The technology of pressure swing adsorption separation and purification (PSA) for exhaust gas treatment utilizes the differences in adsorption characteristics of gas components on solid adsorbent materials to achieve gas separation and purification through periodic pressure changes. PSA technology is a physical adsorption method that generally uses zeolite molecular sieves as adsorbents (with large adsorption capacity and strong adsorption selectivity). Under normal temperature and certain pressure conditions, organic waste gas can be adsorbed on zeolite molecular sieves, and the gas that is not adsorbed enters the next section. After adsorbing organic waste gas, the adsorbent is regenerated by depressurizing and vacuuming to desorb organic matter. The regenerated adsorbent re adsorbs organic matter in the exhaust gas, and this cycle repeats. PSA technology is a newly emerging gas separation technology in industry in recent decades, which has the advantages of low energy consumption, low investment, simple process, high degree of automation, high product purity, and no environmental pollution. It is an ideal method for various gas separation and recovery, and is highly competitive in the market.
Ozone decomposition method:
There have been no reports of ozone decomposition method in China, and there is also very little research on this technology abroad. Research has shown that O3 can be used to purify ground level exhaust gas, which can decompose non-volatile organic compounds, polycyclic aromatic organic compounds, aliphatic organic compounds, phenols, and insecticides in soil. At this time, ground gas is used as an O3 carrier. In addition, researchers also paid special attention to the changes in soil microbial status after O3 treatment, and the results showed a 99% reduction in bacteria and a decrease in respiratory performance. To this end, researchers use decomposition control techniques with pure O2 and unreacted O3 to reduce the impact of O3 treatment on soil ecosystems and achieve safety goals.
Electrochemical oxidation method:
Electrochemical oxidation technology is a chemical cell that uses an internal membrane and AgNO3-HNO3 solution for oxidation under conditions of 50-100 ℃ and atmospheric pressure. At the anode, VOCs odorous gases are converted into CO2 and H2O; At the cathode, nitrous acid is generated and can be recycled after treatment. The typical feature of this method is that the removal rate of VOCs odorous substances is high, reaching over 99%, but the operating cost is also high.