Engineering Commons^™

The Hole Sealing Technology Of Solid-Liquid Materials With Three Pluggings And Two Injections For Gas Extraction Hole In The Coal Mine, Shiyao Yu, Xianbo Su, Jinxing Song, Qian Wang, Zhenjiang You

Research outputs 2022 to 2026

The sealing quality of the gas extraction holes determines the extracted gas concentration. Based on this, the paper reveals the basic principle of hole sealing by analyzing the gas leakage mechanism of the borehole. The hole sealing technology of solid-liquid materials with three pluggings and two injections for the gas extraction hole is proposed, and the hole sealing device and material are developed. Through testing the granularity distribution of the solid material, as well as the surface tension and contact angle of the slurry, the hole sealing material that can meet the requirements of accessible, sticky, and anti-deformation is selected. …

Hydrogen Diffusion In Coal: Implications For Hydrogen Geo‐Storage, Alireza Keshavarz, Hussein R. Abid, Muhammad Ali, Sefan Iglauer

Research outputs 2014 to 2021

Hypothesis

Hydrogen geo-storage is considered as an option for large scale hydrogen storage in a full-scale hydrogen economy. Among different types of subsurface formations, coal seams look to be one of the best suitable options as coal’s micro/nano pore structure can adsorb a huge amount of gas (e.g. hydrogen) which can be withdrawn again once needed. However, literature lacks fundamental data regarding H₂ diffusion in coal.

Experiments

In this study, we measured H₂ adsorption rate in an Australian anthracite coal sample at isothermal conditions for four different temperatures (20 °C, 30 °C, 45 °C and 60 °C), at …

Hydrogen Adsorption On Sub-Bituminous Coal: Implications For Hydrogen Geo-Storage, Sefan Iglauer, Hussein Abid, Ahmed Z. Al-Yaseri, Alireza Keshavarz

Research outputs 2014 to 2021

Hydrogen is a clean fuel that can potentially revolutionize the energy supply chain and decarbonize fuel consumption. However, a key hurdle that needs to be overcome before a full-scale hydrogen economy can be established is hydrogen storage which is currently the main limitation. Here, we propose that hydrogen gas can be stored in underground coal seams, where it adsorbs on the coal surface. However, currently, no hard data related to such a procedure exists. We, therefore, demonstrate experimentally that significant amounts of hydrogen gas can be stored via this route. Hydrogen adsorption capacities reached 0.6 moles H₂/kg of …

Drastic Enhancement Of Co2 Adsorption Capacity By Negatively Charged Sub-Bituminous Coal, Hussein R. Abid, Stefan Iglauer, Ahmed Al-Yaseri, Alireza Keshavarz

Research outputs 2014 to 2021

Climate change is a key problem of the 21st century. Climate change is mainly caused by anthropogenic CO₂ emissions, and one solution to this problem is to capture and store CO₂ in deep coal seams, where it is immobilized by adsorption to the coal surface. Here we propose to modify the coal with methyl orange (MO), a typical dye that is also a major pollutant of the hydrosphere and removed thereby. Thus, raw and MO-modified coals were characterized to investigate their thermal stabilities, textural properties, carbon contents, surface characteristics, and CO₂ adsorption on the coal samples was …

Stable Dispersion Of Coal Fines During Hydraulic Fracturing Flowback In Coal Seam Gas Reservoirs - An Experimental Study, Faisal Ur Rahman Awan, Alireza Keshavarz, Hamed Akhondzadeh, Sarmad Al-Anssari, Ahmed Al-Yaseri, Ataollah Nosrati, Muhammad Ali, Sefan Iglauer

Research outputs 2014 to 2021

In subterranean coal seam gas (CSG) reservoirs, massive amounts of small-sized coal fines are released during the production and development stages, especially during hydraulic fracturing stimulation. These coal fines inevitably cause mechanical pump failure and permeability damage due to aggregation and subsequent pore-throat blockage. This aggregation behavior is thus of key importance in CSG production and needs to be minimized. Consequently, such coal fines dispersions need to be stabilized, which can be achieved by the formulation of improved fracturing fluids. Here, we thus systematically investigated the effectiveness of two additives (ethanol, 0.5 wt % and SDBS, 0.001 and 0.01 wt …

Low-Cost Carbon Fibre Derived From Sustainable Coal Tar Pitch And Polyacrylonitrile: Fabrication And Characterisation, Omid Zabihi, Sajjad Shafei, Seyed Mousa Fakhrhoseini, Mojtaba Ahmadi, Hossein Ajdari Nazarloo, Rohan Stanger, Quang Anh Tran, John Lucas, Terry Wall, Minoo Naebe

Research outputs 2014 to 2021

Preparation of high-value pitch-based carbon fibres (CFs) from mesophase pitch precursor is of great importance towards low-cost CFs. Herein, we developed a method to reduce the cost of CFs precursor through incorporating high loading of coal tar pitch (CTP) into polyacrylonitrile (PAN) polymer solution. The CTP with a loading of 25% and 50% was blended with PAN and their spinnability was examined by electrospinning process. The effect of CTP on thermal stabilization and carbonisation of PAN fibres was investigated by thermal analyses methods. Moreover, electrospun PAN/CTP fibres were carbonised at two different temperatures i.e., 850 °C and 1200 °C and …

Experimental Study Of Supercritical Co2 Injected Into Water Saturated Medium Rank Coal By X-Ray Microct, Yihuai Zhang, Maxim Lebedev, Hongyan Yu, Stefan Iglauer

Research outputs 2014 to 2021

Carbon dioxide geosequestration into deep unmineable coal seams is a technique which can mitigate anthropogenic greenhouse gas emissions. However, coal composition is always complex, and some minerals such as calcite chemically react when exposed to the acidic environment (which is created by scCO2 mixing with formation water). These reactive transport processes are still poorly understood. We thus imaged a water-bearing heterogeneous coal (calcite rich) core before and after scCO2 injection in-situ at high resolutions (3.43 µm) in 3D via X-ray in-situ microCT flooding system. Indeed, the calcite-coal mixed layer was partially dissolved, and absolute porosity and connectivity significantly increased. We …