沼气中含有硫化氢,分子式为H2S,硫化氢为易燃危化品,与空气混合能形成爆炸性混合物,遇明火、高热能引起燃烧爆炸,加上硫化氢遇水后会对钢材产生较强的腐蚀特性,因此沼气提纯精制生物天然气的预处理工序的核心即是脱除硫化氢。
Biogas contains hydrogen sulfide, whose molecular formula is H2S. Hydrogen sulfide is flammable and dangerous chemicals. It can form explosive mixture when mixed with air. It can cause combustion and explosion in case of open fire and high heat. In addition, hydrogen sulfide will produce strong corrosion characteristics on steel when it meets with water. Therefore, the core of the pretreatment process of biogas purification is to remove hydrogen sulfide.
不同的有机废弃物在厌氧状态下产生的沼气中的硫化氢浓度有高有低,差异比较大。造纸工业、发酵工业等由于在生产过程中有含硫的介质加入,生产废水产生的沼气含硫化氢的浓度便比较高。如造纸行业的沼气可高达10000-35000ppm,淀粉工业沼气一般在10000ppm左右,生活垃圾填埋沼气则由于产生过程中相对较少有硫介质参与,因此硫化氢含量较低,一般在1000ppm以内。
The concentration of hydrogen sulfide in biogas produced by different organic wastes under anaerobic condition varies greatly. Due to the addition of sulfur-containing medium in the production process of paper industry and fermentation industry, the concentration of hydrogen sulfide in biogas produced by production wastewater is relatively high. For example, the biogas in papermaking industry can be as high as 10000-35000ppm, that in starch industry is generally around 10000ppm, and that in domestic waste landfill is relatively less sulfur medium involved in the production process, so the content of hydrogen sulfide is relatively low, generally within 1000ppm.
在我国,目前沼气的生产加工技术和商业化运行系统也已经逐渐成熟,通过自主创新、引进并消化吸收了国外成熟的高含固量的有机废弃物厌氧消化技术,其中以谷物秸秆、畜禽粪便、城市有机垃圾为处理对象的大型沼气工程也取得了突破性进展,因此,相应的沼气净化提纯工艺技术也得到发展,形成了一系列相对比较成熟的技术。
In China, the production and processing technology and commercial operation system of biogas have gradually matured. Through independent innovation, introduction and digestion of foreign mature and advanced anaerobic digestion technology of organic waste with high solid content, the large-scale biogas project with grain straw, livestock manure and urban organic waste as treatment objects has also made breakthrough progress. Therefore, the corresponding countermeasures are put forward The technology of biogas purification and purification has also been developed, forming a series of relatively mature technologies.