Liquid accumulation stage essentials: ensure that the two expansion machine pressure before the machine is stable, maintain the highest permissible speed, so that it runs at full load. When the condensing evaporator liquid oxygen liquid surface, should promptly close the small oxygen flow to the normal flow of about 1/3, control the upper tower pressure, and gradually close the small liquid nitrogen throttle valve to full shutdown. Timely adjust the amount of air into the tower, to ensure that the air temperature before entering the lower tower as low as possible, increase the amount of moisture into the tower air. When the liquid level rises to 2/3 of the normal liquid level, slowly open the liquid nitrogen back to the lower tower valve, slightly open the liquid nitrogen throttle valve.
The key to adjusting the pure stage: ensure that the condensing evaporator liquid oxygen level in the normal range, and the state of stability, timely adjustment of the expander. In order to ensure the efficient operation of one expander, the other expander gradually reduce the amount until it stops. Liquid-air throttle valve, liquid nitrogen throttle valve and liquid nitrogen back down the tower valve switch to slow, cut to have foresight. When using the liquid-air throttle valve to control the lower tower liquid-air level, use the liquid-nitrogen throttle valve to control the lower tower liquid-air and liquid-nitrogen purity. According to the oxygen purity gradually open up the oxygen delivery valve to normal value. Adjust the nitrogen outlet valve and dirty nitrogen outlet valve to gradually increase the nitrogen purity to the normal index under the premise of ensuring the stability of the upper tower pressure. When the oxygen and nitrogen product purity reaches the target, adjust the expander air into the upper tower gas volume to increase the product output. Seize the important link of liquid oxygen level stability during normal operation and adjust the amount of cold production in time.
Dear Air has many years of experience in manufacturing small air separation units and large air separation units, focusing on all aspects to ensure the overall stable operation of liquid air separation plants.
