Industrial Test and Application of Drag Reducer in Sudan GNPOC Crude Oil Pipeline

The drag reducer, EP-W203, was industrially tested and applied in a long segment of Sudan GNPOC (Greater Nile Petroleum Operating Company) crude oil pipeline. From July 29th to August 3th in 2001, between PS#1 and PS#3, which totals 547km in length, a single point of DRA injection at PS#1 was tested. With an average DRA injection concentration of about 23.4 ppm, 8.28% of drag reduction and 5.09% of throughput increase was gained. It is indicated that 70–80% of drag reduction capacity was still remained after 237 kilometers of pipe wall shear from PS#1 to PS#2. But after severe local shear (without pump shear) during by passing PS#2 process, the DRA almost lost its efficiency. On Dec., 30th, 2001, two points DRA injection test at PS#1 and PS#2 were performed, with injection concentration about 25ppm individually and a total of 12% throughput increase was realized. Since then, routine industrial application of DRA injection at two points were commenced. During the application of DRA since the end of July in 2002, the pipeline throughput suddenly decreased for about 4.32%. Even adding with a third DRA injection point at BV5 was no effect to the pipeline throughput. Research and analysis indicated that due to the change of oil source and the increase of crude viscosity, and the effect of environmental condition in raining season as well, the Reynolds number between PS#2 and PS#3 decreased to lower level, which reduced the function and effect of the Drag Reducer.