Catalytic cracking feedstock tank —— oil-gas equilibrium line issues
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This post was last edited by linweihua6 on 2011-11-1 19:41. Is the gas balance line for the crude oil tank turned off after operations start up normally?---? After our unit returned to normal, the oil-gas balance line being open caused the level of the feed oil to become extremely unstable, so it was turned off. But there is one problem: the absence of an oil-gas balance line leads to increased power consumption of the crude oil pump. I wonder what your thoughts are, guys?
Our unit eliminates the crude oil buffer tank as well as the crude oil pump. It turns out that the gas return line of the crude oil buffer tank leads back to the distillation tower; it is kept open during production and does not affect the liquid level in the buffer tank. The fluctuations in liquid level may be caused by water present in the crude oil.
So what if there are no crude oil tanks or pumps inside the unit? What should be done then? Sent back to the refining tank? In that case, a lot of crude oil will be wasted
Operating heavy oil catalytic cracking generally has no significant effects!
Reply to 1# 0604130131: The gas-phase equilibrium line of the raw material buffer tank cannot be closed, as water in the raw material can cause overpressure in the tank, which is quite dangerous. As for pressure fluctuations in the raw material buffer tank, it is necessary to analyze the properties of the raw material and check whether there are any issues with the piping used for returning the gas phase to the tower (such as liquid accumulation or incorrect installation location). A thorough inspection is required; using the gas-phase return line should help maintain stable pressure in the raw material buffer tank
I personally think the same way—there should be no problem with a bottom pressure of around 150±3 KPA in our distillation column. However, our reprocessing tank is operated at full capacity; it’s likely that the presence of liquid phase in the pipelines is causing the issue. Once one of the check valves in our plant got stuck, we forgot to open the balance line for the crude oil tank, and its pressure rose to 0.8 MPA. It was only during feeding that we realized the nozzle pressure wouldn’t drop. I thought it was really scary at that moment—thankfully, the tank withstood the pressure---
“What does it mean by ‘Failing to open the oil-gas balance line results in increased power consumption of the crude oil pump’?
Reply: Go upstairs----- Heheh, there was a problem with my thinking—I kept thinking that it was the distillation tower that pushed pressure into the crude oil tank. In fact, it should be understood using the principle of vacuum extraction; it’s not the gases from the high-level distillation tower that enter the crude oil tank
Reply to 2# Wen Zhongyu: Friend, which domestic oil refining company do you work for? Can we communicate?
Reply to 3# 0604130131: My unit is a combined unit; it was originally designed to include buffer tanks and crude oil pumps, but those were removed later. The flow is directed back to the reprocessing tank. During production, gas from the reprocessing tank is sent back to the distillation tower. Once the reaction feed is stopped, the crude oil goes directly back to the reprocessing tank, and from there it returns to the distillation tower, with the slurry being discharged to the tank area. If the re-refining pump and slurry pump cannot be started, the incoming crude oil can be stopped directly.