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Articles 2851 - 2880 of 5623

Full-Text Articles in Oil, Gas, and Energy

Research And Application Of Cbm Surface Extraction Based On Coal Mine With “Gas Drainage First, Construction Later” And Resource Development, Wang Jing, Yao Tuanqi, Cheng Bin Aug 2019

Research And Application Of Cbm Surface Extraction Based On Coal Mine With “Gas Drainage First, Construction Later” And Resource Development, Wang Jing, Yao Tuanqi, Cheng Bin

Coal Geology & Exploration

Aiming at the safety index put forward by "gas drainage first, construction later" of coal mine at present and the resource characteristics of many coal seams in northern Guizhou Province, and at the same time making up for the lack of systematization and large blind area of surface gas drainage deployment at present, this paper took Duijiangnan coal mine as an example to carry out the research of coal bed methane surface drainage deployment. Based on the complex topographic conditions, coal seam development characteristic(multiple layers, thin thickness, group distribution), coal body structure, development and deployment requirements in this area, the …


Influencing Factors Of Surface Gas Extraction Effect In Wangpo Minefield Of Jincheng Mining Area, Du Zhiqiang Aug 2019

Influencing Factors Of Surface Gas Extraction Effect In Wangpo Minefield Of Jincheng Mining Area, Du Zhiqiang

Coal Geology & Exploration

The effect of surface gas extraction in Wangpo minefield of Jincheng mining area is poor. In order to find out the causes and to guide the construction of future surface gas extraction, the occurrence conditions of CBM resources in the study area were analyzed and compared with those of adjacent Chengzhuang minefield where the extraction effect is good, the quality of the produced water was tested, at the same time the fracture forms were observed underground. The comprehensive analysis indicated that the abundance of coal gas resources and the reservoir conditions were the major intrinsic basic factors influencing the gas …


Coal Control Factors Of Middle Jurassic Shimengou Formation In Beidatan Area, East Part Of The Northern Qaidam Basin, Peng Minghong, Tian Jingchun, Zhang Xiang, Chen Lei, Zeng Jianqiang, Wang Suying Aug 2019

Coal Control Factors Of Middle Jurassic Shimengou Formation In Beidatan Area, East Part Of The Northern Qaidam Basin, Peng Minghong, Tian Jingchun, Zhang Xiang, Chen Lei, Zeng Jianqiang, Wang Suying

Coal Geology & Exploration

The key of the coal exploration in Beidatan area of Qinghai Province is the coal accumulation environment in the sedimentary period and the control of coal seam occurrence by tectonic action before and after sedimentation. To identify Shimengou Formation coal controlling factors in Beidatan area, east part of the northern Qaidam basin, effectively guide the coal exploration of the coal bearing area, through field outcrops, drilling, geophysical prospecting and other geological information system, based on the analysis of coal accumulating environment and structural function of Shimengou Formation in Beidatan area, the control factors of coal were deeply discussed from coal …


Table Of Contents, The Editors Aug 2019

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Technology And Application Of Indirect Fracturing In Cbm Vertical Well Of Broken And Soft Coal Seam With Low Permeability, Zhou Jiajia Aug 2019

Technology And Application Of Indirect Fracturing In Cbm Vertical Well Of Broken And Soft Coal Seam With Low Permeability, Zhou Jiajia

Coal Geology & Exploration

In order to solve the problems of pulverized coal output and fracturing fracture not easy to extend during fracturing operation in the broken and soft coal seam with low permeability, the adaptability and fracturing fracture distribution of CBM during indirect fracturing are studied by means of in-situ stress and numerical simulation, and the engineering practice of indirect fracturing has been tested in Hongshandian mining area of Hunan Province. The results show that indirect fracturing can effectively improve the fracturing effect of the broken and soft coal seam with low permeability, and increase the fracture length. When the roof and floor …


Coalbed Methane Migration Mechanism Under Adsorption-Desorption Condition In Coal, Liu Yongqian, Zhang Shulin, Shu Longyong Aug 2019

Coalbed Methane Migration Mechanism Under Adsorption-Desorption Condition In Coal, Liu Yongqian, Zhang Shulin, Shu Longyong

Coal Geology & Exploration

The migration law of coalbed methane(CBM) with adsorption has always been the focus of attention in the field of coalbed methane geology. In order to study the mechanism of CBM migration under adsorption-desorption state, the deduction of gas adsorption-desorption equation and theoretical analysis of gas diffusion-seepage in porous media were carried out, and new viewpoints were put forward by means of experimental analysis of CBM migration. The results identified that:(1) for the CBM migration, pore structure of coal body has the storage-resistance effect, the dual functions of gas storage and gas pressure drop form the basic feature of coal matrix, …


