硫酸盐还原菌处理矿山酸性废水的研究进展

系统地综述了硫酸盐还原菌(SRB)的还原机理,分析了影响硫酸盐还原菌还原作用的因素以及SRB处理方法的优点,提出了SRB处理酸性矿山废水(MAD)发展趋势。     

硫酸盐还原菌处理矿山酸性废水的试验研究

采用上流厌氧反应器连续处理矿山酸性废水,研究了水力停留时间、进水pH值、进水负荷对硫酸根还原效果的影响。获得最佳工艺参数为水力停留时间8 d,COD/SO^2-₄=1.6,进水SO^2-₄浓度2.3 g/L和进水pH=6.0。在温度30 ℃,HRT=8 d、COD/SO^2-₄=1.6,进水SO^2-₄浓度2.3 g/L,进水pH=4.5和废水稀释倍数为3倍的条件下,采用上流厌氧反应器连续成功运行59 d,反应器运行24 d后,硫酸根平均去除率为75.35%,铜离子的去除率达99.98﹪, 铁离子的去除率为88.87%,出水达到工业排放标准。     

硫酸盐还原菌利用不同生物质碳源对酸性矿山废水的处理

针对多组分酸性矿山废水(Acid Mine Drainage,AMD)污染严重,治理费用高的特点,基于硫酸盐还原菌(Sulfate-Reducing Bacteria,SRB)处理AMD具有成本低、适用性强、环境友好等诸多优点,从长期受煤矸石淋溶水污染的土壤中纯化培养一株SRB,并采用廉价易得的玉米芯、甘蔗渣和花生壳作为SRB生长碳源分别构造1号,2号,3号组动态柱,进行处理AMD的模拟实验,以探讨SRB利用生物质碳源处理AMD的有效性和规律性。各动态柱分别按照正交试验最优配比进行装填,其中,1号柱中SRB生物量和60目玉米芯按固液比分别为106. 8∶100(mg∶m L)和3. 5∶100(g∶m L)装填,2号柱中SRB生物量和100目甘蔗渣按固液比分别为71. 2∶100(mg∶m L)和4. 5∶100(g∶m L)装填,3号柱中SRB生物量和100目花生壳按固液比分别为106. 8∶100(mg∶m L)和4. 5∶100(g∶m L)装填。实验结果显示,以100目甘蔗渣为碳源的2号柱处理AMD的效果较好,对SO_4~(2-),Fe~(3+),Mn~(2+),Cr~(6+),Cr~(3+)平均去除率分别为61. 63%,99. 81%,72. 35%,96. 8%,100%,而体系出水的p H值和ORP值分别为6. 38～7. 30,-246 m V,表明SRB以甘蔗渣为碳源时的生长代谢活性优于玉米芯和花生壳,甘蔗渣可实现较持久的碳源供应。通过反应前后生物质材料的SEM和XRD分析表明,大量的Fe元素主要通过生物质材料的化学吸附方式被去除,而Mn和Cr元素主要通过与硫酸盐还原菌的代谢产物反应生成金属硫化物沉淀除去,少部分金属元素通过生物质材料的物理吸附被去除。同时,反应前生物质材料表面结构完整,反应后的生物质材料结构被破坏并附着纳米级金属硫化物沉淀。     

硫化物种类对处理酸性矿山废水的生物硫酸盐还原产物抑制作用

Moosa S.等人在《Hydrometallurgy》2006年83卷第1/4期发表文章,介绍了硫化物种类对处理酸性矿山废水的生物硫酸盐还原产物抑制作用。普遍认为,硫酸盐还原的产物(即形成的各种硫化物)对生物过程有抑制作用。为了提供对这种抑制动力学的了解,作者利用在醋酸盐上生长的完整的氧化     

硫酸盐还原菌及在处理硫酸盐废水中的作用

介绍了硫酸盐还原菌(SRB)的分类、培养和代谢机理及硫酸盐废水来源、硫酸盐还原菌处理废水的原理和当前研究的热点。     

陶粒微环境对硫酸盐还原菌生长的影响

以自制粉煤灰/生物质生物陶粒作为固定化硫酸盐还原菌(SRB)载体,研究不同初始pH值条件下,陶粒与SRB的相互作用对陶粒表面微环境pH值的影响、pH值对细菌生长和固定的影响,及对SO42-去除率的影响.加有陶粒的培养基pH值迅速趋向6.5～7.5,使陶粒表面微环境有利于SRB的生长,固定在陶粒上的SRB比对应悬浮的SR...     

