When preheating the coke drum, where is the best place to dump the early low-temperature water-containing light components?

Decontamination oil tanks are difficult to recycle directly due to their low temperature and water content. They can be used as quenching oil after dehydration.

The flow rate is relatively small during preheating. Although the temperature is low and contains water, it is more reasonable to pump it into the fractionation tower and will not have a big impact on the operation of the fractionation tower.

I disagree with LLH0111's point of view. Although the flow rate is relatively small during preheating, it is low temperature and contains water, which will also cause large fluctuations in the operation of the fractionation tower.

Entering the venting tower is a good choice. You can use the venting tower for dehydration, and then send it to the waste oil tank for refining.

If a high degree of stability is required, dewater the heavy dirt tank and then recycle it. If fractionation is carried out at the beginning, no matter how good the control is, it may cause fluctuations in the fractionation bottom. I have taken various methods, but none of them have prevented fluctuations. If you don’t want to remove the heavy sewage tank, the best way is to drain the oil tank to vent the tower. After the liquid level in the oil tank rises and the temperature is higher than 200, you can then change to defractionating and starting the oil pump! The person upstairs said that the outlet of the oil pump goes to the air defense tower, but there is rarely a process for the outlet of the oil pump to go to the air defense tower, unless it is the kind of process where the oil dump pump can also be used to vent the circulation pump at the bottom of the tower!

Using a vent tower for dehydration, is the dehydration effect of the vent tower good? Can oil and water be completely separated?

We have set up a self-pressurizing process from oil rejection to the venting tower, which mainly utilizes the pressure difference between the coke tower pressure and the venting tower. In addition, the opening of the venting tower is at a low position, so before 200 degrees Celsius, it flows to the venting tower through gravity flow, and then flows to the waste oil tank for dehydration as quenching oil.； When the temperature at the bottom of the coke tower exceeds 200 degrees Celsius, and the liquid level and pressure of the oil dump tank rise, the fractionation and oil dump pumps are replaced. This not only recovers heat but also saves energy. The key is that the oil dump pump directly uses a centrifugal pump without evacuation.

Go to the venting tower first. When the temperature at the bottom of the tower reaches above 150 degrees, it can be changed to fractional distillation and refining or refining to the raw material tank.

You can add a return line to the oil dump tank through the oil dump pump, and use the internal circulation of the pump to heat up. The generated oil and gas will be sent to the split system through the balance line of the oil dump tank and the oil and gas line at the top of the coke tower. This can well solve the problem of oil dumping and water. However, be careful not to store too much cold oil in the oil dump tank, which will easily cause the cold oil and water in the oil dump tank to suddenly boil, causing system pressure fluctuations.

1. Decontaminate the oil tank and dehydrate it for reuse. 2. It can also be used in the crude oil tank area. 3. It can be used as quenching oil.