449 Int. J. Mech. Eng. Rob. Res. 2013 Girja Lodhi, 2013 OPERATION AND MAINTENANCE OF CRUSHER HOUSE FOR COAL HANDLING IN THERMAL POWER PLANT Girja Lodhi1* *Corresponding Author: Girja Lodhi, Many utility systems in the world have power plants operating with fossil fuel.
· To understand the effects of thermal shock on microcrack propagation and permeability in coal, thermal shock tests were conducted on coal specimens by using a constant temperature drying oven (105 °C) and a SLX program controlled cryogenic tank. The growth and propagation of microcracks were measured with computer tomography (CT) scanning and scanning electron microscope (SEM) .
permeability was calculated using the modiﬁed Darcy's law for a compressible Permeability was measured either by the steadystate method or the pressure transient one. For the purpose to study the impact of coal deformation on the evolution of coal permeability, the data by using other methods57 are not included.
· Coal measures in China are rich in unconventional energy resources, with the amount of coalbed methane (CBM), shale gas, and tight sandstone gas being as high as 60–70 × 10 12 m 3 (Cao et al., 2014).Among these resources, tight sandstone gas, which forms in coal measure strata, features close sources and reservoirs as well as shortdistance migration and accumulation, while also .
Coal bed permeability is varying from millidarcy at 443 meter to millidarcy at 541 meter because of increasing number of fractures and drilling induced fracture found at the depth range of meter with maximum azimuth stress within the range of 22 34°N. Key ...
Abstract This paper presents experimental investigations on CO 2 /CH 4 binary gas flow in bulk coal under controllable stress conditions, focusing on sorptioninduced swelling/shrinkage and gas permeability associated with CO 2 sequestration enhanced coalbed methane (CO 2 ECBM) recovery. The gas flush tests with carbon dioxide were conducted on a specially designed true triaxial stress coal ...
The permeability of coal in relation to gases is a key parameter used to describe coal in the processes of fracturing CBM reservoirs in bituminous coal mines [25,26,27]. Laboratory measurements have shown that coal permeability decreases in an exponential manner as the effective stress increases [23,28,29,30,31,32,33].
These and other laboratory studies have shown that coal permeability decreases by one to two orders of magnitude when permeability decreases by one to two orders of magnitude when effective stress is increased by 2,000 psi [ MPa]. 9–11 Furthermore, stresssensitive permeability and porosity have been observed in experimental studies on various reservoirs.
The permeability of coal seams directly determines the disaster prevention effect of water injection. It is of great significance to realize the accurate fractal expression of coal structure and construct a fractal permeability model for elucidating the dynamic evolution law of the permeability of coal .
on coalseam permeability with constraints from the measurement of adsorption isotherm and associated volumetric strain, based on which a stressdependent permeability model is derived (Cui and Bustin 2005). Liu and Rutqvist (2010) developed a coalpermeability model for uniaxial strain and constant conﬁningstress
The soil permeability is a measure indiing the capacity of the soil or rock to allow fluids to pass through it. It is often represented by the permeability coefficient (k) through the Darcy's equation: V=ki. Where v is the apparent fluid velocity through the medium i is the hydraulic gradient, and K is the coefficient of permeability ...
Permeability shows a moderate decrease with increasing effective stress for He, CH 4 and CO 2. At constant effective stress, permeability decreases when the saturating gas changes from He to CH 4 and CO 2. Hysteresis of permeability with increasing and decreasing effective stress is not observed in crushed samples. The coal swells when CH
· Highpressure abrasive water jet flushing (HPAWJF) is an effective method used to improve coal seam permeability. In this study, based on the theories of gas flow and coal deformation, a coupled gasrock model is established to investigate realistic failure processes by introducing equations for the evolution of mesoscopic element damage along with coal mass deformation.
The permeability model can also be used as a tool to determine input parameters for field simulations by curvefitting laboratorygenerated permeability data. The new model is compared to two other widely used coal permeability models using a hypothetical coal with average properties. Introduction
permeability which, for simplicity, will be referred to as the permeability. A compliion with coal permeability is that it can vary significantly during gas production in response to decreases in pore pressure and gas desorptioninduced coal matrix shrinkage (Gray, 1987 ). Therefore a challenge for accurate reservoir
A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N 2 injection: experimental observations and numerical simulation. Bo Li acd, Junxiang Zhang * abcd, Zhiben Ding a, Bo Wang a and Peng Li b a Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization, Henan Polytechnic University, Jiaozuo, Henan 454003, China.
We performed experiments of cubic coal samples to investigate the permeability evolution and mechanical behaviour of coal under true triaxial stress conditions by using newly developed true triaxial geophysical apparatus. We analysed the effect of principal stresses on deformation and permeability characteristics of coal containing bedding planes.
· The results show that the fracture surface crushing, rearrangement, and compressional deformation of pulverized coal in the loading process lead to a drastic drop in permeability. Besides this, the axial permeability sensitivity to the confining stress is .