Let’s discuss to what temperature the feed gas cooler should be pre-cooled during the start-up of the methanol wash unit

We use the Luchi process, where the process gas exchanges heat with the gas exiting the low-methane column before entering the tower. There is also an ammonia cooler, and the temperature of the process gas exiting this cooler is only eight degrees. When introducing the process gas, the flow rate is 10,000 standard cubic feet per hour, and the temperature of the gas entering the tower at the beginning of this process must not exceed 8 degrees.

Methanol scrubbing for nitrogen removal is activated half an hour in advance before driving the process, solely to shorten the gas guiding time, produce qualified process gas as quickly as possible, and reduce waste. As for what temperature it should be cooled to, there’s probably no standard? As long as the process gas obtained through conversion is of satisfactory quality, the pilot gas should also be fine. It’s just that more water will flow into the absorption tower. If the transformation process is already qualified, will no gas be introduced in the absence of N2? It should still be gas-guided; in this case, qualified process gas can still be produced, although there is greater heat loss, a higher content of acidic gases and CO2, and a higher load on the reboiler of the thermal regeneration tower. This post was last edited by cuikk on 2009-3-14 16:45]

I completely agree with the opinion above; introducing nitrogen for stripping in advance is mainly aimed at pre-cooling the raw gas heat exchanger, so as to prevent high temperatures from the shift gas from causing an elevated water content in the system. There is no specific target for the degree of pre-cooling required!

The ammonia-cooled refrigeration system reaches -20 degrees, while the propylene one reaches -30 degrees