Experimental Study on Mine-Loess and Fly Ash Backfilling Material

2014 ◽  
Vol 1010-1012 ◽  
pp. 1518-1522 ◽  
Author(s):  
Kai Hua Sun
Keyword(s):  
Fly Ash ◽  
Coal Mine ◽  
Orthogonal Experiment ◽  
Weight Ratio ◽  
Solid Material ◽  
Mining Area ◽  
Filling Material ◽  
Optimal Range ◽  
North West ◽  
Four Levels

In order to reduce the cost of backfilling materials in north-west mining area, the feasibility of making the loess as backfilling material in coal mine was discussed in this paper, an orthogonal experiment were conducted and the ratio of backfilling material is gained by author. The experiment was based on the material as main material: loess with fly ash, auxiliary material:cement with lime and other additive agent. According to the mechanism of alkali excitation on the potential activity of the fly ash , a four levels and five factors experiment was conducted by using the orthogonal principle, to analyze the influence of various factors on the main indicators of material specimen, the new material ratio that meet the requirements of backfilling is obtained. Experimental results indicate that: it's feasible to make the loess with fly ash as filling material in coal mine, the appropriate slurry concentration is 60% ~ 65% and the optimal range of the weight ratio of loess with fly ash is 1:1.5~1:3, the optimal range of the weight ratio of auxiliary materials with solid material is 30%~33% and 5%～7% of additive dosage respectively, the appropriate curing time is 28 days.

Study on Basic Experiment of Coal Waste Paste Filling Material

2012 ◽  
Vol 174-177 ◽  
pp. 384-389 ◽  
Author(s):  
Xin Guo Zhang ◽  
Ning Jiang ◽  
Heng Wang ◽  
Yang Yang Li
Keyword(s):  
Fly Ash ◽  
Coal Mine ◽  
Coal Waste ◽  
Hydration Reaction ◽  
Filling Material ◽  
Hydration Products ◽  
Xrd Diffraction ◽  
Speed Up ◽  
Diffraction Patterns ◽  
Cementing Material

Based on present situation that coal mining under buildings, water bodies and railways, and solid wastes mainly including coal waste, fly ash in coal mine of our country, optimization proportioning of paste filling material and hydration reaction mechanism is systematicaly researched combining with project practice of paste filling in Daizhuang Coal Mine, Zibo Mining Group. The result shows that: Proportioning design P10 can be used as the optimal proportion results, the rate of cementing material is that the proportion: fly ash: coal waste is 1:4:6, quantity concentration is 74%; Coal waste paste XRD diffraction patterns of different instar shows that its hydration products at different instar stage are mainly gelation of CH, Aft and C-S-H; Relative content of each material in hydration products is different at different instar stage; With scanning electron microscope a certin ettringite is producted after coal waste paste hydrated 8h, and content of C-S-H gelation and CH gelation is increased gradually; Hydration process of portland cement is speed up and the strength of paste is enhanced.

scholarly journals Study on Filling Material Ratio and Filling Effect: Taking Coarse Fly Ash and Coal Gangue as the Main Filling Component

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Changxiang Wang ◽  
Yin Liu ◽  
Hao Hu ◽  
Yangyang Li ◽  
Yao Lu
Keyword(s):  
Fly Ash ◽  
Material Selection ◽  
Orthogonal Experiment ◽  
Coal Gangue ◽  
Environmental Benefits ◽  
Filling Material ◽  
Range Analysis ◽  
Filling Materials ◽  
Filling Simulation ◽  
Main Component

Filling mining is an effective way to settle the dilemma of “Three Down and One Above” in coal mining. Fly ash and coal gangue can be used as filling materials with significant social, economic, and environmental benefits. Using coarse fly ash base as cementing material and coal gangue as aggregate, orthogonal experiment of filling paste was conducted in this study. The range analysis was performed for the strength and transportation requirements of filling paste, and the optimum proportion was determined by the comprehensive balance method. In order to verify the filling effect, a dynamic filling simulation device was designed, and a comparative simulation test of caving mining and dynamic filling mining was carried out. Results show that the filling paste with fly ash and coal gangue as the main component can meet the requirements of filling design and application. This research provides a reference for the material selection and proportion design of paste filling.

scholarly journals Mechanism by Which Backfill Body Reduces Amount of Energy Released in Deep Coal Mining

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Wenyue Qi ◽  
Jixiong Zhang ◽  
Nan Zhou ◽  
Zhongya Wu ◽  
Jun Zhang
Keyword(s):  
Energy Density ◽  
Coal Mining ◽  
Coal Mine ◽  
Strain Energy Density ◽  
Strain Energy ◽  
Mining Area ◽  
Filling Material ◽  
Ultrahigh Energy ◽  
Energy Density Distribution ◽  
Working Face

Deep coal mining is unavoidable, and the complex mining environments and the increasing dangers associated with ultrahigh energy accumulation and release from mining disturbances renders it extremely difficult to maintain a safe and stable stope. Solid backfilling technology directly uses coal gangue and other solid wastes in the mining area to fill the gob after mining. Support from the backfill body can inhibit the movement of overlying rock strata and significantly alleviate the influence of mining. In this study, the correlations between the deformation of gangue filling material and the characteristics of energy dissipation were examined under lateral uniaxial compression. The strain energy density distributions of backfilling and caving mining methods were simulated using numerical modeling. The results showed that the strain energy density distribution of backfilling mining was less concentrated, and its peak value was lower than that of caving mining by 51.0%, indicating that backfilling could effectively reduce the amount of energy released from mining rocks. The dense backfill mining area of the No. 9301 face in Tangkou Coal Mine was used as a case study. Measures for controlling the backfill body compaction for reducing the amount of energy released from mining rocks were proposed. These measures include optimizing the support structure and filling material formula, controlling the preroof subsidence, and ensuring an appropriate number of tamping strokes. The monitoring results of the backfilling quality, surface subsidence, and microseismic energy of No. 9301 working face in Tangkou Coal Mine showed that when the backfill body filling ratio control value was 82.28%, the total number of microseisms and the amount of energy released from the mining working face were significantly lower compared to those of the caving method. This study demonstrated that the backfill body could effectively reduce the amount of energy released from mining rocks, thereby realizing management of mine earthquake and sustainable deep coal mining.

