Solution of gas detection system in municipal pipe network and sewage treatment plant

Municipal pipe network and sewage treatment plant are “kidneys” and “blood vessels” of urban operation, but they are also “invisible killers” of high-risk gas collection. Hydrogen sulfide poisoning, methane explosion, limited space hypoxia and suffocation are common accidents in the industry. The traditional inspection mode of “people carrying instruments and holding notebooks” is completely out of date today in 2026. At present, the core of the solution is three words:global perception, intelligent linkage and unattended. This is not just a set of equipment, but a secure Internet of Things covering the ground and underground.

Let’s talk about the municipal pipe network first, which is the most difficult “blind spot”. The underground well is complex, the gas accumulates quickly, and the risk of manual underground detection is great. The latest solution is to build a trinity system of “fixed monitoring+mobile inspection+underground robot”. Install explosion-proof fixed gas monitoring terminals in key inspection wells and valve wells, focusing on monitoring hydrogen sulfide (H2S), methane (CH4) and oxygen (O2). These terminals are no longer isolated. They directly transmit data to the cloud through low-power WAN technologies such as NB-IoT or LoRa. Once the concentration of underground hydrogen sulfide exceeds the standard, the system will not only send an audible and visual alarm on the spot, but also immediately push the alarm to the mobile phone APP of the person in charge of the area, and even link the electronic lock of the nearby manhole cover to prevent irrelevant personnel from opening it by mistake. For pipeline sections that are difficult to reach manually or with high risk, pipeline inspection robots are popular now. They are equipped with high-sensitivity laser methane detectors and panoramic cameras, which crawl in the pipeline like “robot dogs” and send back the video stream of gas concentration in real time, completely liberating people from the dangerous environment. In addition, the portable detector equipped by inspection personnel must also be upgraded and have the function of “near field communication”. When it is close to the monitoring well, it can automatically read the data in the well and know whether it is safe below without opening the cover. This is the real life-saving technology.

Look at the sewage treatment plant, which is the “hardest hit” by gas hazards. Hydrogen sulfide, ammonia, methane and volatile organic compounds are everywhere, from the intake pump room to the grille room, from the biochemical pool to the sludge dewatering workshop. The traditional solution is to hang fixed detectors everywhere, but there are often dead corners and the false alarm rate is high. The mainstream scheme in 2026 is “grid precise monitoring+process linkage control”. In high-risk areas (such as the bottom of pump house and above sludge pool), multi-point array gas sensors are deployed to form an invisible monitoring network. Using airflow model algorithm, we can not only measure the concentration, but also infer the specific location of leakage source from multi-point data. The more advanced system will be directly connected with the PLC (programmable logic controller) of the factory: once the combustible gas leakage is detected, the system will automatically start the forced exhaust fan; If the hydrogen sulfide exceeds the standard, the relevant water inlet valve will be automatically closed, and the spray dilution device will be started, so that the accident will be eliminated in the bud without manual intervention. In order to solve the problem of odor disturbing people at the factory boundary, the on-line odor monitoring system has been widely used, and the high-sensitivity electronic nose technology is used to monitor the odor concentration of unorganized emission at the factory boundary in real time. The data is directly connected to the platform of the Environmental Protection Bureau, which not only avoids residents’ complaints, but also meets the compliance requirements.

The “brain” of this system is the smart security management cloud platform. It is no longer a simple data display screen, but a decision center with AI analysis ability. The platform can accumulate massive historical data and analyze the changing law of gas concentration through machine learning. For example, it can be predicted that “at the beginning of rainy season, the concentration of hydrogen sulfide in a pipe network in a certain area will easily soar”, so as to give an early warning and guide the operation and maintenance personnel to carry out targeted dredging. It can also manage the life cycle of all devices. When the sensor is about to expire, the battery is insufficient and needs to be calibrated, the system will automatically generate a work order and distribute it to the maintenance personnel.