硫酸盐还原菌处理酸性矿山废水研究进展

酸性矿山废水的处理对环境可持续性至关重要。目前,利用硫酸盐还原菌修复酸性矿山废水因高效经济、环境友好、绿色安全等优势,备受国内外研究学者的关注。因此,本文通过对有关硫酸盐还原菌处理酸性矿山废水文献进行梳理,综述了酸性矿山废水的来源及危害,总结了硫酸盐还原菌去除酸性矿山废水中高硫酸盐和金属的机理,详细介绍了影响硫酸盐还原菌处理酸性矿山废水的主要因素,阐述了基于硫酸盐还原的生物反应器系统。最后,对硫酸盐还原菌处理酸性矿山废水的研究进行展望并提出建议。     

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。     

硫酸盐还原菌治理地浸采铀地下水的柱实验研究

以新疆某地浸采铀矿山为实例,通过柱实验研究了硫酸盐还原菌去除地浸采铀污染地下水中铀和硫酸盐等污染物的潜力.实验结果表明,硫酸盐还原菌可有效去除地浸采铀矿山地下水中的污染物U(Ⅵ)和SO2-4,U(Ⅵ)的去除率可达94.5%,硫酸根去除率为75.3%,地下水的pH值可达到近中性.U(Ⅵ)和硫酸根都是作为硫酸盐还原菌的电子受体而通过生物还原去除的.研究结果为地漫废水的原住修复提供了新的生物技术思路.     

高效硫酸盐还原菌对煤矸石硫污染的修复作用

利用从黄土中分离的硫酸盐还原菌修复煤矸石酸性污染,以乳酸钠作碳源,探讨了加不同量碳源和不同接种量情况下硫酸根的去除率,并对煤矸石浸液的pH值、氧化还原电位和电导率的变化作定量测定,研究了硫酸盐还原菌的几种影响条件.实验结果表明:利用硫酸盐还原菌来修复煤矸石酸性污染的思路可行,向煤矸石中接种硫酸盐还原菌硫酸根最高转化率可达95.5%,可提高煤矸石浸液的pH值,降低其氧化还原电位和电导率,从源头上抑制酸矿水的产生,能有效控制含硫煤矸石在降雨酸性淋溶的环境污染.     

某硫酸盐还原菌株的分离及其在煤矸石山酸化污染修复中的应用

煤矸石堆场氧化导致的高盐酸性废水是严重危害煤矿区环境质量的污染源之一。利用硫酸盐还原菌进行生物固硫,能够有效控制煤矸石氧化产酸及其造成的污染。针对已知的硫酸盐还原菌多为严格厌氧菌、依赖外加碳源、难以应用于露天煤矸石山的问题,从酸性煤矸石堆场周边土壤中分离、筛选出一株兼性厌氧硫酸盐还原菌,分析菌株的16S r RNA基因序列、形态和生理生化特性,并利用柱状淋溶实验测定该菌株对煤矸石酸化污染的修复效果。结果表明:该菌株与Bacillus subtilis具有99.93%同源性,外形为杆状,大小(0.4～0.6)μm×0.2μm,最适生长温度范围为25～35℃,在p H为4～8的环境中均生长良好。该菌株对外加碳源的依赖性低,在无任何外加碳源的好氧条件下,接种该菌株18 d后,可将已酸化煤矸石的p H由3.09提升至4.62,同时去除48.25%的硫酸盐离子和88.40%以上的重金属离子,有效控制煤矸石堆场高盐酸性废水的产生。     

培养SRB处理高浓度硫酸盐废水

通过富集培养SRB菌,检测后分离纯化,处理高浓度硫酸盐废水,硫酸根还原率达到92.73%.并阐述了SRB还原硫酸根的几个影响因素,并提出了这方面研究存在的问题.     

煤系地下水的硫酸盐还原菌与水文地球化学效应

为探索煤系地下水的硫酸盐异常偏低的机理,从井下705 m深钻孔地下水中分离得到1株硫酸盐还原菌GY-2,经16S rRNA测序及序列对比,鉴定为滴状脱硫肠状菌（Desulfotomaculum guttoideum）。实验结果显示,该菌株只在厌氧条件生长,适宜环境为中温、中性-弱碱性、中低矿化度的封闭含水地层,Fe 2+ 对菌株生长有显著促进作用。菌株的发现证实了煤系深部地下水的还原作用和硫酸盐还原菌的存在,对部分煤矿区地下水（HCO - 3 +CO 2- 3 ）/SO 2- 4 之比随着地层的埋深逐渐加大,而由大到小再到大的规律用硫酸盐还原作用和地下水氧化还原电位与水质类型对应关系作出了解释。     

某硫酸盐废水处理工艺的设计

某企业生产产生的硫酸盐废水pH值7.7,硫酸盐、COD、铁、锰等含量超标,原部分排入周边水体,污染周边生态环境及饮用水源,影响农业生产。为消除废水中含量超标的硫酸盐,设计了处理工艺流程,并确定了设备选型。小型模拟试验结果表明,该硫酸盐废水处理后,出水硫酸盐含量低于250 mg/L,满足相关规定要求,且废水处理成本仅1.4元/t,可为该硫酸盐废水工业处理流程的确定提供参考。     

