45m~3机械搅拌式浮选机的设计与应用

为实现浮选机的大型化、高效化、节能化,设计了45 m3机械搅拌式浮选机。阐述了45 m3机械搅拌式浮选机的结构和工作原理,重点分析了浮选机的槽体、叶轮、定子、刮泡机构、假底稳流板等关键部件的设计要求。浮选机清水性能试验表明:叶轮转速137.58 m/s,浸没深度895 mm时,浮选机工艺指标最优。45 m3机械搅拌式浮选机在大阳泉选煤厂的应用结果表明:改造后浮选精煤灰分为10.69%,尾煤灰分为55.35%,浮选精煤产率为68.03%,满足生产要求,且浮选机对不同粒级煤泥都有很好的回收效果。与FCMC3000浮选柱相比,在入料灰分相差不大的情况下,XJM-S45浮选机的尾煤灰分、精煤产率、可燃体回收率、浮选完善指标分别提高了18.61%、18.84%、23.90%、18.30%。     

Comparative study of the performance of conventional and column flotation when treating coking coal fines

Investigations were carried out on coking coal fines by conventional cell and column flotation techniques. The effects of different operating parameters were evaluated for both conventional and column flotation. The coal fines were collected from Bhojudih washery, India. These coal fines averaged 24.4% ash, 19.8% volatile matter and 53.8% fixed carbon on a dry basis. A commercial grade sodium silicate, light diesel oil and pine oil were used as depressant, collector and frother respectively. The flotation performance was compared with release analysis. The conventional flotation results indicated that a clean coal with 14.4% ash could be obtained at 78.0% yield with 88.4% combustible recovery. The ash of the clean coal could be further reduced to 10.1% at 72.0% yield with 85.6% combustible recovery by using column flotation. The column flotation results were close to those obtained by release analysis.     

Influences of Jameson flotation operation variables on the kinetics and recovery of unburned carbon

The purpose of this study was to investigate the influences of Jameson flotation operation variables on the recovery and kinetics of unburned carbon (UC). The waste sample of petroleum coke, filter powder or fly ash, used in the experiments was collected from lime calcination plant tailings. The effect of Jameson flotation parameters on the recovery and kinetics efficiencies of UC was systematically studied. The feasibility of separating unburned carbon and refuse was determined from the combustible recovery (CR) and ash reduction (AR) (%) curves. Within the range studied, the optimum diesel oil dosage was 3500 g/tonne, pine oil dosage was 2500 g/tonne, pulp density was 15%, wash water rate was 0.17 cm/s and downcomer immersion depth was 50 cm. The results indicate that the Jameson flotation technique is effective in removing the UC from waste filter powder. Furthermore, the classical first-order kinetic flotation model (R = R_∞ [1 − exp (− k ? t)]) was applied to data from the tests. The model was evaluated by statistical technique, after non-linear regression on the model parameters. It is found that the classical first order flotation kinetic model, most extensively used among flotation models, fits the tests data very well.     

A flotation study of refuse pond coal slurry

The flotation behavior of a refuse pond fine coal slurry sample was studied using mechanical and column flotation techniques. Flotation parameters investigated included type and dosage of frother and collector, agitation speed, scrubbing time, slurry pH, etc. for the mechanical flotation cell, and air flow rate, feed flow rate, and wash water flow rate for the column flotation. Flotation kinetics was also studied in the mechanical flotation cell. The results showed that the coal sample was very difficult to clean by flotation. Low yield (5–15%) and low combustible recovery (6–23%) and high product ash (about 22%) were obtained when methyl-isobutyl-carbinol (MIBC) was used as frother and #2 fuel oil as collector. Adjustment of operating parameters such as agitation intensity showed limited effects. However, flotation yield was significantly improved when MIBC and #2 fuel oil were replaced with frother P948 and collector SPP. Mechanical scrubbing was unable to restore the floatability of the coal sample. ‘Ken-Flote’ column flotation was inferior to mechanical flotation for oxidized coal and possible reasons were given.     

