乳化柴油捕收剂的浮选试验研究

利用由柴油、表面活性剂和水以27:3:70的比例复合而成的新型乳化浮选药剂ZFC-1,对淮北瘦煤和张家口1/3焦煤2种煤样进行了浮选试验研究.结果表明,该浮选药剂性能优良,稳定性好,选择性高,改善了浮选性能,在基本保持精煤灰分不变的情况下,与柴油相比,使用ZFC一1作为捕收剂时,可提高精煤产率5%～22%,提高可燃体产率6%～23%,节约柴油或煤油用量70%.     

乳化煤油捕收剂的浮选效果

利用一种新型复合乳化剂将煤油乳化后作为捕收剂的浮选试验结果表明 ,这种乳化剂是一种良好的浮选助剂 ,用其乳化煤油不仅稳定性好 ,大大降低浮选油耗 ,而且显著改善煤泥的浮选效果。     

超声乳化柴油捕收剂制备及应用

入选煤泥组成日益复杂,浮选难度增大,传统烃类捕收剂逐渐成为制约浮选发展的瓶颈。采用超声乳化方法,综合考虑乳化剂的HLB、乳化剂用量、油水比、正丁醇加入量和超声时间等因素对乳化柴油稳定性影响,使用制备药剂进行了小浮选实验,发现乳化柴油捕收剂对河南,江苏和山东三地煤所得精煤回收率与相同剂量的柴油基本相同,所得精煤灰分较柴油低。研究表明,乳化柴油浮选选择性好,含油量为柴油的30%,成本为柴油的40%,经济效益明显。     

影响超声乳化柴油捕收剂稳定性的试验研究

针对目前传统煤泥浮选药剂价格高、用量大、难分散、选择性差等问题,采用超声方法制备了乳化柴油捕收剂,研究了亲水亲油平衡值(HLB)、乳化剂用量、油水质量比、助乳化剂、超声时间等因素对乳化柴油稳定性的影响,并利用浮选试验验证了乳化柴油的浮选性能.稳定性试验结果表明最优单因素条件如下:亲水亲油平衡值为13,复配乳化剂中失水山...     

白钨矿浮选731捕收剂低温乳化试验研究

介绍了731捕收剂在低温条件下试验的情况。试验研究结果表明，采用A和B药剂以5：6的比例混合组成的复合乳化剂对731进行乳化，低温时乳化体系稳定性好，浮选过程中降低乳化731的用量，同时提高了选择性，降低了浮选成本，实现了低温环境下白钨矿正常浮选作业，达到选矿技术攻关指标。     

利用非离子型表面活性剂乳化捕收剂对粗粒煤浮选的影响

由于乳化剂能减小油——水界面张力并降低捕收剂扩散至煤表面所需要的能量,因此可提高粗粒煤浮选的产率。乳化剂浓度是最大限度提高浮选产率的关键因素。     

煤用乳化捕收剂的浮选效果

在煤的浮选中,将捕收剂乳化后使用,可提高药剂分散性,促进药剂在矿浆中的扩散,提高药剂利用率.该文从乳化药剂油水配比、浮选速度及药剂选择性等方面,对山东某选煤厂浮选原矿进行了全面的试验.实验表明:乳化捕收剂具有较高的药效,可有效降低药耗,提高精煤质量,具有显著的经济效益及社会效益.     

水包油型乳化柴油制备及其对辉钼矿浮选的强化

柴油是浮选辉钼矿的常用捕收剂,但在矿浆中分散性差,影响其捕收效果。采用超声法制备水包油型乳化柴油,油水质量比为1∶10,以聚氧乙烯月桂醚为乳化剂,乳化剂用量为油、水总质量的1.5%,超声功率为300 W,超声时间为2 min。制备的乳化柴油用于辉钼矿粗选,可得到Mo品位和回收率分别为7.71%、86.72%的钼精矿,相较原柴油精矿Mo品位提高0.19个百分点,Mo回收率提高3.44个百分点。超声乳化提高了柴油在矿浆中的分散性,乳化剂的添加则保证了乳化柴油的稳定性,从而有效提高了辉钼矿浮选指标。     

乳化浮选药剂处理孙村细粒煤的试验研究

将捕收剂乳化后可有效提高其在矿浆中的分散性,降低捕收剂消耗。对孙村选煤厂细粒煤泥浮选的试验表明,将捕收剂乳化后使用,可以节省60%以上的浮选药剂,同时可提高浮精产率2~5个百分点,具有显著的经济效益及社会效益。     

乳化捕收剂强化煤泥浮选研究进展

与传统药剂(烃类油)相比,乳化捕收剂能降低油水界面张力,在水中的分散度高,可快速有选择性地吸附在煤表面,改善煤表面的疏水性,提高浮选效率,能够有效解决捕收性能差、选择性差和油耗高的问题.介绍了乳化捕收剂(普通乳状液和微乳液)的结构及形成机理,分析了机械搅拌、超声乳化和射流乳化三种制备乳化捕收剂的方法及优缺点,阐述了乳化捕收剂的分散度、表面改性作用及浮选速度与煤泥浮选效率提高之间的关系,总结了现阶段乳化捕收剂的研究类型及应用情况.提出针对煤泥的性质,设计及制备不同特性的乳化捕收剂,将有利于推动工业规模上煤泥的高效回收.     

