一、沼氣發電介紹

　　1、 Introduction to Biogas Power Generation

　　1、沼氣主要成份沼氣是一種混合氣體，它的主要成分是甲烷，其次有二氧化碳、硫化氫(H2S)、氮及其他一些成分。沼氣的組成中，可燃成分包括甲烷、硫化氫、一氧化碳和重烴等氣體；不可燃成分包括二氧化碳、氮和氨等氣體。在沼氣成分中甲烷含量為55%～70%、二氧化碳含量為28%～44%、硫化氫平均含量為0.034%。沼氣依據其原料、生產過程等的不同, 其成分組成有很大的區別。

　　1. The main components of biogas are methane, followed by carbon dioxide, hydrogen sulfide (H2S), nitrogen, and other components. In the composition of biogas, combustible components include gases such as methane, hydrogen sulfide, carbon monoxide, and heavy hydrocarbons; Non combustible components include gases such as carbon dioxide, nitrogen, and ammonia. The methane content in biogas is 55% to 70%, the carbon dioxide content is 28% to 44%, and the average hydrogen sulfide content is 0.034%. The composition of biogas varies greatly depending on its raw materials, production process, and other factors.

　　2、沼氣的燃燒特性甲烷燃點在650～750℃之間，且沼氣中高濃度的二氧化碳對其有阻燃作用, 因此沼氣發動機的改裝過程中要盡量提高甲烷的燃燒速度。沼氣中的硫化氫對發電設備有很強的腐蝕作用, 硫化氫含量高于0.1% 的沼氣在用于發電時應嚴格脫硫。沼氣在燃燒過程中空氣的混入量對其燃燒特性有很大的影響。研究表明, 燃氣組成變化時火焰及其動態變化與火焰的分層結構有強烈的依賴關系。在沼氣中加入少量的氫氣可以明顯地改善沼氣的燃燒性能。在沼氣中加入少量的氫氣( 5%、10%、15%, 以能量計), 并以此為燃料, 在一定速度下研究了不同的氫氣比例對火花點燃式發動機的性能、排放、燃燒的影響。結果表明, 氫氣的加入明顯增加了沼氣的燃燒率, 減少了沼氣燃燒的限制, 在制動熱效率和制動能量上有明顯的改善，然而高于15%的氫含量并沒有導致相對較高的燃燒。

　　2. The combustion characteristics of biogas are that the ignition point of methane is between 650 and 750 ℃, and the high concentration of carbon dioxide in biogas has a flame retardant effect on it. Therefore, during the modification process of biogas engines, the combustion rate of methane should be maximized. The hydrogen sulfide in biogas has a strong corrosive effect on power generation equipment, and biogas with a hydrogen sulfide content higher than 0.1% should be strictly desulfurized when used for power generation. The amount of air mixed in during the combustion process of biogas has a significant impact on its combustion characteristics. Research has shown that the flame and its dynamic changes are strongly dependent on the layered structure of the flame when the gas composition changes. Adding a small amount of hydrogen to biogas can significantly improve its combustion performance. A small amount of hydrogen (5%, 10%, 15% in terms of energy) was added to biogas as fuel, and the effects of different hydrogen ratios on the performance, emissions, and combustion of spark ignition engines were studied at a certain speed. The results showed that the addition of hydrogen significantly increased the combustion rate of biogas, reduced the limitations of biogas combustion, and improved the braking thermal efficiency and braking energy. However, hydrogen content above 15% did not lead to relatively high combustion.

　　3、沼氣發酵工藝溫度沼氣產生于有機物質的厭氧發酵, 它是甲烷細菌的代謝產物. 產生沼氣的先決條件除了缺氧以外, pH值應該在6.5和7.5之間, 溫度應控制在一定范圍。

　　3. The temperature of biogas fermentation process produces biogas through anaerobic fermentation of organic matter, which is a metabolic product of methane bacteria The prerequisite for producing biogas is not only hypoxia, but also a pH value between 6.5 and 7.5, and a temperature controlled within a certain range.