华恒选煤厂煤泥浮选的可行性研究

针对华恒选煤厂选煤方式单一、煤泥回收困难等问题,通过筛分试验、标准分步释放试验和煤泥浮选试验验证煤泥浮选的可行性。结果表明:煤泥中+0.5 mm产率较低,为0.18%,-0.25 mm产率为99.23%,符合煤泥浮选入料粒度要求;轻柴油和GF质量比9∶1,药剂用量为1000 g/t时,煤泥浮选效果最好,此时精煤产率为46.28%,精煤灰分为11.76%,可燃体回收率最高为73.99%,煤泥浮选可行。结合选煤厂实际情况分析了煤泥浮选的必要性,预测了增设煤泥浮选的经济效益,说明增设煤泥浮选系统在施工空间和工艺布置方面完全可行,增设煤泥浮选系统可优化选煤工艺,适应市场变化。浮选精煤可与精煤掺配销售,保持精煤水分稳定,减少因水分损失带来的亏吨现象,减少煤泥积压,缓解企业压力,增加销售收入1530.9万元/a。     

高性能环保选煤捕收剂N9858和N9836的应用研究

实验对比了N9858、N9836及柴油对不同煤种的浮选效果;对于难选的粗颗粒煤,N9858和N9836均显示出比柴油要优异很多的浮选性能,可燃体回收率提高16%,精煤灰分无变化。对于易选的细颗粒煤,N9858显示出更强的浮选能力,在用量为柴油的50%条件下,与柴油及N9836相比,可燃体回收率分别提高了5.90%和4.04%,精煤灰分无明显变化。N9858及N9836的实际浮选效果比柴油更加贴近理论的分步释放曲线。     

提高煤泥浮选捕收剂性能的试验研究

针对煤泥浮选捕收剂分散难、选择性差、用量大等问题,利用不同化工产品及表面活性剂,将煤油制备成复合捕收剂用于煤泥浮选。分别进行了煤油、复合捕收剂的优选试验及浮选速度试验。优选试验表明:当煤油用量为900 g/t,仲辛醇用量为450 g/t时,煤油浮选效果最佳;当Fy-4复合捕收剂用量为500 g/t,仲辛醇用量为450 g/t时,精煤灰分为9.96%,精煤产率为88.72%,可燃体回收率为94.82%,在精煤灰分相近的条件下,Fy-4复合捕收剂的用量比煤油降低了44.44%,精煤产率和可燃体回收率分别提高了0.06%和0.16%。浮选速度试验表明:Fy-4复合捕收剂不仅节省了药剂用量,而且提高了煤泥浮选活性,提升了精煤浮选速度。最后探讨了无机电解质NaCl对复合捕收剂浮选效果的影响,当NaCl浓度为0.05 mol/L时,煤泥颗粒Zeta电位更趋近零电点,降低了煤泥颗粒的相对接触角,改善了煤泥浮选效果。     

煤泥浮选起泡剂的优化试验

通过对原生煤泥的粒度分析,说明曙光煤业选煤厂煤泥属于高灰煤泥,煤泥中含有较多易泥化矿物质,这些矿物质在浮选过程中容易因机械夹带作用而进入精煤产品,影响精煤质量。以曙光煤业选煤厂原生煤泥为研究对象,分析了不同起泡剂种类和用量对煤泥浮选效果的影响。结果表明:GF油、仲辛醇、TY001的最优浮选药剂组合分别为煤油400 g/t、GF油45 g/t,煤油300 g/t、仲辛醇45 g/t,煤油400 g/t、TY001 45 g/t。当药剂用量相同时,从可燃体回收率看,仲辛醇作用效果最优,其次为TY001,GF油最差;从浮选完善指标看,TY001与仲辛醇性能相当,均明显高于GF油,精煤产率、浮选选择性明显提高,尾煤灰分均达到60%以上。从技术经济方面考虑,在精煤灰分Aj≤11%的条件下,选择煤油与仲辛醇组合较为适宜,最佳药剂用量为煤油300 g/t,仲辛醇45 g/t。     

Optimization of some parameters in column flotation and a comparison of conventional cell and column cell in terms of flotation performance

In this study, a comparative evaluation was made between column and mechanical flotation cells for fine coal cleaning. In addition, the optimum values of operating parameters were examined, which are important to achieve a desired separation performance in column flotation, such as the frother concentration, the collector dosage, the froth thickness, the wash water rate, the air rate and the feeding rate. The coal sample was collected from a classifying cyclone overflow stream consisting of nominally −130 μm material. Ash, volatile mater, fixed carbon and total sulfur contents of the sample were found to be 47.50%, 20.80%, 31.70% and 0.75%, respectively. Comparison of the column and mechanical flotation results indicated that column flotation was considerably more efficient than mechanical flotation for fine coal cleaning. High froth thickness and wash water addition during column flotation made it possible to obtain cleaner coals. The column flotation produced a 15.60% product ash with a 50.92% clean coal yield and 81.85% combustible recovery.     

