发展煤矿井下选煤技术与装备的思考

阐述了在煤矿井下将采煤与选煤作业有机地融合为一体的必要性,分析了毛煤井下分选排矸的技术途径,指出了矸石资源化利用应注意的问题,并提出应及早立项开展研究开发煤矿井下选煤技术与装备的建议。

关于金融危机对中国煤矿采选行业的影响及应对策略探析

金融危机对全球经济影响深远,我国煤矿行业也受到了相应的影响,文章分析了当前金融危机如何传导到实体经济,导致煤炭市场急剧萎缩,价格急剧下滑,阐述了煤矿企业如何应对金融危机,尤其是在企业库存增加,生产开工率不足的情况下,从行业政策措施以及企业内部管理措施方面说明了煤炭企业要想成功应对这场危机,必须积累经验,在科学分析的基础上进一步提高金融危机对煤矿行业影响的认识,并通过采取一系列行之有效的应对措施从容面对。

环境会计信息披露影响因素研究——以煤矿采选行业为例

环境会计信息的披露是上市工业企业的重要信息披露内容,利益相关者可通过它了解企业环境污染问题及治理的状况。本文通过实证研究,分析近三年煤矿采选业上市企业的财务与非财务信息,发现环境会计信息披露指数(Environmental Disclosure Index,简称EDI)与公司资产规模和资产负债率呈正相关,与流通股占比呈负相关,而净资产收益率和独立董事占比对其影响不显著。

煤矿洗选厂系统智能化改造设计

在我国加快环保节能发展的大形势下,提升煤矿洗选厂的运作安全性、生产效率,更好地满足环境保护、节能生产要求,成为研究热点。本文以煤矿洗选厂为例,根据其实际情况和改造需求对无线网络信息系统平台、现场移动控制系统、智能监测控制系统三大主要板块提出了改造设计方案,旨在全面提升煤矿洗选厂的智能化、现代化、信息化水平。

煤矿洗选设备维护管理系统浅谈

煤矿洗选设备维护管理系统能够有效的提升设备使用效率、降低设备管理成本、提升洗选质量,本文对洗选设备维护管理系统进行了定义,并分析了其设计原则及目标,列举了主要模块及组成结构。

改造煤泥水系统 提高选煤厂综合效益

针对寺河矿选煤厂煤泥水系统存在的问题进行了技术改造 ,介绍了技术改造的措施和改造后的技术指标及社会效益、经济效益。

处理临涣选煤厂高浓度循环水的试验研究

介绍了对临涣选煤厂高浓度循环水进行处理的试验简况。该试验成功地降低了该厂循环水的浓度，大幅度地提高了浮选精煤的回收率，增加了经济效益。

一种基于PC机的煤泥浮选自动识别系统

介绍了一种基于PC机的煤泥浮选自动识别系统。系统采用了数字图象处理技术、自动监控技术,在586机的Windows平台上,用VC++编程实现,所得结论准确,值得推广。

三维协同设计在煤矿设计中的应用

随着信息技术的不断发展,工厂的数字化、智慧化成为可能和发展潮流。本文利用Bentley平台在煤矿设计中进行三维协同设计,为相关行业多专业一体化设计的三维协同设计提供参考。

煤矿洗选废水零排放处理技术研究与应用

随着环保意识的增强和环保法规的日益严格,煤矿洗选废水的处理与回用问题受到了广泛关注。本研究主要针对煤矿洗选废水处理难题,深入探讨了废水特性及其环境影响,系统研究了零排放处理技术,特别是高级氧化与膜分离等新技术。通过工程案例分析,验证了这些技术在提升废水处理效率、实现零排放目标方面的有效性。研究结果表明,综合运用多种先进技术,能够有效实现煤矿洗选废水的零排放目标,不仅降低了企业的环保风险和经济成本,还促进了水资源的循环利用和生态环境的保护。本文的研究为煤矿行业废水处理提供了科学依据和实践参考,对于推动煤炭行业的绿色转型和可持续发展具有重要意义。With the enhancement of environmental awareness and increasingly stringent environmental regulations, the treatment and reuse of coal mine washing wastewater has received widespread attention. This study mainly focuses on the treatment of coal mine washing wastewater, deeply explores the characteristics of wastewater and its environmental impact, and systematically studies zero-discharge treatment technology, especially new technologies such as advanced oxidation and membrane separation. Through engineering case analysis, the effectiveness of these technologies in improving wastewater treatment efficiency and achieving zero-discharge goals has been verified. The research results show that the comprehensive use of a variety of advanced technologies can effectively achieve the zero-discharge goal of coal mine washing wastewater, which not only reduces the environmental risks and economic costs of enterprises, but also promotes the recycling of water resources and the protection of the ecological environment. The research in this paper provides a scientific basis and practical reference for wastewater treatment in the coal mining industry, which is of great significance for promoting the green transformation and sustainable development of the coal industry.

