This post is the continuity from
Production Plant Problem # 2 - Inconsistent Pump Flow and
Production Plant Problem.
...Finally we came out with a very risky idea but can solve the problem faster. We have to maintain a slight vacuum inside the buffer tank just to hold the oil from pouring out of the leaking hole. We must attain the right balance i.e. to avoid oil from coming out of the vessel so that welding can be done; and to avoid spark from entering the vessel to avoid fire. We gathered enough manpower to execute and monitor the job.
The welding job runs smooth. Due to lack of time, we could not conduct air or steam test to really ensure that the welded portion is properly sealed. With that in mind, the fitters must properly weld the leaking section. They welded a few layers to ensure there’ll be no leaking at all.
While the welding job is in progress on the ground floor, another big vessel on the first floor was externally caught on fire. Smoke rushed out from underneath the insulation and we can see fire coming out of it as well. We swiftly grabbed the fire hose and spray water towards the fire.
It was the insulation wool that was actually burning. The big vessel has some hidden leak and when the plant breaks vacuum, oil came out of it. Combination of oil, high temperature and air triggered the fire as the flash point was reached. That was not the first time. It had happened several times during plant start up or stoppage. Luckily, we managed to put off the fire. However, we continued spraying water to cool down the hot insulation wool. We also poured few pails of low concentrated caustic to encapsulate all leaked oil (hydrocarbon molecules) in the insulation wool.
As soon as the situation on the first floor was under control, the welding job on the ground floor was also completed. Everything looked fine and the plant is ready to start. The vacuum system was slowly established and crude oil is pumped into the plant. After I was really satisfied with the overall situation, I left the plant, relieved that we have identified the prime pumping problem that haunted us all these while. It was already dark and I was very exhausted.
That was the problem # 2 that recently occurred in the plant. I shall continue with problem # 1 followed with problem # 3 in few days time. Oh yea, the photos are not actual events of what occurred in the plant.
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