Opportunity for Cost Optimization Through Flowline Sharing and Using All in One Multi-Phase Flow Meter MPFM at Wellhead
Authors: Basloom S. M. , Kataria Ashwani. K. , AlSuwaidi M. H. , Constantini A. 
Published: November 2017

In order to find out the opportunities for cost saving, the focus must be directed to the main contributors in the overall cost. In Oil and Gas gathering facilities, one of the main contributors to the overall cost is how the gathering pipeline network is set up. Many field development options are available that depend on the nature of the development i.e. Pad design, Remote Manifolds Stations, and other designs that aim for cost saving. Pad design might be one of the best available options; however, it can be applied in the development of a green field gathering network, where a group of the wells are drilled in specific patterns. For the field where the wells are scattered, Pad design might not be the most cost-effective solution. The sharing of the flow lines is another practical approach that can be applied in, no matter, green or brown field gathering network development.

However, one of the main challenges is the loss of production during well testing. This loss is mainly due to shutting down of one well while testing the other. Several options have been studied to compare the current practice of well's tie-in and testing verses the optimized and innovative idea of the flow lines sharing with the consideration of "All-in-One" Multi-phase Flow Meter (MPFM) at the Well head for well testing. Option-1 in brief is to construct a number of new gathering stations and tie-in the wells via individual single flow lines to these stations, while the concept of Option-2 is to use the spare capacities in the existing flow lines and transfer lines to tie-in the new wells to the nearest and close by existing wells. The local MPFM's will be deployed on both new and existing wellheads. If NO spare capacities are available in the existing transfer lines between the gathering stations and central gathering station, then Option-3 is the best fit which is the construction of less number of gathering stations than Option-1 while adopting the concept of flow line sharing and having local MPFM's at the each of the well heads.

These options have been evaluated according to ADNOC four pillars comprising of people, performance, profitability and efficiency emphasizing on and without compromising the HSE and asset integrity. The importance of adequacy checks and maximizing the utilization of existing facilities is a "must do" in the current market condition in order to get the maximum return from what has been spent earlier.

The results showed that, sharing of the flow lines by combining the flow of two wells has a very high cost benefit verses having individual flow lines per well. The drawback of production losses will be recovered by the deployment of MPFM's at each individual wellhead that provides the well production test data all the time. Therefore, the optimized approach of Oil gathering network will enable the forthcoming projects to move forward with development and get more production with less investment.

Though sharing of flowlines with MPFM's at wellheads seems to be the best approach, its direct implementation poses certain challenges because of the current design of MPFM's that require infrastructure (such as power availability) constraints at remote wellhead locations. This paer highlights the need of industry to work and develop a design of MPFM's that minimizes or eliminates such constraints to make this technology widely acceptable in such applications.