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This post was last edited by Aggregated Cat_IEB8P on 2020-6-30 at 10:23. 1. Preparation of feed gas: This process is carried out to prepare feed gas, which is primarily composed of hydrogen and nitrogen. At high temperatures, water vapor and the raw materials for hydrogen production are mixed together to produce a gas containing carbon monoxide and hydrogen. For different raw materials, different methods are generally used to produce syngas. For example, non-catalytic partial oxidation must be used for residue, while for certain solid feedstocks, a method of gasifying the solid fuel is required. Nitrogen is the most abundant component in air, so it can be produced by the physical method of liquefying air. Not only that, but chemical methods can also be employed; that is, by allowing carbon to undergo a vigorous redox reaction with air, and then separating out the carbon dioxide produced, pure nitrogen can be obtained. 2. The liquefaction and separation of air: Air is frozen and liquefied. Since the boiling points of the various components in air differ significantly, distillation can be used to separate air into pure gases. 3. Purification of raw gas: In the ammonia synthesis process, purifying the crude raw gas is a crucial step that cannot be ignored. The following will provide a detailed analysis of the various processes involved in this stage: (1) The raw gas obtained from carbon monoxide conversion and gasification contains mostly toxic carbon monoxide; it is necessary to convert this into carbon dioxide, which can be easily removed, while increasing the proportion of hydrogen in the effective gases, in order to improve the productivity of the ammonia synthesis process. In fact, the step that consumes the most energy in a complete industrial process is carbon monoxide conversion. Therefore, if the energy consumption in this manufacturing process can be reduced, resource waste can be significantly minimized. (2) Raw gas desulfurization and decarburization process: The decarburization and desulfurization of raw gas are also very critical steps. Decarburization is primarily aimed at preventing catalyst poisoning in the ammonia synthesis process, and it can generally be achieved through either chemical absorption or physical absorption. It should be noted that since carbon dioxide can be used as a raw material for producing substances such as sodium carbonate and ammonium bicarbonate, it is necessary to recover and reuse carbon dioxide during the decarburization process. This not only helps to save energy but also contributes to the protection of the natural environment. The desulfurization process can generally be carried out using either dry desulfurization or wet desulfurization. The use of solid desulfurizing agents corresponds to dry desulfurization; although it yields good results, it is not conducive to the regeneration of the desulfurizing agents. Using solution desulfurization is a wet desulfurization method; the desulfurizing agent can be regenerated, and it is widely used in the crude desulfurization process. (3) Purification of feed gas: After refining, decarburization, and desulfurization, the feed gas still contains many impurities, including small amounts of carbon dioxide and carbon monoxide, which can provide some protection for the catalysts used in ammonia synthesis. In the industry, the copper-ammonia solution absorption method is generally used to purify raw gas.