A STUDY OF THE FLOTATION OF OXIDIZED AHASRA COAL

ABSTRACT

The flotation of oxidized Amasra Coal which was collected between 1973–1978 and, stored in the atmospheric conditions was examined In this work. Coal samples were fractioned by wet screening to +0.560 mm, ?0.500 + 0.140 mm, ?0.140 mm particle sizes and first fraction was ground to ?0.560 mm before flotation. Motorin and pine oil which had been heated at 125° C for 5 hours were used ns flotation reagents. The influence of impeller speed, aeration rate, solid concent of the pulp, reagent amounts were examined and optimum values were determined. Increase of the pine oil amount added to the pulp, increased the coal. recovery on the flotation of this oxidized coal.     

THE INCREASE OF EFFICIENCY OP PINE OIL BY HEATING AND USAGE IN THE FLOTATION OF OXIDIZED AHASRA COAL

ABSTRACT

The effect of heating temperature and time on the efficiency of pine oil was examined in the flotation of oxidized Amasra Coal in this work. Samples were taken from waste heap Amasra Coal which were collected in 1973–1978 and stored in atmospheric conditions. The optimized impeller speed was 1000 rpm, aeration rate was 35 ml/s and solid content of the pulp was 20% in the flotation tests. Motorin was added to the pulp as a collector. The pine oil was heated to 50^°C, 75^°C, 106^°C, 125^°C, 150^°C, 175^°C, 200^°C and used as a frother. The flotation resulta indicated that 125^°C was suitable temperature for heating. Increasing the heating time increased the efficiency of pine oil. The recovery of combustibles also Increased depending on the increase in the amount of oil heated for 5 hours at 125^°C.     

THE INCREASE OF EFFICIENCY OP PINE OIL BY HEATING AND USAGE IN THE FLOTATION OF OXIDIZED AHASRA COAL

The effect of heating temperature and time on the efficiency of pine oil was examined in the flotation of oxidized Amasra Coal in this work. Samples were taken from waste heap Amasra Coal which were collected in 1973-1978 and stored in atmospheric conditions. The optimized impeller speed was 1000 rpm, aeration rate was 35 ml/s and solid content of the pulp was 20% in the flotation tests. Motorin was added to the pulp as a collector. The pine oil was heated to 50^°C, 75^°C, 106^°C, 125^°C, 150^°C, 175^°C, 200^°C and used as a frother. The flotation resulta indicated that 125^°C was suitable temperature for heating. Increasing the heating time increased the efficiency of pine oil. The recovery of combustibles also Increased depending on the increase in the amount of oil heated for 5 hours at 125^°C.     

氧化煤蜡制备车用乳液的研究

以高性能氧化煤蜡为原料制备车用乳液,针对乳化过程考察了不同配方以及工艺条件对制备车用乳液的影响。结果表明,车用乳液的最佳配方是:酸值(KOH)为27~29mg/g、皂化值(KOH)为75~80mg/g的氧化煤蜡用量4%,复合乳化剂用量5%~6%,稳定性助剂用量0.4%,上光性硅油含量50μg/g,挥发性溶剂用量1%,其余为去离子水。在搅拌速率900~1 050r/min,乳化温度85~90℃,乳化时间35~40min工艺条件下制备的O/W型车用乳液乳液平均粒径在0.1μm左右,对汽车表面涂膜影响等主要性质符合GB/T23437—2009指标要求。     

COAL FLOTATION IN THE PRESENCE OF HUMIC ACIDS

ABSTRACT

A high ash (38%) Illinois coal was studied. Up to 37% by weight coal flotation recovery was observed at a pH of 5.Even small amounts of humic acids (70 ppm) were observed to completely depress the flotation recovery of the coal. The humic acids also decreased the zeta potential of the coal and a naturally occur ring pyrite. The addition of O-ethyl xanthic acid enhanced the flotability of coal as well as mineral matter, the increase in flotability of coal being greater than that of pyrite at low dosages of xanthic acid, the heating value recovery ratic was observed fee increase with the xanthic acid amount added, up to 79% Btu recovery was obtained. The humic acids adsorption on coal was also investigated.     

ENRICHMENT OF GAS-FLAMING COAL BY THE AGGREGATIVE FLOTATION METHOD

Abstract

Aggregative flotation tests of gas-flaming coal were carried out in a laboratory flotation machine and a flotation column. Aggregation of coal feeds was carried out using as a collector unemulsified and emulsified kerosene at dosages of 130 and 10 kg/t, respectively. The results of the aggregative flotation showed that it is possible to beneficate gas-flaming coal at a huge dosage of the collector, the flotation response of which is very low. Preemulsification of kerosene caused a distinct decrease of its consumption. The efficiency of aggregative flotation of coal was higher in the flotation machine; however, the flotation selectivity of the finest feeds (?0.13 and ?0.23 mm) in the column was a little better. The influence of the size of coal grains on coal recovery and ash reduction both in the flotation machine and flotation column was interpreted as dependent on the decrease of the contact plane of aggregates formed by coal grains with air bubbles and on the size of these aggregates.     