　　沼氣池的溫度條件分為:①常溫發酵 (也稱為低溫發酵)10℃～30℃，在這個溫度條件下，嗜低溫菌的發酵期大約在90天至120天，產氣率可為0.15～0.3 m3/m3.d。②中溫發酵 30℃～45℃，在這個溫度條件下，中溫菌的發酵期大約25天至30天,池容產氣率可達1m3/m3.d左右。③高溫發酵 45℃～60℃，在這個溫度條件下，嗜熱菌的發酵期大約10天,池容產氣率可達2～2.5 m3/m3.d。沼氣發酵最經濟的溫度條件是35℃，即中溫發酵。

　　The temperature conditions of biogas digesters are divided into: ① room temperature fermentation (also known as low-temperature fermentation) at 10 ℃ to 30 ℃. Under this temperature condition, the fermentation period of low-temperature bacteria is about 90 to 120 days, and the gas production rate can be 0.15 to 0.3 m3/m3/d. ② Medium temperature fermentation at 30 ℃ to 45 ℃, under this temperature condition, the fermentation period of medium temperature bacteria is about 25 to 30 days, and the gas production rate of the pool capacity can reach about 1m3/m3/d. ③ High temperature fermentation at 45 ℃~60 ℃, under this temperature condition, the fermentation period of thermophilic bacteria is about 10 days, and the gas production rate of the tank capacity can reach 2-2.5 m3/m3/d. The most economical temperature condition for biogas fermentation is 35 ℃, which is medium temperature fermentation.

　　4、工藝流程介紹以下通過禽畜糞沼氣發電項目對沼氣發電作針對性的介紹：禽畜糞沼氣發電系統分為收集沉砂系統、厭氧反應系統、沼液儲存系統、生物脫硫系統、發電系統五大部分。禽畜糞收集沉砂系統由集水池、水解沉砂池、切碎機、厭氧進料泵及各池攪拌提升泵等組成。厭氧反應系統是由厭氧進料泵將物料打入厭氧反應器，通過攪拌、循環進行充分的厭氧反應。再由熱水罐提供的熱水保證反應器溫度適中，以獲得穩定的厭氧反應和沼氣輸出。沼液儲存系統包括沼液暫存池、固液分離機及沼液出水池等。沼液暫存池主要是收集沼氣，固液分離機是將沼液暫存池中的固體分離送入肥料廠，液體進入沼液出水池中。生物脫硫系統包括脫硫塔、空壓機、干燥機、循環水泵、儲氣柜等設備將系統中產生的沼氣進行凈化處理、儲存以達到進入燃燒發電系統的要求。發電系統是將沼氣通過內燃機、燃氣輪機等其他燃燒機組產生動能帶動發電機發電。

　　4. The following is a targeted introduction to biogas power generation through the livestock manure biogas power generation project: The livestock manure biogas power generation system is divided into five parts: collection and sedimentation system, anaerobic reaction system, biogas slurry storage system, biological desulfurization system, and power generation system. The livestock manure collection and sedimentation system consists of a collection tank, a hydrolysis sedimentation tank, a chopper, an anaerobic feed pump, and mixing and lifting pumps for each tank. The anaerobic reaction system is a process in which materials are pumped into an anaerobic reactor by an anaerobic feed pump, and undergo thorough anaerobic reactions through agitation and circulation. The hot water provided by the hot water tank ensures a moderate temperature in the reactor to achieve stable anaerobic reactions and biogas output. The biogas slurry storage system includes a biogas slurry temporary storage tank, a solid-liquid separator, and a biogas slurry effluent tank. The biogas slurry temporary storage tank is mainly used to collect biogas. The solid-liquid separator separates the solids in the biogas slurry temporary storage tank and sends them to the fertilizer plant, while the liquid enters the biogas slurry outlet tank. The biological desulfurization system includes desulfurization tower, air compressor, dryer, circulating water pump, gas storage tank and other equipment to purify and store the biogas generated in the system to meet the requirements for entering the combustion power generation system. The power generation system generates kinetic energy from biogas through other combustion units such as internal combustion engines and gas turbines to drive the generator to generate electricity.

