Improving efficiency in the petroleum industry
Frictional pressure drops or drags are responsible for energy losses and limitations in the throughput of oil pipelines. Injecting long-chain polymers in oil pipeline networks can significantly reduce this problem. This, however, is not a widely used technique, due to the lack of design and operation knowledge on an industrial scale. The main objective of the AESOP project was to investigate the potential of Drag Reducing Agents (DRAs) to reduce the energy consumption and to increase the transport capabilities of oil pipeline networks. DRAs are long chain hydrocarbon polymers, which are injected into the oil to reduce energy loss due to turbulence and friction. In the context of the AESOP project the effect of DRAs on the metering equipment was analysed under different operating conditions in order to determine the most energy efficient method of removing this influence. Tests were carried out based on comparisons between a counter at the beginning of the line located before the injection point and a second one at the end. Each test was composed of a series of different stages always starting with a reference comparison of both counters without DRA injection. The use of a control valve to create a pressure drop before the downstream metering equipment has been seen as a solution to the deviation effect. A pump is another way to remove the effect but should be used only if after the pump there is another section of pipeline, which does not need DRA. This is due to the fact that the pump requires energy to work and that energy is lost in case of delivery just after this equipment. The results of the project may lead to optimal design and operation of oil pipelines using DRA as well as an assessment of the benefits obtained by the technique. The resultant gain in energy will be extremely rewarding to the petroleum industry.