ENRICHMENT OF GAS-FLAMING COAL BY THE AGGREGATIVE FLOTATION METHOD

Aggregative flotation tests of gas-flaming coal were carried out in a laboratory flotation machine and a flotation column. Aggregation of coal feeds was carried out using as a collector unemulsified and emulsified kerosene at dosages of 130 and 10 kg/t, respectively. The results of the aggregative flotation showed that it is possible to beneficate gas-flaming coal at a huge dosage of the collector, the flotation response of which is very low. Preemulsification of kerosene caused a distinct decrease of its consumption. The efficiency of aggregative flotation of coal was higher in the flotation machine; however, the flotation selectivity of the finest feeds (-0.13 and -0.23 mm) in the column was a little better. The influence of the size of coal grains on coal recovery and ash reduction both in the flotation machine and flotation column was interpreted as dependent on the decrease of the contact plane of aggregates formed by coal grains with air bubbles and on the size of these aggregates.     

油田含油污泥浮选分离研究

浮选是利用液—气—固或液—气—液界面分离不同物质的一种分离技术。作者采用国产叶轮机械搅拌式浮选机和国产药剂对江汉油田的含油污泥进行了叶轮浮选的试验研究,取得了油、水、泥良好分离与综合回收的结果。     

STUDY ON THE MICROEMULSION BEHAVIOR OF THE OXIDIZED PARAFFIN WAX

ABSTRACT

The interfacial tension between paraffin wax and water, as well as oxidized paraffin wax and water has been studied and the results showed that the interfacial tension between oxidized paraffin wax and water decreased obviously after paraffin wax was oxidized to proper degree. Meanwhile the pseudo-ternary phase diagram of the oxidized paraffin wax/surfactants/water system has been determined. It was confirmed that using a single surfactant A or cosurfactant B couldn't prepare oxidized paraffin wax microemulsion and the cosurfactant A/surfactant B mass ratio k _m has a proper range and an optimized value to produce the oxidized paraffin wax microemulsion, moreover, the microemulsion particle distribution was analyzed.     

STUDY ON THE MICROEMULSION BEHAVIOR OF THE OXIDIZED PARAFFIN WAX

The interfacial tension between paraffin wax and water, as well as oxidized paraffin wax and water has been studied and the results showed that the interfacial tension between oxidized paraffin wax and water decreased obviously after paraffin wax was oxidized to proper degree. Meanwhile the pseudo-ternary phase diagram of the oxidized paraffin wax/surfactants/water system has been determined. It was confirmed that using a single surfactant A or cosurfactant B couldn't prepare oxidized paraffin wax microemulsion and the cosurfactant A/surfactant B mass ratio k_m has a proper range and an optimized value to produce the oxidized paraffin wax microemulsion, moreover, the microemulsion particle distribution was analyzed.     

LOW TEMPERATURE ASHING: A METHOD TO ASSESS THE EFFECT OF ADDITIVES ON GRINDING AND FLOTATION OF COAL

ABSTRACT

In this paper an attempt has been made to study the effect of using chemical additives on grinding and flotation of thermal coal containing 40% ash. The mill products are analysed by the new technique of low temperature ashing (LT Ash). The LT ash characterisation are in excellent agreement with the results of sink float and flotation studies. Triethanolamine and Polyethylene glycol have shown many fold enhancement in fine grinding. However, Triethanol amine selectively grinds gangue in comparison to coal, while Polyethylene glycol enhances selective grinding of coat in comparison to gangue. This is supplemented by the results of flotation. There is an increase in recovery of combustibles from 39% in absence of additive, to 83% in Polyethylene glycol grinding. The flotation product contained ash between 22-25%.     

LOW TEMPERATURE ASHING: A METHOD TO ASSESS THE EFFECT OF ADDITIVES ON GRINDING AND FLOTATION OF COAL

In this paper an attempt has been made to study the effect of using chemical additives on grinding and flotation of thermal coal containing 40% ash. The mill products are analysed by the new technique of low temperature ashing (LT Ash). The LT ash characterisation are in excellent agreement with the results of sink float and flotation studies. Triethanolamine and Polyethylene glycol have shown many fold enhancement in fine grinding. However, Triethanol amine selectively grinds gangue in comparison to coal, while Polyethylene glycol enhances selective grinding of coat in comparison to gangue. This is supplemented by the results of flotation. There is an increase in recovery of combustibles from 39% in absence of additive, to 83% in Polyethylene glycol grinding. The flotation product contained ash between 22-25%.     

