New technology of carbon neutralization

New Tech.2 of Carbon neutralization

Product description: New Tech.2 of Carbon neutralization
INQUIRY

New technology of carbon neutralization in kiln system

——CO₂ mineralization power generation of kiln exhaust gas

The contradiction between human energy demand and carbon dioxide emission reduction has become a global strategic problem in current economic development. China's carbon emissions will reach the peak in 2030. How to make rational use of energy, reduce carbon emissions and reduce the greenhouse effect has become the first problem for technical personnel in the field of energy, heat and environmental protection. Previously, geological storage was one of the strategies for large-scale treatment of carbon dioxide, but this method did not fundamentally reduce CO2 emissions. Only by effectively utilizing the physical and chemical properties of CO2, turning waste into treasure and realizing the recycling of CO2, is the fundamental solution to the problem.

For the large-scale dry rotary kiln cement production system, 0.95 tons of CO₂ will be generated for each ton of ordinary cement clinker produced due to fuel combustion, material decomposition, power consumption and other reasons. For oil well cement clinker and white cement clinker, the amount of CO₂ produced per ton of clinker will reach 1.03 tons and 1.1 tons respectively. At present, China's cement clinker production capacity is as high as 2 billion tons. Facing the annual CO₂ emission of nearly 2 billion tons, the technicians in the cement industry can not be indifferent.

The most effective methods are as follows: 1. Supercritical CO₂ waste heat generation (the United States is the leading technology in making use of CO₂ physical characteristics as the article); 2. CO₂ mineralization treatment and power generation (the paper is based on the chemical characteristics of CO₂, leading in China Technology).

Supercritical CO₂power generation takes advantage of the physical advantages of CO₂, such as low viscosity, high liquid density, good fluidity, high thermal efficiency and low compressibility, to capture CO₂ from kiln exhaust gas (CO₂ from kiln exhaust gas of cement industry is the system with the highest CO₂ concentration in all industrial systems, Because the CO₂ produced by carbonate decomposition and fuel combustion can not be achieved by any industrial system) and treated to a critical state, then it is used as a heat transfer working medium to replace the original system of steam low-temperature waste heat power generation system, and the Bruno cycle is used for efficient power generation. At present, the technology has been successfully implemented in the 10 MWh power generation system of the thermal laboratory of Massachusetts Institute of Technology, with an investment of about 16 million US dollars. Supercritical CO₂ as working medium will be used in nuclear reactor, solar energy, industrial waste heat and other fields. The production of cement industry can provide a large amount of continuous supercritical CO₂ to meet the requirements of working medium in various fields. According to the plan of the U.S. Department of energy, all thermal power generation systems in the U.S. will adopt supercritical CO₂ power generation technology in the next 10 years, which is the inevitable trend of future thermal power generation in the world.

CO₂ mineralized power generation is to use the chemical characteristics of CO₂ to convert chemical energy into electrical energy in the process of being mineralized. At present, Chinese technicians have successfully used industrial alkaline wastes such as calcium carbide slag, organic waste alkali, cement dust and steel slag as raw materials for carbon dioxide mineralization power generation to stabilize the output of electric energy. While using carbon dioxide mineralization power generation, they also produce high value-added chemical product sodium bicarbonate, and at the same time deal with industrial wastes harmful to the environment, It has formed a new way of carbon dioxide emission reduction and utilization which is environment-friendly and sustainable circular economy development. Mineralization of 1 ton of carbon dioxide can produce 140 degrees of electricity, and 1.91 tons of sodium bicarbonate worth 2000 to 3000 yuan. Obviously, only the CO₂ emitted by China's cement industry is mineralized for power generation, which is the total power generation of the Three Gorges Dam, and at the same time produces additional minerals worth 800 million yuan, with considerable benefits.

Make full use of the physical and chemical characteristics of CO₂ to turn waste into treasure. In the future large industrial production, zero carbon emission will be realized. By then, CO₂ in the atmosphere will be "not enough", and people no longer have to tangle with carbon emission and greenhouse effect. Thermal enterprises should start their voyage from this point on and start a new journey.