Article
Construction & Building Technology
Zhaoheng Guo, Jingjing Xu, Zhenhai Xu, Jianming Gao, Xiaoliang Zhu
Summary: This study investigated the characteristics of coal gangue (CG) under different calcination conditions and its effects on cement paste and mortar. Results showed that CG can be used as supplementary cementitious material under specific calcination conditions, but calcination temperature, holding time, and cooling mode have important effects on its reactivity.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Energy & Fuels
Junjian Zhang, Chongtao Wei, Chengjin Zhao, Tao Zhang, Guanwen Lu, Mingjun Zou
Summary: The research finds that the reduction rate of surface free energy changes with increasing adsorption pressure, while increasing temperature leads to a decrease in adsorption capacity. High rank coal samples are more sensitive to temperature changes. Micro-pore structure has a significant impact on adsorption capacity.
Article
Environmental Sciences
Leipeng Liu, Junjie Yang, Yingfei She, Shenghua Lv, Zhen Yang, Pan Hu
Summary: This work investigated the use of coal gasification slag (CGS), a solid waste product in the coal chemical industry, as a supplementary cementitious material to prepare foam concrete (CGS-FC). The influence of CGS content and water-binder ratio on pore structure, mechanical, and thermal properties was studied. The results showed that the CGS content and water-binder ratio directly affected the flowability of the slurry and the internal pore structure of the specimens after molding. A CGS-FC with a compressive strength of 6.89 MPa, thermal conductivity of 0.24 W/m K, and a bulk density of 867 kg/m³ was successfully produced with a CGS content of 30% and water-binder ratio of 0.5. The utilization of CGS in foam concrete production was found to have recycling efficiency and environmental benefits.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Engineering, Geological
Ting Ai, Shiyong Wu, Ru Zhang, Mingzhong Gao, Jifang Zhou, Jing Xie, Li Ren, Zhaopeng Zhang
Summary: The study showed that as the water soaking time increased, the pore sizes in coal expanded and new pores developed, leading to changes in mineral composition and structural characteristics. The mechanical properties and ultrasonic wave velocity of coal decreased with increasing water-soaking time, and could be expressed by exponential functions.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Energy & Fuels
Xianfeng Liu, Xueqi Jia, Yue Niu, Baisheng Nie, Chengpeng Zhang, Dazhao Song
Summary: Liquid CO2 phase change fracturing (LCPCF) is an effective method for stimulating coal reservoirs and improving gas drainage efficiency in low-permeability coal seams. The study quantitatively analyzed the changes in coal mechanical properties and permeability before and after LCPCF treatment using low pressure CO2/N2 adsorption, CH4 permeability measurements, and UCS tests. The results showed that LCPCF treatment led to increased axial peak strain and ductile failure in the coal. The UCS and elastic modulus were reduced, and the pore structure was altered after LCPCF treatment. The gas permeability of the coal was enhanced, and a large number of new fractures were generated, facilitating gas flow in the coal seams.
Article
Green & Sustainable Science & Technology
Huajian Li, Zhen Wang, Ruru Sun, Fali Huang, Zhonglai Yi, Zhengcheng Yuan, Jiaxin Wen, Lin Lu, Zhengxian Yang
Summary: The study aims to investigate the feasibility of stone powders as a partial replacement for cementitious materials. Results showed that limestone and tuff powders can shorten setting time, while granite and quartzite powders can prolong setting time. Mortars blended with quartzite powder displayed significantly improved compressive strength with increasing specific surface area of the stone powders.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Energy & Fuels
Yujin Qin, Kan Jin, Fuchao Tian, Weiwei Su, Shaokui Ren
Summary: Coal and gas outburst, a catastrophic mining hazard, is closely related to igneous intrusion. Ultrathin igneous sill intrusion significantly changes the physical properties of coal, increasing its metamorphic grade and altering its thermal evolution zone. The moisture, ash contents, and gas desorption property of coal can be used as signs for detecting small-scale igneous intrusion and as early warning indicators for outburst prevention.
Article
Energy & Fuels
Nian Si, Gaofeng Liu, Jia Lin, Ping Chang, Xiaoming Wang, Zhen Zhang, Huan Liu
Summary: This study investigates the effects of carbon disulfide (CS2) extraction on nanopores of anthracite samples. Various pore measurement techniques were employed to analyze the changes in nanopore structure and fractal characteristics. The results indicate that CS2 extraction leads to an enlargement of macropores and a reduction in their fractal dimension, a reduction in the size of mesopores but an increase in their volume, area, and fractal dimension, and an enlargement of micropores but a reduction in their volume, area, and fractal dimension. These effects are beneficial for enhancing coalbed methane transport and provide a theoretical basis for the chemical reservoir stimulation technique with CS2 extraction.