不同因素对煤泥浮选指标的影响研究

以延安市禾草沟一矿5~#原煤浮沉得到的低密度精煤和高密度泥质页岩为原料,制备出匀质精煤泥和高灰细泥的复配煤样,在适宜的药剂条件下,通过正交试验,研究了浮选入料灰分、矿浆浓度、搅拌转速以及充气量四个因素对浮选精煤高灰细泥夹带、可燃体回收率、浮选完善指标的影响。结果表明:搅拌转速和充气量对三个指标的影响均不显著;矿浆浓度对精煤高灰细泥夹带量和浮选完善指标影响显著;浮选入料灰分对于可燃体回收率和浮选完善指标影响显著。     

高剪切调浆和捕收剂乳化处理对煤泥浮选效果的影响研究

为了考察高剪切调浆和捕收剂乳化处理对煤泥浮选效果的影响,以山西汾西矿业集团水峪煤矿有限责任公司选煤厂的浮选入料为对象,对比分析了柴油、柴油+调浆、乳化柴油及乳化柴油+调浆对煤泥浮选效果的影响规律。试验结果表明:高剪切调浆和柴油乳化处理均对提高煤泥浮选效果和节省柴油用量有积极作用,在同等灰分指标要求下,与采用柴油作为捕收剂相比,高剪切调浆和柴油乳化处理下的精煤可燃体回收率分别提高3.78和1.95个百分点,柴油用量由325 g/t分别降至225 g/t和100 g/t。两种处理方法均能促进非极性烃类油的分散,有利于降低柴油用量,同时提高煤泥浮选指标。     

抑制剂对屯兰选煤厂细煤泥浮选效果的影响研究

针对屯兰选煤厂细煤泥浮选效率低、生产成本高等问题,分别以煤油和仲辛醇作为捕收剂、起泡剂,探索水玻璃和三偏磷酸钠、羧甲基纤维素钠三种抑制剂对细煤泥浮选效果的影响规律,并确定不同药剂的最佳用量。试验结果表明:在试验范围内,随着抑制剂用量的增加,细煤泥浮选效果逐步改善,但过量添加抑制剂会使其浮选效果变差;当羧甲基纤维素钠用量为40 g/t时,细煤泥浮选效果最好,浮选精煤产率为69.72%,对应的灰分为9.81%,精煤可燃体回收率为78.60%,浮选完善指标为44.40%。     

循环水浓度对浮选指标影响的定量研究

采用不同浓度的模拟循环水作为两个选煤厂浮选入料稀释水,进行了系列单元浮选试验,通过线性规划计算,获得了可靠性良好的循环水浓度与浮选各项指标的回归方程,从而对循环水浓度与浮选指标的关系做出了准确的定量描述。     

Numerical and experimental study of the effect of a froth baffle on flotation cell performance

In this work, the effect of a froth baffle on flotation performance is investigated both experimentally and numerically. Flotation experiments with an artificial ore comprised of 80% silica as gangue and 20% limestone as floatable component were carried out to compare the flotation performance of a baffled froth system against an un-baffled froth system. The effect of the baffle’s inclination angle to the horizontal was also studied. Results indicated that a froth baffle has a profound effect on both recovery and grade. The presence of a froth baffle resulted in an increase in grade at the expense of recovery. The decrease in limestone recovery with the introduction of a froth baffle was found to be a function of the baffle’s inclination angle i.e. recovery decreased as the inclination angle becomes more acute. Water recovery as well as entrainment recovery herein represented by silica recovery decreased with decrease in baffle’s inclination angle. Numerical techniques were employed to model the experimental results. The 2D stream function equation/Laplace equation which is known to be adequate in describing froth transport was solved subject to boundary conditions that represent the presence of baffles. A solution was developed using finite difference methods on a rectangular map obtained using Schwarz–Christoffel (SC) mapping. Results from the simulations indicated a change in particle residence time distribution in a manner that reduces spread. The changes in residence time distribution helped in developing an explanation of the experimental data.     

