Dissimilatory reduction of Fe~III (EDTA) with microorganisms in the system of nitric oxide removal from the flue gas by metal chelate absorption

IntroductionThecombustionoffossilfuelsgeneratesSO2 andNOxpollutantswhichcauseairpollutionandacidrain .Existingfluegasdesulfurization(FGD)scrubbersinvolvelimestoneprocesses,whichareefficientforcontrollingSO2 emission ,butareincapableofremovingalmostwater i…     

固定化微生物法处理含甲硫醇恶臭气体

采用液相曝气方式驯化培养污水厂活性污泥，获得具有降解甲硫醇能力的优势微生物菌群。同时用海藻酸钠包埋固定化微生物，研究固定化微生物颗粒填充床去除甲硫醇恶臭气体的工艺过程。液相曝气培养研究表明：降解甲硫醇的微生物菌群适宜的ｐＨ值为５．２～９．０，最佳ｐＨ条件为弱碱性。已驯化微生物的离心浓缩回收率为７１．２％，颗粒填充床生物脱臭塔运行实验表明：在空塔停留时间不大于１３ｓ，对低浓度甲硫醇气体（〈１２．９ｍ     

蔬菜土壤微生物种群数量与土壤重金属含量的关系

对呈贡县蔬菜土壤微生物种群数量和土壤重金属质量分数进行大田调查分析，结果表明，土壤微生物种群数量和微生物多样性指数变化较大，土壤微生物种群数量总体水平较高，但微生物多样性指数偏低，其中以细菌占较大的优势；土壤重金属对土壤微生物数量和微生物多样性均有一定的影响，其中土壤中Pb和Cu的质量分数与土壤微生物种群数量显著相关；土壤重金属综合污染指数与真菌／细菌个数比例、真菌／放线菌个数比例与微生物多样性指数均呈显著的指数相关。随着重金属综合污染指数的增加，微生物多样性指数呈指数式地迅速下降。     

水解-混凝法处理糖蜜酒精废水试验

采用投加优势菌群的水解 -混凝法对糖蜜酒精废水进行试验 ,研究投加优势菌的水解阶段的处理效果 ,同时 ,以 10 %碱式AlCl3为混凝剂 ,对水解段的出水进行混凝处理 ,并对处理条件进行研究。结果表明 ,采用投加优势菌群的水解 -混凝法工艺处理该废水 ,可以取得 5 8%的CODCr去除率 ,且可去除一定的色度     

微生物还原浸出法回收废旧电池粉末中的金属锰

驯化培养K1、K2、K3 3株锰还原异养微生物,使微生物耐受电池重金属离子的能力提高.通过微生物的还原作用将二氧化锰还原成二价锰离子回收利用.微生物利用MnO2作为代谢呼吸链最终电子受体,传递氧化有机物产生的电子,还原溶浸锰于介质中.与其他菌株相比,K1菌株表现出很强的金属耐受性,最终浸出率可达93%.     

挥发性有机废气生物处理技术研究进展

随着现代工业的快速发展,带来的挥发性有机废气(VOCs)排放到大气中,逐渐增加的VOCs已成为当今关注的重要环境问题之一。生物净化VOCs具有易操作、维护方便、净化效率高、运行费用低、安全性高、无二次污染等优点而备受世界各国的广泛关注。VOCs废气生物处理技术原理是将有机污染物在微生物作用下转换为无害或者低害的物质,而微生物则起到了至关重要的作用。综述了生物滤池、生物滴滤、生物洗涤3种净化工艺的原理和研究进展,将3种反应器优缺点进行了对比;最后论述了该技术当前存在问题及发展趋势。     