　　5、沼氣發電機組裝置大功率沼氣發電機組是沼氣工業化利用的關鍵設備。在我國，有全部使用沼氣的單燃料沼氣發電機組及部分使用沼氣的雙燃料沼氣-柴油發電機組。?單燃料沼氣發電機組工作原理及優點：?將“空氣沼氣”的混合物放在氣缸內壓縮，用火花塞使其燃燒，通過火花塞的往復運動得到動力，然后連接發電機發電。?優點：①不需要輔助燃料油及其供給設備；②燃料為一個系統，在控制方面比可燒兩種燃料的發電機組簡單；③發電機組價格較低。?雙燃料沼氣-柴油發電機組工作原理及優點：?將“空氣燃燒氣體”的混合物放在氣缸內壓縮，用點火燃料使其燃燒，通過火花塞的往復運動得到動力，然后連接發電機發電。?優點：①用液體燃料或氣體燃料都可工作；②對沼氣的產量和甲烷濃度的變化能夠適應；③如由用氣體燃料轉為用柴油燃料，在停止工作后，發電機組內不殘留未燃燒的氣體。?缺點：①工作受到供給的沼氣的數量和質量的影響；②用氣體燃料工作時也需要添加液體輔助燃料供給設備；③控制機構稍復雜；④價格較單燃料式發電機組稍高。

　　5. The high-power biogas generator set is a key equipment for the industrial utilization of biogas. In China, there are single fuel biogas generator sets that all use biogas and some dual fuel biogas diesel generator sets that use biogas. Working principle and advantages of a single fuel biogas generator set: The mixture of "air biogas" is compressed in a cylinder, burned with a spark plug, and powered by the reciprocating motion of the spark plug, and then connected to a generator to generate electricity. Advantages: ① No need for auxiliary fuel oil and its supply equipment; ② Fuel is a system that is simpler to control than a generator set that can burn two types of fuel; ③ The price of generator sets is relatively low. Working principle and advantages of dual fuel biogas diesel generator set: The mixture of "air combustion gas" is compressed in the cylinder, ignited with fuel, and powered by the reciprocating motion of the spark plug, and then connected to the generator to generate electricity. Advantages: ① It can work with both liquid and gas fuels; ② Capable of adapting to changes in biogas production and methane concentration; ③ If gas fuel is switched to diesel fuel, there will be no unburned gas remaining in the generator set after it stops working. Disadvantages: ① The work is affected by the quantity and quality of the supplied biogas; ② When working with gas fuel, it is also necessary to add liquid auxiliary fuel supply equipment; ③ The control mechanism is slightly complex; ④ The price is slightly higher than that of single fuel generator sets.

　　6、沼氣發電效率一方氣平均發電1.5～2kwh。發電效率：國產30%左右，進口38%-46%。單機功率：國產2000kw以下，進口10MW以下。進口機組的突出優點在于效率較高，單位沼氣的發電效率高，但是投資成本和維護維修成本高。而國產機組近年來技術水平有很大提升，尤其是在對CH4濃度適應方面和每KW的造價方面都具有比較明顯的優勢，具有較好的性價比，但故障率相對高些，機組在線率相對較低。進口機組造價是國產機組的2-3倍。沼氣品質會直接影響發電效率。積水導致了凝結水在管道的大量聚集，機組的可用率和發電功率大幅度下降；含塵量過高導致壓力損耗過大，且機組內部缸體損耗嚴重；壓力、溫度等不符合機組要求，機組頻繁跳機，可用率大幅下降且增加了維護檢修成本。而經過改造后的氣體預處理，機組的發電量增加了70%。所以，氣體品質處理的效果如何，直接影響到最終的機組工作效率，從而影響收益。

　　6. The efficiency of biogas power generation is 1.5-2kWh per cubic meter of gas on average. Power generation efficiency: about 30% domestically produced, 38% -46% imported. Single machine power: below 2000kw domestically, below 10MW imported. The outstanding advantage of imported units is high efficiency, with a high power generation efficiency per unit of biogas, but high investment and maintenance costs. In recent years, the technological level of domestically produced units has greatly improved, especially in terms of adapting to CH4 concentration and cost per KW, which have obvious advantages and good cost-effectiveness. However, the failure rate is relatively high and the online rate of the units is relatively low. The cost of imported units is 2-3 times that of domestic units. The quality of biogas directly affects the efficiency of power generation. The accumulation of water caused a large amount of condensed water to accumulate in the pipeline, resulting in a significant decrease in the availability and power generation of the unit; Excessive dust content leads to excessive pressure loss, and the internal cylinder of the unit is severely damaged; The pressure, temperature, etc. do not meet the requirements of the unit, and the unit frequently trips, resulting in a significant decrease in availability and an increase in maintenance and repair costs. After the transformation of gas pretreatment, the power generation of the unit increased by 70%. So, the effectiveness of gas quality treatment directly affects the final efficiency of the unit, thereby affecting the revenue.

