SYNERGETIC EFFECT OF A DRAG REDUCER AND PIPELINE INTERNAL COATING ON CAPACITY ENHANCEMENT IN OIL AND GAS PIPELINES: A CASE STUDY

A case study of a 20-inch diameter gas transmission pipeline assesses theoretically how the synergetic use of pipeline internal coating and drag reducing agent increases the flow rate of a pipeline and its impact on the pipe internal friction. The American Gas Association (AGA) equation and Modified Colebrook-White equations were both used to estimate the capacity of the pipeline in its existing state, after internally coating and after injecting a drag reducing agent in the internally coated pipeline. By means of both AGA equations and Modified Colebrook–White equations, it was observed that Internal coating with surface roughness of 0.0045mm can increase the pipeline capacity (flowrate) by up to 22% for gas pipeline systems. Also, the synergetic use of a pipeline internal coating such as polyamide epoxy or solvent free epoxy and a Polyacrylamide drag reducing agent can increase the pipeline capacity (throughput) above 115.53% for GNGC gas pipeline systems. The analysis shows that synergetic use of internal coatings and drag reducers increases the capacity of gas pipelines and is economically justified with a typical payback period of three years.