极细粒煤选择性双向絮凝脱硫降灰实验研究

介绍了选择性双向絮凝分选原理，根据该原理研究了极细粒煤泥深度脱硫降灰技术，分析了煤样粒度、非极性油与分散剂用量对选择性双向絮凝分选效果的影响，结果表明：使用该技术对极细粒煤泥分选后，可使其灰分降到1％以下，可燃体回收率达90％以上(最高值达94．57％)，产率达69．77％．脱硫时，可将硫分从3％降到0．4％以下，而且脱硫的同时可以脱灰。     

超声波处理对煤泥特性的影响研究

为了提高煤泥浮选的效率和选择性，提出了在浮选前对煤泥进行超声波预处理的方法．利用扫描电镜、激光粒度仪和图像识别软件等研究了超声处理对煤泥特性的影响．比较了超声波处理前后相同粒级煤泥的产率、硫分、灰分和圆形系数，分析了超声波处理前后煤泥颗粒的表面状态，并用真空浮选试验进行了验证．浮选速度试验结果表明，超声处理后精煤的硫分、灰分较超声波处理前分别降低了33．84％和32．09％，前2min的精煤产率平均提高了约10％．试验证明超声处理改变了煤泥颗粒的大小、形状以及煤粒表面的状态，促使煤粒与黄铁矿、矸石解离，因此超声波预处理是煤泥浮选脱硫降灰的一种有效方法．     

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.     

极细粒煤泥分选新方法：选择性絮凝

采用选择性絮凝剂,对煤中可燃体与非可燃体进行分离,称为选择性絮 凝。笔者对大屯、八一、大武口等5个选煤厂和煤矿的极细粒煤泥进行了大量的 试验,证明该法可作为极细粒煤泥的分选方法,并具有较好的选择性。经分选, 一般精煤灰分为12-13％,最低为5.73％,可燃体回收率达90％以上,两产品 之间灰分差一般在50％左右,效果较好。因此,是一种较有前途的方法,可用 在分级浮选中,作为极细粒煤泥的分选方法。     

Triboelectrostatic Separation-anEfficient Method of Producing Low Ash Clean Coal

1　 IntroductionActive carbon has been used in fields ofmedicine,food,environmental protection,mili-tary,and so on,because it has a developed innerspace and a tremendous specific surface area.Thepresent active carbon produced from coal is in itslow- grade because of the high ash contentof feed-stock coal.To deeply remove ash and producelow- ash ( <3% or <2 % ) clean coal is the keystep to produce high- grade coal- base active car-bon.At present,the wet processing is the mainmethod of fine coal…     

Performance analysis of jig for coal cleaning using 3D response surface methodology

Beneficiation of coal of -4.76 mm + 3 mm size fraction was investigated in a laboratory model Denver jig.Process variables were studied to analyze their effect on the performance of jig in terms of yield and ash content of clean coal. Three-factor three-level Box-Behnken design of experiments with response surface methodology(RSM) was employed to understand the performance behavior of jig. From the study, the bed height was found to be the most significant parameter affecting the yield and ash content of clean coal. It was possible to reduce the ash content from 24.32% in feed to an ash content of 16.55% in clean coal at 2 L/min water flow rate and 10 min jigging time. Influence of operating variables of the jig on responses was presented and discussed in 3D surface plots. The developed model was found to be significant within the range of parameters under investigation with correlation of co-efficient values as 0.99(yield) and 0.98(ash).     

细粒煤浮选数学模型的研究

通过大量试验,研究了浮选泡沫产品中细粒煤含量与水量关系,探讨了浮选过程中水流的机械夹带对细粒煤浮选的影响,考察了水浮选速率常数Ｋｗ 与操作变量之间的关系,得出了水浮选速率常数与操作变量之间的经验公式,确定了水量回收模型,从而最终建立了细粒煤产率与回收水量之间关系的动力学模型．通过引入降灰系数,导出了任一浮选时刻对应的细粒浮选精煤灰分的计算公式．     

