After anaerobic treatment in the process of resource utilization of organic waste, the biogas produced contains a variety of gases, of which CH4 is a very good clean energy, but H2S is a corrosive gas with odor, which is highly corrosive to subsequent pipelines, biogas cabinets and gas combustion equipment, and the concentration of SO2 produced after H2S combustion is very high, The pollution to the natural environment is very serious. Therefore, H2S in biogas shall be removed before biogas utilization to avoid corrosion to later equipment.

碱法生物脱硫过程分为两步：

The alkaline biological desulfurization process is divided into two steps:

一：沼气通过脱硫反应塔将沼气中H2S从气相转化成液相。脱硫反应塔就是一个洗涤塔，沼气从塔底部进入并穿过滤料床。微碱性循环水从塔顶进入，经过专用喷头打散，自由落体穿过滤床，专用滤料可以使沼气与循环水进一步打散和延长接触时间，提高洗涤效果。含有硫化物的循环水从脱硫反应塔底部流入再生池。

1： The H2S in biogas is converted from gas phase to liquid phase through desulfurization reactor. The desulfurization reaction tower is a scrubber, and the biogas enters from the bottom of the tower and passes through the filter bed. The slightly alkaline circulating water enters from the top of the tower, is dispersed by the special nozzle, and falls freely through the filter bed. The special filter material can further disperse the biogas and circulating water, prolong the contact time and improve the washing effect. The circulating water containing sulfide flows into the regeneration tank from the bottom of desulfurization reaction tower.

二：再生池完成循环水中硫化物被氧化的过程，循环水中有大量的脱硫菌（主要为无色硫细菌等）将以硫化物为食，把硫化物转化为自身的营养物质，进入微生物的自身循环过程，从细菌体内排出单质硫和氢氧根，从而达到降解的目的。

2： The regeneration tank completes the oxidation process of sulfide in circulating water. A large number of desulfurization bacteria (mainly colorless sulfur bacteria) in circulating water will feed on sulfide, convert sulfide into their own nutrients, enter the self circulation process of microorganisms, and discharge elemental sulfur and hydroxyl from bacteria, so as to achieve the purpose of degradation.

再生池内创造循环水中脱硫菌的生存环境，再生池内的换热器给循环水提供热量，保证循环水温度在33-34度左右。曝气头给循环水提供氧气，保证循环水适当的溶解氧。脱硫菌通过消化循环水中的硫化物新陈代谢产生副产品单质硫和硫酸根，硫酸根会导致循环水的pH值降低，还需通过加药系统适当增加一些碱液中和这5%的硫酸根。

The regeneration tank creates a living environment for desulfurizing bacteria in circulating water, and the heat exchanger in the regeneration tank provides heat to the circulating water to ensure that the temperature of circulating water is about 33-34 degrees. The aeration head provides oxygen to the circulating water to ensure proper dissolved oxygen in the circulating water. Desulfurizing bacteria produce by-products elemental sulfur and sulfate by digesting sulfide metabolism in circulating water. Sulfate will reduce the pH value of circulating water. It is also necessary to add some alkali solution to neutralize the 5% sulfate through the dosing system.