Fit and Forget
Unfortunately most multiphase pumps do not function well at high GVF values under continuous operation, whilst the Wellcom Boost system does not have this limitation. For practical reasons, the GVF should be below 60% for some types of multiphase pumps. This does not mean that they do not work above 60% GVF but their size, cost, power requirement and capacity increase significantly.
When GVF is of a higher value, often a liquid recycling line is needed for some types of MP pumps in order to keep the inlet GVF within an acceptable range. This is achieved by means of a dedicated separator at the discharge side of the pump. This is an added complexity of the system. The use of multiphase pump depends on the availability of high electric power at the location. Many satellite and wellhead platforms lack the power needed for multiphase pumps.
Throughtout the world most multiphase pumps do not tolerate severe slugging and extreme flow fluctuations. In this case a flow conditioning device in form of a storage vessel may be needed for some pumps to regulate the fluctuations. This is also an added complexity
Whereas the Wellcom Boost relies on a source of HP gas to boost the pressure of the gas phase. Therefore its range, the number of LP wells it can handle, and its viability is dependent on the pressure and the amount of HP gas available.
The Wellcom Boost has a gas–liquid separation system, but the MP pumping system does not require gas–liquid separation. It is worth noting that the separation system (I-SEP) used for Wellcom Boost system is a compact unit with a small foot print and is simple to operate. Also the separator is not required to operate with great efficiency as the jet pump can tolerate some liquid in the separated LP gas phase which it receives, and the booster pump can also tolerate a small amount of free gas by choosing a range of positive displacement type pumps which can tolerate free gas in the liquid phase.
In the case of Wellcom Boost, if the separated liquid can be directed to an existing 2nd stage separator, the need for a booster pump system will be eliminated. This will lead to considerable saving and simplification of the Wellcom Boost system.
In the case of Wellcom Boost, HP gas used as the motive flow, combined with the LP fluids, increases the flow throughput of the export piping system. In this case the downstream export piping/process equipment may become bottlenecked to handle the increased flow and the pipeline pressure will increase. This condition can be met as in most cases the jet pump will operate against the higher export line pressure but will enable the producing wells to be exposed only to the lower pressure which the jet pump generates.
Also see Benefits.