Beneficiation of fine coal by using the free jet flotation system

The free jet flotation system was developed at the Berlin Technical University in 1985. This system was able to treat ultrafine particles of about −53 μm. In the present study, the fine size fraction of the coal (−0.5 mm) containing 45% ash taken from the Zonguldak Central Washery Plant (ZCWP) of Turkish Hard Coal was beneficiated by using the free jet flotation system. In the flotation tests, the best results were obtained in the case of using a mixture of 90% kerosene and 10% iso-octanol in the amount of 400 g/ton as a collector. Also, the optimum system parameters of a 30 l free jet type flotation (FJFT) cell used in this study were determined from the results of systematic tests. In the optimum free jet flotation conditions, the floating coal containing 18.73% ash with a combustible recovery of 72.4% was obtained.     

Performance of classic oils and lubricating oils in froth flotation of Ukraine coal

In this study, the appropriate collector and collector amount for Ukraine coal in froth flotation was determined. For this purpose, the performance of classic oils (kerosene, diesel-oil and fuel-oil) and lubricating oils (spindle oil, bright stock and heavy neutral) was evaluated by combustible recovery, ash rejection and efficiency index. It was found that the combustible recovery and ash rejection changed, depending on the type and concentration of oil. The maximum combustible recovery was obtained by using bright stock. It was determined that bright stock, fuel-oil and kerosene were suitable for the flotation of Ukraine coal. On considering the flotation efficiency index values, the best results were obtained with bright stock and diesel-oil. Consequently, it was shown that bright stock and spindle oil could be used as alternative oils instead of classic oils for cleaning of Ukraine coal by the froth flotation.     

抑制剂降灰浮选试验研究

为降低浮选精煤灰分,研究了抑制剂种类和用量对煤泥浮选降灰效果的影响,并选出最佳抑制剂种类和用量。结果表明:抑制剂的加入对浮选精煤降灰效果显著,但同时会对精煤产率和浮选完善指标造成一定影响。玉米淀粉的精煤灰分降低最大,但精煤产率和浮选完善指标降低速度更快,因此玉米淀粉作为抑制剂时,选择性较差,严重抑制低灰精煤上浮;亚硫酸钠的精煤灰分降低较少,浮选完善指标降低较快;CMC的精煤灰分降低较多,但同时精煤产率和浮选完善指标总体小于丹宁;丹宁的精煤灰分普遍较低,且精煤产率和浮选完善指标较高。因此,对于试验煤泥,丹宁用量为300 g/t时,降灰效果明显,精煤灰分为10.09%,满足精煤灰分(10±0.1)%的要求,同时对精煤产率和浮选完善指标影响最小,对矿物的抑制效果最优。     

田庄选煤厂提高精煤产率的措施

为提高选煤厂精煤产率,分析了田庄选煤厂设备工艺存在的问题,通过将粗煤泥脱泥筛下水导入粗煤泥分选机,粗煤泥分选机入料桶改为角锥池,增加稳流装置、溢流槽;合理优化煤浆分配桶,及时加入调整剂,完善粗煤泥角锥池,改造粗煤泥方池入料管道;改造粗煤泥筛喷水系统,保证重介质旋流器入料均匀等分别对粗煤泥系统、浮选系统和末煤系统进行改造,并对改造后的工艺效果进行评价。结果表明:改造后粗煤泥分选机0.5~0.25 mm入料产率提高了3.27%,小于0.25 mm入料产率降低了2.94%,粗煤泥分选机入料组成明显改善,提高了精煤产率。改造后浮选精煤灰分降低了0.43%,精煤产率和数量效率分别提高了6.01%和0.21%,浮选机浮选效率得以提升。粗煤泥筛筛分效率提高,脱泥效果改善,末煤重介质旋流器的精煤产率和数量效率分别提高了6.15%和3.61%。     

“2+2”模式重介质选煤系统煤泥及煤泥水处理首创工艺技术

"2+2"模式重介质选煤系统煤泥两级浮选、精煤泥两段脱水、尾煤泥水两段浓缩两段回收首创工艺技术,在多座选煤厂的应用结果表明,该工艺可解决我国炼焦煤选煤厂长期存在的以浮选精煤为主的精煤泥灰分、水分偏高的难题,可实现煤泥全部厂内回收、洗水闭路循环。     

