Remote Sensing Natural Gas Leak Detector with Novel Optical Filter. Final Report,November 1990-August 1993

摘要

Each year, more than 100,000 miles of street mains are surveyed for gas leakswith vehicle-mounted gas detection systems. With state of the art (SOA) detection systems, vehicles must travel slowly (2-7 MPH). As a result, the operation in labor-intensive. In initial feasibility studies, a new vehicle-mounted gas leak detection system has demonstrated successful leak detection at vehicle speeds of 20 MPH or more. With these operating conditions, productivity increases of 20-50% or more may be possible. Based on the infrared absorption of methane, the front-mounted detection system performed successfully under a variety of environmental conditions, including rain, and snow, with gas leaks, both simulated and real world. The Concept Evaluation Unit (CEU) was easily able to detect gas concentrations as low as 1 ppm above the universal methane background. In direct performance comparisons with an SOA-equipped vehicle, the CEU performed flawlessly, reporting the presence of gas over a controlled range of gas leak rates and vehicle speeds. Under the same conditions the SOA vehicle incurred both false positives and negatives.