The total refrigerating capacity of the expander is related to the expansion capacity and the unit refrigerating capacity. The unit theoretical refrigerating capacity depends on the pressure, temperature before expansion and the pressure after expansion. Therefore, the relationship between the refrigerating capacity of the expander and various factors is:
1) The greater the expansion, the greater the total cooling capacity. For low-pressure air separation equipment, the expansion air is directly sent to the upper tower for distillation, and excessive expansion air volume will affect the distillation effect.
2) When the inlet and outlet pressures are constant, the higher the front temperature is, the greater the unit cooling capacity is. However, as the temperature in front of the unit increases, the temperature after expansion will also increase, and the gas directly entering the upper tower will destroy the distillation condition. During normal production, the range of temperature increase is limited.
3) When the front temperature and rear pressure are fixed, the higher the front pressure is, the greater the unit cooling capacity is. For low-pressure air separation equipment, the inlet pressure of expander in the original process depends on the lower tower pressure, that is, close to the outlet pressure of air compressor. After the booster turbine process is adopted, the external work of the expander is used to drive the supercharger to compress the expansion air from the air compressor, which can increase the inlet pressure of the expander and increase the unit cooling capacity. When the total cooling capacity required is certain, the expansion air volume can be reduced, which is beneficial to the distillation of the upper tower.
4) The lower the pressure behind the expander, the greater the pressure drop inside the expander and the greater the unit cooling capacity. However, as the expanded gas enters the distillation tower, there is little room for pressure change.
5) The higher the adiabatic efficiency of the expander, the greater the cooling capacity.
DEAR Air Separation is a manufacturer specializing in the development, manufacture and installation of various complete sets of air separation equipment, providing customers with high-quality air separation projects.