Vanadium recovery from stone coal through roasting and flotation

A new process for vanadium recovery from stone coal by roasting-flotation was investigated based on the mineralogy. The process comprised four key steps： decarburization, preferential grinding, desliming and flotation. In the decarburization stage, roasting at 550 ℃ effectively avoided the negative effect of the carbonaceous materials in raw ore and generation of free CaO from calcite decomposition during roasting. Through preferential grinding, the high acid-consuming minerals were enriched in the middle fractions, while mica was enriched in the fine and coarse fractions. Through flotation, the final concentrate can be obtained with V2O5 grade of 1.07% and recovery of 83.30%. Moreover, the vanadium leaching rate of the final concentrate increased 13.53% compared to that of the feed. The results reveal that the decarburization by roasting at 550 ℃ is feasible and has little negative impact on mica flotation, and vanadium recovery from stone coal is conducive to reducing handling quantity, acid consumption and production cost.

Behaviors of vanadium and chromium in coal-based direct reduction of high-chromium vanadium-bearing titanomagnetite concentrates followed by magnetic separation

The reduction behaviors of FeO·V2O3 and FeO·Cr2O3 during coal-based direct reduction have a decisive impact on the efficient utilization of high-chromium vanadium-bearing titanomagnetite concentrates. The effects of molar ratio of C to Fe n(C)/n(Fe) and temperature on the behaviors of vanadium and chromium during direct reduction and magnetic separation were investigated. The reduced samples were characterized by X-ray diffraction(XRD), scanning election microscopy(SEM) and energy dispersive spectrometry(EDS) techniques. Experimental results indicate that the recoveries of vanadium and chromium rapidly increase from 10.0% and 9.6% to 45.3% and 74.3%, respectively, as the n(C)/n(Fe) increases from 0.8 to 1.4. At n(C)/n(Fe) of 0.8, the recoveries of vanadium and chromium are always lower than 10.0% in the whole temperature range of 1100-1250 °C. However, at n(C)/n(Fe) of 1.2, the recoveries of vanadium and chromium considerably increase from 17.8% and 33.8% to 42.4% and 76.0%, respectively, as the temperature increases from 1100 °C to 1250 °C. At n(C)/n(Fe) lower than 0.8, most of the FeO·V2O3 and FeO·Cr2O3 are not reduced to carbides because of the lack of carbonaceous reductants, and the temperature has little effect on the reduction behaviors of FeO·V2O3 and FeO·Cr2O3, resulting in very low recoveries of vanadium and chromium during magnetic separation. However, at higher n(C)/n(Fe), the reduction rates of FeO·V2O3 and FeO·Cr2O3 increase significatly because of the excess amount of carbonaceous reductants. Moreover, higher temperatures largely induce the reduction of FeO·V2O3 and FeO·Cr2O3 to carbides. The newly formed carbides are then dissolved in the γ(FCC) phase, and recovered accompanied with the metallic iron during magnetic separation.

Experimental Research on Desulfurization of Fine Coal Using an Enhanced Centrifugal Gravity Separator

A desulphurization experimental study under the effects of compounding physical force fields has been described for 〈 0.5 mm fine particles of high sulfur coal. A statistical test using the Box-Behnken Design of experiments was conducted to evaluate the effects of individual operating variables and their interactions on desulfurization of fine coal using an enhanced centrifugal gravity separator. A model describing the relation between desulphurization efficiency of pyrite sulfur and different operating variables has been designed. The interactions between different factors on the pyrite sulfur desulphurization efficiency have been analysed. The optimal test conditions for desulfarization are extracted from the Design-Expert 6.0 software. Finally, the pointed out. advantage of centrifugal gravity separation for fine coal is pointed out.

