Home » Expertise » Production Operations » HOGS—Assessment of Heavy Oil Gathering System Alternatives

HOGS—Assessment of Heavy Oil Gathering System Alternatives

Status: Phase I, II, & III completed. - The objective of the Heavy Oil Gathering Systems (HOGS) Joint Industry Project (JIP) is to identify processes that are cost competitive with trucking for transporting produced fluid from a heavy oil well to a battery.

Phase I of the HOGS JIP, launched in 1998, evaluated the technical and economic viability of various gathering system alternatives compared to the conventional use of trucks. The evaluation considered approximately 1,800 combinations of equipment configurations and operating conditions to cover a wide range of heavy oil applications. This work concluded that pipelines could be technically feasible and economically viable in a wide range of applications.

Phase II of the project focused on developing a software tool to help evaluate the transient operating conditions in a heavy oil gathering line following a shut down and subsequent re-start. The resulting software, HOGS®, takes into account the transient heat exchange with the surroundings and includes models for a variety of oil-water flow regimes such as emulsion and core annular flow.

Phase III consisted of a series of flow experiments in an existing 152 mm flow line in the Plover Lake heavy oil field in Saskatchewan, Canada which is operated by Nexen. Mass flow meters were used to independently measure the flow rate of separate water and oil supplies that were combined to achieve various water cuts. Upstream and downstream pressures and temperatures were also monitored to determine the pressure and temperature drop through the 300 metre test section.

Oil viscosities during testing ranged from 550 cp to over 20,000 cp. Water cuts as low as 5% were imposed in some cases to determine the limits of complex, low-water cut flow regimes similar to core annular flow. Repeated shut down events were also used to evaluate what was required to re-initiate these flow regimes when the line was restarted.

Phase IV of the project may include investigating the key issues of sand transportation in complex, multiphase flow regimes and developing cost effective methods to clean settled sand from long gathering lines.

Contact: Peter Kis, Manager, Drilling & Completions