鑒于全球化石燃料所面臨的枯竭危機(jī),對(duì)生物質(zhì)燃料的開(kāi)發(fā)和應(yīng)用已經(jīng)成為各國(guó)關(guān)注的。其中,沼氣和生物天然氣作為可再生能源,具有利用成本低、對(duì)環(huán)境無(wú)污染的特點(diǎn),是替代常規(guī)化石能源的環(huán)保燃料。隨著大型沼氣、生物天然氣工程的快速發(fā)展,
沼氣脫硫提純?yōu)楦吒郊又瞪锶細(xì)獾男枨笕找嫫惹校託鈨艋峒兗夹g(shù)得到了不同程度的應(yīng)用和發(fā)展。
In view of the global fossil fuel depletion crisis, the development and application of biomass fuel has become the focus of attention. Among them, biogas and biogas, as renewable energy, have the characteristics of low utilization cost and no pollution to the environment. They are high-quality environmental protection fuels instead of conventional fossil energy. With the rapid development of large-scale biogas and biogas projects, the demand of biogas desulfurization and purification to high value-added biogas is increasingly urgent, and the biogas purification technology has been applied and developed in different degrees.
沼氣提純精制生物天然氣脫硫技術(shù)
Desulfurization technology of biogas purification and purification
國(guó)內(nèi)外用于
沼氣脫硫的常見(jiàn)工藝有干法脫硫、PSA脫硫、化學(xué)法脫硫、生物脫硫、膜別離法脫硫等。而在沼氣提純精制生物天然氣領(lǐng)域,主要有活性碳系或氧化鐵系干法脫硫、堿洗脫硫、生物脫硫。其間,生物脫硫因?yàn)橄蛸|(zhì)料氣中引入了氧氮等雜質(zhì)氣體,因而只能用于沼氣發(fā)電而不能用于沼氣精制,以下就對(duì)沼氣提純中的脫硫技能及其特點(diǎn)進(jìn)行說(shuō)明:
The common processes used for biogas desulfurization at home and abroad are dry desulfurization, PSA desulfurization, chemical desulfurization, biological desulfurization, membrane separation desulfurization, etc. In the field of biogas purification and purification, there are mainly activated carbon or iron oxide dry desulfurization, alkali washing desulfurization and biological desulfurization. Meanwhile, bio desulfurization can only be used for biogas power generation but not for biogas purification because of the introduction of impurity gases such as oxygen and nitrogen into the feed gas. The following describes the desulfurization skills and characteristics in biogas purification:
1干法脫硫
1 dry desulfurization
干法脫硫是經(jīng)過(guò)固體脫硫劑將氣態(tài)硫化物轉(zhuǎn)化為固體硫化物,該法特點(diǎn)是設(shè)備制造簡(jiǎn)單、操作簡(jiǎn)便,凈化度較高,脫硫劑可再生。但缺點(diǎn)是價(jià)值很低,達(dá)到飽和硫容后就須更換。一般用于氣量小、硫化氫含量低,需求深度脫硫的氣體脫硫,且對(duì)氣溫和水份有一定的要求。脫硫劑一般分為活性碳系、氧化鐵系、鋅錳系幾類(lèi)。脫硫塔多為固定床層,多塔串聯(lián)運(yùn)用,用過(guò)的脫硫劑可經(jīng)過(guò)摻煤燃燒或廠(chǎng)家收回處理再利用。
Dry desulfurization is the conversion of gaseous sulfide to solid sulfide by solid desulfurizer, which is characterized by simple equipment manufacturing, simple operation, high purification degree and renewable desulfurizer. But the disadvantage is that the value is very low, and it needs to be replaced after reaching the saturated sulfur capacity. It is generally used for gas desulfurization with small gas volume, low hydrogen sulfide content and deep desulfurization demand, and has certain requirements for air temperature and water content. Desulfurizer is generally divided into activated carbon system, iron oxide system, zinc manganese system. The desulfurizer is mostly fixed bed, which is used in series. The used desulfurizer can be burned with coal or recycled by the manufacturer.
