On March 15, the State Mine Safety Supervision Bureau issued the "Notice on Further Strengthening the Safety Management of Coal Bunkers."

It points out that coal mines should strictly follow the requirements of relevant design specifications and carry out reasonable design based on the characteristics of surrounding rocks, coal bunker capacity, etc., from the shape of the coal bunker, masonry methods and material use, storage wall buffer devices and wear-resistant anti-hanging wall materials application, Carry out engineering design innovation in aspects such as reserving coal bunker water discharge holes, preset cleaning and dredging devices, etc. to enhance the coal bunker's ability to prevent blocking and collapse. Accelerate the research and development and application of unmanned warehouse exploration, clearance, and dredging technical equipment. Accelerate the development and application of robots in daily inspection, cleaning, blocking and dredging of coal bunkers, implement mechanized and robotic transformation, and realize unmanned operations as soon as possible.

following is the original text

Notice of the National Mine Safety Supervision Bureau on Further Strengthening the Safety Management of Coal Bunkers 矿安〔2024〕10号

Coal mine safety supervision departments of all provinces, autonomous regions and Xinjiang Production and Construction Corps, provincial bureaus of the State Mine Safety Supervision Bureau, and relevant central enterprises:

In order to thoroughly implement the spirit of General Secretary Xi Jinping's important instructions on production safety, deeply absorb lessons from accidents, and effectively strengthen the safety management of coal bunkers (including coal chute holes, coal chute holes, and waste silo, hereinafter collectively referred to as coal bunker), relevant matters are hereby notified as follows:

1. Compacting coal mine safety responsibilities

(1) Strictly implement the safety responsibilities of coal mine leaders and relevant departments. Coal mines should clarify the leaders in charge of coal bunker safety management and specific lead management departments, clarify the safety responsibilities of electromechanical management, production technology, safety management, communication prevention, dispatching and other departments, and clarify the safety management responsibilities and responsible persons of the specific user unit of each coal bunker.

(2) Improve and improve relevant systems. Coal mines shall establish and improve coal bunker management systems, including design, construction, safety management, daily inspection, overhaul and maintenance, risk identification, hidden danger investigation, emergency response, supervision and inspection, prevention of blockages and breakdowns, shutdown and reuse management, etc., and Conduct safety inspections regularly.

2. Accelerate the design optimization and mechanized transformation of coal bunkers

(1) Innovate warehouse design. Coal mines should strictly follow the requirements of relevant design specifications and carry out reasonable design based on the characteristics of surrounding rocks, coal bunker capacity, etc., from the shape of the coal bunker, masonry methods and material use, the application of silo wall buffer devices and wear-resistant anti-hanging wall materials, and reserve coal bunker drainage holes, preset cleaning and dredging devices, etc. Carry out engineering design innovation to enhance the ability of coal bunkers to prevent clogging and collapse.

(2) Improve the warehousing system and equipment. It is strictly prohibited to place the coal discharge chamber or operation table directly at the lower entrance of the coal bunker. A sufficient safe distance should be maintained between the two or reliable isolation measures should be taken. The coal discharge chamber or operation table should be arranged in the inclined tunnel upward direction of the tunnel. Promote the application of anti-collapse silo gates and other devices in the coal feeding system. Accelerate the implementation of remote control and transformation of the coal feeder at the bottom of the coal bunker to achieve unmanned duty.

(3) Accelerate the research and development and application of unmanned warehouse exploration, clearance, and dredging technical equipment. Accelerate the development and application of robots in daily inspection, cleaning, blocking and dredging of coal bunkers, implement mechanized and robotic transformation, and realize unmanned operations as soon as possible.

3. Strengthen coal bunker construction management

(1) Strengthen construction risk management and control. Coal mines should select professional teams with strong safety management capabilities and rich construction experience. Before construction, risk analysis and assessment should be carried out on hazardous factors such as falling from high altitude, equipment instability, and toxic and harmful gases, special operating procedures should be prepared, and strict safety technical measures should be formulated.

(2) Strengthen supervision of the construction process. It is necessary to urge the construction unit to strictly follow the coal bunker construction operation procedures. When using a reverse well drilling rig to dig coal bunkers, it is strictly prohibited for people to stay, pass, observe or remove slag below during the reaming operation. Clean up the waste rock in the waste rock slide hole in time to prevent hole clogging. Special measures must be formulated to deal with blockages. It is strictly prohibited to stand on the waste rock in the waste rock slide hole.

4. Strengthen daily management and maintenance

(1) Strengthen safety warnings and facility configuration. Obvious safety warning signs should be set up near the coal bunker to indicate the existing risks and control measures. Safety facilities such as preventing people and materials from falling must be installed at the upper entrance of the coal bunker.

(2) Strengthen monitoring and control. Monitoring instruments and equipment such as video, personnel proximity warning, infrared thermal imaging, CO sensors, CH4 sensors, and coal level meters should be installed around the coal bunker, and should be connected to the mine dispatch system to promptly alarm coal accumulation abnormalities and other situations.

