高硫煤矸石中回收黄铁矿的可选性研究

以晋城王台矿区的高硫煤矸石为研究对象,在跳汰粗选的基础上,采用实验室摇床和水介旋流器对煤矸石样品进行了可选性试验研究。结果表明,经过初步富集的煤矸石样品,通过摇床和水介旋流器分选均可获得品位大于32％的合格硫精矿,硫的回收率达到80％以上。     

关于煤炭可选性基础试验体系的应用

介绍了三种选煤基础试验体系的试验方法,简易型试验体系适用于地质部门,常规型试验体系适用于选煤厂设计,转筒型试验体系适用于设计、生产管理和科研等多种部门;列举了目前已有的选煤试验方法标准。     

Comparison of leachable trace element levels in coal gasifier ash with levels in power plant ash

The levels of 14 trace elements in leachates from three types of ash of a common origin coal were compared. The study was conducted over a one year period at the Kosovo plant in Obilic, Yugoslavia comparing coal gasifier ash with fly ash and bottom ash from a coal-fired power plant using lignite from the Dobro Solo mine. Results obtained indicate that levels of Sb, As, Be, Cr, Cu, Pb, Mo, Ni and Zn in gasifier ash leachate were similar to those in fly ash leachate. Barium levels in gasifier ash leachate averaged 2.7 times that in fly ash and selenium levels averaged 0.33 times. The average ratio for the total set was 0.99. The set average, relative to bottom ash, was 2.1 with the nickel ratio (R_{Ni = 0.31}) differing significantly from the average. Metal oxides, CaO, MgO, Na₂O, K₂O and MgO, in the Kosovo gasifier ash were found at levels similar to those in Kosovo fly ash, and except for K₂O, were approximately twice those in bottom ash. Concentration levels of all components showed relatively small variations averaging 50% of their mean annual concentration over the test period.     

典型高灰熔融性煤焦水蒸气气化特性研究

为解决我国高灰熔融性煤的利用难题,采用等温热重法,研究了典型贵州高灰熔融性煤焦在不同气化温度及不同水蒸气含量下的气化特性,并采用混合反应模型对试验数据进行处理,求取动力学参数。结果表明,在不同水蒸气含量下,随着气化反应温度的升高,典型贵州煤焦的反应性提高,气化反应速率的峰值增大,气化反应时间缩短;气化剂中水蒸气含量越多,煤焦反应性越好,气化反应速率的峰值越大,但当水蒸气含量大于30%后差别不明显;典型贵州煤焦与水蒸气反应的反应级数为0.912 9~1.620 9,活化能为149.34~165.12 k J/mol。     

原煤可选性评定新方法——特定数量效率法

分析了现行几种煤炭可选性评定方法的适用范围及其局限性 ;提出采用特定条件下的数量效率作为煤炭可选性的评定方法。该方法可以克服现行评定标准存在的各种问题 ,适用于所有原煤在任何分选密度下的可选性评定 ,科学而简便 ,并且不会出现偏差。     

Production of glass from coal fly ash

The coal fly ash from a Chinese thermal power plant was vitrified after the addition of ∼10 wt% Na₂O. The glass products have suitable viscosity at 1200 °C and displayed a good chemical durability. The heavy metals of Pb, Zn, Cr and Mn were successfully immobilized into the glass as determined by the toxicity characteristic leaching procedure method. Results indicate an interesting potential for the coal fly ash recycling to produce useful materials.     

Study on the washability of the Kaitai coal, Guizhou Province China

Tonnage of coal samples were collected from Kaitai Coal field, Puan County, Guizhou Province and sieved into different particle size catalogs. The analysis of the overall coal suggested that the coal has low ash but high sulfur content of 3.17 wt.% with medium to high volatile content. The heating value of the coal is 31.668 mJ/kg.The coal sample with different particle size ranges were tested for float-sink using gravity separation method, in which ZnCl₂ solutions with different density are used. It is showed that decreasing sulfur to 2.12 wt.% can give coal yield of 94.55%, suggesting that the coal's floatability is good with sulfur. The coal yield is only 85.4% when reducing sulfur to 1.5 wt.%, and 76.7% when sulfur is decreased to 1.2% through the ZnCl₂ float-sink process. The δ ± 0.1 is 20.55, which is in the 20.1-30 range, suggest that Kaitai coal is difficult to float-sink for depyritisation.Characterization of the floated coal at different sizes showed that the organic sulfur may mainly be present in the small size, the pyrite sulfur is mainly present in the coal with bigger particle size, which can be easily removed through float-sink process. The ash in the small particle sized coal is mainly from kaolinite and quartz, while the pyrite is the main ash contributor to the coal with big size.     