　　7、沼氣發電機組裝機容量決定因素沼氣發電機組的裝機大小（裝機容量）取決于以下兩個因素：一是沼氣量，沼氣量越大，裝機容量就大；二是負載（這里指所有用電設備單位小時內耗電量）大小，特別是中小型的養殖規模受這個因素影響較大。

　　7. The determining factor for the assembly capacity of biogas generators is the installed size (installed capacity) of the biogas generator set, which depends on two factors: first, the amount of biogas, the larger the amount of biogas, the larger the installed capacity; The second factor is the size of the load (referring to the electricity consumption per unit hour of all electrical equipment), especially for small and medium-sized aquaculture scales, which are greatly affected by this factor.

　　8、沼氣發電脫硫原因沼氣里面的硫主要是以硫化氫(H2S)的形式存在，分子式為H2S，分子量為34.076，標準狀況下是一種易燃的酸性氣體，無色，低濃度時有臭雞蛋氣味，有劇毒。硫化氫是一種重要的化學原料。硫化氫氣體在沼氣發動機缸體里高溫燃燒環境下，形成SO（硫氧）化物，對發動機的缸體、活塞、缸套等有腐蝕性，嚴重影響沼氣發動機的使用壽命。所以不僅僅沼氣發電需要脫硫，其實生活用氣也要脫硫，只是脫硫要求沒有那么高，如果不脫硫對灶具破壞比較大。

　　8. The reason for desulfurization in biogas power generation is that the sulfur in biogas mainly exists in the form of hydrogen sulfide (H2S), with a molecular formula of H2S and a molecular weight of 34.076. Under standard conditions, it is a flammable acidic gas, colorless, and has a strong egg odor at low concentrations. It is highly toxic. Hydrogen sulfide is an important chemical raw material. Hydrogen sulfide gas forms sulfur oxides (SOs) in the high-temperature combustion environment of biogas engine cylinders, which are corrosive to the cylinder body, piston, cylinder liner, etc. of the engine, seriously affecting the service life of biogas engines. So not only does biogas power generation require desulfurization, but domestic gas also needs desulfurization, although the desulfurization requirements are not as high. If desulfurization is not carried out, it will cause significant damage to the stove.

　　9、沼氣發電輔助設備沼氣發電需要具備沼氣池、輸氣管道、儲氣柜（袋）、沼氣脫硫脫水，如果壓力不夠還要增加一套防腐防爆增壓設備，最后是沼氣發電機組。如果要用到并網的話，還需一套并網柜。

　　9. Biogas power generation auxiliary equipment requires biogas digesters, gas transmission pipelines, gas storage tanks (bags), biogas desulfurization and dehydration. If the pressure is not enough, a set of anti-corrosion and explosion-proof boosting equipment should be added, and finally, a biogas generator set. If grid connection is required, a set of grid connected cabinets is also needed.

　　10、沼氣發電機組余熱回收沼氣發電機組在發電過程中，煙氣溫度達到500度左右，發動機里的缸套水也有80度左右，可通過板式熱交換器把里面的熱量交換出來，如果量大可以給我們供暖氣，如果量小可以供我們生活用水。同時，余熱也可以作為作為沼氣發生器的加溫熱源。

　　10. Waste heat recovery of biogas generator set During the power generation process, the flue gas temperature reaches about 500 degrees, and the cylinder liner water in the engine is also about 80 degrees. The heat inside can be exchanged through a plate heat exchanger. If the amount is large, it can provide us with heating, and if the amount is small, it can provide us with domestic water. Meanwhile, waste heat can also serve as a heating source for biogas generators.

