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Dimethyl Ether (DME) is a proposed alternative to diesel fuel that is being looked into by car and truck manufacturers worldwide. The current market, based almost completely in China, is primed for growth and a U.S. based DME total plant that is economical and environmentally feasible stands to pave the way for America’s DME market, especially since states such as California have approved DME for use as vehicle fuel (Fuel Smarts). Conventionally, the DME is produced by feeding Methanol into a xed-bed gas-phase reactor over a ɣ-alumina catalyst (Dimian et al). Using this process and normal operating conditions (250-400°C and up to 20 bar) operations can reach 70-80% Methanol conversion. The proposed process utilizes the innovative reactive distillation technology and Amberlyst 35 catalyst to achieve a 99.8% Methanol conversion and produce 35,418 kilograms of DME fuel per hour. The reactive distillation is executed at ~130°C (in the reactive stages) and 700 kPa (condenser pressure), and produces water as a byproduct, which exits as the bottoms stream. In order to create a process that is environmentally sustainable, the small amounts of Methanol and DME in the bottoms stream are removed using biotreatment and the water is then released into a nearby river. The product DME is mixed with mineral oil to meet ISO standards and is then stored in an on-site spherical tank farm. Diesel prices will be undercut by the DME product at $1.716 a gallon in order to incentivise companies to make the switch to DME fuel.
The DME total plant, located in Beaumont, Texas, serves to provide the local long-haul trucking industry with a cleaner burning fuel for a plant life of 20 years. The DME total plant has an Internal Rate of Return (IRR) of 12.6%, a Net Present Value (NPV) in 2020 of approximately $12 million, and will turn its rst pro t in 2033. The report addresses nancial, economic, and process concerns to deliver recommendations for the construction that is safest for the environment, the investor, and the plant operator.
Date Posted: 11 May 2020