沼氣中含有硫化氫,分子式為H2S,硫化氫為易燃?;?,與空氣混合能形成爆炸性混合物,遇明火、高熱能引起燃燒爆炸,加上硫化氫遇水后會對鋼材產(chǎn)生較強的腐蝕特性,因此沼氣提純精制生物天然氣的預(yù)處理工序的核心即是脫除硫化氫。
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.
不同的有機廢棄物在厭氧狀態(tài)下產(chǎn)生的沼氣中的硫化氫濃度有高有低,差異比較大。造紙工業(yè)、發(fā)酵工業(yè)等由于在生產(chǎn)過程中有含硫的介質(zhì)加入,生產(chǎn)廢水產(chǎn)生的沼氣含硫化氫的濃度便比較高。如造紙行業(yè)的沼氣可高達10000-35000ppm,淀粉工業(yè)沼氣一般在10000ppm左右,生活垃圾填埋沼氣則由于產(chǎn)生過程中相對較少有硫介質(zhì)參與,因此硫化氫含量較低,一般在1000ppm以內(nèi)。
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.
在我國,目前沼氣的生產(chǎn)加工技術(shù)和商業(yè)化運行系統(tǒng)也已經(jīng)逐漸成熟,通過自主創(chuàng)新、引進并消化吸收了國外成熟的高含固量的有機廢棄物厭氧消化技術(shù),其中以谷物秸稈、畜禽糞便、城市有機垃圾為處理對象的大型沼氣工程也取得了突破性進展,因此,相應(yīng)的沼氣凈化提純工藝技術(shù)也得到發(fā)展,形成了一系列相對比較成熟的技術(shù)。
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.