Occurrence Of Antimony In Magmatic Intrusive Coal Seam: A Case Study From The Wolonghu Coal Mine, Huaibei Coalfield, China, Ou Jinping, Zheng Liugen, Wei Xiangping, Liu Sikui, Li Liyuan, Liu Meng, Huang Xiaoyu Aug 2019

Occurrence Of Antimony In Magmatic Intrusive Coal Seam: A Case Study From The Wolonghu Coal Mine, Huaibei Coalfield, China, Ou Jinping, Zheng Liugen, Wei Xiangping, Liu Sikui, Li Liyuan, Liu Meng, Huang Xiaoyu

Coal Geology & Exploration

In order to investigate the influence of magmatic alteration on the occurrence characteristics of antimony in coal seam, 12 samples of magmatic magma and coal were collected from Wolonghu coal mine in Huaibei coalfield, Anhui Province, and the content of Sb was determined by atomic fluorescence spectrometry(AFS). The coal quality parameters are analyzed. The results are as follows:the coal in Wolonghu magmatic intrusion area has the characteristics of ultra-low volatile matter, medium ash content and ultra-low sulfur content. And the main forms of sulfur in coal are organic sulfur and pyrite sulfur. Under the influence of magmatic hydrothermal solution, ash …


Analysis Of Reservoir Conditions Of Shale Gas In Middle Permian Wenbishan Formation In Fujian Province, Chen Quanlin Aug 2019

Analysis Of Reservoir Conditions Of Shale Gas In Middle Permian Wenbishan Formation In Fujian Province, Chen Quanlin

Coal Geology & Exploration

This study is performed on the geological conditions of shale gas in Middle Permian Wenbishan Formation in Fujian Province. It is based on organic geochemistry, rock minerals and reservoir physical property after geology survey and drilling. The results indicate that kerogen is Ⅲ-type, organic carbon is usually between 1% to 2%, Rran is between 3.76% to 4.91% in the shale of Wenbishan Formation, and the shale is in the mature stage. The content of brittle minerals is generally low. The shale has medium porosity and extremely low permeability, the micro and meso-pores constitute the major space for gas adsorption. …


Water Inflow Law Of The First Working Face Based On Water Pre-Draining From Roof, Li Yongtao, Yang Jian Aug 2019

Water Inflow Law Of The First Working Face Based On Water Pre-Draining From Roof, Li Yongtao, Yang Jian

Coal Geology & Exploration

In order to establish water control technology system in Inner Mongolia-Shaanxi contiguous area, we carried out some researches(e.g. overburden failure law, hydrogeological conditions, prediction of water inflow and pre-drainage of roof water) in Nalinhe No.2 coal mine. The results showed that three methods(i.e. coring, drilling fluid leakage observation and borehole color TV detection) were used to explore water-conducting fracture zone(103.23 m), and the ratio of the height of the fractured zone to the mining height was 18.8. Water-conducting fracture zone could connect three aquifers, and the Zhiluo Formation bottom aquifer was the main aquifer threatening safety mining. Water inflow and …


Microseismic Test And Numerical Simulation Analysis Of Floor Failure Depth Of Isolated Coal Mining Face, Zhao Chunhu Aug 2019

Microseismic Test And Numerical Simulation Analysis Of Floor Failure Depth Of Isolated Coal Mining Face, Zhao Chunhu

Coal Geology & Exploration

Aiming at the damage of coal seam floor caused by mining in isolated coal mining face, taking 11913 isolated coal mining face in Gequan coal mine of Hebei Province as the research object, and using KJ959 coal mine microseismic monitoring system to detect the floor failure depth. It is recognized that the microseismic events mainly occur in the roadway of the isolated coal mining face during the mining process, and the maximum vertical failure depth is about 20~25m; Moreover, using the COMSOL multi-physical field numerical simulation platform, the variation of in-situ stress and failure law of coal seam floor under …


Modification Function Of Magnetic Treatment On Grouting Clay Slurry, Xue Weifeng, Wang Sujian, Deng Zengshe, Huang Kejun, Han Lei, Ji Ruijun, Liang Shaojian Aug 2019

