沼气从厌氧发酵装置产出时，特别是在中温或高温发酵时，携带有大量的H2S 。由于沼气中还有大量的水蒸汽存在，水与沼气中的H2S 共同作用，加速了金属管道、阀门和流量计的腐蚀和堵塞。
When biogas is produced from anaerobic fermentation plant, especially at medium or high temperature, it carries a large amount of H2S. Due to the existence of a large amount of water vapor in biogas, the combined action of water and H2S in biogas accelerates the corrosion and blockage of metal pipes, valves and flowmeters.
另外， H2S 燃烧后生成的SO2 ，与燃烧产物中的水蒸气结合成亚硫酸，使设备的金属表面产生腐蚀，并且还会造成对大气环境的污染，影响人体健康。因此，在使用沼气之前，必须脱除其中的H2S 。
In addition, the SO2 generated after H2S combustion combines with the water vapor in the combustion zhongyaogui.71ix.comzhenkongdai.37ix.com.cnshuitong.71ix.comdibanms.37ix.com.cn langan.37ix.com.cnbaiyangdian.37ix.com.cnproducts to form sulfite, which causes corrosion on the metal surface of the equipment, and also pollutes the atmospheric environment and affects human health. Therefore, H2S must be removed before biogas is used.