The ammonia content in methanol from low-temperature methanol washing is high

Adjust the water flow in the ammonia washing tower, open the ammonia discharge valve, and perform a circulation of methanol for displacement

How do you measure the ammonia in your methanol?

The ammonia scrubber cannot absorb all of the ammonia, which leads to its accumulation in methanol. In methanol, it accumulates at the top of the four towers (methanol regeneration towers), potentially causing blockages in the acidic gas pipelines and concentration pipelines.

1. It may be related to the type of coal; water gas itself contains a high level of ammonia. 2. The efficiency of ammonia recovery through washing is low, and this might be due to the way the washing water is sprayed, as well as its temperature and volume. It’s essentially a problem related to the absorption process; low-temperature systems do not have the ability to remove ammonia, and sending it to sulfur recovery units could cause crystallization and blockages in the acidic gas pipelines

Have you analyzed the ammonia content in methanol?

Ammonia is produced through gasification; the nitrogen in coal or oil is converted into ammonia as a result of gasification reactions. Ammonia is removed in the methanol scrubbing system by two means: one is the ammonia scrubber tower, and the other is sending it to downstream units along with the acidic gases. However, if the ammonia content in the system is too high and these two measures fail to balance it, ammonia will gradually accumulate in methanol. The system needs to monitor the ammonia level at the cold end; if this level is too high, ammonia must be removed from the cold end. We use LUCCHI’s low-temperature methanol washing process; some of its designs do not involve any ammonia emission, while in other cases ammonia is emitted intermittently, just as an excuse to use trucks for transport. There are also piping systems that evaporate the substance to form methanol vapor, which is then sent to downstream combustion. So, if you encounter such a problem, the first thing to do is to analyze the ammonia content in your gasified syngas to see if it has increased. Increase the amount of water used in the ammonia scrubber, and raise the temperature of the hydrogen sulfide-containing gas so that it can carry away the ammonia; of course, this will damage the methanol. If that doesn’t work, then the part of the cold end with the highest ammonia content is transported away using tank trucks for further treatment.

Find out the reason – could it be that the heat exchanger is leaking? Liquids will accumulate there and need to be drained

It comes from the process gases. The high ammonia content in the process gas is mainly due to an excessive ammonia level in the syngas produced by gasification, or to inadequate ammonia removal during washing after conversion, which results in an elevated ammonia content in the process gas fed to the low-temperature methanol wash unit. Accumulation of ammonia content in absorbed methanol. Generally, in the design for sulfur removal and recovery of acidic gases, an ammonia removal line (a heat exchanger bypass) is installed, and the introduction of such a line leads to improved performance. The focus should still be on eliminating the source.

Identify the causes for process gas composition and heat exchanger issues