沼氣發電機組氣源系統故障診斷全記錄：從甲烷含量到管路氣密性的深度解析

　　Full record of fault diagnosis of gas source system for biogas generator set: in-depth analysis from methane content to pipeline airtightness

　　在沼氣發電系統的日常運行中，偶爾會遇到這樣一種令人困惑的情況：黑膜沼氣池內的沼氣儲量充足，壓力表顯示正常，但與之相連的沼氣發電機組卻無法啟動或運行。面對這種 “有氣無用” 的困境，技術人員的首要任務就是進行系統性的故障排查。根據大量實踐經驗，此類問題的根源絕大多數指向氣源系統，具體可歸納為三大類：甲烷含量不達標、沼氣管路堵塞以及管路氣密性失效。本文將對這三類故障的診斷方法進行詳細解析。

　　In the daily operation of biogas power generation systems, there is occasionally a confusing situation where the biogas storage in the black film biogas digester is sufficient and the pressure gauge displays normally, but the connected biogas generator set cannot start or operate. Faced with the dilemma of 'having energy but no use', the primary task of technicians is to conduct systematic troubleshooting. Based on extensive practical experience, the root cause of such problems mostly lies in the gas source system, which can be classified into three categories: inadequate methane content, blockage of biogas pipelines, and failure of pipeline airtightness. This article will provide a detailed analysis of the diagnostic methods for these three types of faults.

　　一、甲烷含量不足：燃燒的 “能量源” 不夠

　　1、 Insufficient methane content: insufficient energy source for combustion

　　沼氣發電機組的啟動和穩定運行，依賴于沼氣中甲烷（CH?）的含量維持在一個特定范圍內，通常要求在 50% 以上。如果甲烷含量過低，即使沼氣量再大，也無法滿足發動機的點火和做功需求。

　　The start-up and stable operation of biogas generators rely on maintaining a specific range of methane (CH4) content in the biogas, usually requiring at least 50%. If the methane content is too low, even if the amount of biogas is large, it cannot meet the ignition and power requirements of the engine.

　　排查方法：最直接有效的方式是使用便攜式氣體分析儀，對進入發動機前的沼氣進行實時成分檢測。如果檢測結果顯示甲烷含量低于標準值，則需要追溯至沼氣池的發酵工藝。可能的原因包括：發酵原料的碳氮比失衡、發酵溫度過低導致產甲烷菌活性不足、或者發酵池出現酸化現象，抑制了甲烷的產生。解決此類問題需要調整進料配方、改善發酵環境或對發酵池進行必要的維護。

　　Troubleshooting method: The most direct and effective way is to use a portable gas analyzer to perform real-time component detection on the biogas before entering the engine. If the test results show that the methane content is lower than the standard value, it is necessary to trace back to the fermentation process of the biogas digester. Possible reasons include: an imbalance in the carbon to nitrogen ratio of the fermentation raw materials, insufficient activity of methane producing bacteria due to low fermentation temperature, or acidification in the fermentation tank, which inhibits methane production. To solve such problems, it is necessary to adjust the feed formula, improve the fermentation environment, or perform necessary maintenance on the fermentation tank.

　　二、沼氣管路堵塞：氣體流通的 “腸梗阻”

　　2、 Blockage of biogas pipeline: "intestinal obstruction" of gas circulation

　　從沼氣池到發動機的輸送管路，如同人體的血管，一旦發生堵塞，沼氣便無法順暢到達。堵塞物可能是發酵過程中產生的冷凝水、污泥雜質，或是管路安裝時殘留的異物。

　　The pipeline from the biogas digester to the engine, like the blood vessels of the human body, once blocked, the biogas cannot reach smoothly. Blockages may be condensation water, sludge impurities generated during the fermentation process, or foreign objects remaining during pipeline installation.

　　排查方法：首先檢查管路中的各個閥門是否處于全開狀態。隨后，觀察管路中的壓力表讀數，若在開啟閥門后，壓力表數值沒有變化或變化小，說明管路可能存在堵塞。技術人員需要分段檢查管路，排查彎頭、閥門、過濾器等易產生堵塞的部位。可以通過拆卸管路分段吹氣，或使用高壓氣體反向吹掃的方式，清除堵塞物。安裝的沼氣過濾器，并定期清理，是預防此類故障的關鍵。

　　Troubleshooting method: First, check if all valves in the pipeline are fully open. Subsequently, observe the pressure gauge reading in the pipeline. If there is no or minimal change in the pressure gauge value after opening the valve, it indicates that there may be a blockage in the pipeline. Technicians need to inspect the pipeline in sections, with a focus on identifying areas such as bends, valves, and filters that are prone to blockage. Blockages can be removed by disassembling the pipeline and blowing air in sections, or by using high-pressure gas to blow in the opposite direction. Installing efficient biogas filters and regularly cleaning them are key to preventing such malfunctions.

　　三、管路氣密性失效：系統的 “隱形漏洞”

　　3、 Pipeline airtightness failure: the "hidden loophole" of the system

　　如果說堵塞是 “不通”，那么氣密性失效就是 “漏氣”。沼氣管路在運行過程中，可能因接口松動、管道老化開裂或安裝不當等原因出現破損。當管路內部形成負壓時，外界的空氣會被吸入，與沼氣混合。

　　If blockage is considered 'not accessible', then the failure of airtightness is referred to as' air leakage '. During the operation of biogas pipelines, damage may occur due to loose interfaces, aging and cracking of pipelines, or improper installation. When negative pressure is formed inside the pipeline, external air will be sucked in and mixed with biogas.

　　排查方法：空氣的進入會稀釋沼氣中的甲烷濃度，破壞其空燃比，導致發動機無法點燃。檢查氣密性的方法包括：對整個管路系統進行壓力測試，觀察壓力是否能穩定保持；或在管路的各個接口、焊縫處涂抹肥皂水，若有氣泡產生，即表明存在泄漏點。對于發現的泄漏點，需要及時進行緊固或更換部件處理，確保整個氣源系統的密閉性。

　　Troubleshooting method: The entry of air will dilute the methane concentration in biogas, disrupt its air-fuel ratio, and cause the engine to fail to ignite. The method of checking air tightness includes: conducting pressure tests on the entire pipeline system to observe whether the pressure can be stably maintained; Or apply soapy water to various interfaces and welds of the pipeline. If bubbles are generated, it indicates the presence of leakage points. For discovered leakage points, it is necessary to promptly tighten or replace components to ensure the airtightness of the entire gas source system.

　　綜上所述，當沼氣發電機組出現 “有氣不工作” 的故障時，技術人員應遵循 “先易后難、分段排查” 的原則，從甲烷含量、管路堵塞和管路氣密性這三個核心環節入手，逐一進行檢測和排除。通過科學、細致的診斷，不僅能快速解決當前問題，更能為系統的長期穩定運行提供保障。

　　In summary, when a biogas generator unit experiences a malfunction of "not working with gas", technicians should follow the principle of "easy first, difficult later, and segmented troubleshooting", starting from the three core links of methane content, pipeline blockage, and pipeline airtightness, and conducting testing and elimination one by one. Through scientific and meticulous diagnosis, not only can current problems be quickly solved, but it can also provide guarantees for the long-term stable operation of the system.