　　二、沼氣發電障礙1、成本障礙燃料供應不論在數量還是在成本控制上，均有較大的不確定性。由于飼養方式、飼養條件、飼料成分和配方、畜禽品種等的不同，牲畜的糞便產量差異很大。以50千克重的豬為例，每頭每天的產糞量，低的僅有1.75千克，高的達到6千克。因此，若對特定養殖場（小區）的畜禽實際產糞量無充分把握時，最好進行實測。目前，全世界農業沼氣工程最發達的德國，其95% 的沼氣工程采用混合原料發酵，原料的保證度高。發酵原料中：47% 為能源作物（多為玉米青貯）、41%為畜禽糞便、10% 為有機廢棄物、2% 為工農業生產加工廢棄物。我國沼氣工程的原料較為單一，原料保證度低。應加強對作物秸稈、有機蔬菜的爛菜葉、雜草、餐廚垃圾等沼氣發酵原料的開發利用；另外，能源作物的青貯一般采用機收后溝壕式堆積加覆蓋的方法、十分簡便，投資很少，應成為今后解決原料短缺的重要途徑。生產沼氣的厭氧發酵過程，單一批次的物料投入后周期較長，一般來說都超過二十天，這種情況下，要形成一定的生產規模，就需要發酵設施的規模非常大，加上附屬的沼氣發電設施、物料運輸和儲存設施、環保治理設施、配電設施等等，項目整體的用地規模將比較大。

　　2、 Obstacle to biogas power generation: 1. Cost obstacle. Fuel supply has significant uncertainty in both quantity and cost control. Due to differences in feeding methods, feeding conditions, feed composition and formula, and livestock breeds, there are significant variations in the fecal production of livestock. Taking a pig weighing 50 kilograms as an example, the daily manure production of each pig ranges from 1.75 kilograms to 6 kilograms. Therefore, if there is insufficient confidence in the actual manure production of livestock and poultry in a specific breeding farm (community), it is best to conduct actual measurements. At present, Germany, which has the most developed agricultural biogas engineering in the world, uses mixed raw material fermentation for 95% of its biogas engineering, with high guarantee of raw materials. In the fermentation raw materials, 47% are energy crops (mostly corn silage), 41% are livestock manure, 10% are organic waste, and 2% are industrial and agricultural production and processing waste. The raw materials for biogas engineering in our country are relatively single, and the guarantee of raw materials is low. We should strengthen the development and utilization of biogas fermentation materials such as crop straw, organic vegetable leaves, weeds, and kitchen waste; In addition, the silage of energy crops is generally harvested by machines and then stacked and covered in trenches, which is very simple and requires little investment. It should become an important way to solve the shortage of raw materials in the future. The anaerobic fermentation process for producing biogas has a long cycle after a single batch of materials is input, generally exceeding 20 days. In this case, to form a certain production scale, a very large scale of fermentation facilities is required, along with ancillary biogas power generation facilities, material transportation and storage facilities, environmental protection treatment facilities, power distribution facilities, etc. The overall land use scale of the project will be relatively large.

　　2、技術障礙我國沼氣發動機的開發研究主要集中在內燃機系列上，一般只是對柴油機和汽油機進行較淺層次的改裝，對發動機的熱工性能研究不深，由于產品質量不過關，在運行使用中出現諸多問題，給用戶帶來不便，從而影響其發展進程。導致這種情況的根本原因是沒有對沼氣發動機進行深入的研究，技術不過關，缺乏足夠的生產實踐。致使發動機在運行中產生熱負荷高、可靠性差、起動困難；另外我國研制的全燒沼氣發動機的排氣溫度過高，氣閥易燒壞，使氣缸蓋等成為易損件等諸多技術問題。

　　2. The development and research of biogas engines in China mainly focus on the internal combustion engine series due to technical barriers. Generally, only superficial modifications are made to diesel and gasoline engines, and the thermal performance of the engines is not deeply studied. Due to poor product quality, many problems arise during operation and use, causing inconvenience to users and affecting their development process. The fundamental reason for this situation is the lack of in-depth research on biogas engines, inadequate technology, and insufficient production practice. Causing high thermal load, poor reliability, and difficulty in starting the engine during operation; In addition, the exhaust temperature of the fully burned biogas engine developed in our country is too high, and the valve is prone to burning out, making the cylinder head and other vulnerable parts and other technical problems.