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。     

Waste from Biodiesel Manufacturing as an Inexpensive Carbon Source for Bioreactors Treating Acid Mine Drainage

Abstract.  Alcohol-fed, semi-passive bioreactors have been used to support the growth of sulfate-reducing bacteria (SRB) for treatment of acid drainage from mine sites. An alcohol source not previously examined for use in these reactors is the glycerol-methanol waste remaining after the production of biodiesel fuel. In the laboratory, rock-filled columns were used to investigate biodiesel waste (BDW) as a carbon source for SRB. Columns were provided with water containing 900 mg/L sulfate, and fed reagent-grade glycerol or BDW in sufficient quantity to reduce 50% of the sulfate. Addition of 246 mg/L of reagent-grade glycerol resulted in 50% sulfate reduction and production of up to 59 mg/L of soluble sulfide, while the equivalent of 246 mg/L of glycerol provided as BDW resulted in 55% sulfate reduction and the production of up to 92 mg/L of soluble sulfide. During the initial stages of acclimation, propionic, acetic, formic, and lactic acids were observed. Acid concentrations were reduced over time in the effluent, and organic carbon in the BDW was nearly completely converted to carbon dioxide.     

硫酸根和硝酸根对ZVI-SRB处理铀废水的影响研究

利用硫酸盐还原菌(SRB)和还原性铁粉(Zero Valent Iron,ZVI)还原沉淀废液中的铀,研究了硫酸根和硝酸根对SRB体系和ZVI-SRB体系还原沉淀废液中的铀的影响.试验结果表明,这2个酸根离子对SRB体系和ZVI-SRB体系处理铀废水有一定的影响.硫酸根的质量浓度低于4000mg/L对硫酸盐还原菌还原沉淀铀没有影响,但当硫酸根的质量浓度超过6000mg/L时,铀的去除率会显著下降,从80%以上降到14.1%;有硫酸根时,铀的最终除去率ZVI-SRB联合处理比SRB单独处理要高.低浓度的硝酸根有助于SRB的还原代谢,高浓度的硝酸根抑制SRB的生长代谢,进而影响铀废水的处理效率,当硝酸根的质量浓度达到1500mg/L,铀的去除率不到0.1%,而硝酸根的质量浓度低于1000mg/L,铀的去除率可达75%以上;有硝酸根时,加铁粉的SRB的铀除去率比没加铁粉的去除率都要低.     

硫酸盐还原菌复合碳源的筛选

利用硫酸盐还原菌(Sulfate-Reducing Bacteria, SRB)的生物法可以有效去除酸法地浸采铀地下水中的硫酸根和重金属离子,是一种有发展潜力的酸法地浸采铀地下水修复技术。酸法地浸采铀地下水中的有机物含量较低,无法满足硫酸盐还原菌的生长代谢,需要向其提供充足的碳源。通过复合碳源筛选试验,发现混合比为10∶1的玉米芯和牛粪混合发酵液能够满足SRB生长代谢的需要,且该复合碳源能被SRB充分利用而不增加处理后酸法地浸采铀地下水的COD,可以作为生物法修复酸法地浸采铀地下水的SRB碳源。     

Simultaneous Removal of Copper, Zinc, and Sulfate from Coal Mine Waste in a Laboratory SRB Bioreactor Using Lactate or Ethanol as Carbon Sources

The feasibility of inoculating coal mine waste piles with sulfate-reducing bacteria (SRB) to prevent the production of acidic leachates containing sulfate and metal contaminants was evaluated in batch and column bioreactors. The results showed that SRB growth and activity could be attained in the presence of acidic (pH 4.5) coal mine waste using lactate or ethanol as a carbon source, while no obvious growth was found at pH <3.5. Inoculation of coal mine waste in batch reactors with lactate or ethanol as a carbon source resulted in efficient neutralization and high removal of sulfate and metals. Similar results were attained in dynamic-flow columns inoculated with SRB. SEM-EDS analysis of the precipitates showed iron sulfide to be the main component. This study indicates that SRB could possibly be used to prevent or limit acidic drainage from coal mine waste piles.     

Microbially Mediated Thallium Immobilization in Bench Scale Systems

Results from bench-scale tests for thallium remediation in mining-impacted water are presented and removal mechanisms are discussed. The source water consisted of surface runoff mixed with groundwater from an inactive gold mine in central Montana. Bench scale columns were operated under continuous flow for 225 days to test for microbially-mediated thallium immobilization. Various compositions of straw and steer manure in a gravel matrix provided a source of organic nutrients and sulfate-reducing bacteria sufficient to initiate and maintain microbial sulfate reduction up to 270 mmol/m³d. Hydraulic residence times of 2.7 days produced an aqueous thallium effluent concentration below the analytical detection limit of 2.5 μg/L at 20°C in all the tested columns. These effluent levels were achieved for influent dissolved thallium concentrations varying from 450 to 790 μg/L. An increase in pH between influent (pH 6.9) and effluents (pH 7.5) was observed. Hydraulic conductivity remained relatively constant during the course of the experiments and varied for the different test columns between 0.2 and 10 cm/s. The highest k-values were observed in the horizontal flow column. In addition to the column tests, sterile serum-vial experiments were performed to confirm that thallium sulfide (Tl₂S) formation and precipitation was the most likely mechanism for thallium removal. Data from the bench-scale experiments were utilized for the design of an on-site pilot-scale passive treatment system.     