(3) Strengthen the source and process control of coal flow. Coal mines should strengthen the identification and treatment of large coal gongs and foreign matter in the transportation system. Crushers should be installed at working face transfer machines and other places. Iron remover should be installed at the coal flow transportation system. Grates should be installed at the entrance of coal bunkers. Promote the application of video AI foreign matter identification and other technologies to prevent large coal gongs, iron, wood and other debris from entering the coal bunkers. If raw coal has a large water content, a coal-water separation device shall be installed in the main coal flow transportation system.

(4) Reasonably determine coal storage positions. The loading volume and empty volume of coal bunkers shall be controlled within the specified range. If the mine is suspended for maintenance for 24 hours or more, the position must be controlled at the lowest position, and emptying without construction tasks is strictly prohibited. When the coal bunker is not in use for a long time, it must be emptied and measures must be taken to prevent short circuit of wind and current.

(5) Strengthen the management of coal bunker shutdown and reuse. When coal bunkers are stopped for long-term reuse, the coal mine must organize on-site inspection and acceptance to confirm that safety conditions are met before it can be put into use. A release control process is formulated to control the water and gas accumulation in the coal bunkers, water coal and coal storage positions, coal flow. Conduct a comprehensive investigation of mechanical and electrical equipment along the line to ensure safety before releasing the warehouse.

(6) Do a good job in waterproofing coal bunkers. It is strictly forbidden to use the coal bunker as a water channel, and the upper mouth of the coal bunker should be higher than the floor of the roadway. If raw coal has a large water content, measures such as interception and drainage should be taken by drilling holes at the lower entrance of the coal bunker. When water is sprayed in the coal bunker, measures such as blocking, draining, and drainage must be taken, and it shall not be used unless it is properly handled.

(7) Strengthen the maintenance and management of coal bunker facilities and equipment. Regularly check the integrity of equipment and facilities, standardize testing and testing, strengthen maintenance and repair in a timely manner. Special safety technical measures must be formulated for the maintenance, cleaning, repair and reinforcement of coal bunkers, and the work must be carried out from top to bottom. Imaging scanners, cameras and other equipment should be used for exploration to prevent people from entering the coal bunker. If it really needs to be put into warehouses for treatment, special safety technical measures should be formulated and strictly implemented. Safety monitoring personnel must be equipped on site to strictly prevent accidents such as falling, coal gangue collapse, suffocation, poisoning, and falling into slime. When repairing the coal feeder at the lower entrance of the coal bunker, a warning should be set up at the upper entrance of the coal bunker to prevent coal flow and debris from entering the coal bunker, and emergency measures should be taken to prevent wind and current short circuit.

5. Strengthen on-site disposal

(1) Strengthen safety risk management and control. When handling situations such as blockages and collapses on site, it is strictly prohibited to deal with them blindly without authorization. Mine leaders shall organize on-site surveys, study and formulate safety technical measures, and only construction can be carried out after approval from the mine manager; during on-site disposal operations, mine leaders must supervise and guide on site, and equip them with safety guardians and strictly control the number of people working on site.

(2) Standardize the blockages disposal process. When dealing with blockages, priority should be given to using air cannons, ultrasound, fixed mechanical devices, etc. for dredging. If it is really necessary for personnel to enter the warehouse for handling, it is strictly prohibited to enter from below. Personnel must wear seat belts throughout the entire process, and the seat belts have reliable fixing points to strictly prevent negative pressure formed when the coal bunker is dredged and people are involved. When blasting treatment is necessary, the relevant provisions of the "Coal Mine Safety Regulations" shall be strictly implemented.

(3) Standardize the warehouse collapse disposal process. When dealing with a silo collapse, the operating procedures of the coal feeder gate and the responsibilities of on-site safety monitoring personnel must be clarified, the observation of the water and coal bin in the coal bunker and the coal feeder gate must be strengthened, and a warning line must be set up in the construction area to prevent other personnel from entering the bunker by mistake, so as to ensure that construction personnel stand safe and the operation of the coal feeder gate must be standardized to strictly prevent secondary silo collapse accidents.

6. Strict supervision and inspection

Strengthen safety supervision and inspection of coal bunkers. Coal mine safety supervision and supervision departments must strictly enforce the law, urge coal mines to implement coal bunker safety management responsibilities, comprehensively investigate and control hidden dangers, resolutely crack down on illegal operations in coal bunkers, and strictly prevent all types of coal bunker accidents.

All provincial coal mine safety supervision departments are requested to immediately forward this notice to all coal mines in their jurisdiction and continue to supervise its implementation. At the same time, it is necessary to urge all coal mines in the jurisdiction to formulate and strictly implement a timetable and roadmap for the mechanization and automation of coal bunker entrances.

National Mine Safety Supervision Bureau March 14, 2024