Feasibility Study of an On-Board Natural Gas to Dimethyl Ether Reactor for Dimethyl Ether Preinjection and Enhanced Ignition

Abstract

Dual fuel (CI) engines provide an excellent means of maintaining high thermal efficiency and power while reducing emissions. This is particularly true in situations where the main CI fuel does not exhibit good autoignition characteristics, such as diesel engines operating on natural gas usually in stationary applications such as a pipeline installation. This paper explores the feasibility of chemically synthesizing DME from natural gas “on-board” and using it as an ignition source for a dual fuel engine. Conversion from diesel to dual fuel operation merits substantial benefits in PM emission reduction. Assuming a 5% pilot amount, a “once through” process has been modeled and a first law analysis (using practical isentropic efficiencies) demonstrates that this combined system can be operated with a reduction of between 5%–10% of the equivalent diesel efficiency. Significant quantities (∼30vol%) of hydrogen are introduced to the natural gas as a byproduct of the DME synthesis process. The corresponding increase in combustion efficiency must be validated by experiments to determine DME and H2 requirements for successful pilot ignition of the natural gas/H2 mixture.

Novel Natural Gas to Liquids Processes: Process Synthesis and Global Optimization Strategies

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Nationwide, Regional, and Statewide Energy Supply Chain Optimization for Natural Gas to Liquid Transportation Fuel (GTL) Systems

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SUSTAINABILITY EVALUATOR: Tool for evaluating process sustainability

“…In this approach, DME is produced in three different isothermal reactors by the following steps: steam reforming, methanol synthesis, and DME synthesis . In the steam reforming step, natural gas is reacted with steam with nickel or magnesium oxide acting as catalysts to produce synthesis gas as shown in Eq.…”