L51802 Cost Effective Leak Mitigation at Natural Gas Transmission Compressor Stations

A reciprocating compressor facility with seven to eight compressors could be expected on average to develop new leakage at standard components of 2,700 Mcf/yr. Approximately 75% of the total new leak volume occurs at compressor components even though they only comprise approximately 30% of the total components at a site. The cost of follow-up surveys can be reduced by focusing on the compressor areas. A centrifugal compressor facility with two compressors could be expected to develop new leakage at standard components of approximately 100 Mcf/yr. The results are indicative of the fact that these facilities do not experience the type of vibrational stresses typically encountered at reciprocating compressor stations.

This report describes a cooperative study sponsored by PRCI, GRI, and the U.S. Environmental Protection Agency (EPA) to determine the most cost effective ways to mitigate leaks at natural gas compressor stations. Leak rate measurements were initially made at thirteen compressor stations starting in September of 1995 until the end of 1997. Ten of these sites were selected for four quarters of surveys. This report presents the emission factors for natural gas compressor stations, the trends in leak rates over time, and a cost benefit analysis of leak mitigation.