沼氣裝置的使用和管理

　　The use and management of biogas equipmen

　　時(shí)必須控制空氣流量，使脫硫劑床層溫度穩(wěn)定在60℃左右。脫硫劑的活性隨再生次數(shù)逐漸下降，一般使用2～5次即更換新的脫硫劑。沼氣生產(chǎn)管理沼氣是一種易燃易爆、窒息性氣體，在沼氣生產(chǎn)管理中宜注意以下方面：①在沼氣生產(chǎn)區(qū)、沼氣發(fā)電室等處，禁止放置易燃、易爆物品，嚴(yán)禁煙火，并須備有消防設(shè)備。用氣設(shè)備均有阻止回火裝置（防火器），并保持良好狀態(tài)。

　　It is necessary to control the air flow rate to stabilize the temperature of the desulfurizer bed at around 60 ℃. The activity of desulfurizer gradually decreases with the number of regenerations, and it is generally replaced with a new desulfurizer after 2-5 uses. Biogas production management: Biogas is a flammable, explosive, and suffocating gas. In biogas production management, attention should be paid to the following aspects: ① Flammable and explosive materials are prohibited from being placed in biogas production areas, biogas power generation rooms, etc. Smoking is strictly prohibited, and fire-fighting equipment must be prepared. All gas equipment is equipped with anti backfire devices (fire extinguishers) and maintained in good condition.

　　對(duì)驗(yàn)收合格的沼氣工程設(shè)施必須進(jìn)行科學(xué)使用和管理，才能充分發(fā)揮工程效益和安全運(yùn)行。使用和管理主要有以下內(nèi)容。

　　Scientific use and management of qualified biogas engineering facilities must be carried out in order to fully utilize engineering benefits and ensure safe operation. The use and management mainly include the following contents.

　　投產(chǎn)前的試運(yùn)轉(zhuǎn)

　　Trial operation before production

　　新建沼氣池應(yīng)灌水試壓，使氣壓增至2940帕。如24小時(shí)內(nèi)壓力下降小于10%，則可認(rèn)為池體密封性符合要求，否則重新采取密封措施，再按上述方法檢驗(yàn)，直至合格為止。與沼氣池配套的所有管道、閥門均須根據(jù)其各自的運(yùn)行技術(shù)條件，分別按照設(shè)計(jì)標(biāo)準(zhǔn)進(jìn)行檢驗(yàn)。對(duì)于各種壓力表和流量計(jì)，以及液面、溫度、pH等指示、儀表，加熱器、攪拌器、電機(jī)、水泵等設(shè)備，按各自的產(chǎn)品質(zhì)量檢驗(yàn)標(biāo)準(zhǔn)和設(shè)計(jì)要求進(jìn)行單機(jī)調(diào)試和整個(gè)系統(tǒng)聯(lián)動(dòng)運(yùn)行，使全套設(shè)備按工藝要求處于正常技術(shù)狀態(tài)。

　　Newly built biogas digesters should be filled with water for pressure testing to increase the air pressure to 2940 Pa. If the pressure drop within 24 hours is less than 10%, it can be considered that the sealing of the pool meets the requirements. Otherwise, sealing measures will be taken again and the above method will be used for inspection until it is qualified. All pipelines and valves that are compatible with biogas digesters must be inspected according to their respective operating technical conditions and design standards. For various pressure gauges and flow meters, as well as indicators and instruments for liquid level, temperature, pH, heaters, mixers, motors, water pumps, and other equipment, single machine debugging and overall system linkage operation shall be carried out according to their respective product quality inspection standards and design requirements, so that the entire set of equipment is in normal technical condition according to the process requirements.