　　3、市場障礙由于我國沼氣發動機存在許多問題，先前應用國產發電機組的沼氣發電工程有許多長期處于停機狀態。這就使后來發展的絕大多數沼氣工程放棄了沼氣發電方式，轉而尋求其他的利用途徑。少數沼氣發電工程(如天津、杭州等)依靠貸款引進購買較為成熟的國外發電機組設備來維持運行。我國生產廠家則由于技術不夠成熟而造成買方市場的嚴重匱乏，沼氣發動機和發電機組無法形成規模化批量生產，使科研生產單位缺乏相關的研究經費，沒有對其作深入研究開發的積性，不能提供質量過關的產品，進一步阻礙產品的市場化進程，對生產科研單位自身以及沼氣發電領域的發展都不利。無明顯優勢企業，行業空間集中于設備、工程市場。從國內沼氣工程使用沼氣發電機組情況來看,國外和國內產品各占50%左右,國外產品在效率上優勢明顯,而國內產品在價格、售后服務方面優勢突出。而沼氣發酵、凈化、存儲設備制造相對簡單,參與企業眾多。整體而言,目前沼氣發電設備、沼氣發電運營并無優勢企業,市場仍處于培育中。沼氣發電市場的參與者主要有兩類：發電設備制造商和發電運營商。發電運營商主要有河南百川暢銀實業等,上市公司中桑德環境、東江環保等環保企業有所涉及,但該業務占比仍較小；而發電設備制造商主要有國外顏巴赫（GE）、卡特比勒、道依茨等，國內以勝動、石油濟柴、濰柴動力三大沼氣發電設備制造商為主，此外康達(康明斯)、濰坊伊達能、無錫柴油等企業也有生產。沼氣發電市場不規范，沒有相應的較為完善的行業標準，也不利于其商業化開發和利用。盡管沒有沼氣發電入網裝機容量的門限，但由于各地條件不同，電網企業有時會對并網發電提出最小裝機容量要求。絕大多數畜禽養殖場沼氣工程規模都不大，以萬頭豬場為例，依據其沼氣池產氣量可配備50千瓦發電機組（按每天發電500千瓦時，工作時間10小時配備），但仍遠低于一些地方電網企業的要求，所發電力不能入網銷售，實現不了收益。即便發電能上網，由于發電成本偏高，大多數情況下，銷售額加上電價補貼都不能與成本相抵。規模小了，發電也基本上不了網；規模大了，沼渣沼液的去向和處理處置成本又成問題。很多沼氣工程處于“左右為難”的狀態。

　　3. Market obstacles: Due to many problems with biogas engines in China, many biogas power generation projects that previously used domestically produced generators have been in a state of long-term shutdown. This led the vast majority of biogas projects that developed later to abandon biogas power generation and instead seek other ways of utilization. A few biogas power generation projects (such as Tianjin, Hangzhou, etc.) rely on loans to introduce and purchase mature foreign power generation equipment to maintain operation. Chinese manufacturers, on the other hand, suffer from a severe shortage of buyer's markets due to immature technology. Biogas engines and generator sets cannot be mass-produced on a large scale, resulting in a lack of research funding for scientific research and production units, a lack of enthusiasm for in-depth research and development, and an inability to provide high-quality products. This further hinders the marketization process of products and is detrimental to the development of production and research units as well as the field of biogas power generation. There are no obvious advantageous enterprises, and the industry space is concentrated in the equipment and engineering markets. From the use of biogas generators in domestic biogas projects, foreign and domestic products each account for about 50%. Foreign products have obvious advantages in efficiency, while domestic products have prominent advantages in price and after-sales service. The manufacturing of biogas fermentation, purification, and storage equipment is relatively simple, and there are many participating enterprises. Overall, there are currently no advantageous enterprises in biogas power generation equipment and operation, and the market is still under cultivation. There are mainly two types of participants in the biogas power generation market: power generation equipment manufacturers and power generation operators. The main power generation operators include Henan Baichuan Changyin Industry, among which listed companies such as Sande Environment and Dongjiang Environmental Protection are involved, but the proportion of this business is still relatively small; The main manufacturers of power generation equipment include foreign companies such as Yanbach (GE), Caterpillar, and Deutz. In China, the three major manufacturers of biogas power generation equipment are Shengdong, Petroleum Jichai, and Weichai Power. In addition, companies such as Cummins, Weifang Idaneng, and Wuxi Diesel also produce. The biogas power generation market is not standardized, and there are no corresponding relatively complete industry standards, which is also not conducive to its commercial development and utilization. Although there is no threshold for the installed capacity of biogas power generation connected to the grid, due to different conditions in various regions, power grid enterprises sometimes require a minimum installed capacity for grid connected power generation. The vast majority of livestock and poultry breeding farms have small-scale biogas projects. Taking a pig farm with ten thousand heads as an example, based on the gas production of its biogas digesters, a 50 kW generator set can be equipped (with a daily power generation of 500 kWh and a working time of 10 hours), but it is still far below the requirements of some local power grid enterprises, and the generated electricity cannot be sold on the grid, resulting in no revenue. Even if power generation can be connected to the grid, due to the high cost of power generation, in most cases, sales revenue plus electricity price subsidies cannot offset the cost. The scale is small, and the power generation is basically unable to connect to the grid; As the scale increases, the disposal cost of sludge and slurry becomes a problem again. Many biogas projects are in a dilemma.

