The lessons we learn from the accident

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This post was last edited by Ruilin369 on 2018-9-9 at 11:06. Recently, this news has reached all petrochemical companies across the country, as virtually all refineries have hydrogenation facilities. The entire accident, from its onset to completion, lasted 6 minutes; one employee aged 49 and another aged 52 died, making it a tragic incident. If this accident had not occurred, they would have continued to go to work and come home as usual until retirement... But it was precisely this accident that deprived them of the chance to enjoy their later years, becoming a source of sorrow for their families and society as well. Let’s first take a look at several issues that occurred during this accident: 1. Why did the compressor oil pressure drop? 2. Why is the oil pressure also low after the standby pump starts? 3. What actions were taken on site during the 6 minutes from when the device interlock occurred until the accident took place? Next, let’s analyze the issues that arose throughout this entire incident: 1. What causes the drop in oil pressure? Is it the large fluctuations in water temperature due to oil cooling, or is it something like a clogged filter? Why did the auxiliary pump start even though the oil pressure was not adjusted, and why did a chain shutdown occur as the oil pressure continued to drop? 2. What is the lubricating oil pressure after the auxiliary pump starts? When adjusting the oil pressure before starting up, do we need to increase the oil pressure of the auxiliary oil pump by 0.35–0.4 Mpa? 3. With 1 hour for oil pressure adjustment, why not switch the compressor? 4. Why wasn’t the pump outlet control valve closed quickly after the chain shutdown? 5. Why do the two check valves in the reaction system not function? 7. Why was the emergency pressure relief procedure not activated? Even if all the above steps are followed, it will not prevent accidents from occurring; yet, one layer after another of these protective barriers fails. If you examine the entire incident carefully, you will find that things are not actually like that. After this incident, I went to Qita Petrochemical the next day. Their facilities are larger; the plants were designed by Luoyang Institute and construction began in 2012. Emergency shut-off valves are installed at the outlet of the feed pump as well as on the return line, the high-pressure water injection line, and the lean solvent line used for hydrogen cycle desulfurization in their hydrogenation units. In other words, some design institutes failed to consider these aspects thoroughly, or the design standards used in the past were relatively low. This is what we refer to as intrinsically safe design, and it clearly demonstrates the importance of hardware in such devices. Is that’s how it ends? Not yet. Because we have only learned* it, but not yet applied it. Has been verified whether the check valve has internal leakage? Are the valves of the standby pumps and equipment leaking internally? Is it necessary to specify a dedicated program before performing the commissioning interlock for equipment equipped with an auxiliary oil pump? Are emergency shut-off valves necessary at the locations where high pressure can easily leak into low pressure? What is the opening degree of the primary valves (thermometers, level gauges) in the high-temperature and high-pressure areas? Should the emergency response procedure after device interlocking be revised? .......Heinrich’s Law tells us that when a company has 300 potential hazards or violations, 29 minor injuries or failures will inevitably occur; among these 29 accidents or failures, there will be one case of serious injury, death, or a major accident. In other words, if we are unaware of or indifferent to potential accidents, it will lead to irreparable losses. Murphy’s Law tells us: “If something bad can happen, no matter how small the probability, it will happen and cause the greatest possible damage.” ” Murphy’s Law tells us that a tendency to make mistakes is an inherent weakness of humans; no matter how advanced technology may be, accidents will still occur. Moreover, the more sophisticated our methods for solving problems are, the more serious the troubles we face. Therefore, we should try to be as thorough and comprehensive as possible in advance; if misfortune or losses do occur, let’s face them with a smile. The key is to learn from the mistakes made, rather than trying to hide them. Facing an accident head-on is in itself a form of growth!