What are the main global air pollution problems? How can the discipline of chemistry play a role in combating atmospheric pollution?

Because of the mobility and wholeness of the atmosphere, atmospheric pollution is often characterized by a global nature, caused by these pollutants global acid rain problem, the greenhouse effect problem, the destruction of the ozone layer has become the world's countries are particularly concerned about three major problems. Global atmospheric pollution directly damages the Earth's life support system.

1, control coal pollution. The use of raw coal desulfurization technology can remove about 40% to 60% of the inorganic sulfur in coal combustion. Prioritize the use of low-sulfur fuels, such as low-sulfur coal and natural gas, which contain less sulfur. Improve coal combustion technologies to reduce emissions of sulphur dioxide and nitrogen oxides during coal combustion. For example, liquefied coal combustion technology is one of the new technologies welcomed by various countries.

It mainly utilizes the addition of limestone and dolomite, which reacts with sulfur dioxide to produce calcium sulfate to be discharged with the ash residue. Flue gas desulfurization is carried out on the flue gas formed after coal combustion before it is discharged into the atmosphere. Development of new energy sources, such as solar, wind, nuclear, combustible ice, etc., but the technology is not mature enough, if used will cause new pollution, and consumption costs are very high.

2, strengthen the process measures. Strengthen the process. Take non-toxic or low-toxic raw materials instead of toxic raw materials. Take closed loop to reduce the exclusion of pollutants, etc.. Strengthen production management. Prevent the occurrence of all possible emissions pollution of the atmosphere. Comprehensive utilization of waste into treasure. For example, a large amount of coal ash discharged from power plants can be made into cement, bricks and other building materials. Nitrogen can be recovered to make nitrogen fertilizer and so on.

Expanded Information

Factors affecting the extent and intensity of atmospheric pollution are the nature of the pollutants (physical and chemical), the nature of the source of pollution (source strength, source height, temperature within the source, exhaust rate, etc.), meteorological conditions (wind direction, wind speed, temperature stratification, etc.), the nature of the ground surface (terrain relief, roughness, ground cover, etc.) .

The higher the concentration of harmful substances in the atmosphere, the heavier the pollution and the greater the harm. The concentration of pollutants in the atmosphere depends on the total amount of emissions, but is also related to the height of the emission source, meteorology and topography.

As soon as a pollutant enters the atmosphere, it dilutes and spreads. The stronger the wind, the stronger the atmospheric turbulence, the more unstable the atmosphere, the faster the dilution and diffusion of pollutants; conversely, the dilution and diffusion of pollutants is slow.

In the latter case, especially in the presence of an inversion layer, pollutants can often accumulate to very high concentrations, resulting in serious air pollution events. Although precipitation can play a purifying role in the atmosphere, air pollution can be transformed into water pollution and soil pollution because pollutants land with rain and snow.

Baidu Encyclopedia - Atmospheric Pollution

Baidu Encyclopedia - Global Atmospheric Pollution