Freezing Pressure and its Influencing Factors of Deep Clay Layer in the Huainan Mining Area

2012 ◽  
Vol 170-173 ◽  
pp. 836-841
Author(s):  
Wei Shao ◽  
Bin Lin
Keyword(s):  
Coal Mine ◽  
Good Description ◽  
Mining Area ◽  
Frost Heave ◽  
Dynamic Monitoring ◽  
Clay Layer ◽  
Formation Pressure ◽  
Closed Systems ◽  
Permanent Formation ◽  
Layer Deformation

Gu Bei coal mine deep shaft freezing pressure of calcareous clay dynamic monitoring showed that the freezing pressure of the calcareous clay fastest grow in the first 2 weeks after the sidewall concrete pouring , freezing pressure has obvious direction . Analysis showed that the layer of freezing pressure is mainly calcareous clay layer deformation pressure, size and the temperature of well has a positive correlation. Maximum freezing pressure of the deep calcareous clay layer approximate the permanent formation pressure values and the maximum frost heave force determined by the frost heave experiments in indoor closed systems ,the average freezing pressure with depth variation of the exponential function can be used to good description.

TRACE ELEMENT ANALYSIS OF FLY ASH BY PIXE

1999 ◽  
Vol 09 (03n04) ◽  
pp. 417-422 ◽  
Author(s):  
V. VIJAYAN ◽  
S. N. BEHERA
Keyword(s):  
Fly Ash ◽  
Trace Element ◽  
Power Plants ◽  
Building Materials ◽  
Thermal Power ◽  
Trace Element Analysis ◽  
Chemical Properties ◽  
Solid Material ◽  
Thermal Power Plants ◽  
Element Analysis

Fly ash is a major component of solid material generated by the coal-fired thermal power plants. In India the total amount of fly ash produced per annum is around 100 million tonnes. Fly ash has a great potential for utilization in making industrial products such as cement, bricks as well as building materials, besides being used as a soil conditioner and a provider of micro nutrients in agriculture. However, given the large amount of fly ash that accumulate at thermal power plants, their possible reuse and dispersion and mobilization into the environment of the various elements depend on climate, soils, indigenous vegetation and agriculture practices. Fly ash use in agriculture improved various physico-chemical properties of soil, particularly the water holding capacity, porosity and available plant nutrients. However it is generally apprehended that the application of large quantity of fly ash in fields may affect the plant growth and soil texture. Hence there is a need to characterize trace elements of fly ash. The results of trace element analysis of fly ash and pond ash samples collected from major thermal power plants of India by Particle Induced X-ray Emission (PIXE) have been discussed.

The Characteristics of Collapse Columns in Duanwang Minefield and their Influences on Gas Emission Quantities of Coal Faces

2013 ◽  
Vol 634-638 ◽  
pp. 3537-3540
Author(s):  
Xin Xian Zhai ◽  
Xiao Ju Li ◽  
Yan Wei Zhai
Keyword(s):  
Coal Mine ◽  
Production Capacity ◽  
Mining Area ◽  
Mine Safety ◽  
Shanxi Province ◽  
Free Form ◽  
Karst Collapse ◽  
Coal Face ◽  
Gas Emission ◽  
Mining Depth

Duanwang Coal Mine is located at north of Qinshui coalfield in Shanxi province, China, which gently inclined and thick seams have been mined. Authorized production capacity of the coal mine is 1.8Mt/a. With the increase of mining depth, the mine gas emission quantity increased. Karst collapse columns are very developed in the minefield, and the phenomenon of abnormal gas emission always occurred at the coal face and driving gateway around the collapse columns, then the mine became high gassy one from low gassy mine. Using field measurement and theoretical analysis methods, the following conclusion can be drawn. Karst collapse columns have significant influences on gas emission of the coal face and driving gateway. Here are large amount of free form gas into and around the collapse columns, the collapse columns were disclosure while driving gateway, a large amount of the free gas into collapse column would be instantly released, which caused abnormal gas emission at driving gateway, even leading to gas density exceeding limitation by Coal Mine Safety Regulation of China. However, during mining area of the collapse columns, gas emission quantity at coal face was relatively smaller.

scholarly journals Water level collapse effect of deep well in mining area

2021 ◽  
Vol 233 ◽  
pp. 03037
Author(s):  
LIN Mei ◽  
DONG Xiaona
Keyword(s):  
Water Level ◽  
Coal Mine ◽  
Earth Tide ◽  
Mining Area ◽  
Observation Data ◽  
Aquifer System ◽  
Deep Well ◽  
Original Curve ◽  
Level Data ◽  
Water Level Data

The use of Zaozhuang of Shandong province coal mine area is tao chong lu 15 Well and meteorological observation data, the three elements of observation Wells with tao chong effect comparing the dynamic characteristics of the mines. It is difficult to determine whether the stress state of the aquifer system in which the well was observed before the collapse has changed because of the water level in the deep well of Lu15 well on the original curve. Nakai fitting model is adopted to calculate the earth tide response amplitude factor ratio based on the water level data of Lu15 well, and the possibility of collapse caused by stress change is discussed in combination with non-natural seismic events in Taozhuang Coal mine

Sign in / Sign up

Export Citation Format

Share Document