　　制沼系統設備1、預處理：側式攪拌機9臺，螺旋除砂機5臺，立式攪拌機4臺，螺旋刮砂機3臺，一級提升泵2臺，二級提升泵2臺，切割機+凸輪泵2套，污水泵2臺2、厭氧反應器：底部側攪拌機8+8共16臺，頂部破殼機16臺，立式攪拌機8臺，內循環泵4臺，出渣泵2臺，沼氣在線組分分析儀2臺，厭氧反應器8座，沼氣氣體流量計9臺3、生物脫硫：一套4、雙膜儲氣柜：雙膜儲氣柜1套，鼓風機2臺及配套控制柜1套5、沼氣增壓：火炬一套，冷干機一套，羅茨風機3臺，沼氣氣體流量計3臺，電動閥門若干6、沼氣鍋爐：蒸汽鍋爐及其配套設施2套，熱儲罐1座，冷水罐1座，熱水循環泵4臺，制軟水設備一套7、PLC自動化控制系統一套，通風系統發電系統發電機4臺，發電機控制柜4個，余熱鍋爐4套，變壓器4套提純壓縮脫硫塔2座，冷卻系統3件，控制系統3件，MCC、防爆電機3件，系統成撬3件，螺桿壓縮機及機頭總成3件有機肥固液分離機4套，沼氣儲存池7座公共設施廠區路燈，廠區供暖系統，廠區消防系統，廠區空調系統，廠區給排水系統，廠區監控系統，廠區道路

　　1. Pre treatment of biogas production system equipment: 9 side mixers, 5 spiral sand removal machines, 4 vertical mixers, 3 spiral sand scrapers, 2 first stage lifting pumps, 2 second stage lifting pumps, 2 cutting machines+cam pumps, 2 sewage pumps. 2. Anaerobic reactors: 16 bottom side mixers 8+8, 16 top shell breaking machines, 8 vertical mixers, 4 internal circulation pumps, 2 slag discharge pumps, 2 online biogas component analyzers, 8 anaerobic reactors, 9 biogas gas flow meters. 3. Biological desulfurization: 1 set. 4. Double membrane gas storage tank: 1 set of double membrane gas storage tank, 2 blowers and matching control cabinet. 5. Biogas boosting: one set of torch, one set of refrigerated dryer, three Roots blowers, three biogas gas flow meters, and several electric valves. 6. Biogas boiler: two sets of steam boilers and their supporting facilities, one hot storage tank, one cold water tank, and four hot water circulation pumps, One set of soft water equipment, one set of PLC automation control system, four generators for the ventilation system power generation system, four generator control cabinets, four sets of waste heat boilers, four sets of transformers, two purification and compression desulfurization towers, three cooling systems, and three control systems, MCC、 3 explosion-proof motors, 3 system components, 3 screw compressors and head assemblies, 4 sets of organic fertilizer solid-liquid separators, 7 biogas storage tanks, public facilities, factory street lights, factory heating system, factory fire protection system, factory air conditioning system, factory water supply and drainage system, factory monitoring system, factory roads