Sustainability Commons^™

Perchlorate Behavior In The Context Of Black Carbon And Metal Cogeneration Following Fireworks Emission At Oak Lake, Lincoln, Nebraska, Usa, Manish Kumar, Daniel D. Snow, Yusong Li, Patrick Shea

Nebraska Water Center: Faculty Publications

The imprints of fireworks displays on the adjacent water body were investigated from the perspective of cogeneration of black carbon, metals and perchlorate (ClO₄^–). In particular, the mixing and dissipation of ClO₄^– were studied at Oak Lake, Lincoln, Nebraska, following fireworks displays in 2015 and 2016. Following the display, ClO₄^– concentration in the water increased up to 4.3 μg/L and 4.0 μg/L in 2015 and 2016, respectively. A first-order model generally provided a good fit to the measured perchlorate concentrations from which the rate of dissipation was estimated as 0.07 d^–1 in …

Evaluating Future Reservoir Storage In The Rio Grande Using Normalized Climate Projections And A Water Balance Model, Nolan T. Townsend

Earth and Planetary Sciences ETDs

We develop and implement new tools for assessing the future of surface water supplies in downstream reaches of the Rio Grande, for which Elephant Butte Reservoir is the major storage reservoir. First, a normalization procedure is developed to adjust natural Rio Grande streamflows simulated by dynamical models in downstream reaches. The normalization accounts for upstream anthropogenic impairments to flow that are not considered in the model, thereby yielding downstream flows closer to observed values and more appropriate for use in assessments of future flows in downstream reaches. The normalization is applied to assess the potential effects of climate change on …

Breakdown Mechanisms In Iron Caves. An Example From Brazil, Marcelo R. Barbosa, Allan D.F. Da Silva, Rafael G. De Paula, Georgete M. Dutra, Airton Barata, Iuri V. Brandi, Chrystophe R.P. Da Silva, Robert A. Osborne

International Journal of Speleology

An iron cave in the vicinity of a mine in Carajás, Brazil, was selected to be mined within an assisted elimination project, planned to control all mine advancement operations towards the cave along with a strict speleological physical monitoring. It allowed, in a pioneering way, the recording of events in the cave from the first signs of damage until to the total collapse of the cave. The project lasted four years and it was possible to identify and describe four breakdown mechanisms in iron caves: Fragment downfall, Block downfall, Controlling structure reactivation, and Open discontinuity movement. The mechanisms occurred independently …

Crop And Climate Suitability For Irrigated Agriculture In The Midlands Area Of Western Australia, 2nd Edition, Leon Van Wyk

Resource management technical reports

The Midlands groundwater and land assessment is a $4.7 million Water for Food project. Its aim is to confirm groundwater availability at one or more focus areas that may form precincts of 2000–3000 hectares suitable for intensive irrigated horticulture. This report forms part of this project.

Firstly, this report describes the climate of the Midlands study area and highlights the subtle differences between the two selected focus areas, Irwin and Dinner Hill. It discusses the importance of climate in determining crop suitability. We also investigated the following additional factors that determine crop suitability: water quality, water quantity, land capability (soils) …

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2019, Natalie Umphlett, Rezaul Mamood, Paul Flanagan, Emily Brown, Gannon Rush, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the director........................................1

Staff spotlight...........................1

Spirit Lake workshop..............2

Product highlight....................3

Outreach events......................3

Research highlight..................4

Update on regional climate conditions..................................4

Northern Plains drought assessment................................5

Recent and upcoming travel and activities.............................6

Droughtscape, Fall 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

Ranchers delayed response to drought

Drought Monitor celebrates 20 years

Drought Monitor state impact tables

Directorcontributesto U.N.droughtproject

Updated Drought Risk Atlas

New fact sheet lists recovery resources

Droughtscape, Summer 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

Quarterly drought summary

Quarterly drought impacts

NDMC welcomes African visitors

Ready for Drought game debuts

U.S. Virgin Islands added to USDM

Australian programmer visits NDMC

Upcoming events

Partnerships with NDMC extended

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

The Development Of Seismic-While-Mining Detection Technology In Underground Coal Mines, Cheng Jianyuan, Qin Si, Lu Bin, Wang Baoli, Wang Ji