　　沼氣發(fā)酵裝置的起動(dòng)

　　Start up of biogas fermentation device

　　沼氣發(fā)酵起動(dòng)期較長(zhǎng)，若能在起動(dòng)時(shí)加入大量厭氧活性污泥作為接種物就可縮短起動(dòng)期。起動(dòng)的生化需氧量負(fù)荷一般可在0.5～3千克COD/米3·天，待工作正常后可逐漸增加負(fù)荷，每次提高0.5～1.5千克COD/米3·天，每次提高負(fù)荷后的穩(wěn)定運(yùn)行時(shí)間為水力滯留期的5～10倍。在接種來源方便的地方，應(yīng)一次把所需的污泥加足。起動(dòng)運(yùn)轉(zhuǎn)階段注意因超負(fù)荷運(yùn)轉(zhuǎn)而出現(xiàn)酸化，使甲烷化過程受到抑制。

　　The start-up period of biogas fermentation is relatively long. If a large amount of anaerobic activated sludge can be added as inoculum during start-up, the start-up period can be shortened. The starting biochemical oxygen demand load can generally be between 0.5-3 kg COD/m3 · day. After normal operation, the load can be gradually increased by 0.5-1.5 kg COD/m3 · day each time. The stable operation time after each increase in load is 5-10 times that of the hydraulic retention period. In places where vaccination sources are convenient, the required amount of sludge should be added at once. During the start-up phase, attention should be paid to the occurrence of acidification due to overload operation, which can suppress the methane conversion process.

　　沼氣發(fā)酵工藝的生產(chǎn)控制

　　Production Control of Biogas Fermentation Process

　　沼氣發(fā)酵起動(dòng)后，主要通過調(diào)節(jié)所投加原料的量控制負(fù)荷，并控制溫度和發(fā)酵液的pH值等以保證正常的生產(chǎn)過程。在實(shí)際工作中，對(duì)進(jìn)料量、進(jìn)料和出料的COD或濃度、產(chǎn)氣量、氣體成分，進(jìn)出料的pH值及揮發(fā)酸含量進(jìn)行監(jiān)測(cè)。對(duì)于高濃度廢料的處理，如僅測(cè)定出水的pH值，會(huì)出現(xiàn)滯后現(xiàn)象，而應(yīng)在進(jìn)料端設(shè)置取樣點(diǎn)，當(dāng)發(fā)現(xiàn)pH值出現(xiàn)較大變化時(shí)立即減少或停止進(jìn)料，使pH值得到恢復(fù)，維持pH值在6.8以上，使沼氣池正常運(yùn)轉(zhuǎn)。沼氣產(chǎn)量也是很敏感的指標(biāo)，在工藝條件穩(wěn)定的情況下，沼氣產(chǎn)量大幅度上升，可能與負(fù)荷突然提高有關(guān)，此時(shí)須注意酸化現(xiàn)象的產(chǎn)生：如果負(fù)荷未變，氣體產(chǎn)量突然降低，此時(shí)須檢查是否有有毒物質(zhì)進(jìn)入沼氣池內(nèi)。氣體中的甲烷含量及發(fā)酵液中的揮發(fā)酸構(gòu)成也可以預(yù)報(bào)可能發(fā)生的事故。在一般情況下，甲烷含量均在55%以上，揮發(fā)酸中的乙酸占95%，丙酸占5%，丁酸和戊酸則含量甚微。如果甲烷含量下降，丁酸和戊酸含量上升，這就預(yù)示設(shè)備超負(fù)荷運(yùn)轉(zhuǎn)，須立即采取措施防止事故發(fā)生。在日常運(yùn)行過程中，注意定時(shí)打開排泥管排泥，放掉冷凝水收集器中的積水，排泥管長(zhǎng)期不排泥會(huì)因沉砂游積而堵死，冷凝水過多會(huì)引起輸氣管路堵塞。

