The chemical manufacturing companies faces numerous environmental challenges, primarily in the following aspects:
- Air pollution: chemical manufacturing companies are significant sources of air pollution, with main pollutants including sulfur dioxide (SO₂), nitrogen oxides (NOₓ), volatile organic compounds (VOCs), and dust. These pollutants can not only directly harm human health but also trigger secondary pollution such as acid rain and photochemical smog. For example, in the combustion process of boilers and kilns, fossil fuels are burned, and in chemical reactions such as nitrification and oxidation, NOₓ is produced. Additionally, the unorganized emission of VOCs during material transportation and storage also contributes to air pollution.
- Water pollution: Chemical wastewater is complex in composition, highly toxic, and difficult to treat. Common pollutants include heavy metal ions (such as mercury, cadmium, and lead), organic pollutants (such as phenols, cyanides, and polycyclic aromatic hydrocarbons), and acid-base substances. The high concentration of COD/BOD, heavy metals, and continuous discharge are the main emission characteristics. Long-term discharge can lead to eutrophication of water bodies, poisoning of the biological chain, and even threaten drinking water safety.
- Soil and groundwater pollution: The improper disposal of chemical solid waste (such as waste catalysts and sludge) and leaked chemicals are the main ways to cause soil and groundwater pollution. Pollutants can enter groundwater through leaching, causing long-term and difficult-to-repair pollution. For instance, the lead and arsenic content in the soil around waste residue yards can exceed the standard by 3-10 times, and the leakage of underground storage tanks can lead to the concentration of TCE (trichloroethylene) in the surrounding groundwater exceeding the standard by 50 times.
- Noise pollution: The operation of large equipment such as compressors and pumps in chemical plants generates high-intensity noise, which affects the health of employees and the surrounding community.
- Solid waste pollution: The chemical manufacturing companies generates a large number of hazardous wastes, such as waste acids, waste alkalis, and waste organic solvents. If not disposed of properly, it will cause secondary pollution.