Prediction of the Adaptability of Using Continuous Extraction and Continuous Backfill Mining Method to Sequestrate CO2-A Case Study

Abstract

The consumption of coal resources has caused an increase in CO2 emissions. A scientific concept that can realize CO2 sequestration, the harmless treatment of solid wastes, and coal extraction under buildings, railways, and water bodies (BRW) is proposed. First, a novel CO2 mineralized filling body (CMFB) is developed by employing CO2 gas, fly ash, silicate additives, and cement. It is then injected into the mined-out mining roadways (MRs) of the continuous extracting and continuous backfill (CECB) mining method to ameliorate the overburden migration and thus extract the coal body under the BRW. The AHP-fuzzy comprehensive evaluation method was employed to construct a prediction model for the suitability of this concept. Subsequently, the evaluation model is generalized and applied to the Yu-Shen mining area. Each indicator affecting adaptability is plotted on a thematic map, and the corresponding membership degree is determined. The aptness for 400 boreholes distributed in the entire area was determined and a zoning map which divides the whole area into good, moderate, slightly poor, and extremely poor suitability was drawn. This paper puts forward a mathematical model for predicting the suitability of using CECB and CMFB to sequestrate CO2. Research results can provide references for determining the site of CO2 sequestration under the premise of maximizing the economic and ecological benefits, which is conducive to constructing ecological, green, and sustainable coal mines.

Study of the mining and aquifer interactions in complex geological conditions and its management

“…Finally, it was judged whether the size of the water prevention coal (rock) pillar of the working face was in line with the safe mining range, and the feasibility of safe mining under the aquifer of the bedrock working face was comprehensively analyzed. The research conclusion provides important safety guidance significance for the mining of similar mines 25 , 26 .…”

Prediction of Water-Blocking Capability of Water-Seepage-Resistance Strata Based on AHP-Fuzzy Comprehensive Evaluation Method—A Case Study

“…In addition, there are also some scholars who employed AHPF to evaluate the WBC of an aquiclude in a mining area, but all of them take an average value to represent the whole mining area to determine the membership degree of the influencing factors [71][72][73]. Their prediction results are obviously unreasonable, inaccurate and irrational, because the hydrogeological conditions at different locations in the same mining area are obviously varied [74]. Furthermore, different from the traditional evaluation of the WBC of an aquifuge, from the perspective of the mining-induced permeability deterioration rate of the overburden, the concept of "three seepage zones" is firstly put forward in this paper, and the scientific connotations of the nominal WSRZ (after coal extraction), which is important for WPCM, are systematically defined.…”

Numerical Study on Deposition Behavior of Micron-Sized Suspended Solids in Broken Rock Mass within a Goaf Based on Coupled CFD-DEM Method

“…After coal mining, the collapse of the top rock layer in the goaf leads to the settlement of the upper strata. The stratigraphic stress is disturbed and redistributed, showing different stress distribution characteristics in different areas of the goaf [53][54][55]. This stress distribution affects the degree of compaction of the broken rock mass, which in turn affects the broken coal rock's particle size distribution and pore size.…”