Differences between gasification processes for ammonia and methanol synthesis
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As the title says. The process flows for ammonia synthesis via gasification and methanol synthesis via gasification are roughly the same. Since I have not been to the sites in person, I am very interested in understanding the differences between the two (there must be some differences, right?), including aspects such as working principles, process steps, and process conditions. As the saying goes, what is difficult is not done by those who are unskilled; what is easy is done by those who are skilled. Thank you in advance!
Wow, the differences between these two are huge. Apart from the gas production step at the beginning, the rest of the processes are quite different. Methanol: gas production (either in one stage or through two-stage conversion with pure oxygen) – compression (5-8 Mpa) – synthesis – distillation – final product. Synthetic ammonia: gas production (two-stage conversion, with air added in the second stage) – medium-low pressure shift reaction – decarburization – methanation – compression (15-30 Mpa) – synthesis. The differences can be seen from their chemical components; one contains carbon and hydrogen while the other contains nitrogen and hydrogen, which is why their production processes differ significantly. People often compare these two because both can be produced from natural gas or coal using essentially the same gas production processes.
Firstly, gas production is different; the gas produced in ammonia synthesis is semi-water gas. Methanol gas generation produces water gas. Semi-water gas is different from water gas.
Thank you so much to the kind person! The difference between chemical elements and reaction equations is obvious; they are simply two different things. Perhaps it isn’t necessary for those working in process development, but I think it is quite important for teaching purposes So, what do you think? When setting up professional courses, should schools offer one course or two? (I’m a teacher.) It’s a contradiction: if one course can’t be explained clearly, then two courses would be too verbose, right? This post was last edited by qinyun73 on 2009-3-20 13:02.]
Gasification for synthetic ammonia production: (1) After gasification, the gas undergoes conversion processes (complete conversion of CO to hydrogen), desulfurization, decarburization, and gas purification, resulting in a purified gas with a H2/N2 ratio of 3:1, which is then fed into the ammonia synthesis system. (2) Nitrogen in syngas is an active gas; depending on the coal gasification process, nitrogen supplementation may be required or not. Gasification to produce methanol: (1) After gasification, the gas undergoes sulfur-resistant shift reaction (part of the CO is converted into hydrogen), desulfurization, decarburization (part of the CO is converted into hydrogen), and further desulfurization (dechlorination), to yield a qualified feed gas with a hydrogen-to-carbon ratio of around 2.05–2.1, which is then sent to the methanol synthesis system ； (2) Nitrogen in syngas is an inert gas, and it is desirable to have as low a nitrogen content as possible in the syngas produced by coal gasification.
There’s a big difference; in terms of unit operations and the target product, the synthesis of ammonia is much more complex than that of methanol