ASU manufacturer

The purified air enters the fractionator and exchanges heat with the returned polluted nitrogen, oxygen and nitrogen through the main heat exchanger. After cooling, a small part of it is liquefied, and the gas-liquid mixed air is throttled to the pressure of 0.55 MPa. After distillation, 99.999% pure nitrogen is obtained at the top of the lower column, and then it enters the main cooling column, and is condensed into liquid nitrogen by evaporation of liquid oxygen in the upper column. A part of liquid nitrogen is returned to the lower column as reflux liquid, and the remaining liquid nitrogen is throttled after cooling. Enter the sprayer at the top of the upper column. The bottom residue is liquid air containing 38% oxygen. After passing through the liquid air subcooler, it enters the middle of the upper column to participate in distillation. At the same time, the polluted liquid nitrogen flow is drawn out from the middle of the lower column and then enters the upper column as reflux l

The leakage of unit or pipeline in the cold box needs removal of perlite treatment. Since it is uncertain whether there is a leakage point in the cold box, it will have a certain impact on removal of perlite. No matter whether the leakage is liquid or air, the sand filling holes at the top should be opened first, so that the residual gas in the cold box can be slowly discharged into the atmosphere. The oxygen content of the gas in the cold box and the pressure indication in the cold box should be strictly monitored in removal of perlite process. In the process of sand stripping, it is particularly important to avoid the formation of sand free area in the middle of the cold box, so as to avoid sand storm caused by the sudden drop of pearlite sand.