Modification Function Of Magnetic Treatment On Grouting Clay Slurry, Xue Weifeng, Wang Sujian, Deng Zengshe, Huang Kejun, Han Lei, Ji Ruijun, Liang Shaojian

Coal Geology & Exploration

Clay slurry was treated through magnetization. The characteristics of the physical property change of the clay slurry after magnetic treatment such as viscosity, density, pH value, conductivity, syneresis rate, concretion rate and anti-permeability were studied. After magnetic treatment, density, viscosity and syneresis rate of the clay slurry decrease, pH, conductivity and concretion rate increase, the syneresis rate and the concretion rate are improved with the magnetization time. The magnetic treatment improves the rheological property of clay slurry, the anti-permeability performance of the cemented body of clay slurry after magnetic treatment rises greatly compared to the cemented body of clay slurry …


Inversion Analysis Of Earth Pressure For Limited Soil Between Oblique Support Retaining Foundation Pit And Adjacent Basement, Zhang Guomao, Peng Wenxiang Aug 2019

Inversion Analysis Of Earth Pressure For Limited Soil Between Oblique Support Retaining Foundation Pit And Adjacent Basement, Zhang Guomao, Peng Wenxiang

Coal Geology & Exploration

In order to study the distribution of earth pressure for limited soil between oblique support retaining foundation pit and adjacent basement, back analysis of site monitoring data of a foundation pit was studied. Based on the improved cubic spline method of the trial algorithm, Matlab software was used to calculate the bending moment value of the supporting structure and the earth pressure value behind the pile. The results show the earth pressure of limited soil is influenced by displacement mode, non-limit state and boundary conditions. The active earth pressure of limited soil above the excavation surface shows a distinct "R" …


Numerical Simulation On Mechanism Of Thrust Fault Reactivation During Mining, Min Feihu, Xiang Biwei, Liu Hui, Zhu Xiaojun Aug 2019

Numerical Simulation On Mechanism Of Thrust Fault Reactivation During Mining, Min Feihu, Xiang Biwei, Liu Hui, Zhu Xiaojun

Coal Geology & Exploration

It is a hot issue in mine disaster research about the activation of faults during the process of coal mining and excavation. In order to reveal the influence of coal mining on fault activation under different fault dip conditions, Xinji No.2 mine in Huainan coalfield was taken as an example, and numerical simulation with FLAC3D was used to systematically study the dynamic activation law of thrust faults during mining beside the faults, and to clarify the relationship among fault activation position and fault dip angle and excavated distance of working face. The results show that the fault activation is …


Application Of Seismic Exploration Technology In Forecasting Unconventional Gas Enrichment Area Of Coal Measures, Wang Shuwei Aug 2019

Application Of Seismic Exploration Technology In Forecasting Unconventional Gas Enrichment Area Of Coal Measures, Wang Shuwei

Coal Geology & Exploration

For forecasting unconventional gas enrichment area in coal measures of eastern Ordos basin, seismic exploration was used to forecast the gas in this new field. First of all, it took the post-stack impedance inversion to forecast the lithology of the reservoir, it can get the number of sample points from the impedance threshold, and get the thickness of time by cal-culating the sampling rate, after that it can get the strata thickness by multiplying the thickness of time and the velocities of strata; second, it took the pre-stack AVO inversion to forecast the lithology gas-bearing properties of the reservoir, based …


Constrained Inversion Method And Application Effect Of Tem Data Of Fixed Source Loop Device, Hou Yanwei, Yao Weihua Aug 2019

Constrained Inversion Method And Application Effect Of Tem Data Of Fixed Source Loop Device, Hou Yanwei, Yao Weihua

Coal Geology & Exploration

In order to eliminate the obvious framing effect after the TEM fixed source loop device increases the receiving area, to improve the delamination ability of TEM to enhance the fine resolution for different electrical strata, the regularization inversion method with constraint is adopted. In the inversion algorithm, the Lagrange factor is adjusted adaptively by CMD regularization factor. In order to ensure the efficiency, stability and convergence of the results of the inversion process, the thickness of each layer of the inversion model is discretized according to the equal logarithmic interval, and the ill conditioned property of the matrix equation is …


Experimental Study And Economic Evaluation Of Low Temperature Drying Treatment Of Abandoned Water-Based Drilling Fluid, Li Zhijun, Liu Xusan, Wang Bo, Zhao Wei Aug 2019

