Gas Adsorption and Controlling Factors of Shale: Review, Application, Comparison and Challenges

  • PDF / 2,393,623 Bytes
  • 22 Pages / 595.276 x 790.866 pts Page_size
  • 50 Downloads / 189 Views

DOWNLOAD

REPORT


Review Paper

Gas Adsorption and Controlling Factors of Shale: Review, Application, Comparison and Challenges Asadullah Memon,1,2 Aifen Li,1,4 Bilal Shams Memon,2 Temoor Muther,2 Wencheng Han,1 Muhammad Kashif,3 Muhammad Usman Tahir,1 and Imran Akbar1 Received 21 May 2020; accepted 29 August 2020

The selection of an optimized gas adsorption model is a quantitatively challenging task when characterizing shale gas reservoirs because every model has its own assumptions and mechanisms. In addition, excess when converting different models to absolute gas adsorption is reported in the literature, which differs due to variations in adsorbed phase density or volume. The roles of controlling factors change under various conditions and consequences, and it is hard to comprehend shale storage and production sources. Quantifying the contribution of adsorbed and absorbed gases to total gas storage is also challenging despite existing advanced techniques. This paper reviews gas adsorption in the light of applications, comparisons and challenges along with shale controlling factors, and it provides a better opportunity to comprehend shale storage and platforms to investigate further mechanisms of shale gas storage. It is revealed in this review that several crucial factors are found in shale that control and affect the gas adsorption capacity. Kerogen swelling and pore shrinkage, kerogen maturity, gas type and moisture content greatly influence gas adsorption capacity. The measurement of true adsorbed and bulk amount, selection of an optimized gas adsorption model, proper investigation of shale controlling factors, and accurate measurement of adsorbed and absorbed gases may enhance the accuracy of resource assessment and production performance predictions. KEY WORDS: Shale storage, Adsorption/sorption models, Controlling factors, Resource assessment, Production performance.

INTRODUCTION

1

School of Petroleum Engineering, China University of Petroleum (East China), Huangdao District, Qingdao 266580, Shangdong Province, PeopleÕs Republic of China. 2 Department of Petroleum and Natural Gas Engineering, Mehran University of Engineering and Technology SZAB Campus, Khairpur Mirs, Sindh, Pakistan. 3 College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, PeopleÕs Republic of China. 4 To whom correspondence should be addressed; e-mail: [email protected]

Shale is an unconventional natural gas reservoir with complex physical properties, exhibiting extremely low permeability and low porosity (Xu et al. 2015; Liu et al. 2016) as well as various pore networks and transport processes through which gas flows (Mingyao et al. 2018). The gas stored in this type of reservoir is in three forms, i.e., free, adsorbed and absorbed/dissolved gas. Pores as well as natural/ induced fractures store free gas, whereas both organic matter and inorganic matrices store adsorbed gas (i.e., clay mineral and kerogen), but only inorganic matter stores absorbed gas (Yang et al. 2015).

Ó 2020 International Association