Production of Dimethyl Ether as an Alternative Automotive Fuel

Global climate change, depletion of fossil fuels and a growing energy demand have created a need for reliable, safe and clean fuel alternatives to fossil fuel. Dimethyl ether is an appealing option due to its high cetane number and its low-polluting combustion. A manufacturing plant was designed and cost-evaluated for the conversion of biosolids into dimethyl ether. Biosolids, such as firewood and agricultural waste, are reformed at high temperatures to generate syngas, a mixture of hydrogen gas, carbon dioxide and carbon monoxide. A reactor was designed to react the syngas over catalyst to produce methanol. The catalyst is bifunctional and also aids in dehydration of methanol to produce dimethyl ether within the same reactor. A separation process design was created to purify dimethyl ether to ASTM fuel standards and to capture unreacted methanol for process recycling. This design is a cost-effective, safe, green alternative to fossil fuels.