous substance such as silicic acid or aluminum. And the high degree of crystallization of low crystalline minerals makes heavy metals a trace component in minerals. The resulting crystalline material can form a strong structure of the solidified network through the recrystallization process and the formation of interlaced crystals between the particles, and the solidified heavy metal is further sealed in the solidified network. This process not only achieves the effect of solidification, but also achieves a stabilizing effect through the irreversible reaction process of crystal interlacing and recrystallization. The formed solidified substance can also inhibit the re-dissolution and diffusion of the contaminant when the environmental conditions change (such as pH). Ultimately, the purpose of reducing heavy metal pollution is achieved. Higher in governance costs.

Schematic diagram of heavy metal stabilizer:

Ø Engineering treatment method : 20 cm of soil is added after removing the topsoil (added as contaminated new soil). In addition, the leaching method is to wash the contaminated soil with eluent; the heat treatment method is to heat the contaminated soil and make it in the soil. Volatile contaminants (Hg) are volatilized and collected for recovery or treatment; electrolysis is the removal of heavy metals from the soil at the anode or cathode by electrolysis, electromigration, electroosmosis and electrophoresis. The above measures have the advantages of thorough and stable effects, but the implementation is complicated, the treatment cost is high, and the soil fertility is easily reduced.

Ø Biological management methods : Biological management refers to the use of certain habits of organisms to adapt, inhibit and improve heavy metal pollution. Mainly: animal management is the use of certain lower animals such as earthworms, rodents, etc. to absorb heavy metals in the soil; microbial treatment is the use of certain microorganisms in the soil to absorb, precipitate, oxidize and reduce heavy metals. Reduce the toxicity of heavy metals in the soil. The advantages of bioremediation measures are that they are simple to implement, have less investment, and have less damage to the environment. The disadvantage is that the effect of treatment is not significant.

Ø Agricultural governance methods

Agricultural governance is to adapt some farming management systems to reduce the hazards of heavy metals, and to plant plants that do not enter the food chain on contaminated soil. Reasonable use of agro-ecosystem engineering measures can also maintain soil fertility, improve and control soil heavy metal pollution, improve soil quality, and coordinate with natural ecological cycles and systems. Planting turf or cash crops (such as castor) as much as possible on both sides of the contaminated roads, planting turf or ornamental trees, transplanting and breeding, can not only beautify the environment, but also purify the soil.

At present, the domestic heavy metal pollution control company removes heavy metal water pollution control companies, and there are very few real soil and industrial pollution control companies. Facing China's economic and social development, the acceleration of industrialization, and the historical development problems accumulated by past developments and legacy, The growing pollution of heavy metals is related to the physical and mental health of the people. Pollution control is a major issue that people attach great importance to.

To this end, Beijing Keyi Innovation Environmental Technology Co., Ltd. (referred to as heavy metal doctor), and domestic and foreign well-known universities and research institutes, Chinese Academy of Sciences Ecological Environment Research Center, Peking University, Huazhong University of Science and Technology, Dalian University of Technology, and the University of Tokyo, Waseda University, Asia The University and the Hong Kong University of Science and Technology jointly launched a solution to solve the problem of heavy metal pollution in the world and realize the recycling of heavy metal resources. Heavy metal doctors are widely used in soil remediation, sludge recycling, industrial waste, tailings slag and dust & fly ash, reducing their heavy metal content, allowing pollutants to reach standards and helping enterprises solve problems. Reduce the harm caused by heavy metal pollution.

At present, the problem of soil quality in China is a strategic issue of sustainable economic development and overall social progress. It directly affects soil quality, crop growth, agricultural yield, quality of agricultural products, etc., and causes harm to human health through the food chain. Pollution control methods and techniques are more necessary and urgent.

Summary: Combining the above four methods for heavy metal pollution control, it is recommended to use the stable solidification method (heavy metal stabilizer) to control the heavy metal pollution in the soil. The high price of governance is not the key to the problem; the key is to control heavy metal pollution. There will be no secondary pollution problems. For specific governance processes, you can consult a heavy metal doctor to understand the tailored heavy metal pollution control program.