Test procedures for measuring exhaust emissions from natural gas transmission engines

This paper reports on the measurement of exhaust components from large natural gas transmission engines involves collection of the exhaust sample, transfer of the sample to the analytical instrumentation, measurement of individual component concentrations, and calculations of emission results in terms of mass, fuel specific, and brake specific rates. The major exhaust components measured include nitrogen oxides (NOx), total hydrocarbons (THC), carbon dioxide (CO2), carbon monoxide (CO), and oxygen (O2). Collection of the exhaust sample requires proper probe design and placement in the exhaust system. Transfer of the sample to the analytical instruments must maintain sample integrity from the point where the sample is removed from the exhaust stream to the point at which the sample enters the instrument for analysis. Various analytical techniques are used to measure the exhaust emission concentrations