Coal Geology & Exploration

The explosive source of underground seismic exploration in coal mines is greatly affected by the control of pyrotechnics and cannot realize the monitoring and early warning of dynamic geological disasters in coal mining. Seismic-while-mining(SWM) is a new technique based on shearer as a seismic source underground. The paper reviewed the research status of SWM technique at home and abroad, introduced the SWM's principle and its unique advantages. According to some pilot experiments of SWM, the results show that the shearer can be used as a seismic source because it has the character of strong excitation energy, wide frequency band, safety, …

Method Of Transparent Working Face Based On Dynamic Detection Of Cross Hole Seismic Subdivision, Lu Bin

Coal Geology & Exploration

Transparent working surface is an important part of intelligent coal mining. It provides detailed geological structure information of working face for intelligent coal mining. This paper proposes a working surface exploration method based on segmented and dynamic cross-hole seismic, which can realize progressive fine detection of coal working face. The method is a new development with seismic while mining, which is using the coal cutter as seismic source. The main idea is to image the working face segmented by deploying some detectors in a series of horizontal holes parallel to the long wall. The method performs fine imaging on the …

Simulation Of Seismic-While-Mining With Shearer As Source Of Fully Mechanized Mining Face, Jin Dan

Coal Geology & Exploration

In order to analyze the wave field characteristics of seismic-while-mining data excited by coal cutter as seismic source, forward simulation was used to calculate seismic data. We transform the cutting mode of spiral drum and the stress of drum into the force function of seismic source, which is added to the wave equation in the form of load distribution at different time and location. Wave equation is solved by high-order staggered-style finite difference method. Finally, the seismic data obtained by numerical simulation show that shear wave energy is very strong and press wave energy is very weak in the wave …

Geological Evaluation Model For Site Selection Of Underground Coal Gasification Without Well In Jinghai Coal-Bearing Area, Tianjin, China, Wang Zhigang, Fu Xiaojin, Liang Jie, Cao Jian, Jiang Shengguo

Coal Geology & Exploration

Based on the 4 factors such as exploration status, coal seam, coal quality and hydrological conditions, using the secondary fuzzy comprehensive evaluation method, the geological evaluation model without well was built. In order to verify the applicability of the model, the material balance by law of conservation of mass was carried out and the results compared with the test results of indoor model was got. This research suggests that the weight of geological conditions affecting underground coal gasification without well is exploration status > conditions of coal seam > hydrological conditions > coal quality, the area with comprehensive score higher than 70 is …

Study On The Biodegradation Of Guanidine Gum By Methanogens In Coal Seam, Li Yunsong, Guo Hongyu, Fu Chaoyong, Zhao Guojun, Xia Daping

Coal Geology & Exploration

The problem of low temperature breaking of guanidine gum fracturing fluid is related to the effect of coal seam penetration. In order to explore the effect of methanogenson the biodegradation of guanidine gum, Inner Mongolia some coal mine lignite were collected to prepare samples of coal samples, and the enriched fresh mine water was used as the bacteria source. The biological methane metabolism experiments of guanidine gum + coal were used to characterize the biodegradability of methanogens to guanidine gum, with the total gas production, CH₄ concentration, guanidine gum molecular functional groups and C and H elements content changes. …

Productivity Prediction Of Hypotonic Cbm Test Well In Jiaozuo Mining Area Under Hydraulic Fracturing, Wang Zhirong, Yang Jie, Chen Lingxia, Guo Zhiwei