Research on Mathematical Model of Fine Coal Flotation

通过大量试验,研究了浮选泡沫产品中细粒煤含量与水量关系,探讨了浮选过程中水流的机械夹带对细粒煤浮选的影响,考察了水浮选速率常数K     

Effects of clay and calcium ions on coal flotation

The microflotation of three single minerals, mixed coal–kaolinite and mixed coal–montmorillonite were examined to study the effects of clay and calcium ions on coal flotation. The results show that the ash content of flotation concentrate increases by 3% in the presence of clay minerals, and the ash content would further increase by 3% in co-presence of clay minerals and high concentration of Ca²⁺. Scanning electron microscope (SEM) images and elemental spectrum analysis indicate that fine clay particles that coat on the coal surface, which is called slime coating, can affect the coal flotation. The slime coating would be induced much more easily in the presence of Ca²⁺.     

应用摩擦电选技术降低微粉煤灰分

通过摩擦电选技术对原煤灰分约20％，粒度小于0.074mm，矿物质充分解离的微粉煤进行了干法分选试验，取得了精煤产率63.00％，灰分10．73％和尾煤产率36．80％，灰分32．98％的显著分选效果．试验表明：空气湿度增大后，精煤的产率有所下降，但通过增加极板的长度或提高电场强度，可保证精煤的产率，即摩擦电选过程对空气湿度变化的敏感性不大，主要决定于煤种的电选可选性；吸附在正、负极板上的颗粒主要集中在极板前段，说明物料摩擦带电充分，且正、负极板末端煤样的灰分相差不大，符合分选过程动力学规律。     

空气分级与空气重介流化床分选联合工艺研究

分析了固体颗粒在气-固流化床中的受力情况和运动方程，通过理论分析和实验得出了空气重介流化床分选入料的适宜粒级。讨论了空气重介流化床分选对入料粒度上下限的控制方法和存在问题，介绍了潮湿原煤空气分级新方法。试验表明，空气分级对潮湿原煤颗粒表面的煤粉有“清洗”作用，脱粉效果好，粗粒产物中含粉率仅为0.2%。这对控制入料粉量，稳定流化床密度和减少介质净化非常有利；空气分级还有分选作用，就试验煤种而言，其细粒级产物灰分比原煤中同粒级灰分降低1.7个百分点，比原煤灰分降低7.5个百分点，空气分级和空气重价流化床分选结合，可优化干法选煤工艺，降低工程投资和分选成本50%以上。     

An Entrapment Model of Water Flow on Fine Coal Flotation

Effect of entrapment of water flow on fine coal flotation was studied. The relation between constant of water flotation rate and flotation time was investigated and the water recycling model determined. The entrapment model of water flow about the relation between the recovery of fine particle and that of water in concentration was established. Finally, the equation about ash in fine clean coal at any time was derived by introducing a de-ashing coefficient.     

从高碳粉煤灰中浮选回收炭的试验研究

基于工艺矿物学原理,对某动力厂排放的高碳粉煤灰进行浮选回收炭的可选性试验. 结果表明,粉煤灰细度和浮选药剂用量是影响其浮选效率的重要因素. 经过“一粗一扫”的浮选流程,可得固定炭含量分别为58 .56 %和49 .20 %的精炭,总回收率达到89 .32 %,尾灰的固定炭含量降至5 .86 %;而经过浮选全流程试验后,可得固定炭含量为76 .93 %的精炭,总回收率为70 .17 %,尾灰固定炭含量为11 .89 %,且精炭和尾灰均可综合再利用.     

1000MW锅炉污泥掺烧温度场数值模拟

采用FLUENT软件对电站锅炉污泥掺烧温度场进行数值模拟分析。分别对污泥掺烧比例为0,1.3%,2.9%, 4.8%的煤燃烧情况下的温度场进行了比较。结果表明:随着污泥与煤粉掺烧比例的增加,污泥与煤粉的混合物中灰分含量增加,可燃物的含量减少,水分大幅增加导致炉膛中心温度出现明显的变化。     

新型抑制剂在铜铅浮选分离中的应用

用一种工业副产品为原料合成了多羟基硫代磷酸盐抑制剂．浮选试验表明其对方铅矿有较强的选择抑制作用,抑制效果优于重铬酸钾,是铜铅混合精矿浮选分离的一种比较理想的抑制剂．     

