A Multi-Parameter Optimization Model for the Evaluation of Shale Gas Recovery Enhancement

Abstract

Although a multi-stage hydraulically fractured horizontal well in a shale reservoir initially produces gas at a high production rate, this production rate declines rapidly within a short period and the cumulative gas production is only a small fraction (20-30%) of the estimated gas in place. In order to maximize the gas recovery rate (GRR), this study proposes a multi-parameter optimization model for a typical multi-stage hydraulically fractured shale gas horizontal well. This is achieved by combining the response surface methodology (RSM) for the optimization of objective function with a fully coupled hydro-mechanical FEC-DPM for forward computation. The objective function is constructed with seven uncertain parameters ranging from matrix to hydraulic fracture. These parameters are optimized to achieve the GRR maximization in short-term and long-term gas productions, respectively. The key influential factors among these parameters are identified. It is established that the gas recovery rate can be enhanced by 10% in the short-term production and by 60% in the long-term production if the optimized parameters are used. Therefore, combining hydraulic fracturing with an auxiliary method to enhance the gas diffusion in matrix may be an effective alternative method for the economic development of shale gas.

Formulation and Optimization of Monolithic Fixed-Dose Combination of Metformin HCl and Glibenclamide Orodispersible Tablets

“…ese findings were slightly different from previously observed findings in other studies which showed that as the PEG 6000 concentration increased, drug release also increased for immediate release tablets [27]. is limited effect of PEG 6000 on the drug release might be due to the fast disintegration nature of the tablets and micronized form of glibenclamide used in this study [28].…”

“…ODTs. e selection was based on the comparisons of several statistical parameters including the coefficient of variation (CV), multiple correlation coefficient (R 2 ), adjusted multiple correlation coefficient (adjusted R 2 ), and predicted residual sum of squares (PRESS), provided by Design-Expert ® software [28]. Accordingly, the quadratic model and linear model were selected for friability and disintegration time, respectively.…”

Effective Exploitation Potential of Shale Gas from Lower Cambrian Niutitang Formation, Northwestern Hunan, China

“…The initiation of hydraulic fractures and the stress distribution of shale reservoirs are also affected by the uniaxial compression strength (UCS) of shale, while cracks begin to extend when the stress intensity reaches or exceeds the fracture toughness of the shale [47,48]. The more organic matter content in shale with a lower UCS, the easier for cracks to initiate and extend forward during fracturing [49].…”

A Fully Coupled Numerical Model for Microwave Heating Enhanced Shale Gas Recovery

“…Current mainstream technologies available for commercial development of shale gas are horizontal drilling plus hydraulic fracturing, which can largely enhance reservoir permeability [2][3][4][5][6]. After hydraulic fracturing, the gas production rate is dramatically enhanced in the short term but this high production rate drops quickly in the longer term [7]. For conventional gas reservoirs, single hydraulic fracturing mainly generates great-scale fractures from the preexisting fractures.…”