Production of a Poly-ferric Sulphate Chemical Coagulant by Selective Precipitation of Iron from Acidic Coal Mine Drainage

The aim of this work was to produce a ferric sulphate rich solution from acidic coal mine drainage that could be used as coagulant. Precipitating the iron at pH 3.8, followed by dissolution in sulphuric acid, produced a coagulant consisting of 12.4% iron and 1.3% aluminium. Water treatment tests proved that this coagulant was as efficient as the coagulant chemicals conventionally used in water treatment plants. The process can be easily incorporated into conventional AMD treatment plants, thereby reducing sludge waste issues and producing a valuable chemical reagent.     

PBS混凝剂处理造纸综合废水

研究了用酸浸的粉煤灰和鼓风炉铁泥作原料制备PBS混凝剂并用于造纸废水的处理结果表明．PBS混凝剂与聚硅酸铝（PSA）絮凝剂配合处理造纸废水．在pH值为7．0、混凝剂的投加量为60mg／L的条件下，SS、CODcr和色度的去除率分别为92．4％．85．2％和91．6％与Al2（SO4）3和FeCl3常规混凝剂相比．PBS混凝剂的混凝沉降性能明显优于常规混凝剂。     

铅锌矿选矿废水处理与回用试验研究

用聚合硫酸铁(PFS)、聚合氯化铝(PAC)和明矾3种混凝剂对铅锌选矿废水进行了处理,试验结果表明聚合氯化铝效果较佳,当用量(以铝计)为40 mg/L,Pb2+去除率可达87.14%,而废水中具有还原性的有机浮选药剂的去除率只有20.25%,在混凝沉降的基础上采用活性炭吸附进一步去除废水中残留的浮选药剂,当活性炭用量为100 mg/L时,Pb2+去除率为93.24%,浮选药剂的去除率可达56.32%。将处理过的废水进行铅锌浮选试验,试验结果表明废水采用混凝沉降—吸附工艺处理后的浮选指标与清水相当,表明该工艺处理后的废水可用于浮选生产。     

改善铝板冲压性能的有效途径

分析了连铸连轧铝坯的组织和性能特点。通过调整铝合金铸轧坯的化学成分，使其中铁含量大于0．3％，Fe/Si＞1；并采用适宜的熔炼、轧制工艺以及热处理制度，可以有效改善由连续铸轧坯生产的冷轧铝板材的冲压性能。     

Bioprocessing of pyrite concentrate from coal tailings for the production of the coagulant ferric sulphate

The aim of this work was to produce a high concentration ferric sulphate solution from coal pyrite tailings that could be used as coagulant for water and wastewater treatment. At laboratory scale it was performed the oxidation of pyrite in an aqueous medium in a packed bed leaching column in an oxidizing environment with the presence of acidophilic bacteria (Acidithiobacillus ferrooxidans) as well as nutrients for bacterial growth. It was indicated that an aqueous solution rich in ferric sulphate can be produced which was found suitable for application in water treatment plants.     

热电厂废弃资源的综合利用

采用粉煤灰作原料制备聚硅酸铝 (PSAA)混凝剂 ,并通过化学沉淀、络合、凝聚和絮凝等反应将其用来处理热电厂含氟废水。结果表明 ,本法处理成本低廉、过程简单、实用、排渣少 ,实现了资源的充分利用。     

某低品位含铁铝土矿选矿试验研究

在工艺矿物学的基础上,对河南某低品位含铁铝土矿进行了选矿试验研究,采用优先磁选选铁,磁选尾矿经过分级后进行浮选选铝。经过一次粗选、一次精选和一次扫选得到铝精矿。在粗选段进行了不同的条件试验,并从中选取了最优条件。在最佳条件试验的基础上进行了闭路试验,获得铁精矿TFe含量60. 48%,铝精矿Al_2O_3含量65. 46%、A/S为6. 32的良好指标。     

四川某赤铁矿石选矿试验

中钢集团安徽天源科技股份有限公司,安徽 马鞍山 243000 四川某铁矿石属低硫磷高硅铝酸性弱磁性铁矿石,铁主要以赤铁矿的形式存在。为了给该赤铁矿石的开发利用提供依据,采用粗粒强磁干选-细粒高梯度强磁选-中矿再浮选工艺对其进行了选矿试验。结果表明：原矿破碎、筛分成40~15 mm和-15 mm两部分后,40~15 mm粒级经YCG-350×1000永磁辊式粗粒强磁选机干选,可获得产率为20.42%、铁品位为52.67%、铁回收率为22.47%的的合格块精矿;-15 mm粒级和干选尾矿磨至-0.074 mm占85%后经SLon高梯度强磁选机1次粗选、1次精选、1次扫选,可获得铁品位为60.35%、铁回收率为32.46%的高梯度强磁选铁精矿;高梯度强磁选中矿经脂肪酸类捕收剂NZ 1粗2精正浮选,又能获得铁品位为60.39%、铁回收率为13.11%的浮选铁精矿,从而使综合铁回收率达到68.04%。     