煤泥浮选测控系统的研究

浮选自动化在我国多年来俳徊不前,一直采用根据入浮煤浆中的干煤泥量来确定加药量的前馈控制方法,而不直接以产品的数质量指标作为控制目标,导致浮选生产效率较低。针对上述问题,研究了浮选工艺参数的检测方法,开发了浮选浆位仪和煤浆测灰仪,设计了浮选计算机控制系统,它根据煤浆测灰仪旁线检测的精煤灰分,运用模糊控制技术,通过调整浮选药剂添加量和浮选机浆位,来实现浮选过程的反馈控制,工业性试验表明,煤浆测灰仪的性能指标接近国外先进水平,煤泥浮选测控系统在淮北选煤厂的现场使用,使浮选生产在精煤灰分合格的前提下,得到了较高的产率,并降低了药剂用量,从而保证选煤厂高效率地运行。     

Parametric study of electrostatic separation of South African fine coal

The fact that water requirements are a major problem for present and future developments in material beneficiation, and the construction of a new power plant in South Africa, forms the basis for the utilization of a Rotary Triboelectrostatic Separator (RTS) for beneficiation of South African pulverized coal. The cleaning potential of Majuba and Koorfontein coal was first evaluated using kinetic froth flotation tests on the -177μm coal fraction. The RTS tests were conducted under varied process parameters. Parameters such as applied separating voltage, air injection velocity, particle feed rate and splitter position were investigated. Two stage separation results show that the RTS reduced Majuba coal initially containing about 30% ash to a clean product of 14.30%, or 19.46%, ash at a combustible recovery of 15.10%, or 53.02%, respectively. Similar separation performance was also achieved with the Koorfontein coal. The mineral and organic compositions in the feed, after single stage and after the second stage separations were characterized using X-ray diffraction analysis. The results show a better separation for the second stage coal products.     

神华配煤孔隙分形对燃烧特性的影响

利用氮气吸附仪、沉降炉、扫描电镜(SEM)和X-射线能谱仪(EDS)研究了动力配煤的孔隙分形结构对着火和燃烧特性的影响.对神华煤分别与准格尔煤和澳洲煤组成的配煤研究表明,配煤孔隙分形维数随单煤比例呈现出单调变化规律,并且与比表面积和比孔容积的变化规律基本一致.当神华配煤的分形维数由2.451增加到2.482和2.532时,着火温度由783 ℃降低到587 ℃和462 ℃,飞灰中碳的质量分数由3.62%减少到2.83%和1.83%,说明配煤的分形维数越大则越容易着火和燃尽.随着准格尔煤比例增加和神华煤比例减少,燃烧渣样中硅铝质量比减小且灰熔点提高,导致配煤的结渣程度明显减轻.     

Slagging characteristics of molten coal ash on silicon-aluminum combustion liners of boiler

In order to study the slagging characteristics of boiler combustion liners during pulverized coal stream combustion, the slag samples on the surface of combustion liner were investigated by X-ray diffractometry, scan electron microscopy and energy dispersive X-ray analysis, and the transformation characteristics of the compositions and crystal phases were studied. The results show that the size of slag granules decreases as the slagging temperature increases; the crystallinity of coal ash I reduces to about 48.6% when the temperature is increased up to 1 350 ℃, and that of the coal ash II reduces to about 65% when the temperature is increased up to 1 500 ℃; the encroachment of molten coal ash to the combustion liner is strengthened. At the same time, the diffusion and the segregation of the compositions in combustion liners have selectivity, which is in favor of enhancing the content of crystal phases, weakening the conglutination among molten slag compositions and combustion liner, and avoiding yielding big clinkers. But the diffusion of the compositions in combustion liners increases the porosity and decreases the mechanical intensity of combustion liner, and makes the slag encroachment to the liner become more serious.     

Research on Factors Affecting Flotation and Desulfurization of Coal by Electrochemical Method

Influence of factors such as potential of electrolyte, electrolyzing time, concentration of electrolyte, and pH value on flotation and desulfurization of coal was researched. The result shows that the electrochemical reduction can enhance the desulfurization effect and increase the yield of clean coal under certain conditions. So it is an effective method.