Study of Enhanced Fine Coal De-sulphurization and De-ashing by Ultrasonic Flotation

The feasibility of using ultrasound to enhance the performance of de-sulphurization and de-ashing during slime flotation was investigated. The Setararn C80 calorimeter, the contact angle gauge DCAT21 and an electrophoresis apparatus were used to study the surface nature of coal, pyrite and refuse before and after ultrasonic conditioning. The yield, ash and sulfur contents of equally sized coal slimes were also measured before and after ultrasonic conditioning. The results show that ultrasonic conditioning can drive the separation of pyrite and refuse from coal. After ultrasonic conditioning the hydrophobicity of coal and hydrophilicity of pyrite and refuse increase. The perfect index of flotation, the perfect index of de-sulphurization and the percentage of de-sulphurization increase by 22.51%, 25.36% and 2.49%, respectively. This study shows that ultrasonic conditioning can enhance the performance of de-sulphurization and de-ashing of coal flotation methods.

Modularized dry coal beneficiation technique based on gas-solid fluidized bed

A 40-60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide-size-range magnetite powder （0.3-0.06 ram） and 〈1 mm fine coal were numerically studied. The simulation results show that the fluidization performance of the wide-size-range medium-solid bed is good. The separation performance of the modularized system was then investigated in detail using a mixture of 〈0.3 mm magnetite powder （mass fraction of 0.3-0.06 mm particles is 91.38 %） and 〈1 mm fine coal as solid media. The experimental results show that at separation densities of 1.33 g/cm^3 or 1.61 g/cm^3, 50-6 mm coal can be separated effectively with probable error, E, values of 0.05 g/cm^3 and 0.06 g/cm^3, respectively. This technique is beneficial for saving water resources and for the clean utilization of coal.

Low Density Dry Coal Beneficiation Using an Air Dense Medium Fluidized Bed

For the production of low ash content clean coal, separation at low density is required for some raw coals.Based on analyzing the fluidizing characteristics of magnetic-pearls with a specific size clistribution and formation mechanism of a microbubble fluidized bed, optimal technological and operating parameters suitable for low density coal separation were determined. The experimental results show that an air dense medium fluidized bed with low den-sity can be formed using magnetic pearls as medium solids, which can efficiently beneficiate coal of 6-50 mm size with a probable error Ep value of 0.05 at a separating density of 1.44 g/cm^3.

Beneficiation of an Indian non-coking coal by column flotation

Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications such as the fuel for integrated gasification combined cycle plant （IGCC）, the ash content in the coal should preferably be below 15 %. Indian coals are characterized by high inter-grown ash content mainly due to ＇drift origin＇ of Gondwana formation in Permian age. This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals. A non- coking coal sample of vitrinite type from India was ground to 44 ~tm （dso） and subjected to column flotation to improve its quality. The non-coking coal analyzing 34.6 % ash, 26.2 % volatile matter, 1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters, namely, froth depth, superficial feed velocity and superficial air velocity. The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.

Particle Residence Time in Column Flotation Based on Cyclonic Separation

The cyclonic static micro-bubble column flotation (FCSMC) is an effective separation device for fine particle treatment. The high mineralization rate and short flotation time of this equipment can be attributed to its unique cyclonic force field. It also has been observed that the presence of a cyclonic force field leads to a lower bottom separation size limit and a reduction of unselective entrainment. The collection zone of the column is considered to consist of two parts,a column separation zone and a cyclonic zone. Total recovery of the collection zone was developed. For our study,we analyzed the particle movement in the cyclonic zone. Particle residence time equations for the cyclonic zone were de-rived by force analysis. Results obtained in this study provide a theoretical foundation for the design and scale-up of the FCSMC.

Moving Behavior of an Object in Gas-Solid Fluidized Beds

The settling behavior of coarse particles in a gas-solid fluidized bed was experimentally studied by using magnetic tracer. It is well known that the calculation of terminal velocity is of interest in dense medium separation. However, this problem has not been completely solved up to now. In this work, the terminal velocity of an object mov-ing in a gas-solid fluidized bed was experimentally measured and theoretically calculated. The experimental results in-dicated that the plastic viscosity and yield stress of the bed increase as the size of fluidized particles increases, but it varies little when some coarser particles are mixed with the fluidized particles. The resistance to a rising object was an order magnitude greater than that to a settling object. The efficient buoyancy on a flaky object, which lies flatly on the gas distributor, was much less than that calculated by the Archimedes principle. The object does not always rise or set-tle with minimal projective area owing to radial motion of the fluidized particles. But in the lower part of the bed, the bar-shaped objects were likely with minimal projective area rising or settling.