Neutralizing Coal Mine Effluent with Limestone to Decrease Metals and Sulphate Concentrations

Abstract.   This paper describes pilot scale tests of a novel process for the neutralisation of acidic mine water. Leachate from a waste coal dump was neutralised with limestone, and iron, aluminium, and sulphate were removed. Specific aspects studied were: the process configuration; the rates of iron oxidation, limestone neutralisation, and gypsum crystallisation; the chemical composition of the effluents before and after treatment; the efficiency of limestone utilisation; and the sludge solids content. The acidity was decreased from 12,000 to 300 mg/L (as CaCO₃), sulphate from 15,000 to 2,600 mg/L, iron from 5,000 to 10 mg/L, aluminium from 100 to 5 mg/L, while the pH increased from 2.2 to 7.0. Reaction times of 2.0 and 4.5 h were required under continuous and batch operations respectively for the removal of 4 g/L Fe (II). The iron oxidation rate was found to be a function of the Fe (II), hydroxide, oxygen, and suspended solids (SS) concentrations. The optimum SS concentration for iron oxidation in a fluidised-bed reactor was 190 g/L. Up-flow velocity had no influence on the rate of iron oxidation in the range 5 to 45 m/h. Sludge with a high solids content of 55% (m/v) was produced. This is high compared to the typical 20% achieved with the high density sludge process using lime. It was determined that neutralisation costs could be reduced significantly with an integrated iron oxidation and limestone neutralisation process because limestone is less expensive than lime, and a high-solids-content sludge is produced. Full scale implementation followed this study.     

Ferric Sulphate Coagulant Obtained by Leaching from Coal Tailings

A ferric sulphate solution was produced from pyritic coal tailings for potential use as a coagulant for water and wastewater treatment. Laboratory-scale leaching experiments were carried out with four tailings with different concentrations of pyrite. The tailings were characterized for: total sulphur, pyritic sulphur, sulphate sulphur, organic sulphur, and elemental analysis of carbon, hydrogen, and nitrogen. X-ray diffraction analyses were also conducted to assess the mineral composition of the samples. The leaching was carried out using a laboratory column constructed as a packed bed reactor with a closed-circuit sprinkling system. After 4 weeks of leaching, the liquor was filtered and evaporated to reach an iron concentration of about 12% w/w, which is typical of most commercial FS coagulants in Brazil.     

改性膨润土吸附强化混凝处理微污染水源水

针对微污染水源水中有机物、氨氮含量较高问题,采用改性膨润土作为吸附剂吸附有机物、氨氮以强化混凝效果。通过不同混凝剂、助凝剂以及不同改性膨润土的对比实验研究,确定吸附混凝最佳联用方式。结果表明：PAC混凝效果优于PFS,壳聚糖助凝效果优于PAM,加活性炭450℃焙烧2 h为膨润土的最佳改性条件。加活性炭450℃焙烧改性膨润土吸附反应30 min后再加PAC混凝剂、壳聚糖助凝剂的吸附-混凝联用,是去除微污染水源水中有机物、氨氮及浊度的最佳处理方法,对微污染水源水CODMn值降低率为65.4%,氨氮、浊度去除率分别可以达到56.7%、97.4%,可取得良好处理效果,值得推广应用。     

由膨润土制取氧化铝晶须试验研究

研究了由膨润土制取氧化铝晶须的方法,确定了适宜的工艺路线。通过XRD、SEM、TG等手段对前驱体碱式碳酸铝铵及其煅烧产物氧化铝晶须的结构、成分、形貌进行了分析与表征。结果表明,在较佳酸浸条件下,膨润土中的蒙脱石基本被全部分解,其中的铝等可溶性成分溶于酸中,而硅变成了活性二氧化硅与石英等脉石残留在酸浸渣中;酸浸滤液经高锰酸钾氧化沉铁后,铁含量显著降低,除铁率96%以上;利用水热合成的前驱体碱式碳酸铝铵晶须,经900～1100℃温度煅烧4h后得到不同晶型的氧化铝晶须,其直径在500nm左右,长度约为10μm,长径比为20左右。     