　　After the start of biogas fermentation, the load is mainly controlled by adjusting the amount of raw materials added, and the temperature and pH value of the fermentation broth are controlled to ensure the normal production process. In practical work, monitoring the feed rate, COD or concentration of feed and discharge, gas production, gas composition, pH value of feed and discharge, and volatile acid content. For the treatment of high concentration waste, if only the pH value of the effluent is measured, hysteresis may occur. Therefore, a sampling point should be set up at the feeding end. When a significant change in pH value is found, the feeding should be immediately reduced or stopped to restore the pH value and maintain it above 6.8, so that the biogas digester can operate normally. Biogas production is also a sensitive indicator. Under stable process conditions, a significant increase in biogas production may be related to a sudden increase in load. At this time, attention should be paid to the occurrence of acidification phenomenon: if the load remains unchanged and the gas production suddenly decreases, it is necessary to check whether there are toxic substances entering the biogas digester. The methane content in the gas and the composition of volatile acids in the fermentation broth can also predict possible accidents. In general, methane content is above 55%, acetic acid accounts for 95% of volatile acids, propionic acid accounts for 5%, and butyric acid and valeric acid have very low content. If the methane content decreases and the butyric acid and valeric acid content increases, it indicates that the equipment is operating at overload and immediate measures must be taken to prevent accidents from occurring. During daily operation, pay attention to opening the sludge discharge pipe regularly to drain the accumulated water in the condensate collector. If the sludge discharge pipe is not discharged for a long time, it will be blocked due to sedimentation and accumulation. Excessive condensate water can cause blockages in the gas pipeline.

　　全混消化工藝和厭氧接觸工藝在運(yùn)轉(zhuǎn)過程中要對(duì)發(fā)酵原料進(jìn)行攪拌，通過攪拌可以增加原料和微生物的接觸，從而使反應(yīng)速度加快，同時(shí)可防止沉淀分層現(xiàn)象，保持池內(nèi)溫度均勻，防止產(chǎn)生或破壞浮渣層，促進(jìn)氣泡的分離和逸出。攪拌的次數(shù)與強(qiáng)度可根據(jù)具體情況確定，懸浮固體含量濃度大的發(fā)酵原料需加強(qiáng)攪拌，一般每天攪拌1～3次，每次攪拌的時(shí)間長(zhǎng)短以發(fā)酵原料達(dá)到完全混合的均一狀態(tài)為準(zhǔn)。過多的攪拌對(duì)發(fā)酵則不起作用。

　　The fully mixed digestion process and anaerobic contact process require stirring of the fermentation raw materials during operation. By stirring, the contact between the raw materials and microorganisms can be increased, thereby accelerating the reaction rate. At the same time, it can prevent sedimentation and stratification, maintain uniform temperature in the tank, prevent the formation or damage of the floating slag layer, and promote the separation and escape of bubbles. The frequency and intensity of stirring can be determined according to specific situations. Fermentation materials with high suspended solid content concentration need to be stirred more frequently, generally 1-3 times a day. The length of each stirring time is based on the fermentation materials reaching a completely mixed and uniform state. Excessive stirring has no effect on fermentation.

　　沼氣發(fā)酵過程中需保持溫度穩(wěn)定，因微生物對(duì)溫度有較大的敏感性，溫度變化將影響產(chǎn)氣量。對(duì)采用高中溫發(fā)酵的沼氣工程，溫度變化宜控制在±3℃之內(nèi)。

　　During the process of biogas fermentation, it is necessary to maintain temperature stability, as microorganisms are highly sensitive to temperature, and temperature changes will affect gas production. For biogas projects that use high and medium temperature fermentation, temperature changes should be controlled within ± 3 ℃.

　　沼氣裝置維修

　　Maintenance of biogas plant

　　分別制定所有沼氣裝置的檢修周期，除臨時(shí)維修外，按規(guī)定周期主要進(jìn)行檢修。發(fā)酵池每隔5～15年有計(jì)劃地清掃檢修一次，事先備好存放活性污泥的容器，以便檢修后很快投產(chǎn)。檢修時(shí)將污水、污泥浮渣和底部沉沙清掃干凈，進(jìn)行防腐、防滲、防漏處理，最后按規(guī)定進(jìn)行合格驗(yàn)收后，才能重新投入污泥繼續(xù)運(yùn)行。

　　Develop maintenance cycles for all biogas plants separately, and except for temporary maintenance, mainly carry out maintenance according to the prescribed cycle. The fermentation tank should be cleaned and maintained in a planned manner every 5 to 15 years, and containers for storing activated sludge should be prepared in advance for quick production after maintenance. During maintenance, the sewage, sludge scum, and bottom sediment should be cleaned up, and anti-corrosion, anti-seepage, and leak proof treatment should be carried out. After passing the qualified acceptance according to regulations, the sludge can be put back into operation again.

