Development of the Cooper-Bessemer CleanBurn™ Gas-Diesel (Dual-Fuel) Engine

Abstract

NOx emission legislation requirements for large-bore internal combustion engines have required engine manufacturers to continue to develop and improve techniques for exhaust emission reduction. This paper describes the development of the Cooper-Bessemer Clean Burn™ gas-diesel (dual-fuel) engine that results in NOx reductions of up to 92 percent as compared with an uncontrolled gas-diesel engine. Historically, the gas-diesel and diesel engine combustion systems have not responded to similar techniques of NOx reduction that have been successful on straight spark-ignited natural gas burning engines. NOx levels of a nominal 1.0 g/BHP-h, equal to the spark-ignited natural gas fueled engine, have been achieved for the gas-diesel and are described. In addition, the higher opacity exhaust plume characteristic of gas-diesel combustion is significantly reduced or eliminated. This achievement is considered to be a major breakthrough, and the concept can be applied to both new and retrofit applications.