煤液化残渣加氢性能研究

 通过含大量沥青质（PAA）的煤液化残渣（CLR）在微型反应釜的加氢试验,考察了温度、气氛、氢初压以及反应时间对CLR中油（Oil）、沥青质（PAA）和四氢呋喃不溶有机质（THFIS）加氢性能的影响。结果表明,CLR中的重质组分—PAA和残余煤可进一步加氢转化成Oil,CLR–A、B中PAA最高转化率分别为77.43%和80.54%;氮气压力的存在能促进CLR中残余煤转化成PAA,高压氢有利于残余煤和PAA加氢转化成Oil。试验得出,在本实验范围内CLR-A、B的适宜加氢温度均为450℃,最佳氢初压均为6 MPa,最优反应时间分别为60min、40min。     

HP40合金试样氧化表面催化结焦

以石脑油为裂解原料,在850℃下进行了HP40合金试样氧化表面的催化结焦实验。采用扫描电子显微镜(SEM)、能量色散谱仪(EDS)和拉曼光谱表征了HP40合金试样的氧化层和结焦层。结果表明,HP40合金试样表面氧化层疏松、多孔,主要由(Cr, Fe)尖晶石和少量的Fe2O3组成。在结焦初始阶段,结焦速率较大,然而随着结焦实验时间的增加,结焦速率开始降低,最后趋于稳定值0.0084mg/(cm2.min)。在形核阶段,结焦层的粒子直径约为1μm,在催化结焦的后期,丝状焦直径约为0.2μm,当结焦机理为热裂解结焦时,丝状焦直径又增加到0.5μm。     

煤炭直接液化起始溶剂油的研究

针对神华集团有限责任公司在建的煤直接液化示范工程所需起始溶剂量大、煤炭焦化产溶剂不足的问题,在0.1 t/d小试装置(BSU)和6.0 t/d工艺开发装置(PDU)上对重油催化裂化回炼油芳烃抽提装置生产的重芳烃作为煤炭直接液化的起始溶剂进行考察.结果表明,重油催化裂化回炼油芳烃抽提装置生产的重芳烃经过多次加氢处理后,其密度和组成与煤液化自产溶剂类似,可以作为煤炭直接液化装置的起始溶剂.在PDU上使用该溶剂,当压力为17 MPa、反应温度为450 ℃左右时,煤转化率达90.42%,液化油收率为56.04%.     

改性焦油沥青粘层的配制和粘接性能研究

针对水泥混凝土＋沥青混凝土路面的层间粘接不良问题，研制了一种改性焦油沥青粘层，并对它的剪切强度、抗拉强度和水泥混凝土（钢板）—沥青混凝土层间粘接强度进行了测定。结果表明，采用改性焦油沥青粘层，可大幅度地提高层间粘接强度。     

煤的厌氧微生物降解研究

煤能否被厌氧微生物降解产气,是地学界长期争论的地质及方法技术问题.本文以生物气模拟试验为基础．对核问题进行了研究,证实了煤可以被厌氧微生物降解这一事实,同时文中探讨了煤的厌氧降解产气作用对煤层气勘探选区的意义.      

混合煤样最大热解峰温与镜质体反射率的研究

利用中国大陆地区两个高、低成熟度煤样,模拟再沉积物质来探讨其最大热解峰温(T_max)的变化与其镜质体反射率(R_o)的对应关系。对依比例混合后的混合样进行热解分析,再将量测两煤样的镜质体反射率的资料点,以相同的比例用随机取样的方式将其混合后取平均值,以对应其T_max的结果。实验结果显示:1)低成熟度煤样,在混有不同比例高成熟度煤样时,其T_max值将反应低成熟度之情形,即取含有再沉积的岩层样品,其T_max将呈现年轻地层的成熟度。2)对高成熟度的物质采样或进行热解分析的过程中,即便是在极微量的情况下,亦应避免受低成熟度物质的污染。3)随着低成熟度煤样配比的增加,T_max迅速下降,其与R_o的关系与Ⅲ型干酪根的线性对应呈现明显差异。      

煤在2种不同体系的生气能力研究

分别采用了封闭体系和半开放体系对同一煤样的生气能力进行了模拟。实验结果表明：在半 开放体系和封闭体系中，煤的生气过程有比较大的差别；煤在封闭体系中开始生气温度、生 气高峰对应的温度点都比半开放体系低；在同一温度点，煤在半开放体系生气量比封闭体系 少的一个原因是由于半开放体系中重烃气体和液态烃能及时排出，在高温阶段未裂解成甲烷 的缘故；压力可能对气体的生成有促进作用；生烃体系的开放(或封闭)程度对煤生气过程影 响非常大。     

我国南方煤化沥青与石煤的碳同位素研究

江南隆起一带下古生界煤化沥青的δ¹³C 值一般在-28‰左右,同上震旦统、下寒武统的石煤、炭质页岩相近,这说明它们之间有亲缘关系。下古生界煤化沥青δ¹³C 值比母质不同的河池煤化沥青轻约6‰,比腐殖煤轻7‰以上。