Gas explosion accident emergency rescue and rescue

2.3 Adhere to people-oriented, safe rescue, implementation in place

When dealing with gas explosion accidents and disaster relief, in the face of the complex disaster environment and the existing technical conditions for disaster relief, we must respect the laws of disasters and correctly handle the relationship between disaster relief and personnel safety. In the event of conflict between the control and protection of disaster conditions and the protection of ambulance personnel and the rescue of persons in distress, we must implement the concept of “using people’s texts” to first ensure the safety of rescue workers and persons in distress. In any case, we must not neglect the safety of rescue workers and unilaterally pursue disaster relief. schedule. Ambulance commanders to strictly enforce the << coal mine safety regulations >> and << mine rescue procedures >> provisions, the courage to uphold the principle of wrong decisions and orders should have the courage to refuse, positive comments, the disaster relief program in line with the provisions of the ambulance and regulations, decisions and avoid Mistakes in command. Failure to do so may cause the accident to expand and increase casualties.

After the disaster relief plan and safety measures are established, the rescue personnel should speed up the rescue as soon as possible to ensure safety, follow the shortest route, reach the site where the most people in distress are located for investigation, and extinguish the fire caused by the explosion. Lifesaving access to rescue distressed persons. All rescue forces must strictly implement the decision-making of disaster relief headquarters, seek truth from facts, and have no omissions. At the same time, they must promptly and promptly report the actual situation of on-site rescue to the relief headquarters to ensure the smooth implementation of channels and command channels.

3 gas explosion accident treatment technical points

In the event of a gas explosion accident, it is necessary to quickly understand and master the accident situation and development status in a variety of ways in order to make preliminary judgments and quickly formulate scientific and effective disaster relief technical solutions.

3.1 Is the power cut off immediately

The industry has different views on whether or not to cut off the power immediately after a gas explosion occurs, because cutting off the power supply in the disaster area may generate electric sparks, which may cause secondary explosions and expand the scope of disaster destruction, but do not cut off the power supply in the disaster area, due to the original power supply system in the disaster area. If it is damaged, the route may be diverted, damaged, etc., which may cause electric shock hazards to trapped and rescue personnel in the disaster area. According to past rescue experience, whether or not to cut off the power supply in the disaster area must be judged according to the type of gas explosion. If it is a gas outburst explosion, there is still a large amount of gas in the roadway. In this case, it is not appropriate to cut off the power supply. The rescue team should strengthen their awareness of protection against electric shock. For a cumulative gas explosion, the gas emission rate is not fast and the volume is small. Usually, after the explosion, the residual gas gas concentration is low, and generally it will not cause secondary explosion. At this time, the power supply can be cut off to improve the safety of rescue work. .

3.2 Establishing ventilation conditions to exclude harmful gases from explosion

After the explosion, ventilation conditions should be established as far as possible to restore ventilation in the disaster area. On the one hand, harmful gases from gas explosions can be eliminated and the living environment of trapped people can be improved. On the other hand, oxygen can be added to the disaster area to maintain the survival needs of trapped people. . However, before establishing ventilating conditions to restore ventilation in the disaster-affected area, we must first determine whether the explosion caused a fire and whether the ventilation is safe. The basis for this is to judge according to the change of toxic and harmful gases such as the CO in the return air system in the disaster area; and through the investigation of the disaster area by the ambulance personnel. If it is determined that there is a fire in the disaster area, safety measures must be taken to extinguish the fire before ventilation. As for how to properly manage the ventilation system ( reverse wind, short circuit, enhanced ventilation, etc. ) , remove toxic and harmful gases in the disaster area as soon as possible, and control the scope of accidents to be expanded. This needs to be dealt with according to the specific conditions of the rescue site. In short, ventilation channels must be established quickly.

3.3 Rehabilitate the ventilation of the excavation roadway and establish a rescue channel

If the explosion occurs in the excavation roadway, a large amount of gas and harmful gases accumulate in it, and there may be a fire source or an electric explosion device. In order to safely and quickly restore the ventilation of the excavation roadway and find the victims, follow the conventional method. To restore the ventilation of the excavation roadway, there is still the risk of secondary explosion. To ensure safe rescue, the “one-time recovery, long-distance start-up” method can be adopted, that is, rescue workers wear a positive pressure oxygen respirator to pick up the wind tube in the disaster area and then evacuate. Go to a safe area, and then start long-distance ventilation, so that even if an explosion occurs, it will not harm the rescue workers. This method has been applied in the rescue of multiple gas explosion accidents and has achieved good results.

4 Disaster relief examples

2002 at 2:40 on September 10, Heshan District, Hebi City Heshan District Lu Village mine (township coal mines) gas explosion occurred, 13 people were killed.