硫酸盐还原菌示范工程概述

介绍使用硫酸盐还原菌（SRB）处理和控制酸性矿山排水（AMD）新技术的半工业性试验和现场试验结果。当有碳和硫酸盐源供给时,硫酸盐还原菌（一种普通的厌氧菌群）生产出硫化氢和重碳酸盐。硫化氢与AMD中金属离子起反应,生成金属硫化物而沉淀。生成的重碳酸盐用来促进酸性矿山排水的中和。半工业性试验金属去除系数达到：Zn99%,Al99%,Mn96%,Cd98%和Cu96%。但Fe和As去除不如上述金属有效,这主要是由于污染有机给养基的铁和砷含量高。有证据说明,吸附作用和硫酸盐还原都在反应器中发生。SRB现场示范工程包括使用蒙大拿州埃利斯顿附近的利利－奥芬博伊矿淹没的地下矿山工作区作为“原地生物反应器”。该矿在4年的监测期间,已观察到Al、Cd、Cu和Zn都有高的去除系数（70％－接近100％）。然而,由于与半工业性试验类似的原因,As和Fe测得低的去除系数。通过矿山水中硫酸盐减少的测定和可溶硫化物的检测说明,硫酸盐还原是明显的。     

酸性矿山废水形成与处理中的微生物作用

介绍硫酸盐还原菌(SRB)法处理酸性矿山废水的机理、影响因素和发展现状,指出目前酸性矿山废水处理中存在问题并提出解决方法。     

用SRB修复污染的酸性矿山废水

《Hydrometallurgy》2005年77卷(1~2)期上发表了Luptarova A·文章,介绍用硫酸盐还原菌(SRB)修复被重金属污染的酸性矿山外排废水的研究成果。随采矿活动的进行,酸性矿山外排废水(AMD)已成为威胁环境的主要问题。这种利用SRB去除AMD中重金属的方法是基于SRB在该环境下产生HS-,从而使重金属生成溶解度较小的硫化物沉淀。反应式如下:4 H2 SO42- H SRBHS- 4 H2O,有机质(C·H·O) SO42-SRBHS- HCO3-,Me2 HS-MeS H 。作者以2种不同的方法,考察了SRB对样品溶液中沉淀Cu2 的动力学。第一种方法使用1个反应器,在该反应器种,…     

硫酸盐还原菌示范工程概述

介绍使用硫酸盐还原菌 (SRB)处理和控制酸性矿山排水 (AMD)新技术的半工业性试验和现场试验结果。当有碳和硫酸盐源供给时 ,硫酸盐还原菌 (一种普通的厌氧菌群 )生产出硫化氢和重碳酸盐。硫化氢与AMD中金属离子起反应 ,生成金属硫化物而沉淀。生成的重碳酸盐用来促进酸性矿山排水的中和。半工业性试验金属去除系数达到 :Zn 99% ,Al 99% ,Mn 96 % ,Cd 98%和Cu 96 %。但Fe和As去除不如上述金属有效 ,这主要是由于污染有机给养基的铁和砷含量高。有证据说明 ,吸附作用和硫酸盐还原都在反应器中发生。SRB现场示范工程包括使用蒙大拿州埃利斯顿附近的利利 奥芬博伊矿淹没的地下矿山工作区作为“原地生物反应器”。该矿在 4年的监测期间 ,已观察到Al、Cd、Cu和Zn都有高的去除系数 ( 70 %～接近 1 0 0 % )。然而 ,由于与半工业性试验类似的原因 ,As和Fe测得低的去除系数。通过矿山水中硫酸盐减少的测定和可溶硫化物的检测说明 ,硫酸盐还原是明显的。     

酸性矿山废水中表面钝化技术的研究进展北大核心

酸性矿山废水(AMD)是最为严重的环境污染之一,主要由黄铁矿氧化引起。AMD的治理主要有末端处理和源头控制两条途径,末端处理技术不能从根本上解决污染问题,因此从源头控制黄铁矿的氧化是治理AMD的根本途径。源头控制技术主要有覆盖法、杀菌法和表面钝化法等,表面钝化法是目前科研工作者的研究热点。在介绍AMD成因的基础上,综述了各种表面钝化技术。重点概述了有机硅烷、载体-微胶囊化、自修复等技术的研究现状,分析了不同方法的优缺点,并针对其不足之处提出了今后的研究方向。为解决黄铁矿氧化问题、实现AMD污染的有效治理提供参考。     

