油页岩反采技术研究与实践

介绍了北皇煤矿下部煤层回采后油页岩赋存的地质条件及其变化,研究了矿压显现规律、巷道变形规律,阐述了油页岩反采技术实践,并分析了取得的技术经济效益。

“Z”型留巷和反采在工作面过断层的应用

炮采工作面过断层大致有两种方法:一是断层落差较小时采取挑顶破底,平推硬过;二是断层落差较大时提前做好跳压切眼,回采至断层处后直接收作,在跳压切眼重新安装工作面,跳过断层继续向前回采。采用上述两种方法都存在一定的弊端,提出了分段"Z"型留巷和跳压反采的回采方式,并对该方式进行了系统分析,经皖北煤电百善煤矿68南翼煤柱工作面中应用,取得了巨大的经济效益。

分段“Z”型留巷和跳压反采过断层在百善矿的实践

炮采工作面过断层大致有两种方法:一是断层落差较小时进行平推硬过,即是采取挑顶破底,平推硬过;二是断层落差较大时进行跳压回采,即是提前做好跳压切眼,回采至断层处后直接收作,在跳压切眼重新安装工作面,跳过断层继续向前回采。上述两种方法都存在一定的弊端,现提出分段"Z"型留巷和跳压反采的回采方式,对该方式进行了系统分析,投入到68南翼煤柱工作面中应用,并取得了明显的经济效益。

油页岩反采采后短期内送巷技术研究

该文是根据矿井生产接续的需要,首先从软岩矿山压力控制角度,论证了反采采后短期内送巷技术的可行性,介绍了反采小煤柱护巷巷道支护参数,并对反采采后短期内送巷效果进行了监测分析。通过该项技术研究,缓解了采掘接续紧张的局面,确保了矿井安全稳定生产。

煤层反采过程中的裂隙漏风及处理

我国东部地区矿产资源形势严峻,多个企业反采以往遗漏的煤层,创造经济效益。然而,以往的上行顺序采煤判别方法,没有对裂隙漏风做详尽的研究,使得判别方法不合理。分析并介绍了煤层反采过程中的裂隙漏风问题,提出了以往判别法中的不合理之处,并对其进行了初步修改。对于现有煤矿存在的煤层反采裂隙漏风问题提出了系统的解决方法,为煤层反采工作起到一定的指导作用。

综采工作面“跳采反排水”法应用初探

针对综采工作面在不同回采情况下,采取不同排水方式所取得的效果进行了说明,阐述了传统排水的弊端,并以实际应用论证了“跳采反排水法”的可行性,详细介绍了“跳采反排水”法收到的成效。

低渗透油田加密调整注采井距适配新方法

史深100沙三中低渗透油田反九点注采井网在加密调整过程中,开展了技术极限井距、经济极限以及经济合理井距研究。针对低渗透油田储层厚度变化大、储量丰度不均匀、储层非均质性强的特点,建立了考虑油层厚度、有效渗透率等因素下的注采井距优化图版;针对现注采井网井距不规则性,提出了新钻井点位置、压裂改造半缝长的确定方法,保障了井网加密调整的经济技术可行性,形成了低渗透油田井网加密调整过程中注采井距适配技术模式。

大采高综采技术在煤_1油页岩面的应用与实践

大采高综采技术在煤1油页岩反采工作面的生产实践,使煤1油页岩反采工作面采高由原来的3.0m提高到4.0m,取得了巨大的技术经济效益;为今后煤1油页岩的开采指明了方向,保持了矿井产量的稳定和可持续发展,实现了矿井陆地与海域采场并举的战略格局。

复杂开采条件下采煤工作面的综合防灭火实践

文章以北皂矿1105工作面为例,分析了反采区域二分层开采综放工作面存在的自然发火隐患,介绍了在复杂条件下采取的综合防灭火措施。

Evaluation of PS-DInSAR technology for subsidence monitoring caused by repeated mining in mountainous area

The high resolution Terra SAR-X dataset was employed with DIn SAR and persistent scatterer interferometry（PSI） technique for subsidence monitoring in a mountainous area. For DInS AR technique, the generally used SRTM and relief-DEM, which was derived from aerial topographic map, were used to evaluate the influence of external DEM. The results show that SRTM could not fully compensate the complex topography of the research area. The corner reflectors installed during the acquisition of SAR dataset were used to estimate the accuracy of geocoding. The terrain corrected geocoding results based on relief-DEM were much better than using SRTM, with the root mean square error（RMSE） being 6.35 m in X direction and 11.65 m in Y direction（both in UTM projection）, around one pixel of the multilooked intensity image to be geocoded. For PSI technique, the results from time-series analysis of multi-baseline differential interferograms were integrated to restrict only persistent scatterer candidates near the boundary of subsiding area for regression analysis. The results demonstrate that PSI can refine the boundary of subsidence, which could then be used to derive some angular parameters to help people to learn the law of subsidence caused by repeated excavation in this area.