Gas explosion process diagram of Figure 1 large Lu Village Coal Mine

According to the command of the headquarters, the ambulance team promptly went downhole to investigate. The investigation completed the following tasks:

(1) Extinguishes the burning of about 10 scaffoldings and fillings on the inlet ramp and the six Yokogawa fork to prevent the accident from expanding.

(2) The closed walls of the first to sixth Yokogawa Rivers in the entrances and exits to the wind have been destroyed by explosion blast waves. The inlet ramps and the Qiyumgawa River crossings have been capped and dead, and the return wind lanes and the six Yokogawa River crossings are each 2m All of them are at the top and inaccessible. The ventilation system is destroyed. There were no other open fires in the entrances to the return air, and no people in distress were found in the investigation areas.

(3) Incoming storm level 1 to 6: The concentration of CH4 in Yokogawa ranges from 1.5 % to 2.5 %, CO concentration from 0.0005 % to 0.03 %, and the concentration of O2 from 17 % to 19 %; the concentration of CH4 in return airways from 1 to 6 is 20 % . 60 %, CO concentration is 0.03 % ~ 0.5 %, O2 concentration is 10 % ~ 12 %; return air mouth wellhead CH4 concentration is 0.5 %, CO concentration is 0 %.

According to the analysis of the investigation, the headquarters determined that the miners in distress have no chance of surviving. In order to ensure safe relief and avoid accidents, measures must be taken to restore ventilation. The main process of its technical decision is:

(1) Restore the ventilation system and use full negative pressure ventilation to discharge the accumulated CH4 and CO in the disaster area . However, at the time of implementation, due to the incomplete information provided by the mine, the mining drawings were not standardized, there were many old lanes, there were many air leakages in the air intake roadway, and the main fan power was only 15kW , which did not reach the full negative pressure effect, and then the underground roadway was taken. Plugging and preventing air flow short-circuit measures, but still failed to achieve the purpose of restoring full-negative pressure ventilation, that is to give up this program.

(2) Adjusting the ventilation system To implement positive pressure ventilation, in order to speed up the discharge of harmful gases in the disaster area and rescue the victims, the headquarters decided to install a 2 × 15kW counter-rotating fan at the downhill platform to replace the 5.5kW fan at the bottom of the mountain . The cylinder directly injects fresh air into the air intake roadway to increase the air volume in the disaster area, and builds a temporary airtight seal in Yokogawa. The gas and harmful gases in the first to sixth Yokogawa Rivers of the air inlet and outlet airways are quickly discharged. 2m before the top of the entrance into the wind lane and the Qiyumgawa fork And 25m Two death victims were found at each location .

(3) In order to find other missing persons, the headquarters decided to restore the ventilation of the single coal mining lane in the upper part of the Yaskawa River as soon as possible. According to ambulance crew reconnaissance, the concentration of CH4 in the return roadway from the seventh to eighth Yokogawa and the upper one in the Yatagawa River was 80 % to 90 %, the CO concentration was 0 %, the O2 concentration was 2 % to 7 %, and the temperature was 35 °C . Considering that if there is a spark caused by the damage of the miner's lamp in the disaster area, if gradual recovery ventilation is adopted, the possibility of causing secondary explosions cannot be ruled out. In order to ensure safety, the headquarters decided to adopt a “one-time recovery, long-distance start-up” approach. The ambulance crew wears an oxygen respirator to connect the air duct from the lower mouth of San-Yokogawa to the upper part of Yaskawa. At the lower part of the San-Yokogawa River, the air receiver was connected to the original air cylinder, and all personnel were withdrawn to the second Hayama wind bridge, and a local fan was started remotely. On September 17th , four classes completely restored the ventilation of the single coal mining roadway in the upper part of the Yaskawa River and rescued seven victims. The last two victims in class at 8:00 on September 18 and at 0:19 on September Ri classes, respectively, into the wind on the right side of Road and River Crossings seven horizontal caving caving and was rescued the next object within eight Yokogawa. At this point, the rescue work was basically completed.

5 conclusions

(1) The correct implementation of gas explosion accident management principles is an important factor to ensure the safe and rapid handling of mine disaster accidents. At the same time, according to the mine disaster conditions, the gas explosion accident handling technology key points are correctly applied to effectively curb the occurrence of secondary disaster accidents.

(2) Combine the gas explosion accident handling principles and technical points, and formulate scientific and effective disaster relief plans and measures for the specific conditions of the disaster area, and strictly enforce them, which can ensure the safe and smooth progress of rescue and relief work and improve the efficiency of accident rescue.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.