Coal Geology & Exploration

In order to explore the permeable mechanism and the output law after fracturing of CBM in the "three soft" coal seam(soft coal, soft roof and soft bottom) of Jiaozuo under hydraulic fracturing, Based on the permeable model of reservoir fracture, considering the influence of fracture porosity on permeability after fracturing, a reservoir fracture penetration model was established, the application and analysis of the test well was carried out to obtain the characteristics of pressure cracks such as length, width, permeability and reservoir parameters after fracturing. Through the comprehensive analysis of isothermal adsorption curves and historical fitting, the recovery rate of …

Simulation And Test Of Enhancement Of Gas Drainage Through Co2 Injection Into Coal Seam Of Low Permeability, Bai Gang, Zhou Xihua, Wei Shiping, Fan Chaojun, Li Xueming

Coal Geology & Exploration

In view of the difficulty of gas extraction and low drainage efficiency in coal seam of low permeability, based on multi component gas competitive adsorption of CO₂-CH₄, simulation and test for improving seam gas extraction rate through CO₂ injecting CO₂ into coal seam were carried out. A fluid-solid coupling model considering gas-water phases and Klinkenberg effect of CO₂ injection into coal seam for enhancement of gas drainage was established, parameters of gas pressure, gas content and gas extraction rate after coal seam CO₂ injection were analyzed by using COMSOL software and applied …

Genesis And Geochemical Characteristics Of Coalbed Methane From Taiyuan Formation In Sijiazhuang Mine Field Of Yangquan Mining Area, Yu Zhenfeng, Hao Chunsheng, Yang Changyong, Yao Jinbao, Wang Wei, Ji Changjiang

Coal Geology & Exploration

In order to study the geochemical characteristics and the genesis of CBM of Sijiazhuang mine field in Yangquan mining area, the in-site desorption test of coal core samples from the main gas-producing seams(seams 8, 9 and 15) from Permo-Carboniferous Taiyuan Formation was carried out systematically, gas samples were collected to conduct component and carbon isotope analysis. The results indicated that the gas content of seam 8 was higher than that of seam 9, on the plan the gas content of seam 15 was uneven, in some parts there was almost no gas. During the whole desorption, the gas component content …

Effects Of Pressure Drop Funnels Model Of Different Shapes On Cbm Well Productivity, Hu Haiyang, Jin Jun, Zhao Lingyun, Chen Jie, Gu Jiaoyang

Coal Geology & Exploration

In order to study the effect of pressure drop funnel shapes on CBM well productivity, the change law of pressure and the shape of pressure drop funnel in different drainage stages of CBM wells were discussed, the mathematical models of pressure drop funnel were established, the concept of "desorption coefficient" and "effective desorption coefficient" for coal reservoir were proposed to quantitative study desorption effect of the coal reservoir. Taking a CBM well in the west of Guizhou as an example, the research results show that the logarithmic function model of pressure distribution of radial flow is difficult to accurately reflect …

Formation Mechanism Of Coal Seam Aquifer And Water Hazard Control Technology, Wang Hao

Coal Geology & Exploration

Coal seams occur in Peat formation formed by sediments, often used as aquiclude or aquitard in coal production. However, in Barapukuria coal mine in Bangladesh, No.VI coal seam is rich in water, shows a typical hydrogeological phenomenon that the coal seam becomes an aquifer, which is rare in coal mining process both in China and abroad. From the formation mechanism of coal and the microstructure and tectonic development characteristics of coal, the structure of rich in water of coal was revealed. Based on MTS815 rock mechanics test system, the permeability of No.VI coal was tested, and the internal structure of …

Water Yield Analysis Of Underground Drainage Boreholes On The Basis Of Logarithmic Normal Distribution, Ma Lianjing, Zhao Baofeng

Coal Geology & Exploration

In order to analyze the distribution rule of water flow from underground drainage borehole in coal mines, histogram, Q-Q chart and nonparametric tests were used to test the logarithmic normal distribution model for water flow from underground drainage borehole in typical working face, and the nonlinear regression model was fitted. Combined with hydrogeological conditions, the parameters in the model were analyzed. The result shows that water flow from underground drainage boreholes in working face obeys the lognormal distritution. The logarithmic mean and standard deviation of water flow from drainage borehole of typical working face have a positive linear dependence relation …

