Application example 1
Gas expansion in a steel work.
A 4-cylinder gas expander with two-stage expansion was installed in a German steel work. The primary pre-heating upstream from the first stage is performed using operational hot water over a gas-water heat exchanger.
Before entering the second expansion stage, the natural gas must be pre-heated again using a gas-water heat exchanger. After expanding the gas is discharged from the expansion motor at temperature of max. 10 °C. Since the heating agent hot water is only available with a capped temperature, the natural gas cannot provided at the desired temperature of 20 °C for use after the expansion. That is why it is again heated up over a downstream hot water-gas heat exchanger after being discharged from the expander.