Cost-Effective Scheduling of Modular Equipment in Shale Gas Gathering Systems with Hydraulic Considerations

The scheduling of modular equipment (ME) in gathering systems is related to not only node pressure but also the production of shale gas. As shale gas continues to be extracted, its production decreases, leading to continuous changes in the load rates of ME and various operating conditions. Although considerable research exists on the scheduling of ME, multiple types of ME and incorporating the hydraulic characteristics of the pipeline network are less common. For shale gas gathering system (SGGS), this paper has established a multitype ME scheduling optimization model coupled hydraulic characteristics (MMESH-model). The objective function of the model is to minimize total equipment cost, and the model is subject to the following constraints: pressure, compressor, well and platform throttling, node pressure balance, flow balance, nonpressurized equipment handling capacity, multitype ME scheduling, and equipment utilization. A case study is discussed to prove the proposed model. The scheduling scheme of the ME is obtained, which is different from that of the actual site. In the early stages of production, platform pressures could reach 9.87 MPa, whereas the station requires an external transmission pressure of 5.91 MPa. A platform pressure of 6.046 MPa suffices in the first year, eliminating the need for a compressor. Moreover, the separator is relocated 11 times, the dehydrator is not relocated, and the compressor is relocated eight times. In addition, the cost analysis shows that the procurement and operating costs of ME are much higher than other costs. As a result, a new method for optimizing ME in SGGS with coupled hydraulic calculation is developed, and this method has some guiding implications for SGGS operation and production.