Uranium recovery from coal ash dumps of Mongolia

The concentration of natural radionuclides and the feasibility of recovery of uranium from browncoal ash of a Mongolian cogeneration plant were investigated. The concentrations of the elements were determined by instrumental gamma-activation (IGAA) and X-ray fluorescence (XRF) analysis. Uranium from brown-coal ash was leached with an 8 M HNO₃ + HF (10%) mixture. The extraction of uranium from the solution and its purification for the removal of accompanying elements were carried out on an anion exchanger. An ash sample after leaching contains neither natural radioactive elements (²³⁸U and ²³²Th) nor their decay products, thereby allowing for the use of the ash as a building material.     

Hydrothermal synthesis of zeolites from coal fly ash

The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were synthesised from the fly ash: analcime, faujasite (zeolite X) and gismondine (zeolite P). It was shown that the experimental conditions (temperature, reaction time and alkali concentration) have a significant influence on the type of zeolite and its content in the reaction products. The series of experiments resulted in building approximate crystallisation field of zeolites and other phases as the first stage of the formation of ceramic membrane and other materials.     

Production of ceramics from coal furnace bottom ash

Furnace bottom ash (FBA) is generated in significant quantities from coal fired power stations and is a problem when commercially viable reuse applications do not exist locally. Representative samples of FBA from the Kilroot power station in Northern Ireland have been milled, pressed and sintered at a range of temperatures to form new ceramic materials. The effect of adding recycled glass to the mix has been investigated. The optimum FBA ceramics were produced by sintering at 960 °C and these had a density of 2.388 g/cm³, zero water adsorption indicating minimal open porosity, and a Vickers hardness comparable to commercially available glass-ceramics. The addition of 20% by weight of glass reduced shrinkage during sintering, while the samples maintained high density and hardness. This glass addition allows greater dimensional control during sintering to form FBA ceramic tiles. The research demonstrates that FBA can be processed into ceramics for use in higher value products compared to conventional use as lightweight aggregate. Further research is required to optimize processing and fully characterize material properties. This novel approach to managing FBA has potential to transform a problematic waste in Northern Ireland into a valuable resource.     

利用MATLAB制作煤炭可选性曲线的图形用户界面

介绍了利用MATLAB语言绘制煤炭可选性曲线的程序原代码,该程序实现了友好的图形用户界面,并可以按不同指标查取其他指标,精确度高,应用方便。     

煤泥重介质旋流器在高硫难选煤分选工艺中的应用

介绍了小直径重介质旋流器在南桐高硫难选煤分选工艺中的实际应用,通过定量分析,总结了煤泥重介质旋流器在降灰、脱硫和减少煤泥浮选入料量方面的重要作用。     

Preparation of zeolitic adsorbents from waste coal fly ash

Power plants burning coal generate a large amount of fly ash as waste matter. The objective of this study is to produce zeolitic adsorbents that possesses high adsorptive capacity for toxic cations. The sample was first pretreated with a High Intensity Magnetic Separator for the removal of iron and magnetic materials (mainly Fe₂O₃ and TiO₂). The zeolitic adsorbents were prepared under the various conditions of NaOH concentration (1–5 N), reaction time from 3 to 96 hours and at the various temperatures of 60, 80 and 100°C. The results of the experiment showed that the coal fly ash should be synthesized with 4 N NaOH for 48 hours at 100°C in order to have good adsorptive capacity. The zeolitic adsorbents showed higher cation exchange capacity values than the natural zeolite in removing NH ₄ ⁺ , Pb²⁺, Ca²⁺and Cd²⁺ions.     

