As the air passes through the accumulator or the switching heat exchanger, water and carbon dioxide precipitate out and freeze on the packing of the accumulator or on the fins of the switching heat exchanger, and the return flow of dirty nitrogen takes away the deposited water and carbon dioxide when it passes through.
The dirty nitrogen from the upper tower of the distillation column in large air separation plant contains essentially unsaturated water and carbon dioxide, so that the water and carbon dioxide can evaporate and sublimate and then enter the dirty nitrogen gas. Although the temperature of the dirty nitrogen is lower than that of the positive flow air, and the saturated content of water and carbon dioxide that can be contained in the dirty nitrogen is less than that brought in by the positive flow air, the actual volume of the dirty nitrogen is 3 - 4 times larger than that of the positive flow air because the pressure of the dirty nitrogen is much lower than that of the positive flow air, so the actual capacity of water and carbon dioxide that can be contained is larger than that of the positive flow, and all the dormant water and carbon dioxide can be to achieve the purpose of self-cleaning.
Dear Air Separation large air separation plant and small air separation unit have very mature production technology and can produce all the air separation equipment required by the market.