污泥厌氧发酵-硫酸盐还原菌耦合体系产电性能和处理酸性矿井水的研究

为原位治理高硫煤矿区酸性矿井水,建立微生物燃料电池污泥厌氧发酵-硫酸盐还原菌耦合体系,考察了电极类型、阳极面积、极间距、离子浓度对产电性能和处理酸性矿井水中的硫酸盐效果的影响。单因素试验结果表明,碳布为阳极、极间距适中(3 cm)时,产电最佳;阳极面积越小、NaCl浓度越高,功率密度越大;硫酸根去除率的最佳条件为：碳布为阳极、极间距为5 cm、离子浓度适中,阳极面积越大,对硫酸根去除率越高。以硫酸盐去除最佳条件构建单室无膜碳片为阳极的耦合产电体系,所产生的最大功率密度为2.093 3 mW/m 2,10 d后污泥的COD去除率为43%,废水SO 2-4的平均去除速率达194.4 mg/(L·d -1),最高去除率为64%,比开路时的SO 2-4去除率提高24%。污泥厌氧发酵-硫酸盐还原菌耦合产电体系可同时实现降解剩余污泥和处理含SO 2-4废水。     

Using permeable reactive barriers for the treatment of acid rock drainage

Acid mine drainage (AMD) is the most serious environmental problem facing the Canadian mineral industry today. It results from oxidation of sulphide minerals (e.g. pyrite or pyrrhotite) contained in mine waste or mine tailings and is characterized by acid effluents rich in heavy metals that are released into the environment. A new acid remediation technology is presented, by which metallurgical residues from the aluminium extraction industry are used to construct permeable reactive barriers (PRBs) to treat acid mine effluents. This technology is very promising for treating acid mine effluents in order to decrease their harmful environmental effects.     

Fate of sulphate removed during the treatment of circumneutral mine water and acid mine drainage with coal fly ash: Modelling and experimental approach

The treatment of acid mine drainage (AMD) and circumneutral mine water (CMW) with South African coal fly ash (FA) provides a low cost and alternative technique for treating mine wastes waters. The sulphate concentration in AMD can be reduced significantly when AMD was treated with the FA to pH 9. On the other hand an insignificant amount of sulphate was removed when CMW (containing a very low concentration of Fe and Al) was treated using FA to pH 9. The levels of Fe and Al, and the final solution pH in the AMD–fly ash mixture played a significant role on the level of sulphate removal in contrast to CMW–fly ash mixtures. In this study, a modelling approach using PHREEQC geochemical modelling software was combined with AMD–fly ash and/or CMW–fly ash neutralization experiments in order to predict the mineral phases involved in sulphate removal. The effects of solution pH and Fe and Al concentration in mine water on sulphate were also investigated. The results obtained showed that sulphate, Fe, Al, Mg and Mn removal from AMD and/or CMW with fly ash is a function of solution pH. The presence of Fe and Al in AMD exhibited buffering characteristic leading to more lime leaching from FA into mine water, hence increasing the concentration of Ca²⁺. This resulted in increased removal of sulphate as CaSO₄·2H₂O. In addition the sulphate removal was enhanced through the precipitation as Fe and Al oxyhydroxysulphates (as shown by geochemical modelling) in AMD–fly ash system. The low concentration of Fe and Al in CMW resulted in sulphate removal depending mainly on CaSO₄·2H₂O. The results of this study would have implications on the design of treatment methods relevant for different mine waters.     

Preparation of immobilized sulfate reducing bacteria (SRB) granules for effective bioremediation of acid mine drainage and bacterial community analysis

Heavy metal-resistant immobilized sulfate-reducing bacteria (SRB) granules were prepared to treat acid mine drainage (AMD) containing high concentrations of multiple heavy metal ions using an up-flow anaerobic packed-bed bioreactor. The bioreactor demonstrated satisfactory performance at influent pH 2.8 and high concentrations of metals (Fe 463 mg/L, Mn 79 mg/L, Cu 76 mg/L, Cd 58 mg/L and Zn 118 mg/L). The effluent pH ranged from 7.8 to 8.3 and the removal efficiencies of Fe, Cu, Zn and Cd were over 99.9% except for Mn (42.1–99.3%). The bacterial community in the bioreactor was diverse and included fermentative bacteria and SRB (Desulfovibrio desulfiricans) involved in sulfate reduction. The co-existing anaerobic fermentative bacteria (Clostridia bacterium, etc.) with the ability to use lactate as electron donor could explain the differences between actual lactate consumption and what would be expected based solely on sulfate reduction.     

