Studies On The Stability And Treatment Agent Of Slop Oil From Weak Alkaline ASP Flooding

With ASP flooding being widely put into field trial, a large amount of slop oil is being produced. It is necessary to develop the recovery and treatment technology of slop oil in order to eliminate or reduce the damage of environmental pollution and waste of resources. In Daqing oilfield slop oil is simply blended into fresh produced fluid for recovery and treatment. Though very simple and cost-effective, the slop oil recovery process often leads to upset of production stations as the mechanical impurities in the slop oil tends to deposit in the boundary of oil phase and water phase to form a rag layer in electrical treaters. This can bring damage to oil production.Starting with composition analysis and measurements of the physical properties of weak alkaline ASP Flooding, The effects of ASP agents, resin, asphaltene and solid particles on the stability of the slop oil produced by weak alkaline ASP Flooding were analyzes. ASP agents, resin and asphaltene can stabilize slop oil well. The solid particles are the main factor that causes and stablizes the rag layer during slop oil thermal settling by forming solid net on the surface of droplets and steric hindrance to their coalescenceTreatment agents and a treatment process for the slop oil from weak alkaline ASP Flooding in Daqing oilfield were developed according to the stability characteristics of the slop oil. The main points of a preferred treatment scenario include dosage of a compound demulsifier at 50mg/kg, dosage of an auxiliary agent at 700mg/kg, water blending ratio at 40%, settling temperature at 70℃and retention time in the range of 2h to 8h. The treated oil almost meets pipeline spec and can be recovered to production station for further treatment. The chemical cost of slop oil treatment is only 3.1RMB/ton.