Experimental Study And Economic Evaluation Of Low Temperature Drying Treatment Of Abandoned Water-Based Drilling Fluid, Li Zhijun, Liu Xusan, Wang Bo, Zhao Wei

Coal Geology & Exploration

Abandoned water-based drilling fluids are the waste of oil drilling engineering operations. It will not only keep the cost of drilling fluid high, but also have a very adverse impact on the environment if it is directly discharged. Reusing of abandoned water-based drilling fluid after low-temperature drying treatment is one of treatment methods which is economic and conforms to the modern development trend. In this paper, the experimental study and economic evaluation of the low-temperature drying technology of polymer drilling fluid system, sulfonated drilling fluid system and Sichuan shale gas well drilling fluid system were conducted. The results show that …


Instability Mechanism And Anti-Sloughing Drilling Fluid Technique For Deep Coal Seam Of Tarim Basin, Li Heng, He Shiming, Tang Ming, Li Ning, Yang Pei, Zhang Zhen Aug 2019

Instability Mechanism And Anti-Sloughing Drilling Fluid Technique For Deep Coal Seam Of Tarim Basin, Li Heng, He Shiming, Tang Ming, Li Ning, Yang Pei, Zhang Zhen

Coal Geology & Exploration

In view of the complicated problems of drilling fluid leakage and hole collapse during the drilling of deep coalbed in Tarim basin, the microstructure and physical and chemical properties of coal were tested by vitrinite reflectance analysis, X ray diffraction and scanning electron microscope, and the mechanism of coal seam instability was confirmed. The fixed carbon content of the coal exceeds 60%, the vitrinite reflectance is greater than 1.1%, and coal have high degree of coalification, is brittle and easy to break. The total amount of clay mineral is less than 25%, and there is no strong water-sensitive mineral montmorillonite …


Study On Slope Stability And The Effect Of Highfill On The Mechanical Properties Of Red Clay Foundation, Gao Shengxiang, Xu Qiang, Ma Hongyu, Wu Shenglin, Wu Kang, Liu Peng, Wu Zehui Aug 2019

Study On Slope Stability And The Effect Of Highfill On The Mechanical Properties Of Red Clay Foundation, Gao Shengxiang, Xu Qiang, Ma Hongyu, Wu Shenglin, Wu Kang, Liu Peng, Wu Zehui

Coal Geology & Exploration

This paper takes a highfill slope in Anning in Yunnan Province as a case, using investigation, monitoring and other methods, on the basis of the distribution characteristics of red clay, the physical and mechanical properties of red clay before and after filling were analyzed, then the stability of slope was studied by numerical simulation software. The results show that the physical and mechanical indexes of the red clay foundation decrease first and then increase before and after the fill project, the stability of the fill slope shows the trend of decrease first and then increase. The ground fissures in the …


A Pipeline Robot Detection Image Enhancement Method Based On Image Fusion And Improved Threshold, Yuan Mingdao, Tan Cai, Li Yang, Xu Yunqian, Zhang Xuhui, Yang Jingxue Aug 2019

A Pipeline Robot Detection Image Enhancement Method Based On Image Fusion And Improved Threshold, Yuan Mingdao, Tan Cai, Li Yang, Xu Yunqian, Zhang Xuhui, Yang Jingxue

Coal Geology & Exploration

Pipeline robot detection technology can quickly, accurately and intuitively identify the structure and hidden functional troubles of pipeline. However, due to the restriction of the pipeline environment, the detected images have problems such as uneven illumination, low contrast and blurred details. Therefore, an enhancement technique for detected image of pipeline robot is proposed. First, the contrast limited adaptive histogram equalization(CLAHE) and homomorphic filtrate(HF) are applied to deal with the problem of uneven illumination and low contrast, and the result images of the two methods are fused. Secondly, the fusion images are transformed by the Nonsubsampled Contourlet Transform(NSCT), and the improved …


Detection Accuracy Analysis Of Tsp And Its Application In A River-Crossing Tunnel Construction, Li Junjie, Zhang Honggang, He Jianshe, Rong Xin, Li Jianqiang, Guo Jiahao Aug 2019

Detection Accuracy Analysis Of Tsp And Its Application In A River-Crossing Tunnel Construction, Li Junjie, Zhang Honggang, He Jianshe, Rong Xin, Li Jianqiang, Guo Jiahao

Coal Geology & Exploration

Aiming at the problems of TSP such as long detection time and strong experience-depending, in order to improve the accuracy and the efficiency of TSP detection, we analyzed the key factors which affect data acquisition and processing accuracy of TSP and summarized the experiences of improving the detection efficiency of TSP. In combination with the TSP advanced geological prediction work in a river-crossing tunnel for water distribution project in Qiandaohu lake, the TSP tracing prediction or GPR detection in the area where the TSP resolution decreases were carried out and the geophysical abnormal area was verified by drilling. The results …


Synergistic Development Of Shipping Center And Technological Innovation, Mingze Du Aug 2019

Synergistic Development Of Shipping Center And Technological Innovation, Mingze Du

World Maritime University Dissertations

No abstract provided.


