The new high-performance demulsifiers and the (tetrakis (hydroxymethyl) phosphonium sulfate) THPS-based chemical have been trialed in order to eliminate the negative effects of naphthenic emulsions and scales. The field trials were fully executed in line with trial programs and proved to be successful. Field trials were executed in two operation modes – simultaneous injection of new demulsifiers with THPS-based chemical and only just demulsifiers. Based on the trial results, the effective chemical solutions for crude oil treatment at oil and gas production facilities on the continental shelf of the Russian Federation were found in conditions were naphthenic emulsions and sediments can be formed. The effective dosage rates of new demulsifiers are found to be in range from 20 to 60 ppm per based on production volume, KPI of chemicals are confirmed. The synergetic technology for offshore chemical injection was trialed and introduced as simultaneous continuous injection of a high-efficiency demulsifier with 20-60 ppm dosage rate and 100 ppm of special THPS-based reagent inlet to HP separator. The proposed chemical treatment program enables to stabilize oil treatment process, to improve quality of produced water and to reduce platform operations workload. It was proved that simultaneous injection of the demulsifier and THPS-based reagent leads to: a) reducing of high-molecular naphthenic acids volume in sediments found in platform’s process vessels; b) increasing of calcium content and phosphorus content in sediments, originating from organophosphorus compounds which are products of THPS decomposition interacting with calcium ions from produced water. Based on trial results new special production chemicals are recommended for injection at Sakhalin Energy production facilities.
References
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