Prediction Of The Height Of Water Flowing Fractured Zone Under Subcritical Mining Based On Dimensional Analysis, Lou Gaozhong, Guo Wenbing, Gao Jinlong

Coal Geology & Exploration

In order to accurately predict the height of water flowing fractured zone under subcritical mining, mining thickness M, mining depth H, inclined length of working face L, dip angle of coal seam α, overburden mechanical properties R, overburden structure characteristics S were selected as the main influencing factors on the height of water flowing fractured zone under subcritical mining. Dimensionless relations between the height of water flowing fractured zone and M, H, L, α, S were established by dimensional analysis. Based on 30 sets of measured data, the optimal function relation of dimensionless relation was …

Ga_Svm_Adaboost Model For Prediction Of Earthquake-Induced Sandy Soil Liquefaction, Mao Zhiyong, Huang Chunjuan, Lu Shichang

Coal Geology & Exploration

In order to predict the liquefaction of sand, the seismic intensity, groundwater level, covering thickness, standard number, average particle size, landform, soil quality and inhomogeneity coefficient are selected as influencing factors. Genetic algorithm(GA) is used to optimize the parameters of support vector machine(SVM) by using correlation analysis and factor analysis model, and combining with Adaboost iterative algorithm, the GA_SVM_Adaboost model for predicting the liquefaction of sand is established. 329 sets of survey data of sandy liquefaction site in Tangshan earthquake were used to train the model, and 68 samples of sandy liquefaction data were predicted by using the good model. …

Comparison Of Dissolution Characteristics Of Organic Matter In Coal Gangue Of Different Geological Time, Sun Yanfang, Zhao Li, Luo Shaohe, Zhang Lei, Sun Chao, Li Bowen

Coal Geology & Exploration

Taken the unweathered coal gangues obtained from the Jurassic coalbed of Bulianta mine and the Car-boniferous-Permian coalbed of Baode mine located in Shendong mining area as the research subjects, the dissolution characteristics of organic matter in two kinds of coal gangues were studied comparatively through soaking experiments, and combined with three-dimensional fluorescence spectrometry and parallel factor analysis. It is significant for the underground reservoir to study mechanism of water treatment in coal mining areas. These results indicate that the total ion concentration in DOM sample of coal gangue of Bulianta mine is higher than that of Baode mine due to …

Effect Of Clay Content On Shear Strength Of Loess, Wang Li, Li Xi'an, Hong Bo, Du Shaoshao, Zhang Hangbo, Zhao Ning

Coal Geology & Exploration

The experimental research about effect of different clay content on shear strength of loess was carried out to reveal the influence of clay content on shear strength and its microscopic mechanism, and then a scientific basis for engineering practice of loess was provided. Self-made wet sieve device under negative pressure was applied to screen loess samples with different clay content. Different clay content of the loess samples were made to the same dry density, but with different moisture content using static pressure method, and then were taken direct shear test. The results show that with the increase of moisture content, …

Feasibility Test Of Roof Resistivity Monitoring For Super-High Mining Face, Lu Jingjin, Li Deshan, Wang Bingchun

Coal Geology & Exploration

The failure of roof overburden is one of the main reasons for water inrush in mining working face. Roof resistivity monitoring by mine electrical method can be used to detect overburden failure dynamically. However, roof resistivity monitoring for super-high mining face has many problems, such as audio electromagnetic signal by conventional methods is difficult to penetrate through wide working face, burying of roof monitoring electrodes is difficult, monitoring electrode in the roof of air return lane is hard to protect, and so on. In order to solving these problems, feasibility study of roof resistivity monitoring for super-high mining face is …

Experimental Study On The Influence Of Well Inclination Angle Of Coalbed Methane Well On The Cementation Strength Of Cement-Formation Interface, Gu Jun, Li Linwei, Sun Dexing

