Production of dimethyl ether, material and mass balances.

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50,000 kilgram/year of dimethyl ether is to be produced,minimizing cost and maximising profit. Dimethyl ether is produced by the catalytic dehydration of methanol over a zeolite catalyst. The reactor feed rate is 400kmol/hour. Fresh methanol is combined with recycled reactant and is vaporised prior being sent to a fixed bed reactor. There is 80% fractional conversiion of methanol at a maximum outlet temperature of 400 degrees centigrade. The reactor effluent is then cooled prior to being sent to the first of two distilation columns. Dimethyl ether is taken overhead from the first distillation column. The second column seperates water from the unreacted methanol. The methanol is recycled back to the front end of the process, while the water is sent to waste treatment to remove trace amounts of organic compounds.The reactor is insulated with the result that heat produced by the exothermic reaction rises. At 80% conconversion with fresh catalyst the reactor temperature goes from 244 to 364 degreees centigrade. Assume that a year equals 8000 hours.