Production performance of multiple approaches for stimulating the layered hydrate reservoir with high permeability under horizontal well systems.

Implementing efficient measures to increase production is crucial for the commercial development of hydrate. Currently, several potential stimulation methods, including well type optimization, depressurization amendment and reservoir reconstruction, have been proposed. However, most studies tend to focus on a single measure, and there are few reports on the stimulation performance under multiple means. Therefore, our study concentrated on constructing production models for simplified layered hydrate reservoirs in the Nankai Trough using four different horizontal well systems. The production enhancement resulting from aggressive depressurization and various well patterns were explored. Additionally, the production performances under conditions of burden sealing and reservoir permeability enhancement were further evaluated respectively. Lastly, the common impact of employing both burden sealing and reservoir permeability enhancement was assessed. The prediction results show that: (i) Decreasing the bottomhole pressure effectively enhances gas recovery and can be combined with other techniques for better expectation; (ii) There exists an optimal burden sealing ratio that maximizes gas production while increasing the permeability enhancement ratio consistently stimulates gas recovery; (iii) Both single and dual well systems, assisted by aggressive depressurization, are expected to achieve commercialization whereas the triple well pattern is unfavorable for achieving a significant increase in yield. • Stimulation performance of multiple means for NGH was systematically evaluated. • The optimal sealing ratios under different situations were firstly obtained. • Effects of well type, production pressure and permeability increase were studied. • Some promising schemes reaching commercial standard were suggested. [ABSTRACT FROM AUTHOR]