1. Biogas will produce hydrogen sulfide, which is highly toxic. When the concentration in the air is 14.mg/m3 (standard), it will cause conjunctival inflammation and corneal inflammation. When the concentration is about 280mg / m3 (standard), it will cause coma, dyspnea and even death.
2. Sulfur dioxide generated by hydrogen sulfide combustion will generate sulfuric acid molecules in contact with water, corrode the surrounding equipment, pollute the environment, and corrode in contact with metals, especially non-ferrous metals.
3. Desulfurization methods: according to the physical and chemical properties, the current biogas desulfurization methods can adopt physical, chemical and biological methods respectively. The direct desulfurization method of biogas desulfurization equipment can be divided into wet method and dry method according to different principles. The following focuses on wet method and dry method.
Dry desulfurization technology of biogas desulfurization equipment is a biogas desulfurization method that uses oxygen to oxidize H2S gas into elemental sulfur or sulfur oxide. Its common methods are iron oxide dry desulfurization method, activated carbon method, membrane separation method, etc. it is suitable for gases with low H2S concentration. It is widely used in industry because of its simple structure and mature desulfurization technology.
沼气脱硫设备湿法脱硫技能是利用额定的溶剂和气体逆流接触脱除硫化氢，溶剂经回生后吸收再利用的脱硫方法。其常用方法有碱性溶液吸收法、ADA法、HPAS氧化—空气回生法。适宜解决气量大、H2S 浓度高的气体 。 湿法脱硫技能工艺流程简单 、操作连续、脱硫效率高，并且可以直接获得元素硫，现也在工业上获得了一些应用。
Wet desulfurization technology of biogas desulfurization equipment is a desulfurization method that uses rated solvent and gas countercurrent contact to remove hydrogen sulfide, and the solvent is absorbed and reused after regeneration. The common methods are alkaline solution absorption method, ADA method and HPAs oxidation air regeneration method. It is suitable for solving the gas with large gas volume and high H2S} concentration. Wet desulfurization technology has the advantages of simple process flow, continuous operation, high desulfurization efficiency, and can directly obtain elemental sulfur. Now it has also been applied in industry.
With the continuous economic development and energy construction of the market, the construction of biogas project has been effectively promoted. Through the continuous research of researchers, there are more and more processes on how to remove H2S from biogas, and gradually develop a number of biogas desulfurization processes and complete sets of equipment with independent intellectual property rights with low cost, low freight, reliable and high automation level.