With the continuous development of social economy and the continuous rise of industry, air pollution is becoming more and more serious, which poses a serious threat to air pollution and human health. Research shows that industrial waste gas contains organic compounds, sulfides, fluorides and other chemical substances, which seriously endanger human health and greatly increase the incidence rate of respiratory tract related cancer. Benzene organics damage human central nerve and cause nervous system disorders; Polycyclic aromatic compounds have strong carcinogenicity. The gas containing conjugates enters the human body, which mainly damages the central nervous system and respiratory system, stimulates the point membrane to absorb the gas of conjugates for a long time, resulting in brain function damage and affecting cell metabolism and protein synthesis.
With the continuous development of social economy, the country has higher and higher requirements for environmental protection, and people's awareness of environmental protection is gradually strengthened. The quality requirements for the environment have become higher. In the future, the control and degradation of air pollutants will inevitably be one of the main research directions of environmental materials in the future. Next, I'll sort out several waste gas treatment processes for you.
There are many kinds of exhaust pollutants from internal combustion engines with different characteristics. Select appropriate treatment methods for different types of internal combustion engine exhaust gases. Common tail gas treatment methods include:
1) Doc diesel exhaust catalytic oxidizer
Remove CO, HC and a small amount of C particles, oxidize no in the exhaust gas to NO2, and remove CO and HC in the exhaust gas at the same time.
2) The CDPF diesel engine exhaust catalytic oxidation particulate trap will capture carbon particles and react with NO2 to form CO2 at low temperature for elimination. The no generated by the reaction of NO2 with carbon particles is oxidized to NO2 again, and continues to react with carbon particles to achieve sustainable utilization. At the same time, CDPF can also remove CD and HC that doc does not react completely.
3) DPF diesel engine exhaust particulate trap is a black smoke purification equipment that can remove black smoke and PM particles from diesel engine exhaust.
It adopts metal felt filter material made of 316L alloy wire imported from France. According to the characteristics of internal combustion engine exhaust, DPF filter carrier with modular and customized design and professional hydrodynamics design (exhaust gas can pass through the filter element 360 degrees) is adopted. The particle capture cross-sectional area is large, the initial back pressure is small, and the back pressure rises slowly. The unit can be easily disassembled, can be flexibly extracted and washed for regeneration, has convenient and fast maintenance, long service life, and has 10-15 DB noise reduction function at the same time. The black smoke treatment efficiency is 90% - 98%. It is also equipped with a safety bypass, which can be automatically opened when the blockage causes a high back pressure alarm to ensure safe use.
4) Orc redox catalyst
Remove NOx, Co, HC, C particles
5) Selective reduction (SCR) - the gas formed by the oxidation of nitrogen in the cylinder at high temperature (mainly composed of nitric oxide and nitrogen dioxide) controls NOx in the generator tail gas. NH3 or urea (usually 32.5% urea aqueous solution by mass ratio) is used as the reducing agent. Under the action of a certain temperature and catalyst, NH3 is used to reduce NOx to N2 and H2O. Because NH3 selectively reduces NOx first, Without reacting with O2 first. It is applicable to NOx control of diesel engine exhaust, NOx control of internal combustion engine exhaust, denitration of boilers, denitration of power plants, industrial furnaces and incinerators.
6) ASC: ammonia escape catalyst. An exhaust after treatment device of internal combustion engine, which is installed at the rear end of SCR and reduces ammonia (NH3) leaked from the exhaust at the rear end of SCR through catalytic oxidation.