FJC20-4A喷射式浮选机在望峰岗选煤厂的应用

通过对煤泥粒度组成及原煤小浮沉试验的研究可知,望峰岗选煤厂入选原煤属难选煤,浮选入料煤泥为极难浮煤。针对KHD浮选机存在的操作复杂,微泡析出量不足,浮选药剂用量大等问题,分析了FJC20-4A喷射式浮选机的工作原理及主要特点,并对两者的应用效果进行了对比。结果表明:与KHD浮选机相比,FJC20-4A型浮选机浮选精煤产率、尾煤灰分、可燃体回收率、浮选完善指标及浮选数量效率分别提高了22.04%、43.83%、26.51%、23.07%和18.08%,浮选抽出率增加了63.64%左右,浮选药剂消耗量降低了0.03 kg/t。最后对选煤厂效益进行了分析,说明FJC20-4A浮选机的应用使选煤厂生产工艺更加灵活,降低了工人的劳动强度和作业难度,增加了浮选剂的使用效率,选煤厂实际增加经济效益7219.96万元/a。     

Beneficiation of Coal Fines by Aggregative Flotation

The effect of various operating parameters on the performance of the aggregative flotation process for beneficiating coal fines was investigated. The recovery of carbonaceous matter was found to be improved by high mixing intensity and by the utilization of preemulsified collector in the aggregate formation stage. The presence of salt in the flotation stage was found to enhance recovery of the aggregates and the use of a three-stage aggregative flotation technique was found to recover more than 95% of the carbonaceous matter while rejecting 94% of the liberated ash (67% of the total mineral matter). This was accomplished using 2 kg of kerosene per tonne of coal while, in contrast, conventional flotation techniques yielded a recovery of 47% at a collector dosage of 7.5 kg/t.     

望峰岗选煤厂煤泥可浮性研究

通过对望峰岗选煤厂煤泥性质的分析,说明入浮平均粒度较粗,各粒级煤泥灰分均在30％以上,嵌布较均匀,单体解离度低,为浮选降灰带来困难;煤泥表面接触角较小为50．06。,说明其天然可浮性较差,经捕收剂十二烷或柴油处理后,煤泥接触角增大,煤的可浮性提高;若要求精煤灰分为14％,则标准浮选精煤产率约为65％。通过单因素试验确定煤浆质量浓度为80g／L,捕收剂用量为800∥t,起泡剂用量为128g／t时,煤泥浮选效果较好,浮选完善度最高为66．94％,精煤灰分符合要求,精煤产率较高为71．67％。最后以捕收剂、起泡剂和煤浆质量浓度为正交因素设计正交试验,考察各因素对煤泥可浮性的影响,并得出最佳浮选药剂制度。结果表明：当捕收剂用量为1000g／t,起泡剂用量为42g／t,煤浆质量浓度为60g／L时,煤泥浮选效果最好,此时精煤产率为71．59％,精煤灰分为14．30％,达到高产降灰的目的。     

细粒难浮煤泥浮选试验研究

分析了内蒙古能源中心选煤厂煤泥性质,说明试验煤泥是以高灰细泥为主的极难浮煤;高灰细泥在浮选过程中容易因夹带、黏附作用而进入精煤,影响精煤质量。通过探索试验发现,煤浆质量浓度为40∥L,捕收剂、起泡剂用量均为1．0kg／t时,煤泥浮选效果最好,此时精煤产率为53．53％,灰分为13．92％,但仍未达到厂家要求。为将精煤灰分降至11％以下,对煤泥进行二次浮选试验。当煤浆质量浓度为50g／L,捕收剂、起泡剂用量均为1．5kg／t,搅拌时间为1min时,二次浮选效果最好,此时精煤产率为52．78％,精煤灰分为10．14％,中煤产率为6．57％,中煤灰分为57．30％,尾煤产率为40．65％,尾煤灰分为76．81％,中煤可直接出售。二次浮选工艺可有效降低精煤灰分,提高精煤产率,解决了煤泥难浮问题,满足了生产需求。     

Effects of magnetic pretreatment on diesel oil properties and its relationship to low rank coal flotation

The effects of diesel oil pretreated with magnetic field on low rank coal flotation were investigated in this study. Flotation results demonstrated that combustible matter recovery increased with the magnetized time (MT) and magnetic field intensity (MFI), then plateaued while concentrate ash barely changed. The highest combustible matter recovery (73.86%) was obtained under 10 min of MT and 0.2 T of MFI. These results coincided with the analyses of interfacial tension and viscosity and supported by the results of SEM and contact angle measurements, indicating that magnetized diesel oil has a beneficial effect on low rank coal flotation.     

FCSMC-3000旋流—静态微泡浮选柱运行实践

兴华焦化厂采用静态微泡浮选柱技术回收煤泥中的精煤,当入料矿浆浓度为８０ｇ／Ｌ,灰分为１１％～１４％时,精煤回收率可达８０％,精煤灰分稳定在６％左右;回收的精煤掺入炼焦精煤中,生产的焦炭仍能达到出口焦炭质量标准。