Eight types of poisonous gases are rarely hidden in railway tunnels, and construction parties use gas detectors
Gas detectors ensure the construction safety of Hongdoushan Tunnel
It is understood that the more than 10,000-meter-long Hongdoushan Tunnel is an important part of the China-Myanmar International Railway, and it is also the most difficult control project in the construction of the Dalin Railway (Dali to Lincang) under construction in Yunnan.
In this tunnel, the dangerous area of toxic and harmful gas accounts for more than 70% of the whole tunnel. Toxic and harmful gases exist in non-coal formations, which is the first time in the history of China's railway construction.
There are as many as 8 kinds of toxic and harmful gases enriched in this tunnel, which have exceeded the cognitive level of geological exploration, and there is no mature technology available.
It is reported that this tunnel is the only poisonous gas tunnel that has collected 8 kinds of poisonous and harmful gases so far encountered in the construction of railways in my country. These gases include hydrogen sulfide, carbon monoxide, sulfur dioxide, nitrogen dioxide, and the like.
Among them, excessive carbon monoxide concentration can cause suffocation and explosion, nitrogen dioxide can damage the respiratory tract and cause pulmonary edema and other diseases, hydrogen sulfide can be fatal in a short time after inhalation...
Use of Toxic and Harmful Gas Detectors at Tunnel Construction Sites
▲A builder is working under the toxic and harmful gas monitor
In this regard, the project construction party cooperated with universities to carry out scientific and technological research on the key technologies for the construction of the non-coal series harmful gas section of the tunnel, and achieved innovative breakthroughs.
With the help of advanced gas sensor monitoring technology, multiple sets of harmful gas automatic monitoring and alarm devices and portable gas detectors are specially installed in the construction tunnel to detect and monitor harmful gases in advance, and monitor the air quality in the tunnel in real time.
Fixed Gas Detector
▲Fixed gas detector
Selection of Toxic and Hazardous Gas Detectors in Tunnels
Toxic and harmful gases in tunnels have always been the main source of danger during construction, and major safety accidents are likely to occur if construction is improper. In this regard, gas monitor equipment based on various gas sensor detection technologies comes in handy.
In industrial installations and production processes, fixed gas detectors are more commonly used.
The fixed gas detector is generally two-body type. The detection probe composed of gas sensor and transmitter is installed on the detection site as a whole, and the secondary instrument composed of circuit, power supply and display alarm device is installed in a safe place as a whole, which is convenient for monitoring. .
Portable Gas Detector
▲Portable gas detectors used in foreign tunnel corridors
For complex and harsh tunnel environments like Hongdoushan Tunnel, portable gas detectors are the best choice, especially multi-gas composite gas detection equipment, which can monitor a variety of toxic and harmful gases at the same time, adapting to various complex or harsh conditions. environment.
At the same time, through the built-in wireless communication module, wireless transmission can be realized in the area covered by wireless signals. When the gas concentration exceeds the standard, it will alarm immediately to ensure the safety of workers.
In the specific selection, because the harmful gas in the tunnel can be divided into two categories: combustible gas and toxic gas. Therefore, it is very important to choose a suitable gas detector for different production occasions and detection requirements.
For example, when choosing a gas detector, if there are mostly methane and other less toxic alkanes, it is the best choice to choose combustible gas sensor detection equipment;
However, if there are toxic gases such as carbon monoxide (CO) and hydrogen sulfide (H2S), specific gas detectors should be selected first; Choose a photoionization detector (PID);
If the above multiple types of gases are covered, choosing a composite gas detector will achieve twice the result with half the effort.
