Atmospheric and vacuum distillation unit in refinery

Atmospheric and vacuum distillation unit in refinery is the general name of atmospheric distillation and vacuum distillation.

Because these two devices are usually together, they are called atmospheric and vacuum distillation devices. Atmospheric and vacuum distillation unit is very important in refinery. The device mainly includes a flue gas waste heat recovery device, which can reduce the excess air coefficient. However, during the operation of the unit, a lot of energy is consumed, and the energy consumption of atmospheric and vacuum distillation unit accounts for more than 25% of the total energy consumption of the refinery.

The fundamental reason why crude oil can be separated by fractionation is that the boiling points of each component in crude oil are different. The necessary condition for liquid boiling is that the vapor pressure must be equal to the external pressure, and lowering the external pressure is equivalent to lowering the boiling point of the liquid. The lower the pressure, the lower the boiling point drop. If the pressure of distillation process is lower than atmospheric pressure, this process is called vacuum distillation.

Problems needing attention in using atmospheric and vacuum distillation unit

1. When the oxygen cylinder deflates or opens the pressure reducer, the action must be slow. If the valve is opened too fast, the temperature of the gas in the working part of the pressure reducer will be greatly increased due to adiabatic compression, which may cause the parts made of organic materials such as rubber packing and rubber film fiber lining to burn out, and the pressure reducer can be completely burned out.

2. Precautions before installing the pressure reducer and when opening the cylinder valve. Before installing the pressure reducer, gently open the oxygen cylinder valve and blow off the dust to prevent dust and moisture from being brought into the pressure reducer. When opening the gas cylinder valve, the gas outlet of the gas cylinder valve should not be aimed at the operator or others, so as to avoid high-pressure gas suddenly rushing out and hurting people.