火力发电厂燃煤飞灰润湿性能

化学团聚是控制燃煤电厂细微颗粒排放最有效的方法之一。颗粒物被团聚剂润湿是化学团聚的首要步骤。以小龙潭电厂燃煤飞灰为对象,采用激光粒度仪研究了燃煤飞灰在十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(SDBS)和Triton X 100(TX100)三种润湿剂溶液中的润湿性能,考察了润湿剂浓度、温度对燃煤飞灰润湿性能的影响。结果表明：水仅能将飞灰颗粒中的PM^₁₀+部分全部润湿,0.25%的SDS溶液中PM_2.5⁺可全部润湿,1%的SDS及0.4%的SDBS溶液中PM₁⁺可全部润湿;TX100溶液在低浓度条件下具有较强的润湿飞灰颗粒的能力,且0.1%的TX100溶液对细微颗粒的润湿性能较好;温度从20℃上升到60℃,润湿剂溶液表面张力降低,飞灰的润湿性能增强。鉴于飞灰在三种润湿剂中良好的润湿性能,三种润湿剂均可作为团聚剂组分以促进燃煤飞灰中的细微颗粒润湿进而被团聚成为容易脱除的大颗粒。     

GB/T16417-2011《煤炭可选性评定方法》编制说明

国家标准GB／T16417--19964煤炭可选性评定方法》自1997年实施至2009年已经执行14a,随着行业技术进步及标准化技术的发展,原标准已有许多方面不适应发展的需要,同时在结构、格式方面,也不符合GB／T1．1-2009的要求。概括介绍了国家标准GB／T16417-2011《煤炭可选性评定方法》,阐述了修订该标准的必要性和意义,并对标准主要内容进行了说明。     

二酰异羟肟酸萃取法从粉煤灰中提取锗

利用二酰异羟肟酸 (DHYA)的磺化煤油溶液从低酸度粉煤灰浸取液中提取锗。采用相比 1 3～ 1 4 ,水相pH值为1 0 0～ 1 2 5,在室温下进行三级逆流萃取 ,使用NH4 F溶液反萃取 ,最后锗收率可达 99% ,产品纯度在 99 8%以上。     

Retention of sulphur by laboratory-prepared ash from low-rank coal

A procedure similar to that of Knudsen and Holm⁷ was applied to 195 measurements of ash from high sulphur subbituminous and lignite coals from New Zealand. Sulphur reaction by coal ash was not catalysed by iron oxide and no effect of MgO, Na₂, K₂O or CaO was observed.     

从粉煤灰中制备聚硅酸铝铁絮凝剂及应用研究

以粉煤灰、废钢渣为原料制备了高效絮凝剂———聚硅酸铝铁,确定了制备PAC的最佳反应条件,并对其进行了处理废水实验。结果表明,由粉煤灰为原料制得的产品聚硅酸铝铁(PAFSi)比聚合硫酸铁(PFS)处理废水效果更佳。     

A spectroscopic investigation of the banding or lithotypes occurring in Victorian brown coal seams

Solid-state ¹³C n.m.r. and infrared spectroscopy were used to investigate the gross differences in chemical structural between the five primary lithotypes or coal bands present in Victorian brown coal seams. Examination of a series of coal lithotypes, along with their insoluble kerogen fractions, indicated significant structural variation between the light and dark samples, particularly in their aromaticities and levels of lignin-derived structures. Comparison of K₂₉₂₀ (cm mg⁻¹) and K₁₇₁₀ (cm mg⁻¹) infrared data revealed that the aliphatic C-H content did not exhibit the level of lithotype dependence shown by carbonyl/carboxyl concentration. Correlation with ¹³C n.m.r. data revealed a direct inverse relation between aromaticity and carbonyl/carboxyl content. Aromaticity and carbonyl/carboxyl content are suggested to be the main gross chemical structural properties affecting lithotype classification. Investigation of a depth profile of the light lithotype revealed that gross structural variation between the samples did not result from rank effects. Rather, the depth profile reflects minor depositional variations which did not affect their lithotype classification. The gross chemical characterization of the lithotypes supports paleobotanical interpretation regarding the different depositional environments and inputs responsible for the observed coal banding.     

Studies of the fusibility of coal ash

To establish a means for predicting the melting temperature of coal ash, the chemical composition, mineral matter content and melting temperature were investigated for 24 coal ash samples. The fusibility of coal ash was studied from the view point of the mineral matter. The melting temperatures of these samples ranged from 1285 to > 1500 °C. A conventional acid-base index did not show a good correlation with melting temperature for these coal ash samples (correlation coefficient = −0.67) and the reason for this is discussed. An empirical index, which is derived from the correlation between mineral composition and melting temperature, is proposed. It was linearly proportional to melting temperature for the coal ash samples (correlation coefficient = 0.85) and furthermore, the applicability of the index to abitrary coal ash was demonstrated.