The Impact Of Imo's Global Sulphur Cap The Shipping Industry And The Latter's Countermeasure, Jorge Morales Aug 2019

The Impact Of Imo's Global Sulphur Cap The Shipping Industry And The Latter's Countermeasure, Jorge Morales

World Maritime University Dissertations

No abstract provided.


Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian Aug 2019

Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian

LSU Master's Theses

During crude oil spill events, vegetation in marsh environments sequester polycyclic aromatic hydrocarbons (PAHs) from the crude oil by partitioning from the air phase through the waxy cuticle on the leaf surface. Recent studies from Macondo oil-impacted marshes have demonstrated that cycling of low molecular weight petrogenic PAHs occurs through the cuticle and other leaf tissue. At present, our understanding of how PAHs travel through the cuticle is coarse and limited by grab samples across the entire leaf, which preventing a full understanding the dynamics of PAH cycling in this environment. Multiphoton (MP) confocal microscopy visualizes the distribution of PAHs …


Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin Aug 2019

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge …


Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin Aug 2019

Metabolic Engineering Of Cyanobacteria For Production Of Chemicals, Po-Cheng Lin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Concerns over the impact of climate change caused by CO2 emission have driven the research and development of renewable energies. Microbial production of chemicals is being viewed as a feasible approach to reduce the use of fossil fuels and minimize the impact of climate change. With recent advances in synthetic biology, microorganisms can be engineered to synthesize petroleum-based chemicals and plant-derived compounds. Cyanobacteria are photosynthetic prokaryotes that use only sunlight, CO2, and trace minerals for growth. Compared to other microbial hosts, cyanobacteria are attractive platforms for sustainable bioproduction, because they can directly convert CO2 into products. However, the major challenge …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

Head and Heart Posters 2019

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

Learning with your Head & Heart

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

2019 Cohort

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Monitoring Tropospheric Gases With Small Unmanned Aerial Systems (Suas) During The Second Cloudmap Flight Campaign, Travis J. Schuyler, Sean C. C. Bailey, Marcelo I. Guzman Aug 2019

Monitoring Tropospheric Gases With Small Unmanned Aerial Systems (Suas) During The Second Cloudmap Flight Campaign, Travis J. Schuyler, Sean C. C. Bailey, Marcelo I. Guzman

Chemistry Faculty Publications

Small unmanned aerial systems (sUAS) are a promising technology for atmospheric monitoring of trace atmospheric gases. While sUAS can be navigated to provide information with higher spatiotemporal resolution than tethered balloons, they can also bridge the gap between the regions of the atmospheric boundary layer (ABL) sampled by ground stations and manned aircraft. Additionally, sUAS can be effectively employed in the petroleum industry, e.g., to constrain leaking regions of hydrocarbons from long gasoducts. Herein, sUAS are demonstrated to be a valuable technology for studying the concentration of important trace tropospheric gases in the ABL. The successful detection and quantification of …


Federal Jurisdiction For Above-Ground Oil Storage Tanks: A Practical Analysis For Navigating Federal Regulations, Kathryn Hussong Aug 2019

Federal Jurisdiction For Above-Ground Oil Storage Tanks: A Practical Analysis For Navigating Federal Regulations, Kathryn Hussong

St. Mary's Law Journal

Clear, consistent, and concise jurisdictional boundaries will aid pipeline operators to determine which regulations apply to their operations and associated facilities. This will help alleviate legal and financial risk to pipeline operators, who may be liable for noncompliance regardless of whether the pipeline operator or the associated refinery commits the violation. Overlapping state and federal regulations of pipelines and refineries has created confusion amongst operators regarding what regulations apply to their facilities. Three federal agencies—the Pipeline and Hazardous Safety Administration (PHMSA), the Occupational Safety and Health Administration, and the Environmental Protection Agency (EPA) respectively—and a myriad of state agencies simultaneously …