Reasons for insufficient cooling capacity in the low-temperature methanol washing unit
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What are the reasons for insufficient cooling capacity in the low-temperature methanol washing unit?
1. Excessive methanol circulation volume… 2. Too much steam added… 3. Incomplete CO2 separation… 4. Excessive nitrogen carried away by stripping, taking some of the cooling capacity with it… 5. Poor heat exchange efficiency of liquid ammonia (high liquid level resulting in poor evaporation)
There are also leaks on site, and the insulation is inadequate. The stripping nitrogen is too low. The operating pressures of Towers 2 and 3 are low. The flow rate in the concentration pipeline is low.
As a supplementary point, excessive accumulation of system impurities has caused blockages in the water cooler and ammonia cooler pipes
This post was last edited by Botian on 2012-7-21 at 18:24. 1. The methanol circulation rate is significantly too high. 2. The amount of nitrogen used for stripping is excessive. 3. Refrigerants such as propylene or ammonia are not effective. 4. The refrigerant contains a high proportion of nitrogen. 5. The heat exchange efficiency of the heat exchangers is poor. 6. CO2 is not completely removed. These are my personal opinions; a precise assessment requires process parameters!
The most likely possibility is that there is a problem with your ice machine, or there is an issue with the liquid level in the cryocooler
I believe that an excessive level of moisture in methanol within the system leads to an increased specific heat, which in turn causes the system temperature to rise
Large methanol circulation volume; nitrogen gas stripped in insufficient or excessive amounts; insufficient heat exchange between carbon dioxide and the feed heater; low amount of cold energy removed from the syngas through liquid nitrogen washing; large amount of cold energy carried away by carbon dioxide along with the exhaust gases; inadequate insulation; leaks; reduced cold energy supply from the ammonia cooler, etc