Increasing water-cuts is inevitable for mature oil fields in which water flooding is used to achieve higher recovery targets. As water rates increase, significant investments are required to debottleneck water handling facilities and pipelines. This paper summarizes a detailed assessment to find the benefits of implementing a separation process to improve water separation efficiency. Inline Water Separator is considered here to optimize capital expenditures, building on the experience of a field demonstration of the technology.
A prototype pilot plant was installed demonstrating an Inline Water Separator technology. Using a set of different inlet conditions. The technology was able to achieve +70-80% separation efficiency and deoiled the water to a maximum oil-in-water concentration of 35 ppm reaching lower than the accepted oil in water discharge criteria for reinjection (Zhang et all). Building on the success of the prototype, a suggested roadmap was studied to expand the testing of the technology at further harsher conditions with heavier crude grades and test alternative Inline Water Separation Technologies. A business case assessment was also conducted to determine the feasibility of the Inline Water Separator solution versus conventional water handling upgrades.
Alternative Inline Water Separator technologies were also looked at as modularly designed skids that are easily transportable. The skids can be installed at different locations such as remote well manifolds or immediately pre-inlet processing facility. A technical and economic assessment of Inline Water Separator was conducted. It was found to be an economically attractive alternative to implementing conventional extensive oil-water separation, crude oil desalting, water deoiling & injection and pipeline network upgrades. The benefit of IWS besides reduction in capital expenditures, enhanced oil-in-water and a reduced overall energy and chemical consumption also results in reduced operating expenditures. When IWS is installed at the well manifold the stud shows a that the water rate will be reduced in the trunkline downstream the inline water separator and therefore a reduce the backpressure on the well will accrue, which can potentially increase the oil rate. Another benefit that was found, this design will potentially enhance distribution of field water injection as separated water from the inline water separator can be rerouted to another desired location or flank.
The study of the Inline Water Separator technology portfolio expansion is highly recommended as a strategy to optimize capital expenditures to manage increasing produced water rates. The paper provides the alternative solutions, potential benefits and business case assessment to justify potential deployment.