Photo: Aker Solutions

Norwegian duo adding new subsea concept to low carbon toolbox

Norwegian companies Aker Solutions and Seabed Separation have entered into a technology cooperation agreement  to promote a new subsea separation concept that is said to help reach Environmental Sustainability Goals (ESG).

The new concept, named the Dual Pipe Separator (DPS), is said to solve the challenges of high-cost field development, increasing water production and higher Environmental Sustainability Goals (ESG) requirements, the partners said.

The solution works in a way that well stream enters the gas harp which suppresses incoming energy and splits the liquids and gas, with gas being transported to the DPS oil outlet and commingled. The liquids, without free gas, having low velocity, less than 1.5 m/s enter the horizontal 6 pipe and form two-layer flow, oil on top and water below 

The two-layered flow enters the DPS inner pipe, which expands from 6 to 18, further reducing the velocity and the oil is, through large holes, guided out in the top and the water is guided to the lower part through similar perforation. The oil phase then leaves the top of the DPS, meets the gas, and is further transported in the downstream pipeline, while the clean water is removed for further treatment or reinjected.  

Inside the DPS an interphase controller monitors and maintain the correct water level, Aker Solutions said.

According to the company, subsea separation using the DPS system will give less backpressure to the reservoir, thereby giving higher production and recovery.  

“Adding the Dual Pipe Separator solution to the low carbon toolbox, gives us even more alternatives to increase the recovery factor on a field development for our clients,“ said Morten R. Pedersen, Senior Vice President of Subsea Engineering at Aker Solutions. 

The DPS system consists of a modularized unit with inclined pipe separators that is expected to give a stable flow and separation process, as well as increased oil recovery.   

The parties state that it is an enabler for efficient and profitable development of subsea fields and can be applied in deep water up to 3000 meters with a shut-in pressure of 350 bar. It is deployable for both greenfield and brownfield applications.