Analysis and Countermeasures of safety accidents in open flame operation in petrochemical enterprises
petrochemical enterprises are currently developing in the direction of large-scale production devices. From the input of raw materials to the output of products, production needs to go through multiple processes and complex processing units, and the auxiliary heating, water supply, air supply and power supply system is huge. The furnaces, towers, tanks, tanks, compressors, pumps and other equipment used in the production process are connected by pipelines, thus forming a production line with complex process and long process flow. In the production process, each process is closely connected and mutually restricted, with a high degree of continuity; With the application of computer technology, control technology and communication technology, the degree of automation of production devices is becoming higher and higher. Especially in the petrochemical industry, the production process has many potential risk factors, such as high temperature, high pressure, flammable, explosive, toxic, harmful, corrosive, etc., and the safety production is becoming more and more difficult, especially in the production, emergency repair, overhaul process, hot work is inevitable. In the process of hot work, if a little preventive measures are not in place, it is prone to fire, explosion, poisoning and other accidents.
I. cause analysis of accidents in open flame operation
hot work itself is an open flame operation process. Whether it is welding or cutting, it is often exposed to combustible, flammable and explosive substances. At the same time, most of it deals with pressure vessels and pressure pipelines, which is very dangerous. The causes of the accident mainly include the following aspects:
1. There are flammable, explosive, toxic and harmful substances in the hot work equipment, which are not treated by the procedures of comprehensive purging, replacement, cooking, water washing, pumping and adding blind plates, or the hot work conditions are not met after treatment, and the hot work is carried out blindly without analysis or inaccurate analysis, resulting in fire and explosion accidents.
2. Acetylene and oxygen used in gas welding and gas cutting are flammable and explosive gases. Tapes, pressure relief valves and other appliances are not in good condition, which are prone to combustion and explosion.
3. During hot work, whether it is gas cutting, gas welding or electric welding, the metal should be melted at high temperature. Molten metal is easy to splash everywhere, causing fire and explosion accidents in the surrounding floor drains, open ditches, dirty oil wells, cable trenches, as well as sampling points, sewage discharge points and leakage points.
4. the oxygen cylinders and acetylene cylinders used in gas welding and gas cutting are pressure vessels, and the equipment itself has great danger. If the violation of safety aggravates the regulations of the industry reshuffle, the improper use, such as the inverted use of acetylene cylinders, the oxygen cylinders and acetylene cylinders do not have anti vibration rubber rings, the acetylene cylinders are used immediately after lying horizontally and rolling, and the safe distance between oxygen cylinders and acetylene cylinders and the hot work point is not enough 10m, Or the safety distance between oxygen cylinder and acetylene cylinder is not enough 3M; Oxygen cylinders and acetylene cylinders are prone to fire and explosion accidents due to heating or gas leakage.
5. When using electric welding, the electric welding machine is not intact or the ground wire and the wire insulation are not good, resulting in ignition with the equipment and pipelines in use. Some welders even lead on other nearby equipment and pipelines, so after impact, they can directly read out the numerical arc of work consumed in the impact sample, causing breakdown of equipment and pipelines, or damage to equipment and pipelines, leaving hidden dangers. Some even connect the grounding wire to the pipeline, equipment and connected steel structure.
6. when using electricity, electric leakage occurs due to poor insulation of wires or tools, or the welder does not wear insulating shoes. Therefore, it is flexible to operate in the container or in a humid environment, resulting in electric shock to personnel, or arc burning skin caused by fuse fusing when switching on.
7. the supervisor is out of position or there is no supervisor; The standard measures are not implemented in place; Push away engineering plastics to replace metal materials. Accidents are likely to occur when environmental conditions change, such as sampling, sewage discharge and leakage, are not stopped in time.
II. Safety countermeasures to be taken before open flame operation
1. Welding and cutting operators and wiring electricians should undergo strict professional training, master certain safety knowledge, safety technology and operating procedures, pass the examination of the technical supervision department and the safety department, and take the post after obtaining the certificate.
2. Strictly implement the hot work management system and approval procedures.
3. For overhaul or high-risk hot work projects, a complete safety construction scheme should be formulated and submitted to relevant departments and leaders for approval. After approval, relevant personnel should be organized to learn and master the key points. Carry out "five handover" to the operators involved, that is, submit construction tasks, safety measures, safety maintenance methods, safety precautions, and relevant safety regulations to be observed.
4. implement the project leader and guardian, implement various preventive measures, and check whether they are in place one by one.