露天铁矿松散边坡内含水粉细沙层的剥离方法

赵店子铁矿在露天开采中遇到了含有含水粉细沙层的松散覆盖层。生产中应用液压反铲 -汽车采装及分条剥离、超前疏干的剥离工艺较好的解决了松散覆盖层的剥离问题 ,取得了较好的经济效果。文中详细论述该法的使用情况 。

ultiscale full-waveform inversion based on shot subsampling

Conventional full-waveform inversion is computationally intensive because it considers all shots in each iteration. To tackle this, we establish the number of shots needed and propose multiscale inversion in the frequency domain while using only the shots that are positively correlated with frequency. When using low-frequency data, the method considers only a small number of shots and raw data. More shots are used with increasing frequency. The random-in-group subsampling method is used to rotate the shots between iterations and avoid the loss of shot information. By reducing the number of shots in the inversion, we decrease the computational cost. There is no crosstalk between shots, no noise addition, and no observational limits. Numerical modeling suggests that the proposed method reduces the computing time, is more robust to noise, and produces better velocity models when using data with noise.

An improved particle filtering algorithm based on observation inversion optimal sampling

According to the effective sampling of particles and the particles impoverishment caused by re-sampling in particle filter,an improved particle filtering algorithm based on observation inversion optimal sampling was proposed. Firstly,virtual observations were generated from the latest observation,and two sampling strategies were presented. Then,the previous time particles were sampled by utilizing the function inversion relationship between observation and system state. Finally,the current time particles were generated on the basis of the previous time particles and the system one-step state transition model. By the above method,sampling particles can make full use of the latest observation information and the priori modeling information,so that they further approximate the true state. The theoretical analysis and experimental results show that the new algorithm filtering accuracy and real-time outperform obviously the standard particle filter,the extended Kalman particle filter and the unscented particle filter.

An evaluation of deep thin coal seams and water-bearing/resisting layers in the quaternary system using seismic inversion

Non-liner wave equation inversion,wavelet analysis and artificial neural networks were used to obtain stratum parameters and the distribution of thin coal seams.The lithology of the water-bearing/resisting layer in the Quaternary system was also predicted.The implementation process included calculating the well log parameters,stratum contrasting the seismic data and the well logs,and extracting,studying and predicting seismic attributes.Seismic inversion parameters,including the layer velocity and wave impedance,were calculated and effectively used for prediction and analysis.Prior knowledge and seismic interpretation were used to remedy a dearth of seismic data during the inversion procedure.This enhanced the stability of the inversion method.Non-linear seismic inversion and artificial neural networks were used to interpret coal seismic lithology and to study the water-bearing/resisting layer in the Quaternary system.Interpretation of the 1～2 m thin coal seams,and also of the water-bearing/resisting layer in the Quaternary system,is provided.The upper mining limit can be lifted from 60 m to 45 m.The predictions show that this method can provide reliable data useful for thin coal seam exploitation and for lifting the upper mining limit,which is one of the principles of green mining.

Leaching kinetics in cyanide media of Ag contained in the industrial mining-metallurgical wastes in the state of Hidalgo, Mexico

The leaching kinetics in cyanide media of the silver contained in the Dos Carlos waste tailings at the City of Pachuca de Soto, Hidalgo State, Mexico were carried out. The used material contained the following chemical composition: 56 10-6of Ag, 0.6 10 6of Au and 70.43%(by weight) of SiO2; 7.032%(by weight) of Al2O3; 2.69%(by weight) of Fe; 0.46%(by weight) of Mn; 3.98%(by weight) of K2O; 3.34%(by weight) of CaO; 2.50%(by weight) of Na2O; 0.04%(by weight) of Zn; 0.026%(by weight) of Pb. The mineralogical phases present were the following: Silica, albite, argentite, berlinite, orthoclase, potassium jarosite, and natrojarosite. In the leaching kinetics in cyanide media, and under the studied conditions,the effect of the CN concentration on the reaction rate has no effect on the whole process of alkaline cyanidation, of which the reaction order is n 0. Temperature has an effect on the cyanidation rate of the reaction, with an activation energy of 47.9 KJ/mol. At the same time, when the particle size decreases there is an increase in the reaction rate, which is inversely proportional to the particle diameter; when increasing the NaOH concentration there is an increase in the reaction rate Kexp, with a reaction order(n) of 0.215 under the studied ranges.