　　脫硫劑需定時(shí)進(jìn)行再生處理，當(dāng)脫硫裝置出口的沼氣中硫化氫濃度超過要求指標(biāo)，而脫硫劑的硫容尚未達(dá)到30%時(shí)，則需在裝置內(nèi)進(jìn)行脫硫劑的再生處理。再生時(shí)先將脫硫裝置沼氣系統(tǒng)關(guān)閉，前期可將上部的放空閥和塔底的排污閥打開，利用脫硫劑再生時(shí)本身放出的熱量形成空氣對(duì)流，再生即由下向上逐層進(jìn)行。后期用鼓風(fēng)機(jī)由上口向下鼓入空氣，直至進(jìn)出口氧濃度基本相等為止。再生時(shí)間一般在24小時(shí)左右。再生時(shí)切忌超溫，否則會(huì)導(dǎo)致硫升華和硫自燃，使脫硫劑失活，設(shè)備損壞。因此，再生時(shí)必須控制空氣流量，使脫硫劑床層溫度穩(wěn)定在60℃左右。脫硫劑的活性隨再生次數(shù)逐漸下降，一般使用2～5次即更換新的脫硫劑。

　　The desulfurizer needs to be regenerated regularly. When the concentration of hydrogen sulfide in the biogas at the outlet of the desulfurization device exceeds the required index and the sulfur capacity of the desulfurizer has not yet reached 30%, the desulfurizer needs to be regenerated inside the device. When regenerating, first turn off the biogas system of the desulfurization device. In the early stage, open the upper vent valve and the bottom drain valve of the tower, and use the heat released by the desulfurizer during regeneration to form air convection. Regeneration is carried out layer by layer from bottom to top. In the later stage, use a blower to blow air downwards from the upper opening until the oxygen concentration at the inlet and outlet is basically equal. The regeneration time is usually around 24 hours. During regeneration, it is important to avoid overheating as it can cause sulfur sublimation and spontaneous combustion, leading to deactivation of the desulfurizer and equipment damage. Therefore, during regeneration, it is necessary to control the air flow rate to stabilize the temperature of the desulfurizer bed at around 60 ℃. The activity of desulfurizer gradually decreases with the number of regenerations, and it is generally replaced with a new desulfurizer after 2-5 uses.

