2.5MPa, and the rated evaporation is greater than or equal to 10 t/h, then it is a major source of danger. General power plant host boiler, are in line with the standards of major sources of danger. The new construction project has a fuel-fired start-up boiler, used to provide unit start-up deaerator, warm air heater, fuel atomization, auxiliary steam and other steam, generally intermittent use of 3 to 5 years time. Some meet this standard, some do not meet this standard, need to be determined according to the actual situation of the project. For example, the 2×500MW imported supercritical unit of Panshan Power Plant is installed with four 50t/h imported start-up boilers with steam pressure of 3.9MPa and temperature of 440℃, which is a major source of danger. The 150MW class unit of the start-up boiler, general steam parameters pressure 1.25MPa, temperature 300 ~ 350 ℃, capacity of 10t / h or so, is not a major source of danger. March 10, 1993, Ningbo City, Zhejiang Province, Beilun Harbor Power Plant Unit 1 occurred in a large boiler furnace explosion, resulting in 23 deaths, 8 serious injuries, injuries to 16. September 23, 2004, Xinxing Casting Pipe Co., a power plant project under construction gas boiler explosion occurred, resulting in 13 deaths, 8 people were injured. 2.2 Identification of major sources of danger in ignition light diesel oil irrigation area The light diesel oil used for boiler ignition is not in the GBl8218-2000 "Light Diesel Oil for Boiler Ignition and Combustion" because of its high flash point ("GB252-2000" modifies the flash point index of the light diesel oil of No.10, No.5, No.0, No.-10, and No.-20 grades to ≥55℃ from ≥65℃), not in the GBl8218-2000 "Light Diesel Oil for Boiler Ignition and Combustion" because of its high flash point. GBl8218-2000 "Identification of Major Hazardous Sources" in the list of flammable substances. However, according to Safety Supervision and Regulation Coordination Word [2004] No.56, flammable liquids such as kerosene, turpentine, butyl ether, etc., stored in storage tanks (storage tanks), constitute major sources of danger if the flash point of 28℃ ≤ 60℃, and the storage capacity is more than 100t. Ignition of light diesel oil flash point within this range, in the 2 × 135MW unit of the project, generally set up 2 × 500m3 storage tanks, in the 2 × 300MW unit of the project, then set up 2 × 1,000m3 storage tanks, in thermal power plants with large storage capacity, should be ignition of the oil tanks area is classified as a major source of danger management. May 13, 2005, Xinjiang Hongyanchi second power generation limited company plant tank explosion, followed by a fire, the accident was caused by the site construction workers violated the safety production operating procedures. The accident was caused by the violation of safe production operation procedures by the site construction workers. The explosion resulted in 5 deaths, 1 serious injury and heavy losses to the power plant. 2.3 Identification of major sources of danger of hydrogen storage tanks (group) In power plants where the generator is cooled by water-hydrogen-hydrogen, there is a hydrogen production station to provide hydrogen for cooling the generator windings and cores, and if the generator is air-cooled or double-water-cooled, there is no hydrogen production station. Hydrogen is a colorless and odorless gas with a density of 0.0899g/l, a boiling point of -252.8℃, a spontaneous combustion point of 572℃, and an explosion limit of 4.0%~74.4%. Hydrogen is inactive at room temperature, but flammable. Typical design of 300MW unit as an example, the general hydrogen production station hydrogen flow rate of Q = 10Nm3 / h, pressure 3.2MPa, 4 hydrogen storage tanks each volume V = 13.9m3. According to the safety supervision and coordination of the word [2004] No. 56, for acetylene, hydrogen, liquefied petroleum gases and other flammable gases, the explosion limit is less than 10%, if the storage volume in the storage tank area (storage tanks) more than 10t, it is a major source of danger. , is a major source of danger. Storage tanks in the storage of 3.2 MPa hydrogen 55.6m3, after conversion, the amount of hydrogen is calculated to be about 0.16t, is not a major source of danger. However, in the same document, it is stated that if the flammable medium stored in the pressure vessel (group) has a maximum working pressure ≥ 0.1 MPa and a PV ≥ 100 MPa x m3, it constitutes a major source of danger. Hydrogen storage tank 177.92 MPa×m3 ≥100 MPa×m3 in the power plant should be a major source of danger. Therefore, the hydrogen storage tank (group) should be classified as a major source of danger management. September 7, 1989 Tianjin Yangliuqing Power Plant hydrogen tank explosion. In the process of charging hydrogen to the No. 3 generator, due to the No. 1 hydrogen and oxygen side of the hydrogen equipment pressure regulator jamming, resulting in oxygen to hydrogen, so that the No. 1 hydrogen tank hydrogen, oxygen mixture to reach the explosion limit, in the shift personnel pouring cans to open the door instantly, because of the large pressure difference between the hydrogen (0.4MPa), the flow rate is fast (the initial flow rate of up to several hundred meters per second) disturbed rust friction heat, detonation of the No. 1 tank mixed gases, hydrogen tanks occur! explosion. 2.4 Identification of significant sources of risk in the ash storage yard
Coal-fired power plant production process constantly produces a large amount of ash. In order to prevent the ash discharged into the river caused by environmental pollution, new, expanded and rebuilt coal-fired power plants must be constructed at the same time the ash storage site, storage of coal-fired power plants discharged fly ash and slag. Power plant ash is generally harmless and less toxic three types of slag, in the design of the ash field, the need to analyze and test the ash and ash water trace heavy metal elements and other harmful substances in the content of the dust and ash water to prevent pollution of the river water discharge measures. According to the regulation of safety supervision and coordination of the word [2004] No. 56, the full capacity of ≥ 1 million m3 or the height of the dam ≥ 30 m tailing pond is a major source of danger. The ash storage site belongs to one kind of tailings storage, and the general storage capacity is large, such as 600MW installed