Progress in designing effective photoelectrodes for solar water splitting

Photoelectrochemical(PEC)water splitting process is regarded as a promising route to generate hydrogen by solar energy and at the heart of PEC is efficient electrode design.Great progress has been achieved in the aspects of material design,cocatalyst study,and electrode fabrication over the past decades.However,some key challenges remain unsolved,including the most demanded conversion efficiency issue.As three critical steps,i.e.light harvesting,charge transfer and surface reaction of the PEC process,occur in a huge range of time scale(from10-12s to100s),how to manage these subsequent steps to facilitate the seamless cooperation between each step to realize efficient PEC process is essentially important.This review focuses on an integral consideration of the three key criteria based on the recent progress on high efficient and stable photoelectrode design in PEC.The basic principles and potential strategies are summarized.Moreover,the challenge and perspective are also discussed.

Macauba as Promising Substrate for Crude Oil and Biodiesel Production

The preparation of macauba fruits （Acrocomia aculeate （Jacq.） Lodd. ex Martius） both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were characterized for their resulting oils. Experimental design was carried out to study the transesterification of each oil to obtain the concentrations of ethanol and catalyst that would provide the best biodiesel yield. A higher amount of biodiesel was produced from the best conditions to evaluate some characteristics as specified by ANP （National Agency of Petroleum, Natural Gas and Biofuels）. The results showed a variation in the fruits composition and different characteristics presented by the pulp and kernel oil. It was possible to define technological steps to obtain oil from the fruits of macauba and find the optimal conditions to biodiesel production, concentration of catalyst 4.42% and 5% and 13.3：1 and 9：1 ethanol：oil molar ratio to kernel oil and pulp oil, respectively.

Optimization design of deep lean-ore mining and safety evaluation

In order to settle the mining optimization design and safety problem of the above 1 150 m pillar of No.1 ore-body in No.H Mining Jinchuan, the lean-ore above 1 250 m, the 1 150 m horizontal pillar and the ore-body below 1 100 m regarded as research objects based on the original design project, and nine calculation schemes on different mining sequence and different fill body strength were put forward based on cement-sand ratio of 1 ： 4, 1： 12 and 1 ： 24. Calculation parameters were got by the back analysis method of field monitoring data, and the FLAC2D program was applied to compute for these schemes, stress and displacement of ground settlement, shaft and stope roof were analyzed, and some conclusions were got. Results show that the intensity of filling body and the mining technique have very important effect on controlling settlement and stability of surrounding rock; Developing of lean ore have some influences to the 16th return air filling shaft, especially for 1 500--1 400 m of the shaft; The best project is the first project. This research supply some technique references and safety appraisals for the mining of lean-ore of No.II Mining Jinchuan.

Research on inversion high mining pressure distribution and technology of preventing dynamic disasters by MS monitoring in longwall face

Under two rock strata combination conditions, over 10,000 microseismic events were received with microseismic location monitoring technology which possessed by the author＇s studying team, used in fully mechanized coal face of Huafeng Mine of Xinwen Coal Mining Group Co., Shandong Province. On the basis of the achievement of the location results, the conclusions were drawn as follows： On the basis of the achievement of 3D strata fracturing situation and the section plane of microseimic events in different areas, the relationship between spatial structure of overlying strata and mining pressure field was found, and we might describe distribution range of dynamic pressure of advance pressure and lateral stress around long face, and range of structure ad-tivation. Quantitative guidance to prevent dynamic disasters was provided. The practice in coal mine got a effective results. According to the FLAG3D soft numerical simulation of diameter drilling hole （the diameter is 300 mm） to relieve pressure in specified geological condition in Huafeng Mine, the right distance of two dirlls is 2.5 m and the right depth is 12 m. The research pro-vided basic guiding and practical experiences for the underground microseismic monitoring and disaster prevention in side slopes or tunnels engineering.

Construction of universal calibration model for levofloxacin injections by fiber-optic transmittance-reflectance near-infrared spectroscopy

The general strategy and method of constructing universal calibration model for levofioxacin injections by near-infrared spectroscopy have been investigated and discussed. Firstly, a constant-temperature homogeneous liquid calibration model for levofloxacin hydrochloride injections with the same composition but different active principal ingredient （API） content was established as the basic unit for universal model. Then, samples of levofloxacin hydrochloride injections containing propylene glycol or levofloxacin lactate injections were added to develop a primary constant-temperature liquid universal model. Temperature- amended final universal model was established to apply to samples under different temperatures. The final model was built from 61 calibration samples and 77 validation samples. The value of the root mean square error of cross validation （RMSECV） and coefficient of determination （r2） of leave-one-out cross-validation （LOOCV） were 0.792 and 0.9993, respectively, the root mean square error of prediction （RMSEP） of test set validation （TSV） was 0.87, and the average relative deviation was 1.44%. According to the ICH guidelines, the universal calibration model was evaluated. Based on the experimental statistical results, the recommended number of calibration samples for a constant-temperature homogeneous liquid quantitative model was no less than 15.