Production of a poly-alumino-iron sulphate coagulant by chemical precipitation of a coal mining acid drainage

The aim of this work was to produce a poly-alumino-iron sulphate coagulant from acidic coal mine drainage. Precipitating the iron and aluminium at pH 5.0, followed by dissolution in sulphuric acid, produced a coagulant consisting of 8.7% iron and 3.3% 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。     

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。     

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%。     

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。      

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。     

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.     

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。     

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%。     

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。     

寺湾矿矿井水除铁锰过程中的影响因素分析

对寺湾矿矿井水除铁、锰过程中的影响因素进行了试验分析,结果表明:影响铁的去除因素主要是混凝剂及其投药量,聚合氯化铝的最佳投药量为20mgL;影响锰的去除因素主要是滤料和滤速,采用高锰酸钾浸泡的锰砂作为滤料,滤速6～8mh,出水铁锰含量小于0.1mgL,满足回用要求,而且滤料成熟期只有1～2d,是一种高效的除锰技术。     

难沉降钨矿选矿废水处理研究

钨矿选矿过程中加入了大量的水玻璃和油酸，造成废水中残留大量水玻璃，使废水呈现黏稠的胶状，悬浮物难以沉降。目前国内外关于选矿废水处理的研究大多集中在选矿废水中有机选矿药剂的降解和重金属离子的去除，而对难沉降胶体的去除主要以传统的混凝剂聚合氯化铝（PAC）为主。本研究对不同的絮凝剂和助凝剂进行筛选组合并优化实验参数，使处理后选矿废水达到选矿用水水质要求。实验结果表明:基于实际选矿废水水质调研配制的模拟选矿废水pH值为1226，浊度为1 390 NTU，悬浮物（SS）为2 780 mg/L，Zeta电位为-59.9 mV；优化絮凝剂氯化钙（CaCl2）的投加量为500 mg/L，助凝剂1 500万分子量阳离子型聚丙烯酰胺（PAM）的投加量为30 mg/L，450 r/min快速搅拌反应5 min，160 r/min慢速搅拌2 min后静置沉淀20 min，则上清液浊度为7.11 NTU，浊度去除率高达99.48%。     

Synthesis of a Goethite Pigment by Selective Precipitation of Iron from Acidic Coal Mine Drainage

Conventional treatment of acid rock drainage (ARD) from coal mines generates large volumes of sludge, which requires further treatment and disposal. The aim of this work was to study the recovery of iron by selective precipitation to synthetize goethite for use as pigment. Goethite particles were successfully produced, and presented a particle distribution in the range of nano- and micro-sizes, varying from 0.04 to 5.0 µm when produced as paste suspension, or from 0.04 to 25.0 µm when dried at 60?°C and converted to a solid powder. The pigment was used to color a white cement paste, giving it a yellow ochre color. ARD treatment plants can adopt this process to reduce waste disposal issues and produce a valuable mineral (e.g., yellow pigment for concrete).     

International Trials of Vertical Flow Reactors for Coal Mine Water Treatment

Vertical flow reactors (VFRs) were tested at coal mine sites in New Zealand, South Korea, and the USA. The objective was to evaluate the iron removal efficiency and iron removal mechanisms during field trials at low pH and circumneutral pH, and to evaluate the potential use of VFRs as stand-alone systems or in combination with other passive treatment technologies. Total iron and manganese removal efficiencies at circumneutral pH (6–8) often exceeded 90%, with effluent concentrations less than 1 mg/L. This is attributed to both homogeneous and heterogenous Fe(II) oxidation and filtration of the precipitated ferrihydrite. Iron removal efficiencies at moderately acidic conditions (pH 3–4.5) averaged close to 40%, with an average 71.0% removal in one of the trials after iron removal capacity was stabilized. Microbial Fe(II) oxidation and precipitation as schwertmannite together with aggregation of colloidal and nano-particulate Fe(III) are suspected to be the main removal mechanisms. Iron solubility limited removal under very acidic conditions (pH < 3). The reproducibility of the results with respect to previous research confirmed that VFRs can be used as stand-alone passive treatment systems for iron removal from mine waters with a footprint less than half of the area required by a conventional aerobic wetland. A VFR can also provide useful iron pretreatment for other passive treatment systems under circumneutral conditions, but would have to be combined with alkaline generating systems to achieve full iron removal from acidic mine waters.

     

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。     

从刚果(金)铜萃余液中回收钴和铜及萃余液的循环利用

为了从刚果（金）某湿法炼铜厂铜萃余液中回收钴和铜,并实现萃余液的循环利用,采用除铁—沉铜—第一段沉淀钴—第二段沉淀钴工艺流程处理含钴铜萃余液。结果表明,采用该工艺分别得到铁渣、铜渣、粗氢氧化钴和第二段钴渣,铁渣中钙含量26.79%、铜含量0.05%、钴含量0.12%,除铁过程中铜和钴损失率分别为4.64%和3.14%;铜渣含铜3.74%、含钴2.06%;粗氢氧化钴中钴含量32.83%;第二段钴渣含钴7.14%;钴总回收率大于95%。铁渣用于建筑材料,铜渣返回浸出系统回收铜和钴,粗氢氧化钴可直接外售,第二段钴渣经萃余液调浆返回除铁工序,第二段沉钴后溶液回用作磨矿补加水,有价金属和处理后的废液都得到了资源化利用。经生产实践检验,该处理工艺具有良好的经济、环境和社会效益。      

矿井水净化处理混凝剂投加控制技术

混凝剂投加控制是矿井水净处理工艺过程中的关键环节,其结果直接影响到矿井水处理效果。当采用转子流量计或计量泵混凝剂控制技术时,在处理水量和水质变化时,混凝剂的投加量不能及时改变,从而影响矿井水净化处理效果;采用单因子流动电流混凝剂投加控制技术时,由于矿井水中含有一定量的乳化液和机油,使单因子流动电流传感器产生较大的误差,因此阻碍了该技术在矿井水净化处理中的应用;而混凝剂自动投加控制技术ADSMD在数学模型的基础上,由模拟试验取得工艺技术参数,再通过在线传感器、变送器、PLC、上位机和计量泵实现控制,从而确保了出水水质,并可降低运行成本,提高了矿井水处理技术的自动化水平。     

KR脱硫渣中鳞片石墨的回收

铁水脱硫过程中溶于铁水中的过饱和碳会以石墨的形式析出,本文针对铁水脱硫渣中含有石墨的特点,以煤油为捕收剂,2#油为起泡剂,采用浮选法进行回收,同时采用球磨、磁选对回收的石墨进行物理除杂,然后用盐酸、氢氟酸混酸进行化学提纯,制备得高纯鳞片石墨。研究表明:石墨回收率随着浮选剂投加量的增加先增加后减小,在煤油和2#油总投加量为1200 g/t、煤油∶2#油= 4∶1时,回收率超过97%;球磨使杂质从石墨表面剥离,磁选则降低石墨中的含铁物质,“球磨+磁选”处理可以使显著降低石墨中杂质含量,通过三次“球磨+磁选”后,石墨中的固定碳含量由58%提高到88%以上。混酸处理在较佳条件下可以将石墨的灰分降至0.03%,达到高纯石墨标准。扫描电镜分析表明回收的鳞片石墨与天然鳞片石墨在外形和结构上均无明显差异。      

用膨润土制备造纸废水处理用混凝剂的研究

介绍一种采用膨润土制备造纸黑液废水处理用混凝剂的方法。经过正交试验 ,选择出了优化工艺条件 ;产品经应用于碱法麦草浆黑液废水絮凝 ,获得了良好效果