capacity of the power plant discharges more than 30 × 104t of ash per year, the design capacity of the ash storage site is generally greater than 300 × 104 m3, and it should be managed as a major source of danger. In 1983, the Jingdezhen power plant ash field collapse dam, in 1985, Yushu River power plant ash field collapse dam, as well as the Tuxian power plant ash field collapse dam, Xishui power plant ash field collapse dam accident have caused serious losses, but also caused personal injury and death. Some power plants are located in more densely populated areas, and in the event of an ash-field dam collapse, the consequences will be unimaginable. In early June 2006, Guizhou Qiangui Power Generation Co., Ltd. and Jilin Yanbian Chenming Paper Co., Ltd. own thermal power plant occurred two power plant ash reservoir leakage accidents, resulting in large economic losses and environmental pollution. The State General Administration of Safety Supervision and the Electricity Regulatory Commission notified the incident with the document of Safety Supervision and Administration of General Administration of Safety Supervision No. 1 2006141, and made it clear that the ash slag depot is a type of tailing depot, which belongs to the source of major hazards, and it should be managed in accordance with the Provisions on Safety Supervision and Management of Tailings Dumps and the Regulations on the Safety and Technology of Tailings Dumps and the safety production license system of the ash slag depot should be strictly implemented. 3. Safety management of major sources of danger Article 33 of the Work Safety Law stipulates that production and operation units shall register and archive major sources of danger, carry out regular testing, assessment and monitoring, and formulate emergency plans to inform practitioners and relevant personnel of the emergency measures to be taken in case of emergency. Production and operation units shall, in accordance with the relevant provisions of the State, report their sources of major hazards and related safety and emergency measures to the departments of the relevant local people's governments responsible for the supervision and management of work safety and the relevant departments for the record. The Decision of the State Council on Further Strengthening Work Safety (Guo Fa 20042) calls for a better census and registration of major sources of danger, and the strengthening of the monitoring of major sources of danger at the national, provincial (autonomous regions and municipalities), municipal (local) and county (municipal) levels. The Notice on Further Strengthening and Standardizing the Supervision and Management of Major Dangerous Sources (An Supervision Division Office [2004] No. 127) requires that the leadership of the supervision and management of major dangerous sources be strengthened, the efforts of the work be further intensified, the technical guidance and policy guidance be strengthened, the supervision and inspection be intensified, and the advantages of the relevant intermediary organizations and scientific research units in terms of technological support and services be fully utilized to prompt production and operation units to To do a good job in monitoring and controlling major sources of danger. The Notice on Doing a Serious Job in the Supervision and Management of Major Dangerous Sources (Safety Supervision General Coordination Word [2005] No. 62) points out that enterprises are the main body of safety production and the main body of management and monitoring of major dangerous sources, and they have important responsibilities in the management and monitoring of major dangerous sources. All levels of production safety supervision and management departments should supervise and inspect and guide and urge enterprises to do a good job in the management of major sources of danger. The document puts forward to do a good job of registration and filing and declaration, to ensure financial investment, the establishment of sound rules and regulations and the implementation of responsibility, safety education and technical training, testing and inspection, hidden accidents and defects rectification, the development of emergency rescue plans, and continuously improve the monitoring and management tools and other ten specific requirements. 4. Preparation of Emergency Rescue Plans for Accidents A series of national laws, regulations and documents clearly stipulate that emergency rescue plans should be prepared for major sources of danger, and that technical training and accident drills should be carried out on a regular basis. Experts should be organized to identify, assess or evaluate the major sources of danger, and formulate the emergency rescue plan for the results of identification, assessment or evaluation, which is the basis and starting point for formulating the plan. Strict management system should be formulated for the identified major sources of danger, and the state and degree of loss in case of major accidents and the degree of harm that may be caused to the neighboring areas should be predicted. The basic requirements of the accident emergency rescue plan include: the implementation of accident prevention measures, the provisions of emergency treatment procedures and
methods, and the technical guarantee of rescue and relief. When writing or formulating the accident emergency rescue plan, it should specifically describe the measures to be taken when accidents and emergencies occur, and the basic requirements are: Specifically describe the possible accidents and emergencies and their consequences. Identify the person in charge during the emergency and the duties of all personnel during the emergency. Define the duties, authorities and obligations of personnel who play a special role during the emergency (e.g. firefighters, first aiders, hazardous situation disposal personnel). Define evacuation procedures. Define the identification and location of hazardous materials and emergency measures for their disposal. Establish contact with external emergency response agencies (fire departments, hospitals, etc.). Communicate regularly with the safety supervision and management authorities, public security departments, insurance agencies and neighboring companies. Protect important records and equipment, etc. (e.g., plant layout diagrams, hazardous material data, contact phone numbers, etc.).