The temperature drop of air from 0.6MPa to 0.1MPa is only about 1 ℃, while the temperature drop can reach 80~90 ℃ in theory through expansion of expander, and the temperature drop effect is much better than throttling.
The reason is that the throttling process does not output external work, and the temperature reduction is caused by the increase of molecular potential energy. When the gas expands in the expander, the gas should push the impeller to rotate or push the piston to work externally. Moreover, the expansion process is fast and there is no external energy input. Ideally, it can be regarded as an adiabatic process. According to the law of conservation of energy, the output work can only be balanced by reducing the energy (enthalpy) of the gas, which makes the kinetic energy of the gas molecular motion decrease sharply, which is reflected in the large drop in temperature. Therefore, during the expansion of the expander, the temperature drop of the gas is not only caused by the decrease of pressure, resulting in the increase of molecular potential energy, but also the decrease of kinetic energy of molecular motion. It is mainly caused by external work, so the effect of temperature drop is much greater than that of throttling.
DEAR Air Separation has rich project engineering experience, and continuously uses innovative technologies to optimize equipment energy conservation and safety. It is the main manufacturer and gas supplier of air separation equipment in China.
