Where is H2S likely to leak in a hydrocracking unit? ?

During sampling, during water separation and cutting processes, and also if there are acidic gas pipelines, hydrogen sulfide leaks can easily occur at the flanges, valves, and other components on such pipelines.

Leakages can occur at normal dynamic and static sealing points (such as pumps, fans, valves, instruments, flanges, etc.) as well as during sampling.

Provide specific examples; it’s more convincing that way. 1. On November 10, Zhang Jianzheng, a young worker from the third hydrocracking shift, carried out thorough inspections and promptly detected and resolved a liquefied gas leakage incident, ensuring the stable operation of the facility. At 11:30 a.m. that day, Zhang Jian, who was responsible for the outdoor operations related to hydrocracking, was conducting an inspection inside the facility when he noticed a white mist surrounding liquefied gas pump P305. Upon approaching, he found that the seal of that pump had failed, causing a hissing sound. Since the liquefied gas in this pump contains a high concentration of hydrogen sulfide, if not dealt with promptly, hydrogen sulfide reactions may occur, or even flash explosions. Faced with the emergency, Zhang Jianzheng remained very calm and composed, promptly reporting the situation to the squad leader. Under the command of the shift leader, the operators, wearing air respirators, promptly stopped the operating pump, closed the inlet and outlet valves, and started the backup pump at the same time. Immediately thereafter, contact the blacksmith to handle it. 2. On the 17th, it was learned from Guangdong Maoming Petrochemical Company that, following an on-site inspection by the safety and environmental protection authorities, the cause of the fire that occurred on the 16th in the hydrocracking unit of the company’s refinery was preliminarily determined to be a leak and subsequent ignition due to a burst pipe in the furnace area; the fire did not cause any environmental pollution. 　　At around 4:20 p.m. on the 16th, a fractional distillation heater in Unit 1 of the hydrocracking unit at the Maoming Petrochemical Company’s refinery caught fire. The staff on duty immediately activated the emergency safety interlock shutdown system in accordance with the emergency plan, turned on the fire suppression systems surrounding the site of the fire to carry out initial firefighting efforts, and used spray systems to protect the surrounding equipment. The local fire department dispatched a total of thirteen fire trucks to the scene of the fire to fight it, and the fire was brought under control by 5:10 p.m. that day. Due to the leakage of hydrogen sulfide-containing materials at the scene, in order to prevent the spread of these materials after firefighting, the on-site emergency command center decided to control the combustion rather than extinguish it completely, until the hazardous materials were eliminated. 　　According to the latest reports, this incident did not result in any casualties, no environmental pollution was caused, and it had no impact on the safe operation of surrounding communities or other production facilities. 3. On August 7, 1999, a hydrogen sulfide pipeline in the hydrocracking unit of a factory leaked, and an employee collapsed due to exposure to the gas while conducting inspections. Upon discovering this, the team leader immediately put on a gas mask to carry out the rescue. During the rescue effort, he was also overcome by hydrogen sulfide because he was wearing an activated carbon gas mask that was not resistant to hydrogen sulfide. This accident resulted in two deaths. :lol :victory:

Besides what was mentioned above, let me talk a bit about my own experience: after stamping in the rich liquid flash tank, N2 is turned off; there are two hand valves in total, with a drain valve between them. I didn’t think much of it and turned off the one that was further away from the tank; as a result, there was a leak in the drainage system. Fortunately, the alarm device prevented any problems from occurring

On-site level gauges with high and low readings. The reaction system, the circulating hydrogen system, and the top section of the butane removal tower all have high hydrogen sulfide levels. No matter where a leak occurs, it is essential to wear proper personal protective equipment – your health is the foundation of everything.