　　沼氣生產(chǎn)管理

　　Biogas production management

　　沼氣是一種易燃易爆、窒息性氣體，在沼氣生產(chǎn)管理中宜注意以下方面：①在沼氣生產(chǎn)區(qū)、沼氣發(fā)電室等處，禁止放置易燃、易爆物品，嚴(yán)禁煙火，并須備有消防設(shè)備。用氣設(shè)備均有阻止回火裝置（防火器），并保持良好狀態(tài)。②發(fā)酵池、貯氣柜、沼氣管道、有關(guān)設(shè)備等整個(gè)系統(tǒng)，不允許漏氣，經(jīng)常檢查，如發(fā)現(xiàn)漏氣立即修理。③發(fā)酵池、貯氣柜、沼氣管道、有關(guān)設(shè)備等整個(gè)系統(tǒng)，須保持正壓，嚴(yán)禁形成負(fù)壓。發(fā)現(xiàn)沼氣壓力比規(guī)定值下降時(shí)，立即采取措施，關(guān)小或停止用氣。④沼氣生產(chǎn)區(qū)、貯存區(qū)內(nèi)的電機(jī)，一律使用防爆電機(jī)，設(shè)備、管道有接地裝置，接地電阻不大于10歐。⑤多余沼氣導(dǎo)至鍋爐或安全區(qū)燃燒掉，必要時(shí)設(shè)置放空火炬。⑥發(fā)酵池的貯氣部分密封良好，同時(shí)裝放空口壓力計(jì)及壓力保險(xiǎn)裝置。防止因管路堵塞時(shí)造成池內(nèi)高壓，引起池體爆裂。⑦設(shè)有沼氣儀表的控制間須配備通風(fēng)機(jī)，每小時(shí)換氣8～12次。室內(nèi)不得設(shè)有易于發(fā)熱和產(chǎn)生火花的照明與電力開關(guān)設(shè)備，如設(shè)置時(shí)需加防爆措施。電線不準(zhǔn)裸露，通風(fēng)的電動(dòng)機(jī)應(yīng)外移或密封。⑧設(shè)專人負(fù)責(zé)安全生產(chǎn)，建立生產(chǎn)操作和使用沼氣的安全規(guī)章制度。⑨當(dāng)發(fā)生沼氣中毒時(shí)，立即將中毒者抬放至空氣流通處，盡快通知醫(yī)務(wù)人員救護(hù)。⑩發(fā)酵池檢修時(shí)必須打開所有的孔口，用鼓風(fēng)機(jī)連續(xù)吹入空氣24小時(shí)以上，經(jīng)動(dòng)物實(shí)驗(yàn)確實(shí)安全后方可進(jìn)入操作。檢修人員系上安全帶，池外有人監(jiān)護(hù)，整個(gè)檢修期間不得停止通風(fēng)。池內(nèi)所有照明和工具必須防爆。如需明火作業(yè)須符合公安部門的防火要求，同時(shí)備有應(yīng)急措施。用可燃性氣體監(jiān)測(cè)器，以保證人身絕對(duì)安全。

　　Biogas is a flammable, explosive, and suffocating gas. In the management of biogas production, attention should be paid to the following aspects: ① Flammable and explosive materials are prohibited from being placed in biogas production areas, biogas power generation rooms, etc. Smoking is strictly prohibited, and fire-fighting equipment must be prepared. All gas equipment is equipped with anti backfire devices (fire extinguishers) and maintained in good condition. ② The entire system, including fermentation tanks, gas storage tanks, biogas pipelines, and related equipment, must not leak air and should be regularly inspected. If any leaks are found, they should be repaired immediately. ③ The entire system, including fermentation tanks, gas storage tanks, biogas pipelines, and related equipment, must maintain positive pressure and it is strictly prohibited to form negative pressure. When the pressure of biogas drops below the specified value, immediate measures should be taken to reduce or stop using gas. ④ All motors in the biogas production and storage areas shall use explosion-proof motors, and the equipment and pipelines shall have grounding devices with a grounding resistance not exceeding 10 ohms. ⑤ Excess biogas is directed to the boiler or safe area for combustion, and if necessary, a vent flare is installed. ⑥ The gas storage part of the fermentation tank is well sealed and equipped with a vent pressure gauge and pressure safety device. Prevent high pressure in the pool caused by pipeline blockage, which may cause the pool to burst. ⑦ The control room equipped with biogas instruments must be equipped with ventilation fans, with 8-12 air changes per hour. Indoor lighting and power switch equipment that are prone to heat generation and spark generation shall not be installed, and explosion-proof measures shall be taken when installing them. Wires must not be exposed, and ventilated motors should be moved outward or sealed. ⑧ Assign a dedicated person to be responsible for safety production, establish safety rules and regulations for production operations and the use of biogas. ⑨ When biogas poisoning occurs, immediately lift the poisoned person to a well ventilated area and notify medical personnel for rescue as soon as possible. ⑩ During the maintenance of the fermentation tank, all openings must be opened and air must be continuously blown in for at least 24 hours using a blower. Only after animal experiments have confirmed safety can the operation be carried out. The maintenance personnel must wear safety belts and have someone outside the pool to supervise. Ventilation must not be stopped throughout the entire maintenance period. All lighting and tools in the pool must be explosion-proof. If open flame work is required, it must comply with the fire prevention requirements of the public security department and be equipped with emergency measures. Use a combustible gas monitor to ensure absolute personal safety.