Problems with ammonium salt crystallization in methanol production.

I believe it is mainly ammonium carbonate, as the raw gas undergoing conversion and purification inevitably contains ammonia. After being absorbed in the absorption tower, ammonia is desorbed by heating in the regeneration tower; when it comes into contact with carbon dioxide in that tower, water reacts to form gaseous ammonium carbonate. This gaseous ammonium carbonate, along with the acidic gases, can condense after cooling in subsequent processes, depositing inside pipes or equipment and causing blockages there, as well as leading to excessive pressure in the regeneration tower, which hinders the regeneration process! Based on experience, in actual production this possibility is generally low, but it cannot be ruled out! Therefore, when overpressure is detected in the regeneration tower, solutions can be sought from other aspects first. If none of these methods work, it is possible that ammonium carbonate crystals are forming; in such cases, the valve on the ammonium salt crystal line (also known as the ammonium carbonate crystal line, which is standard in facilities built by manufacturers) connected to the acidic gas line can be opened to quickly relieve pressure and ensure the normal operation of the regeneration tower! At the same time, since the acidic gas is not cooled by a heat exchanger and remains at a high temperature, it heats the ammonium carbonate crystals that are blocked in the pipes or equipment, causing them to melt slowly and ultimately restoring normal operation to the system! To prevent ammonium carbonate crystals from clogging the pipes, a low-point drain can be installed on the acidic gas pipelines, with regular drainage to avoid accumulation over time that could lead to blockages in the pipes or equipment!