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What are the factors that determine the maximum methanol yield in the methanol synthesis process of combined alcohols? What does a simple calculation look like? What determines the output of methanol in the combined alcohol is the amount of CO participating in the chemical reaction of CO+H2—CH3OH. From the reaction formula, it can be seen that the amount of CO that needs to be converted to produce one ton of methanol is: 1000÷32×22.4=700Nm3/t That is to say, after the synthesis tower is determined, its catalyst loading is also fixed, so the amount of gas passing through the catalyst per unit volume per unit time, that is, the space velocity, is the first factor. For co-hydrol, this space velocity cannot be too high, generally 8000-10000h-1. For example, a Ø800 tower contains 4m3 of catalyst. Then the maximum ventilation volume of the tower is 4×10000=40000 Nm3/h. Since various adjustment methods determine the maximum CO content and catalyst activity in the gas entering the tower, they determine the CO content in the gas exiting the tower. Generally, the CO exiting the tower can reach less than 0.5% at this air velocity, and the CO in the gas entering the tower is determined by the internal structure and process flow, such as ； Judging from the practice in recent years, take uniform temperature internal parts as an example. Process 1: When the main and auxiliary lines are fully open, the CO entering the tower can reach 4%, then the maximum output of the tower at this time should be: Assume the reaction CO amount is X Nm3/h 40000×4%-(40000-3X)×0.5%=X Solve: 1421 Nm3/h. Converted into CH3OH is: 1421÷700=2.03t/h If processes 2 and 3 increase the catalyst volume to 4.5 m3: The CO in the gas entering the tower can reach 6%, and its output can reach: 4.5×10000=45000 Nm3/h 45000×6%-(45000-3X)×0.5%=X Solution: X=2512.6 Nm3/h converted into CH3OH is: 3.59t/h can increase the output by 76.8%. Therefore, when the ventilation rate is certain, the methanol output is determined by the CO content of the tower and the CO conversion rate. That is to say, in order to increase the output, we must try to increase the CO content entering the tower, improve the catalyst activity, increase the CO conversion rate, and reduce the CO content exiting the tower.