Article
Construction & Building Technology
Tao Luo, Yu Yi, Qiang Sun, Leo Gu Li, Liyun Tang, Cheng Hua
Summary: In this study, molybdenum tailings were used as a replacement for cement or fine aggregate to produce molybdenum tailings concrete (MTC) in order to reduce land occupation and environmental pollution. The workability and mechanical properties of MTC were investigated, and the internal pore structure and micro-morphology were analyzed. The results showed that a replacement rate of 10% yielded the optimum performance for MTC, and changes in pore structure affected the strength of the concrete.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Energy & Fuels
Minghao Yi, Yuanping Cheng, Chenghao Wang, Zhenyang Wang, Biao Hu, Xinxin He
Summary: The hydrochloric acid treatment significantly reduced the content of minerals and volatile matter in coal, which increased the porosity and pore connectivity of coal. The role of minerals in pores of different sizes varied, affecting the evolution of coal pore structure.
Article
Construction & Building Technology
Xiuhao Li, Rentai Liu, Shucai Li, Chunyu Zhang, Jia Yan, Yankai Liu, Xuebing Sun, Peisen Su
Summary: This paper investigated the properties and mechanism of grouting slurry and hardened paste body exposed to seawater using the grouting method to maintain the cracks of subsea tunnel lining concrete. The self-healing capacity was achieved by incorporating Urea-Formaldehyde/Epoxy (UF/E) microcapsules in the grouting materials. The results showed that the microcapsules had a negative effect on the mechanical properties and porosity, and the self-healing capacity varied with the dosage and pre-damage level.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Energy & Fuels
Chunshan Zheng, Jinting Li, Sheng Xue, Bingyou Jiang, Bingjun Liu
Summary: Chemical solvents can enhance the conductivity of coal reservoir and promote efficient methane extraction. Acidification and THF treatment can affect the coal's chemical structure parameters and main functional groups, as well as the fractal dimensionality and pore structure characteristics. The results show changes in the absorption peaks and content of various components in coal after extraction and acidification. Acidification treatment and THF extraction also result in variations in pore sizes and the distribution of different types of pores in coal samples.
Article
Energy & Fuels
Lei Qin, Xian Zhang, Jun Matsushima, Bin Zhou, Peng Liu, Ruizhe Wang, Siheng Lin
Summary: This paper characterizes the porosity and pore throat structure of different coal grades (lignite, bituminous coal and anthracite) under liquid nitrogen fracturing cycles by testing the T2 and T1-T2 sequences. The results show that the total pore space of A, L and B is arranged in descending order according to the initial state. The internal porous throat distribution of lignite and anthracite coal samples is wider. With the increase of the number of fracturing cycles, the internal pore space of the three coal grade coal samples has been improved, of which lignite has the largest lifting rate; The internal porous throat distribution of L coal samples was reduced by 0.97%. The internal pore space of B and A coal samples increased by 34.62% and 6.33%, respectively, the pore-throat distribution increased by 28.96% and 16.98%, respectively.
Article
Environmental Sciences
Ping Zhang, Shifeng Tian, Song Ren, Fei Wu, Jie Chen, Longhao Ma
Summary: This study investigated the pore characteristics and mechanical properties of sandstone under different high temperatures and acidic solutions. The results showed that high temperature and acidic solutions significantly affected the pore structure and mechanical properties of sandstone, and their effects differed in each stage. The pore structure of sandstone showed a close linear relationship with mechanical properties, indicating that microstructural changes affected macroscopic mechanical properties.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Energy & Fuels
Yingquan Zhai, Yunbo Li, DangYu Song, Jienan Pan
Summary: Coalbed methane (CBM) is a renewable and green energy source with its production capacity limited by gas diffusion efficiency in coal. This study investigated the diffusion characteristics of coal samples with different metamorphism degrees using various gas adsorption experiments. The analysis revealed the influence of gas type, pore structure, and coal sample size on the gas diffusion coefficient, and discussed the synergistic control effect of these factors on diffusion. The research findings have significant implications in understanding gas transport in the coal matrix and formation of coalbed methane.
Article
Engineering, Chemical
Yongxiang Wu, Nguyen Thi Hong Nhung, Deqian Zeng, Nengneng Luo, Akira Otsuki, Gjergj Dodbiba, Toyohisa Fujita
Summary: This study proposed a novel method for synthesizing flower-like vaterite calcium carbonate using nanobubble-containing ethanol and water mixed solution as the solvent and discussed the formation mechanism of vaterite with different shapes. The synthesized vaterite has significant practical interest in the integrated treatment of wastewater contaminated by heavy metals with effective Cd(II) removal, providing a promising field for studying heavy metal and pollutant adsorption in the liquid phase.
ADVANCED POWDER TECHNOLOGY
(2024)
Article
Engineering, Chemical
Jian Gong, Lipo Cheng, Ming Liu, Jie Jiang, Xiaoduo Ou
Summary: This study investigates the effects of particle shape on the collapse of granular columns using the discrete element method. The results show that particle shape has a significant impact on deposition morphology, energy evolution, and mechanical coordination number. Sphericity and angularity are identified as the most important macroscale factors, while roughness has a weaker microscale influence.
ADVANCED POWDER TECHNOLOGY
(2024)
