风化煤反浮选可行性试验

针对风化煤中矿物质含量大的特点,本文采用等离子体灰化、XRD、SEM、TEM等手段对新疆风化煤进行了表征分析。结果表明:新疆风化煤中含有高岭石、石英及烧石膏(半水石膏)三种矿物质,他们赋存在煤表面,相互连生,形成连生体,最终导致煤的疏水性变差,可浮性变弱。酸处理后煤样、高岭石、石英和烧石膏人工配样反浮选试验结果表明,人工配样精煤灰分(17.38%)明显小于风化煤精煤灰分(21.79%)。     

天宝红沙梁煤矿风化煤腐植酸提取工艺研究

以天宝红沙梁煤矿风化煤为原料并从中提取腐植酸,详细分析了影响萃取率的主要因素,用以确定最佳工艺参数。以腐植酸萃取率为指标,考察了提取剂种类、浓度、浸泡时间、固液比等因素对腐植酸萃取率的影响。研究结果表明,从风化煤中提取游离腐植酸时,选用稀HCl和NaOH效果较好,且当稀HCl浓度为1.70 mol/L、NaOH浓度为1.12 mol/L、稀HCl浸泡时间约4 h、NaOH浸泡时间约11 h、风化煤与稀HCl固液比为2∶25时,为天宝红沙梁煤矿风化煤提取腐植酸的最佳条件。     

我国泥炭、褐煤和风化煤的资源优势及其应用领域

介绍了腐植酸类资源的现状，阐述了我国在这方面的资源优势，并分别介绍了泥炭、腐植酸类资源在各领域的应用，最后对所存在的问题提出了相关建议。     

超声波处理改善风化煤泥浮选效果研究

煤泥浮选是湿法选煤厂中广泛存在的一种分选工艺,而风化煤泥浮选效果差已经成为选煤厂的一项重要难题。本文以超声波辐照为辅助手段研究风化煤泥浮选效果优化方案,并得到以下结论:先添加捕收剂再进行超声波辐照对浮选效果的改善程度最大,超声波辐照时间为40min时,浮选效果最佳,可燃体回收率为81.1%。改变起泡剂添加与超声波辐照的顺序对浮选效果没有明显影响。     

浮选尾煤再选试验研究

以钱家营选煤厂浮选尾煤为对象,进行再选试验研究。对煤样进行粒度分析,发现高灰细泥含量很高,决定采用反浮选预先脱泥,并探索了药剂用量对反浮选效果的影响;脱泥后的产品进行磨矿再选,工艺流程为:"反浮选─磨矿─再选"流程,最终得到了灰分为13.96%,产率为25.96%的精煤,采用该流程处理浮选尾煤可提高选煤厂经济效益。     

药剂C-1对氧化煤浮选的促进机理研究

针对氧化煤浮选效率低难以回收利用的问题,研制了一种新型捕收剂C-1。首先,将表面活性剂(酯类表面活性剂、Span80)和单馏程非极性烃类油按不同比例混合,通过浮选试验结果确定最佳质量比为5%。然后,将C-1应用于氧化煤浮选试验,对比其与传统药剂的浮选效果,得到最佳药剂使用量,利用红外光谱和润湿热测量等手段研究了C-1对氧化煤浮选的促进机理。结果表明,C-1通过化学吸附与氧化煤表面的含氧官能团结合,提高煤粒表面疏水性,使煤粒与气泡结合更稳定,从而提高精煤产率、可燃体回收率及浮选完善指标。当C-1用量1200g/t,仲辛醇用量150g/t时,精煤产率为 64.51%,精煤灰分最低为 11.96%,浮选完善指标为 37.87%,此时氧化煤的浮选效果最佳。     

复合药剂在风化煤泥浮选中的性能研究

针对风化煤难浮选的问题,制备了一种将捕收剂、起泡剂、活化剂及调整剂合为一体的复合药剂,对其主要官能团进行了红外光谱分析,并重点考察了复合药剂中活化剂的用量与调整剂的加入对浮选效果的影响,分析了矿浆浓度对浮选效果的影响。结果表明,该复合药剂改善了风化煤泥的浮选效果,与使用传统浮选药剂相比,浮选完善度得到了很大提高;在矿浆浓度为80g/L时,浮选完善度达到最大,与传统药剂相比,提高了15.207个百分点。     

浅谈容量法测定煤中总腐植酸

掌握腐植酸的性质、反应原理及在测定中的影响因素,从而准确测定腐植酸的含量。     

Dynamic froth stability in froth flotation

A new measure for froth stability is introduced in this work, based on a dynamic stability test for non-overflowing froth columns. The dynamic stability factor represents the lifetime of a bubble in the froth, and is defined as the ratio of the total volume of froth at equilibrium to the volumetric gas rate introduced into the system. Experiments have been carried out at laboratory scale to measure the dynamic stability factor under different operating conditions. Air flowrate and frother concentration were the key operating variables. It was found that the equilibrium height and the dynamic stability factor depend significantly upon both the air flowrate and the frother concentration. Also, the dynamic stability factor and the fraction of air overflowing as unbroken bubbles in batch flotation tests were related and can be used to establish a stability criteria. These measurements will also allow a clearer quantitative link to be formed between froth stability with froth structure and flotation performance.     