Amazonian deforestation and soil biodiversity

Clearance and perturbation of Amazonian forests are one of the greatest threats to tropical biodiversity conservation of our times. A better understanding of how soil communities respond to Amazonian deforestation is crucially needed to inform policy interventions that effectively protect biodiversity and the essential ecosystem services it provides. We assessed the impact of deforestation and ecosystem conversion to arable land on Amazonian soil biodiversity through a meta-analysis. We analyzed 274 pairwise comparisons of soil biodiversity in Amazonian primary forests and sites under different stages of deforestation and land-use conversion: disturbed (wildfire and selective logging) and slash-and-burnt forests, pastures, and cropping systems. Overall, 60% and 51% of responses of soil macrofauna and microbial community attributes (i.e., abundance, biomass, richness, and diversity indexes) to deforestation were negative, respectively. We found few studies on mesofauna (e.g., microarthropods) and microfauna (e.g., protozoa and nematodes), so those groups could not be analyzed. Macrofauna abundance and biomass were more vulnerable to the displacement of forests by pastures than by agricultural fields, whereas microbes showed the opposite pattern. Effects of Amazonian deforestation on macrofauna were more detrimental at sites with mean annual precipitation >1900 mm, and higher losses of microbes occurred in highly acidic soils (pH < 4.5). Limited geographic coverage, omission of meso- and microfauna, and low taxonomic resolution were main factors impairing generalizations from the data set. Few studies assessed the impacts of within-forest disturbance (wildfires and selective logging) on soil species in Amazonia, where logging operations rapidly expand across public lands and more frequent severe dry seasons are increasing the prevalence of wildfires.     

再生水利用的病原微生物浓度限值探讨

采用微生物定量风险评价的方法,结合北京市某城市污水回用工程,对再生水用于园林绿化、道路冲洗与降尘等市政用途时的病原微生物浓度限值进行了探讨.提出的限值为:大肠埃希氏杆菌70个/L、沙门氏菌0.5 CFU/L、志贺氏菌0.1CFU/100L、甲肝病毒0.001 PFU/100L、轮状病毒1.2×10^-3PFU/100L、脊髓灰质炎病毒0.07 PFU/100L、柯萨奇病毒0.04PFU/100L、埃可病毒0.05 PFU/100L、隐孢子虫卵囊0.1个/100L、贾弟鞭毛虫卵囊0.03个/100L.     

几种生物学指标与生物强化系统降解效率的关系

针对炼油废水生物强化处理系统中有时存在的不稳定造成排水超标的问题,研究了SBR反应器中采用生物强化技术,其细菌数量、脱氢酶、邻苯二酚1,2-双加氧酶(C12O)和邻苯二酚2,3-双加氧酶(C23O)等关键生物学指标与污染物去除效率的综合对应关系,并运用ERIC-PCR技术研究了运行前后处理系统内微生物群落的变化.结果表明,投加菌剂的生物强化处理系统提高了细菌数量和酶活,使处理效率明显提高.生物强化系统中细菌数量及C23O酶活与污染物去除效率呈正相关关系,且微生物群落结构十分稳定.C12O为一种诱导酶,其酶     

Habitat function of agricultural soils as affected by heavy metals and polycyclic aromatic hydrocarbons contamination

Ecotoxic activity of soils polluted with polycyclic aromatic hydrocarbon (PAH) and heavy metals (HM) was evaluated in pot and laboratory experiments. Plants and soil microorganisms were chosen as test organisms and six different soil materials were used in the study. The applied levels of HM and PAH were aimed to reflect environmental conditions in the "worst case" situation. Zn(2+), Pb(2+) and Cd(2+) were introduced to the soils as an aqueous solution of the mixture of salts at the concentrations corresponding to 1000, 500 and 3 mg kg(-1), respectively. Mixture of four PAH compounds (flourene, anthracene, pyrene and chrysene) as a CH(2)Cl(2) solution was applied at levels of 10-100 mg summation operator 4PAH kg(-1). Population and activity of soil microflora was evaluated as measured of total bacteria counts, intensity of respiration and enzyme activity (dehydrogenases and phosphatases). Effect on plants was evaluated on the base of the growth (plant at an early stage of their development) and yield (mature plant) measurements. The results indicate that combined effect of PAH and heavy metals on soil microorganisms activity and on some plants at an early stage of their development can be stronger than in soils amended with HM or PAH separately. Reaction of tested organisms was related to soil properties, PAH concentration, time and plant species. Mature plants (maize) were insensitive to the applied levels of both group of contaminants.