The role of Earth Cover and Compaction Level on the Natural Gas Leakage rate from micro holes in an underground pipeline

Abstract

The pipeline is the most economical and effective way of transporting Natural Gas (NG), but the existing of a leak in the pipeline makes it dangerous and prone to the Unaccounted for Gas (UFG). Since the detection of a leak and then its rectification takes time. Due to which a large amount of natural gas is escaping from the leak which not only contributes to UFG, environmental pollution but the excessive amount of NG in the workplace can cause accidents. The aim of this research work is to quantify the leakage rate due to micro-hole in the medium pressure NG pipeline used in the distribution network and the reduction of leakage rate due to the earth cover and compaction level of the soil. For this purpose, an experimental rig was designed to study the leakage rate in above ground and underground NG pipeline. It is observed that the leakage rate significantly reduces due to the earth cover on the leaky pipeline and the increase of relative compaction of the soil which further reduces the UFG, environmental and economic loss. An average of 28.8% and 52.5% reduction in leakage rate were observed when Gravely clay was compacted to a relative compaction of 55% and 71% respectively.