Abstract
Gas Well Optimization implementations in the petroleum industry is taking on an important challenge as our industry moves into new frontier production areas such as deep water development and re-invigorated improved recovery operations in producing and abandon reservoirs. Today, high oil and natural gas prices dominate the energy fuels market, forcing companies to look into technologies that will efficiently produce and transport oil and gas to their customers. Attention to pipe performance in the recent past relied on conventional design values such as pipe strength parameters. The introduction of probabilistic evaluation of Oil Country Tubular Goods (OGCT) in the 1990s has provided a more focused approach to tubular strength design. Presently, strength optimization is not the only most cost-effective design concern. Current piping design is more concerned with the ability of pipes to transport fluids at a substantial reduced drag. This resistance to flow is caused mainly by inherent surface roughness due to pipe fabrication and/or corrosion products. A significant outcome in the reduction of surface roughness in pipes can help in optimizing deliverability of the production system. An application of a successful flow assurance program is the result of engineering and scientific knowledge integration, technological know-how, staff proficiency, and operability.
Our results are based on impact of surface roughness reduction as a result of utilizing internally coated pipes and newly developed alloys used in OCTG. Our approach to estimate the average surface roughness for modern pipes is based on using our new relative roughness tables and a graph (Farshad et al., 2006) in computer models showed a decrease in the pressure drop with an accompanying increase in the fluid throughput. The presenting case histories using the newly developed surface roughness values for internally coated and newly developed alloyed piping are discussed.
Computer models were used to apply the newly developed surface roughness graph and its application to simulate production results for two producing gas wells. Case histories are presented for the two gas wells located offshore Louisiana. TOPS and PIPEPHASE® 7.2 computer models were used to investigate the impact of changing the internal surface roughness of the tubing on production-performance (Simsci, 1999). Modeling results from one of the two Gulf of Mexico gas wells using different well production scenarios showed that gas flow rates increased by 24.5% when substituting a proprietary modified epoxy coated plastic tubing, and a 14.06% increase in flow rates for proprietary liquid phenolic coated production tubing over traditional bare carbon steel pipe. It is apparent that these results justify departure from existing pipe design practices.