The application of wood ash as a reagent in acid mine drainage treatment

The paper deals with a possible utilisation of wood ash as a reagent in treating acid mine drainage (AMD) from opencast mining of brown coal. Wood ash samples were obtained having combusted deciduous and coniferous tree wood in a household furnace. The dominant mineral phases in wood ash are calcite, quartz, lime and periclase. The used AMD is characteristic of high contents of sulphates, iron, manganese, heavy metals and low pH. The AMD treatment process included dosing of wood ash to adjust pH values about 8.3 (a dose of 0.5 g l⁻¹) or calcium hydroxide (a dose of 0.2 g l⁻¹) for comparison. The reaction time was 20 min. Dosing of wood ash in AMD resulted in an increase of pH in solution from 3.5 to 8.3, which caused the removal of metal ions mainly by precipitation, co-precipitation and adsorption. Comparing the application of Ca(OH)₂ in AMD treatment, at an almost identical pH value the concentrations fell in both cases for Fe, Mn, As, Co, Cu, Ni, Zn, Mg, Al and Mo. Applying wood ash the drop was even more distinct in Mn, Zn and Mg. The results of sedimentation tests in an Imhoff cone confirm that the settling capacities of sludge using wood ash are significantly better than when using calcium hydroxide in acid mine drainage treatment.     

Remediation of acid mine drainage using metallurgical slags

In this study basic oxygen and stainless steel slag were both assessed for potential use in treating acid mine drainage. The stainless steel slag was able to effect some pH change but was found to not be suitable. Basic oxygen slag was found to have a significant potential as a remediating agent. For a model acid mine water with a pH of 2.5, sulfate concentration of 5000 mg/L and iron concentration of 1000 mg/L, the slag was able to increase pH to 12.1, reduce the soluble iron by 99.7% and reduce sulfate by 75% in batch experiments. In these batch reactors most reaction was completed within 30 min indicating that this is a rapid process. Additional experiments were conducted with continuous flow reactors to assess the maximum treatment capacity of the slag. These experiments indicated that slag replacement strategies are wholly dependent on the strength of the acid mine drainage, the required residence time and the specified residual concentrations of iron or sulfate and the pH. The data indicate that in particular, basic oxygen furnace slag has significant potential as a replacement reagent for lime in treating acid mine drainage.     

Start-up,adjustment and long-term performance of a two-stage bioremediation process,treating real acid mine drainage,coupled with biosynthesis of ZnS nanoparticles and ZnS/TiO2 nanocomposites

Acid mine drainage (AMD) generation is a widespread environmental problem in Europe, including Portugal. Previous experience has shown that a combined process consisting of an anaerobic sulphate-reducing bioreactor, following neutralization with calcite tailing, produces water complying with legal irrigation requirements from synthetic AMD. Aiming the treatment of real AMD a new bioreactor was inoculated with a SRB enrichment obtained from sludge from a local WWTP anaerobic lagoon. In the initial batch phase, sulphate supplementation was needed to achieve high sulphate-reducing bacteria counts before continuous feeding of AMD was started. The system quickly achieved good performance, proving it is easy to start-up. However, this time the neutralization step failed to keep bioreactor affluent pH higher than 5 for longer than three weeks. This was due to armouring of calcite by precipitates of various metals present in AMD. A new configuration, replacing a packed-bed column by a shallow contact basin, proved to be more robust, avoiding clogging, short-circuiting and providing long-term neutralization. The treated effluent, with excess of biologically generated sulphide, was successfully used to synthesize zinc sulphide nanoparticles, both in pure form and as a ZnS/TiO₂ nanocomposite, thus proving the feasibility of coupling an AMD bioremediation system with the synthesis of metal sulphide nanoparticles and nanocomposites.     

The effect of particle size on acid mine drainage generation: Kinetic column tests

The rate of acid mine drainage (AMD) generation is directly proportional to the surface area and so to the particle size distribution of acid-forming minerals exposed to oxidation. Materials in various particle sizes are subject to weathering processes at field condition; however, the particle size dependent oxidation rate has not been investigated for understanding entire geochemical behavior at a mining site. Therefore, a comprehensive research program was aimed to investigate the effect of particle size on pH variation and acid mine drainage generation using kinetic column tests, and then to find convenient methodologies for upscaling laboratory-based results to the field condition. For this purpose, ore samples collected from Murgul Damar open-pit mining were grinded in three different particle size distributions that are coarse (minus 22.5 mm), medium (minus 3.35 mm) and fine (minus 0.625 mm) sizes, 34 columns were designed in different dimensions for kinetic column tests. It was found that the cumulative concentration of the many constituents measured from medium particles (minus 3.35 mm) are higher than coarser samples due to decreasing specific surface area with increasing particle size. Similarly, because of decreasing of hydraulic conductivity with increasing the fine content, the cumulative concentration of constituents measured from medium particles (minus 3.35 mm) are also higher than finer particles (minus 0.625 mm). Based on statistical and analytical analyses of the results of kinetic column tests, the time required to initiate acid formation at field condition varied between 489 and 1002 days depending on particle size distribution. In addition, considering the effect of particle size and the results of related statistical analysis, main oxidation (SO₄²⁻) and neutralization (Ca²⁺, Mg²⁺, Mn²⁺ etc.) products were also successfully upscaled to the field condition.