Summary of safety accident cases caused by instrument problems
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Accident name: The air separation compressor trip accident in the methanol plant. The accident: At 10 a.m. on August 17, 2007, the air separation section proposed to restore the turbine exhaust pressure (PI9015) too high interlock. When the interlock was turned on, the air compressor exhaust pressure was too high and tripped because it was not reset. ""Shutdown reset" is generally reset before the air compressor is shut down and started again. After the exhaust pressure transmitter failed and the interlock was released last time, the exhaust pressure reached the interlock value and was not reset, which led to this trip accident. Cause of accident: 1. The operator was negligent when turning on the interlock and did not confirm the relevant interlock conditions in detail. 2． The operator did not fill in the "interlocking vote" as required, and did not notify the supervisor in advance and obtain approval.
Accident name: On February 19, 2015, an explosion and combustion accident occurred in the 2# granulation tower of the nitro compound fertilizer workshop of Hubei Yichang Fusheng Chemical Co., Ltd., resulting in 5 deaths and 2 injuries. Cause of accident: The temperature of a mixing tank exceeded the control index of 175°C for one hour, resulting in * * It decomposes when heated, and the temperature instantly reaches over 600 degrees ( * aoan acid decomposes violently above 400°C and explodes: 4NH4NO3→3N2+2NO2+8H2O), and the device was not equipped with automatic over-temperature control measures, causing the slurry in the first mixing tank to spray out and flow to the 100m and 96m layers, causing high-temperature decomposition and deflagration.
Accident name: On April 9, 2016, a fire accident occurred at Tianlihai Flavors and Fragrances Co., Ltd. in Xinglong County, Chengde City, Hebei Province, resulting in 4 deaths and 3 injuries. The accident: After the shift handover meeting at 19:00 on April 9, the operators of the hydrolysis kettle in the second chemical workshop began to discharge materials and catch chlorine, and began to heat up and distill methanol around 20:00. At 21:18:26, according to the combustible gas detection and alarm device in the monitoring room, the combustible gas monitoring alarm on the second floor of the workshop alarmed. Materials in the 4# hydrolysis kettle system leaked and deflagrated, causing 2 operators to die on the spot, and 2 others to die from serious injuries. ； Three people performing maintenance work nearby suffered burn injuries. Cause of accident: The instantaneous pressure increase in the 4# hydrolysis kettle caused the lower part of the flange connection between the hydrolysis kettle head and the kettle body to tear. Inflammable and explosive gases containing methanol and other materials rushed out rapidly and rubbed against the air, deflagrating and causing a fire.
Accident name: On August 15, 2016, a deflagration accident occurred during the renovation of the foam generator in the methanol storage tank of Inner Mongolia Duolun Coal Chemical Company, resulting in 2 deaths and 1 injury. Cause of accident: Before the accident, the nitrogen pressure in the methanol tank area was too low for a long time, causing the nitrogen protection of the methanol storage tank to fail. Air entered the storage tank through the breathing valve. At the same time, when the operator removed the blind plate of the foam pipeline during the operation, the air entered the storage tank through the foam pipeline, forming an explosive mixed gas. It exploded when encountering sparks generated by fire, welding line ignition, or non-explosion-proof tools. The accident exposed the company's inadequate control over special operations such as fires.
Accident name: On October 14, 2016, a leakage and explosion accident occurred in the syngas compressor of Jinkai Chemical Investment Holding Group Co., Ltd. in Kaifeng City, Henan Province, but no casualties were caused. Cause of accident: One of the valve air inlet gland bolts at the inlet of the sixth section of the No. 5 compressor in the compression section of the second system synthesis workshop of the group company's branch company broke. The mixture of hydrogen and nitrogen (working pressure 10.5MPa) in the compressor leaked and formed an explosive mixture with air. When encountering an ignition source or static electricity generated by high-pressure gas friction, it deflagrated. Keep the lessons learned from the accident in mind, conduct instrument maintenance, and ensure long-term normal operation of automation equipment. The maintenance process should be done: Often, maintenance work is carried out on a daily basis ； Meticulous, you must be careful when performing maintenance work ； Scattered, there are many reasons for failure. No maintenance will be performed under the following conditions:: 1. Construction (pipeline construction, equipment installation) is taking place near the instrument, which affects life safety and will not be inspected or repaired. ； 2. There is a large leakage of toxic and corrosive gases or liquids such as hydrogen fluoride, 98% sulfuric acid, fuming acid, fluorosilicic acid, and ammonium bifluoride at the installation site. ； 3. If there are no protective equipment or protective facilities on site, maintenance will not be allowed.
Instrument engineer's illegal operation caused LNG injection fire accident https://bbs.hcbbs.com/thread-3272316-1-1.html (Source: Haichuan Chemical Forum)
Excuse me: Are these instrumentation issues? resulting accidents. misunderstanding