作　　者： ; ;

机构地区： 南京农业大学资源与环境科学学院环境工程系

出　　处： 《岩石矿物学杂志》 2011年第6期1031-1038,共8页

摘　　要： 嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)能够在低pH值条件下,迅速将Fe2+氧化并产生大量次生羟基硫酸铁沉淀,从而除去水中可溶性Fe2+。这为富含Fe2+的酸性矿山废水(acid mine drainage,AMD)处理提供了新的思路。本文从晶种刺激和阳离子诱导两个方面,分别研究了固定化载体(硅藻土、石英砂)和具有强诱导能力的成矾离子(K+)对微生物转化酸性体系中Fe2+成次生矿物的影响。结果表明,3种材料均有明显促进可溶性Fe2+向次生矿物转化的作用,且总铁(TFe)沉淀率与3种材料的添加量呈正相关关系。在起始Fe2+浓度为160mmol/L,硅藻土、石英砂和钾离子最大添加量分别为10 g、10 g和80 mmol/L时,经过72 h反应后,TFe沉淀率分别比对照增加了8%、24%和20%。矿物中的Fe、K和S元素含量与溶液中的起始K+浓度有非常密切的关系,随着K+浓度的增大,矿物中的K和S含量逐渐增加,而Fe含量则相应减少。 Acid mine drainage（AMD）,resulting from the oxidation of iron pyrite（FeS2） and other sulfide minerals,is a major problem in coal-and metal-mining districts in that such water often has a lower pH and contains high concentrations of heavy metals as well as Fe and SO2-4.Preventing the formation or migration of AMD from its source is generally considered to be the preferable option.However,due to the practical operational difficulties in many locations,efforts are directed towards the collection and treatment of the effluent.There are various options available for AMD treatment,and lime neutralization seems to be the most widely-used method in the mining industry.Unlike Fe3＋,Fe2＋ is difficult to be precipitated unless pH is elevated to 8.5,thus,from the economic viewpoint,the oxidation of Fe2＋ to Fe3＋ prior to neutralization is required during the treatment of the Fe2＋-rich AMD.Acidithiobacillus ferrooxidans was proved to be efficient for the oxidation of Fe2＋ under low pH conditions.During the biological iron oxidation,abundant amounts of ferric iron oxyhydrosulfate（mainly jarosite） would precipitate.One of the advantages of the precipitate is the relative easiness of filtra-tion,thereby the problems associated with settling and filtering neutralized iron solutions are avoided.Therefore,the enhancement of the formation of ferric iron oxyhydrosulfate will favor the removal of soluble iron in AMD.Several factors affect the precipitation of ferric iron oxyhydrosulfate,such as temperature,initial pH,retention time,types and concentrations of jarosite-directing cations（K＋,Na＋,NH＋4,etc.） and the amounts of crystal seed.This paper reported the beneficial role of diatomite,quartz sand and K＋ in iron oxyhydrosulfate formation in the presence of A.ferrooxidans.It was found that both the rate and extent of the formation of iron oxyhydrosulfate precipitate increased with the increase of the amount of the three materials added to the reaction system.Compared with the control without the additi

关 键 词： 酸性矿山废水 嗜酸性氧化亚铁硫杆菌 羟基硫酸铁矿物 晶种 钾

领　　域： [天文地球] [天文地球] [生物学]