混凝法处理锰矿选矿废水及最优水力条件的试验研究

选取聚合氯化铝(PAC)、聚合硫酸铁(PFS)和聚丙烯酰胺(PAM)作为混凝剂,采用正交试验,以去浊率与去锰率作为综合评价指标,探讨了不同混凝剂处理锰矿选矿废水的效果及最佳的水力条件。结果表明,以PAC作为混凝剂时,对混凝效果影响最大的是快搅时间,其最优G值和GT值:混合G值1643.1s-1,GT值147879.0;反应G值325.2s-1,GT值195120.0。以PFS作为混凝剂时,对混凝效果影响最大的是投药量,其最优G值和GT值:混合G值3265.0s-1,GT值97950;反应G值188.7s-1,GT值56610.0。以PAM作为混凝剂时,影响最大的是投药量,其最优G值和GT值:混合G值3265.0s-1,GT值293850.0;反应G值277.7s-1,GT值333240.0。并且PAM对锰矿选矿废水的处理效果最优,去浊率与去锰率分别为94.6%和96.4%。     

浅谈絮凝控制技术

分析了给水处理工艺中絮凝剂和助凝剂的使用情况;对目前净化处理的重要环节———絮凝控制技术在各水厂的不同应用措施及优缺点进行了阐述,重点介绍了在目前国内应用较广泛的单因子控制投加技术。     

熔融还原处理低品位氧化锌矿的研究

利用熔融还原法的基本原理, 对低品位氧化锌矿的处理进行研究;分析了铁浴熔融还原法和铝浴熔融还原法的基本理论,进行了实验研究, 并各自考察了温度、时间、碱度的影响。得到以下适宜的工艺条件:铝浴法, 还原温度1 100 ℃, 时间45 min, 碱度(四元)1.1;由此试验条件得到以下技术指标:氧化锌粉中ω(ZnO)=98 %～99%, ω(Pb)=1.0%左右, 锌挥发率大于90%, 锌回收率预计达95%, 渣中ω(Zn)<3%, ω(Pb)<0.2 %;与现有的火法处理方法相比, 初步认为熔融还原法更适于处理氧化锌矿。     

机械力化学活化煤矸石一步制备高效混凝剂

以含高岭石类煤矸石为例，提出了利用高能球磨活化工艺诱导煤矸石中高岭石晶体结构破坏，并与硫酸混合一步制备粉末铝基混凝剂，代替传统的高温活化酸碱工艺的新思路。所制备的混凝剂通过XRD、TEM、CP/MAS NMR进行表征，并对浊度、正磷酸根、五价砷、及腐殖酸等多种污染物质的去除率来对该混凝剂性能进行评价。结果表明该混凝剂具有高活性并对以上四种污染物的去除率分别达到95.95%、91.2%、89.6%和93.73%。所制备的混凝剂能够成为现有铝基混凝剂的替代品，该制备工艺简单、清洁、环保、经济，拓展了含高岭石煤矸石尾矿利用新途径，并为更廉价而又高效的混凝剂的使用提供了可能。      

劣质高岭土制备高效混凝剂聚硅酸铝及应用

本文研究了以劣质高岭土为原料制备高效混凝剂聚硅酸铝(PSA)的方法，确定了合理的生产工艺和操作条件。用该混凝剂处理工业废水，并与传统混凝剂进行了比较，结果表明，PSA混凝剂处理效果好，用药量少。     

混凝沉淀-吸附法处理萤石选矿废水的正交试验研究

采用正交实验法,研究了混凝沉淀-吸附法处理萤石选矿废水过程中混凝剂用量、沉淀剂用量和吸附剂用量对选矿废水中Ca²⁺和COD去除效果的影响。结果表明,在混凝剂CSP-12用量12 mg/L、沉淀剂碳酸钠用量900 mg/L、吸附剂活性炭用量200 mg/L条件下,水处理效果最佳,此时Ca²⁺去除率达91.26%,COD去除率达60.54%。     

某难选高铁高磷锰矿石同步还原分离实验研究

本文针对云南某地锰品位13.88％、铁品位19.87％的贫锰铁矿石,在常规物理选矿方法分选效果不佳的情况下,采用干式抛尾-还原焙烧-弱磁选铁-选铁尾矿强磁选锰工艺处理该矿石.该流程最终获得铁品位53.89％、回收率65.53％的铁精矿和锰品位27.11％,锰回收率为70.26％锰精矿,为处理类似低品位铁锰矿石起到了一定的借鉴作用.     

化学混凝法处理选矿废水的实验研究

采用混凝法处理广西河池某锡矿废水,探讨了该废水处理的最佳混凝剂和最佳的混凝条件。结果表明,FeCl3·6H2O(FC)是最佳混凝剂,在pH=8.0时,每300mL的废水中投加0.40mL质量分数为5%的FeCl3·6H2O后,再投加0.20mL质量分数为0.1%聚丙烯酰胺(PAM)是处理该废水的最佳用量,废水经处理后浊度从2700NTU降到2.0NTU以下。