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Precautions and factors of capacity ofoperating a booster expander in liquid air separation plant

Precautions and factors of capacity ofoperating a booster expander in liquid air separation plant
Jun 19, 2025
Author: DEAR AST

The following precautions should be taken in the operation of a pressurised expander:

1 do not allow the interlock to be removed to start the expander in liquid air separation plantunder any circumstances.

2 control the inlet temperature of the expander to be no lower than -118°C.

3 it is not permitted to start the expander with the booster bypass valve FCV401 closed, and the expander should be pre-cooled before it is used for the first time or put into use in a hot state.

The size of the expander's refrigeration capacity is related to :

The total cooling capacity of the expander in liquid air separation plantis related to the expansion volume, the unit cooling capacity, while the unit theoretical cooling capacity depends on the pressure before expansion, the temperature and the pressure after expansion.

Therefore, the refrigeration capacity of the expander is related to the various isotopes as follows

1 the greater the expansion volume the greater the total refrigeration capacity.

2 the inlet and outlet pressure is certain, the higher the temperature before the machine, the greater the unit cooling capacity;

3 when the temperature before the machine and the pressure after the machine is certain, the higher the pressure before the machine, the greater the unit cooling capacity.

4 the lower the pressure after the expander, the greater the pressure drop in the expander, the greater the unit cooling capacity.

5 the higher the adiabatic efficiency of the expander, the greater the refrigeration capacity.

Dear Air Separation has strict specifications in the basic operation of liquid air separation plant and small air separation unit and large air separation plant to achieve safe operation and maintenance, stable and efficient operation.

秦皇岛安丰钢铁有限公司KDON(Ar)-1600020000-500型空分设备

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