Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan p...Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan particles （FCCP）, was examined. The effects ofpH, stirring time, sedimentation time and temperature on color, COD, turbidity and NH3-N removal were determined. The optimum dosage of FCCP and the influence of individual factors on removal efficiency were tested. The optimum parameters determined using the L16 （45） orthogonal experiment were as follows： FCCP （weight ratio of chitosan to fly-ash 1：6） dosage, 4 g.L^-1; temperature, 35℃; pH, 4. The stirring time and sedimentation time were 20 min and 5 h, respectively. Under these optimum conditions, the color, COD and NH3-N removal ratios were 97%, 80% and 75%, respectively.展开更多
The theory and method of wavelet packet decomposition and its energy spectrum dealing with the coal rock Interface Identification are presented in the paper. The characteristic frequency band of the coal rock signal c...The theory and method of wavelet packet decomposition and its energy spectrum dealing with the coal rock Interface Identification are presented in the paper. The characteristic frequency band of the coal rock signal could be identified by wavelet packet decomposition and its energy spectrum conveniently, at the same time, quantification analysis were performed. The result demonstrates that this method is more advantageous and of practical value than traditional Fourier analysis method.展开更多
The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mecha...The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.展开更多
Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained fr...Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).展开更多
基金Supported by the Science and Technology Development Foundation of Foshan (No.2005060071)
文摘Printing and dyeing industry is a considerable source of environmental contamination. In this study treatment of printing and dyeing wastewater with a new type of sewage treatment agent, fly-ash coated with chitosan particles （FCCP）, was examined. The effects ofpH, stirring time, sedimentation time and temperature on color, COD, turbidity and NH3-N removal were determined. The optimum dosage of FCCP and the influence of individual factors on removal efficiency were tested. The optimum parameters determined using the L16 （45） orthogonal experiment were as follows： FCCP （weight ratio of chitosan to fly-ash 1：6） dosage, 4 g.L^-1; temperature, 35℃; pH, 4. The stirring time and sedimentation time were 20 min and 5 h, respectively. Under these optimum conditions, the color, COD and NH3-N removal ratios were 97%, 80% and 75%, respectively.
文摘The theory and method of wavelet packet decomposition and its energy spectrum dealing with the coal rock Interface Identification are presented in the paper. The characteristic frequency band of the coal rock signal could be identified by wavelet packet decomposition and its energy spectrum conveniently, at the same time, quantification analysis were performed. The result demonstrates that this method is more advantageous and of practical value than traditional Fourier analysis method.
基金Supported by the National Science Foundation of China (50874042, 50674046)National Science Important Foundation (50634050)Hunan Science Foundation (06JJ50092)
文摘The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.
基金supported by the National Natural Science Foundation of China (No. 40972207)the National Science and Technology Major Projects (No. 2011ZX05034-005)the PAPD of Jiangsu Higher Education Institutions
文摘Coalbed methane(CBM) commercial development requires choosing the arrangement of the wells.This should be done by considering the corresponding input-output(investment-profit) efficiencies.Simulations were obtained from the computer modeling group(CMG) given the reservoir conditions of the Panzhuang block in the southern part of the Qinshui Basin.This is a demonstration region for CBM development located in Shanxi province of northern China.The sensitivity of gas production from a single vertical well to the primary reservoir parameters was estimated first.Then multi-well gas production from three different well patterns was simulated to estimate the most appropriate well spacing.Combining the investment requirements then gave investment-profit efficiencies for these well patterns.A data envelopment analysis(DEA) model was used to optimize the efficiency.The results show that the permeability,the reservoir pressure,and the gas content have an evident impact on single well gas production.The desorption time has little or no affect on production.The equilateral triangular well pattern(ETWP) in a 400 m well spacing is,for multi-well development,the optimal pattern.It has a better input-output ratio,a longer stable yield time,and provides for greater CBM recovery than does either the rectangular well pattern(RWP) or the five point well pattern(FPWP).