Coal Geology & Exploration

In order to control the problem of water channeling in the process of coalbed methane(CBM) production, based on the self-designed test device and method, the test data of the shear strength at cement-aquiclude interface (CAI) is obtained under the conditions of well inclination of 0°, 30°, 60° and 90°. The mechanism of the influence of inclination angle on the shear strength at CAI is analyzed. The results show that the shear strength at CAI decreases with the increase of the inclination angle. The reason is that as the inclination angle increases, the upper part of the mud cake ring becomes …

Reasonable Length Of Working Face 11-101 During Mining Above Confined Aquifer In Tuanbai Mine, Li Gang, Zhang Kai, Su Junhui, Wang Jinbo

Coal Geology & Exploration

The working face 11-101 of Tuanbai coal mine in Huozhou, Shanxi Province is exploited above aquifer. In order to prevent floor water inrush accidents during mining, research combination of elasto-plastic theory, on-site measurement and numerical simulation was carried out to analyze the development rule of failure depth of the floor, then the reasonable length of the mining face under this condition was determined. The result shows that with the advancement of working face, the bottom plate of lagging working face is stretched and destroyed at about 6 m behind the lagging working face, and the bottom plate has a wedge …

Development Of Data Acquisition And Control Software For Seismic Monitoring With Mining, Duan Jianhua, Wang Yunhong, Wang Baoli

Coal Geology & Exploration

Seismic monitoring with mining can continuously detect and real-time predict geological anomalies in front of work, it has become a research hotspot in recent years, but at present, there is no equipment that can carry out seismic monitoring with mining in coal mine.Therefore, the development of seismic monitoring equipment with mining has become a top priority. In order to solve this problem, based on the MFC development framework, a set of seismic monitoring data acquisition software is developed. A three-month joint survey was carried out indoors and outdoors, and a three-month comprehensive trial operation was carried out in Yanjiao Coal …

Experiment On Methane Displacement In Coalbed By Supercritical Carbon Dioxide, Wu Di, Liu Xueying, Sun Keming, Xin Liwei, Miao Feng

Coal Geology & Exploration

Using self-made experimental system, experiments were performed on coal samples to study supercritical CO₂ seepage, adsorption and CH₄ displacement by supercritical CO₂. Experimental results show that permeability and adsorption of supercritical CO₂ in coal increase with CO₂ pressures. Pressures and temperatures of CO₂ influence the values of displaced CH₄. Values of displaced CH₄ increase by average 0.076 cm³/g and sweep efficiency rises by 17%-23% with the CO₂ pressure increasing from 8 MPa to 12 MPa, while displacement volume decreases linearly. With the temperature rising by 10℃, sweep …

The Matching Of Gas Production Curve Characteristic And Reservoir Conditions In Vertical Coalbed Methane Wells, Han Wenlong, Wang Yanbin, Liu Du, Chang Hong, Ding Tao

Coal Geology & Exploration

The matching of coalbed methane(CBM) production curve type and geological conditions directly affects the gas production. Based on dividing gas production curves types of vertical CBM wells in the southern block of Shizhuang in Qinshui basin over 4 years, the characteristics of gas production curve were analyzed. The matching of gas production curve with reservoir parameters was further analyzed. The paper discovered and divided the gas production curve into four types:type of fast rising of single peak, type of stable rising of single peak, bimodal type of being low later and bimodal type of being high later. The original permeability, …

The Seepage Characteristics Of A Single Well Dewatering From An Unconfined Aquifer Bottom, Li Yang, Wang Wenxue, Xiao Hang, Sun Yi, Wang Yun, Di Mengna

Coal Geology & Exploration

Dewatering from an aquifer bottom for drain and depressurization is one common method to ensure safety mining. This method is significantly different from pumping from the ground. In order to study the seepage characteristics of the dewatering hole(well), the seepage characteristics of a single well dewatering from an unconfined aquifer bottom was taken as an example and studied using numerical simulation method. The results show that when l_w<l_c, the pore water pressure above the dewatering well is greater than zero, which presents the rule of increasing first then decreasing from bottom to top, and the seepage …