Influence of coal particles on froth stability and flotation performance

Solid particles have significant effect on flotation froth. In this research, the effects of coal particles of different size and hydrophobicity on froth stability and flotation performance were studied. The froth stability was measured in both the froth formation and froth decay processes by maximum froth height, froth half-life time and water recovery. The results show that fine particles of moderate hydrophobicity contributed most to maximum froth height in the froth formation process and were most favorable for flotation. Fine hydrophilic particles stabilized the froth in the froth formation process but the froth half-life time was very short due to the high water solid ratio. High hydrophobic particles of both fine and coarse size fractions greatly increased the froth half-life time in the froth decay process. But the froths were very rigid and the maximum froth heights were very low. The presence of fine hydrophobic particles was very unfavorable for the recovery of coarse particles.     

煤泥浮选泡沫图像分割与特征提取

针对在煤泥浮选泡沫图像中的煤泥气泡互相粘连、边界模糊的情况,根据分水岭变换模拟浸水原理,提出一种新的、有效的分割算法,同时应用数学形态学中的腐蚀和膨胀算法,解决了经典分水岭算法不能处理的过分割和欠分割问题,使得粘连的煤泥气泡得到了有效的分割.然后计算出各个煤泥气泡的横截面积、周长、形状等物理特征参数,这些参数是实现自动控制浮选过程的重要依据.     

磁化浮选脱硫初探

为了降低煤炭中的硫分、提高煤炭资源的利用率 ,经过实验室试验 ,用磁化浮选的方法脱除 0 5mm以下细粒煤中的硫分。通过试验表明在一定的磁场强度下或含有一定磁场强度的磁化水中用浮选机对 0 5mm以下的细粒高硫煤进行浮选 ,可以达到一定的脱硫效果     

煤泥浮选泡沫图像灰度行程及其统计纹理特征

针对煤泥浮选泡沫灰度图像统计纹理特征问题,通过实验室浮选柱试验,采集了大量的煤泥浮选泡沫图像,分析了泡沫图像的类别及特征,提出了描述浮选泡沫纹理特征的灰度行程矩阵提取算法,并进一步提取灰度行程矩阵的行程因子特征参数来描述浮选泡沫的视觉纹理特征,分析了各特征参数随浮选时间的变化关系.研究表明,泡沫灰度行程因子特征参数能够表征浮选泡沫图像纹理特征,并与特定的泡沫状态相关,可为煤泥浮选视觉监控系统提供泡沫状态信息.     

无机盐阳离子对粉煤灰浮选泡沫稳定性的影响研究

粉煤灰中矿物组成的自然属性使得浮选脱炭体系的泡沫稳定性较差,从而影响了未燃炭的有效脱除。通过添加无机盐阳离子的方式来改变粉煤灰浮选矿浆体系的液相性质,研究了不同离子种类和含量对两相泡沫和粉煤灰浮选三相泡沫稳定性的影响,并进行了浮选验证。研究结果表明：无机盐阳离子的添加提高了泡沫的稳定性,阳离子价态越高,这种稳定作用就越明显。利用泡沫稳定性调节中的离子效应,对采自湖北黄石的粉煤灰样品进行了浮选脱炭的验证试验,结果表明：Fe3+对泡沫的稳定作用有效提高了粉煤灰的浮选脱炭效果,与空白浮选体系相比,在Fe3+浓度为3 mmol/L的条件下,浮选低炭灰烧失量由8.85%降低至5.57%,炭脱除率由41.94%提升至74.55%;与添加Fe3+的浮选体系相比,Mg2+和Na+对浮选指标的提高作用依次减弱。     

Role of dixantogen in froth flotation

Mechanism of dixantogen action in froth flotation is discussed. It is shown that this reagent eliminates kinetic constraints during formation of a flotation complex, rather than improves hydrophobicity of a mineral surface.     

Correlation of air recovery with froth stability and separation efficiency in coal flotation

Recent research progress in hard rock mineral flotation shows that froth stability can be represented by air recovery, which is defined as the fraction of air entering a flotation cell that overflows the weir in unburst bubbles, and that air recovery has strong correlation with the separation performance of mineral flotation. Yet no experimental work on air recovery has been devoted to coal flotation. This paper studies air recovery in coal flotation and examines the links between air recovery, froth stability and coal flotation performance. A series of experiments were conducted using a laboratory-scale mechanical flotation cell at various methyl isobutyl carbinol (MIBC) concentrations and aeration rates. It was found that air recovery has a strong correlation with dynamic froth stability determined by measuring the maximum froth height in a non-overflowing froth column. At a fixed aeration rate (hydrodynamic condition) and various MIBC concentrations, a strong correlation between air recovery and coal flotation performance was also observed.