What is Chinese synthetic ammonia technology from?

Most domestic large-scale synthetic ammonia plants using coal as raw material adopt imported technology, which is in sync with international advanced technology. For example, pressurized coal water slurry gasification, Lurgi pressurized gasification, dry coal powder pressurized gasification are used for gasification. Sulfur-resistant conversion, low-temperature methanol elution for sulfur decarburization, liquid nitrogen washing and refining processes are mostly used for purification. Low-pressure ammonia synthesis is used for synthesis. centrifugal compressor is used for compression.

The gasification process of domestic small and medium-sized synthetic ammonia plants mostly adopts the atmospheric pressure fixed bed intermittent gasification process (UGI) or the Ender gasification and ash fusion gasification process with anthracite lump coal or coke as raw materials. The purification process mostly adopts wet oxidation desulfurization (tannin extract, improved ADA, 888, etc.), medium-low or full-low variable conversion process, chemical method (hot potash) or physical chemical method (MDEA) or physical method (propylene carbonate , NHD, PSA) decarburization, copper washing or methanation (or alcohol alkylation) refining. The synthesis adopts a pressure of 25~31.4MPa. The compression adopts a reciprocating compressor. At present, the energy consumption per ton of ammonia in China's small and medium-sized synthetic ammonia plants using coal as raw material is 51.5GJ.

Most domestic small and medium-sized urea plants (less than 600 t/d) adopt the full circulation method of aqueous solution, most of which with a production scale above 1000 t/d use the improved CO stripping process.