柴油对浮选泡沫稳定性影响的试验研究

泡沫稳定性是影响浮选过程效率的重要参数之一。为了探究柴油对浮选泡沫稳定性的影响,借助泡沫扫描分析仪(FOAMSCAN)研究了气液两相体系下不同浓度的柴油与体积分数20×10-6的甲基异丁基甲醇(MIBC)混合溶液的起泡能力与泡沫稳定性,采用动态液膜分析装置分析了泡沫间液膜的最终状态,进一步明晰了柴油对泡沫稳定性的影响机制,并通过细粒煤浮选及气液固三相泡沫稳定性试验探讨了柴油对实际浮选体系泡沫性质及浮选效果的影响。气液两相体系泡沫稳定性试验表明,随着柴油浓度的增加,溶液起泡能力和泡沫稳定性逐渐降低。泡沫间液膜测试结果说明,柴油浓度加大使得泡沫间液膜由最终的平衡状态转为破裂状态,液膜稳定性变差,气泡更容易兼并甚至破裂,该结论与气液两相泡沫稳定性试验结果保持一致。浮选结果表明,柴油用量较低时,随着柴油浓度增加,最大泡沫层高度和半衰期逐渐增大,浮选精煤产率也随之增大,这主要是由于柴油改善煤样表面疏水性以及细粒煤的稳泡作用所致;但当柴油用量增加到一定浓度后,最大泡沫层高度和泡沫半衰期减小,浮选精煤产率减小,一方面,柴油油滴进入泡沫间液膜中,在范德华力等力的驱使下,泡沫间的液膜逐渐薄化直至形成经典的油滴架桥现象,最终导致气泡兼并甚至破裂,另一方面,柴油油滴竞争吸附起泡剂分子,使得气液界面的起泡剂浓度降低,从而导致泡沫稳定性降低,柴油具有一定的消泡作用。     

The entrainment effect on the performance of iron ore reverse flotation

An iron ore mineral processing plant in Brazil treating Itabirite ore was assessed by sampling a circuit consisting of Wemco 144 mechanical cells, as part of the AMIRA P9P collaborative research project. This paper presents and discusses the results of entrainability, water recovery and quartz and hematite grades associated to hydrodynamic parameters. The results indicated strong correlation between water recovery and hematite losses which was intensified by the operating conditions of the circuit.A potential alternative to reduce the hematite losses through entrainment and to increase quartz removal was to modify the traditional circuit design to treat rougher and cleaner/recleaner tails in different stages. In addition, the scavenger residence time must be matched to the quartz floatability. Changes to design and operation of these circuits are needed to sustain concentrate recovery and grade as iron ores become finer.     

The effect of reagent addition strategy on the performance of coal flotation

The recovery and grade of concentrates obtained by flotation is partly dependent upon froth structure. The flotation froth structure can be modified, and hence the flotation performance modified, by the addition of reagents.A direct control system was developed which permitted pre-determined addition profiles of reagent and water to be added to a cell. A series of experiments were performed using different strategies of reagent (Triton x-405) addition for the flotation of Bickershaw coal.A transputer enhanced Micro-Vax Computer was employed to grab images of flotation froths and to process them quantitatively in a parallel procedure. Using image processing techniques characterization of froth structures was achieved. The image processing procedures that were intended to run on-line, were examined and developed using video tapes of experimental runs, off-line.An essential stage in the development of such a system is the understanding of the adsorption behaviour of the reagent in terms of the kinetics, the distribution of reagent between the solid and solution phases, and the resulting effect on the froth structure. A kinetic model was developed to describe the adsorption of the reagent on the particles. The experimental recoveries and froth structure were investigated in terms of reagent distribution and the froth structure.     

浅谈影响选煤厂煤泥浮选效果的几个关键因素

浮选是目前细粒煤分选最有效的方法之一,是选煤厂工艺流程的重要环节,通过讨论浮选过程中的矿浆浓度、矿浆pH值、颗粒粒度、药剂制度、浮选设备选择、充气量、气泡尺寸、浮选动力学、气泡成型理论等主要因素对浮选效果造成的影响规律进行研究,为选煤厂浮选工艺相关参数的选择和优化提供借鉴。     

铝土矿反浮选脱硅技术研究

以河南某地中等铝硅比矿石为研究对象,围绕着铝土矿反浮选脱硅技术展开系统研究,研发专有分散剂BK500、选择性抑制剂BK501、含铝硅酸盐高效捕收剂BK421。试验采用两次脱泥、脱泥底流反浮选脱硅,最终获得Al2O3回收率为81.20%、铝硅比为10.82的合格精矿。