活性白土酸性废液的综合利用研究

活性白土是以膨润土与硫酸经高温反应制成的。对活性白土及其活化过程中产生的酸性废液的组成进行了分析。提出了在活性白土生产工艺流程中,循环使用硫酸酸性废液以提高硫酸的利用率,并从废液中回收铝盐制备硫酸铝铵与聚合硫酸铝等化工产品。不仅使硫酸原料与膨润土矿产资源得到充分利用,节约了硫酸,增加了非金属矿产的附加值,提高了经济效益;且从根本上消除和减少了污染源,减少了硫酸及其盐类的排放,降低了污水处理成本,利于环保。     

Arsenic,Selenium, and Sulfate Removal using an Ethanol-Enhanced Sulfate-Reducing Bioreactor

A laboratory scale sulfate-reducing bioreactor column study was used to investigate removal of arsenic, selenium, and sulfate in neutral to alkaline simulated mine water. Selenium was effectively removed as insoluble elemental selenium from 200 μg/L to below the maximum contaminant level (50 μg/L). With the addition of ferrous chloride in the influent, arsenic was also effectively removed to near the maximum contaminant level (10 μg/L). Sulfate removal was apparently limited by the presence of undissociated hydrogen sulfide, which was found to limit sulfate-reducing bacterial activity in the range of 20–40 mg/L and will need to be considered for sulfate-reducing bacteria treatment system designs.     

Desulfuromonas alkenivorans S-7联合稻壳处理酸性重金属废水

为了研究硫酸盐还原菌和稻壳联合生物反应器在重金属废水处理中作用及机理。利用实验室前期分离鉴定的硫酸盐还原菌Desulfuromonas alkenivorans S-7联合填充稻壳柱式生物反应器处理人工合成酸性重金属(Fe~(3+),Mn~(2+),Cr~(6+))废水。比较了废水处理过程中理化特性(pH,E_h,E_c)及3种重金属离子变化规律,并利用FT-IR光谱仪分析了微生物和稻壳联合处理作用下重金属离子去除特性。研究结果表明:S-7能够明显提高酸性废水的pH,20 d后pH最终稳定在6.20左右,也能使反应体系维持在较高的还原环境并降低体系的电导率。S-7菌株对3种代表性离子都有一定的处理效果,对Fe,Mn,Cr三种金属离子的去除效率分别为FeMnCr。反应器处理前期废水中离子的去除速率较快,后期由于离子共存对废水处理的影响使废水中金属离子浓度趋于平衡,出现动态制约平衡,S-7菌株对3种重金属离子的去除机制可能存在差异。处理后期由于Cr~(6+)浓度上升明显,增大了SRB反应器中的重金属含量,明显影响SRB反应器的稳定性能;稻壳填充对S-7菌株生长能够稳定维持SRB反应器的厌氧环境,并且稻壳对金属离子去除也存在一定程度的物理吸附作用。FT-IR分析表明:S-7菌体处理废水时会吸附Fe,Mn,Cr离子,其中羟基、胺基、酰胺基及羧基是发生吸附作用重要的官能团;稻壳在处理重金属废水前后,稻壳的Si—O—Si和羰基在处理重金属废水中可能发挥了作用。     

Acid mine water treatment using engineered wetlands

During the last two decades, the United States mining industry has greatly increased the amount it spends on pollution control. The application of biotechnology to mine water can reduce the industry's water treatment costs (estimated at over a million dollars a day) and improve water quality in streams and rivers adversely affected by acidic mine water draining from abandoned mines. Biological treatment of mine waste water is typically conducted in a series of small excavated ponds that resemble, in a superficial way, a small marsh area. The ponds are engineered to first facilitate bacterial oxidation of iron; ideally, the water then flows through a composted organic substrate that supports a population of sulfate-reducing bacteria. The latter process raises the pH. During the past four years, over 400 wetland water treatment systems have been built on mined lands as a result of research by the U.S. Bureau of Mines. In general, mine operators find that the wetlands reduce chemical treatment costs enough to repay the cost of wetland construction in less than a year. Actual rates of iron removal at field sites have been used to develop empirical sizing criteria based on iron loading and pH. If the pH is 6 or above, the wetland area (m²) required is equivalent to the iron load (grams/day) divided by 10. Theis requirement doubles at a pH of 4 to 5. At a pH below 4, the iron load (grams/day) should be divided by 2 to estimate the area required (m²).