Under the high pressure of 200MPa and high temperature of 500℃, under the action of catalyst, N2+3H2 = = = 2nh3 was compressed and condensed, and the residue was sent back to the reactor for reaction.
Synthetic ammonia refers to ammonia directly synthesized by nitrogen and hydrogen at high temperature and high pressure in the presence of catalyst. Except for a small amount of by-products recovered from coke oven gas, most of the ammonia in the world is synthetic.
Synthetic ammonia is mainly used as fertilizer, refrigerant and chemical raw materials.
Production method The main raw materials for producing synthetic ammonia are natural gas, naphtha, heavy oil and coal (or coke).
① Ammonia production from natural gas. Natural gas is desulfurized first, then converted twice, and then subjected to carbon monoxide conversion and carbon dioxide removal, respectively, to obtain nitrogen-hydrogen mixed gas, which still contains about 0. 1% ~ 0.3% (by volume) of carbon monoxide and carbon dioxide. After methanation, the pure gas with the molar ratio of hydrogen to nitrogen of 3 is produced, which is compressed by a compressor and enters the ammonia synthesis loop to obtain the product ammonia. The production process of synthetic ammonia with naphtha as raw material is similar to this process.
② Ammonia production from heavy oil. Heavy oil includes all kinds of residual oil obtained from deep processing. Synthetic ammonia feed gas can be obtained by partial oxidation. The production process is simpler than natural gas steam conversion, but an air separation device is needed. Oxygen produced by air separation unit is used for heavy oil gasification, nitrogen is used as raw material for synthetic ammonia, and liquid nitrogen is also used as detergent for removing carbon monoxide, methane and argon.
③ Ammonia production from coal (coke). With the development of petrochemical industry and natural gas chemical industry, the method of making ammonia from coal (coke) is rarely used in the world.
Purpose Ammonia is mainly used to make nitrogen fertilizer and compound fertilizer. As an industrial raw material and ammoniated feed, ammonia accounts for about 12% of the world output. Nitric acid, various nitrogen-containing inorganic salts, organic intermediates, sulfonamides, polyurethane, polyamide fibers, nitrile rubber, etc. all directly need ammonia as raw materials. Liquid ammonia is often used as a refrigerant.
Some stored and transported commercial ammonia is transported from the factory to other places in liquid form. In addition, in order to ensure the balance between supply and demand between synthetic ammonia and ammonia processing workshops in the factory and prevent production from being stopped due to short-term accidents, it is necessary to set up a liquid ammonia warehouse. There are three types of liquid ammonia storage: non-freezing, semi-freezing and full freezing. Liquid ammonia can be transported by sea, barge, pipeline, tanker and truck.
Synthetic ammonia is a complete set of synthetic ammonia production projects that our company can contract, with the scale of 4× 104 tons/year, 6× 104 tons/year,/kloc-0 ×104 tons/year and 30× 104 tons/year.
1. Process route:
The common method for producing synthetic ammonia from anthracite are:
Gasification->; Semi-water gas desulfurization->; Compressor 1, part 2->; Transform->; Shift gas desulfurization->; The third stage of compressor->; Desulfurization->; Compressor parts 4 and 5-> copper washing->; Compressor 6->; Synthetic ammonia->; Product NH3
When methanation is used to remove CO. CO2 from feed gas, the process flow chart of synthetic ammonia is as follows:
Gasification->; Semi-water gas desulfurization->; Compressor 1, second stage->; Transform->; Shift gas desulfurization->; The third stage of compressor->; Decarburization->; Fine desulfurization->; Methanation->; Compressor stages 4, 5 and 6->; Synthetic ammonia->; Product NH3
2. Technical indicators:
(1) Raw coal: anthracite: particle size 15-25mm or 25- 100mm.
Fixed 75% steam: pressure 0.4MPa, 1-3MPa.
(2) Products: synthetic ammonia: ammonia content (99.8%) and residue content (0.2%).
3. Consumption quota: (calculated by 4× 104 tons/year)
(1) anthracite (loaded): 1, 300kg.
(2) Electricity: 1 1,000 kwh (carbonization process) and 1 1,300 kwh (decarbonization process)
(3) Circulating water: 100M3
(4) Coverage area: 29,000 square meters
4. Main equipment:
(1) gasifier
(2) Compressor
(3) Copper washing
(4) Synthetic tower