2PSA和膜別離法脫硫
2psa and membrane separation desulfurization
變壓吸附(PSA)的原理是以吸附劑對(duì)不同的氣體在不同的壓力下,氣體吸附速率和量的不同而完成氣體的別離。膜別離法則是利用氣體分子大小不同能選擇性透過(guò)膜和不同氣體穿透速率不同而完成氣體的別離。這兩種辦法別離出的硫化氫都需求再處理,同時(shí)對(duì)甲烷氣帶來(lái)較大的損失。
The principle of PSA is to separate different gases with different adsorption rate and amount under different pressure. The separation rule of membrane is to use the gas molecules with different sizes to selectively penetrate the membrane and different gas penetration rates to complete gas separation. The hydrogen sulfide separated from these two methods needs to be reprocessed, and at the same time, it will bring great loss to methane gas.
另外,膜別離法中運(yùn)用的膜要常常更換,運(yùn)轉(zhuǎn)成本較高,而變壓吸附劑和化學(xué)吸收劑可循環(huán)運(yùn)用,因而,變壓吸附法相關(guān)于膜別離技能的實(shí)際運(yùn)用更廣。
In addition, the membrane used in membrane separation method should be replaced frequently with high operation cost, while the PSA and chemical absorbent can be recycled, so the practical application of PSA on membrane separation technology is more extensive.
3堿洗脫硫
3 alkali washing desulfurization
堿洗脫硫是指選用堿液循環(huán)運(yùn)用進(jìn)行脫硫,根據(jù)再生辦法不同可分為:化學(xué)法和生物法。兩種辦法在脫硫、硫磺處理、配堿等工序上均相同,其間選用催化劑再生的工藝叫化學(xué)再生脫硫,選用生物菌再生的工藝叫生物再生脫硫。
Alkali washing desulfurization refers to the use of alkali liquor circulation for desulfurization, which can be divided into chemical method and biological method according to different regeneration methods. The two methods are the same in desulfurization, sulfur treatment, alkali preparation and other processes. The process of catalyst regeneration is called chemical regeneration desulfurization, and the process of biological bacteria regeneration is called biological regeneration desulfurization.
除了再生辦法不同之外,這兩種辦法主要的運(yùn)用領(lǐng)域也各自不同,其間生物再生式堿洗脫硫工藝在沼氣發(fā)電氣體預(yù)處理工序中有一定的運(yùn)用,在沼氣精制天然氣的氣體脫除硫化氫實(shí)際項(xiàng)目中則沒(méi)有運(yùn)用,化學(xué)再生法相對(duì)而言運(yùn)用則更廣一些。
In addition to the different regeneration methods, the main application fields of the two methods are also different. In the meantime, the biological regeneration alkali washing desulfurization process has certain application in the gas pretreatment process of biogas power generation, but not in the actual project of gas hydrogen sulfide removal of biogas refined natural gas. The chemical regeneration method is relatively more widely used.
5生物脫硫
5 biological desulfurization
生物脫硫工藝是一種新型的脫硫工藝,越來(lái)越遭到企業(yè)的歡迎。生物脫硫的基本原理是利用硫桿菌屬和絲硫茵屬類(lèi)微生物代謝的效果,將硫化氫與氧氣合成為硫酸鹽進(jìn)而除去沼氣中的硫氫,脫硫產(chǎn)品為硫酸鹽。
Biological desulfurization process is a new type of desulfurization process, which is more and more popular in enterprises. The basic principle of biological desulfurization is to use the metabolism effect of Thiobacillus and thiomyces to synthesize hydrogen sulfide and oxygen into sulfate and then remove hydrogen sulfide in biogas, and the desulfurization product is sulfate.
盡管其運(yùn)用較為便捷,運(yùn)轉(zhuǎn)成本較低,但由于脫硫過(guò)程中同時(shí)引入了雜質(zhì)氣體,在后續(xù)工序中無(wú)法去除,同時(shí)生物脫硫剛剛起步,技能還不成熟,大多運(yùn)用進(jìn)口技能和設(shè)備,因而投資成本相對(duì)較高,大約為常規(guī)干法脫硫的3~5倍。
Although it is convenient to use and low in operation cost, due to the introduction of impurity gas in the desulfurization process, it can not be removed in the subsequent process. At the same time, the biological desulfurization is just in its infancy and the skills are not mature. Most of the imported skills and equipment are used, so the investment cost is relatively high, about 3-5 times of the conventional dry desulfurization.
The above is a brief introduction to the desulfurization technology of biogas purification and purification. For more information, please click biogas desulfurization http://www.zzzop.cn Website.