微生物燃料电池技术净化废水研究进展

重点介绍了微生物燃料电池的原理和微生物燃料电池技术在废水净化中的应用,并从微生物燃料电池的结构、微生物菌种种类、影响因素等方面分析了微生物燃料电池技术在废水净化过程中存在的问题,对今后的研究提出了建议。     

在氧化沟中构建微生物燃料电池

在氧化沟中构建了微生物燃料电池,经测定微生物燃料电池电压为0.24～0.39 V,均值为0.29 V.经计算该微生物燃料电池的产电功率为0.05～0.15 mW,均值为0.08 mW.构建了微生物燃料电池的氧化沟COD去除率为75％～ 90％,TN去除率为5％～38％;无微生物燃料电池的氧化沟COD去除率为77％～89％,TN去除率为5％～23％.构建微生物燃料电池后能减少氧化沟内外沟中污泥的增加量,约减少15％.     

用燃料电池纯化水的同时产生氢气

一种在纯化水的过程中可产生稳定电流的微生物燃料电池现在被改进用来产生氢气。美国Penn州立大学的Logan B E等人首先设计了一种直流微生物燃料电池，可以利用生长在碳质阳极上的细菌氧化废水中的有机物。氧化过程产生的氢离子和电子在阴极与空气中的氧气结合生成水，同时产生电流。细菌具有一种“发酵屏障”，限制了其将碳水化合物完全降解为CO2和H2的能力，但是Penn州立大学的研究人员已确定，     

日本岐阜大学采用生物燃料电池发电并回收磷

<正>日经技术在线(日),2014-12-04日本岐阜大学流域圈科学研究中心研究人员于2014年12月2日宣布,该中心通过微生物燃料电池,成功地利用含有猪粪尿等的畜产废水发电,并回收了磷材料。微生物燃料电池利用一种称之为"发电菌"的微生物分解有机物时产生的电子进行发电。在废水处理时,还可在除去废水中的有机物的同时回收电能。另外,岐阜大学的研究人员通过研究发现,     

有机固体废物生物法制氢的研究进展

综述了利用有机固体废物生物法制氢的原理和研究现状。城市有机固体废物、农业有机废物、工业有机废物是生物法制氢的主要原料。暗发酵制氢是利用有机废物厌氧消化的产酸阶段而产氢，pH、温度、水力停留时间、氢气分压、原料性质、微量元素含量、产甲烷微生物抑制剂等均影响氢气产率。光发酵制氢是利用光合厌氧细菌将挥发性有机酸转化为氢气和二氧化碳。暗发酵和光发酵制氢时，生物固定化有利于高速连续产氢。在有机废物处理和生物法制氢方面，暗发酵一光发酵、暗发酵一微生物燃料电池的组合工艺是具有前景的技术。今后的研究方向是原料的预处理技术、选育高效产氢菌株、发明高效反应器、优化处理工艺和处理条件等。     

微生物固定CO2技术及其应用

全面介绍了自养微生物固定CO2的研究进展及应用,包括固定CO2的微生物种类、微生物固定CO2的机理、微生物固定CO2技术的发展趋势及在CO2吸收与资源化中的应用.提高微生物的固定CO2能力、简化固定CO2环境要求、拓展微生物固定CO2的应用领域是微生物固定CO2技术及其应用的发展方向.     

多环芳烃污染土壤的微生物修复技术

对生物修复技术中的微生物进行了分类，并阐述了微生物生物降解土壤中多环芳烃（PAHs）的基本原理。在此基础上，分析了国内外微生物生物修复技术的发展概况，采用图示法重点综述了原位处理技术和非原位处理技术的工艺流程，并列举了相应的工程应用实例。     

固定化微生物处理工业废水

本文综述了固定化微生物在环境保护方面的应用及发展情况;介绍了固定化微生物作为新型废水处理剂的特点及处理废水的有关技术,并与传统生化法作了比较;指出开发固定化微生物处理工业废水的技术关键;分析了这项新技术的发展前景。     

固定化微生物技术在废水处理中的研究进展

介绍了固定化微生物的载体和制备方法，综述了固定化微生物技术近年来在废水处理中的应用现状，并提出今后的研究方向和发展前景。     

采用固体氧化物燃料电池反应器脱除H2S

采用固体氧化物燃料电池反应器脱除H2S，反应器以Co-Mo双元硫化物作电催化剂，Zr掺杂的BaCeO3（BCZY）为固体电解质。研究了燃料电池的燃料气流量、反应温度和电流密度等参数对H2S去除率的影响。结果表明：在反应温度为800℃、燃料气流量为30mL／min的条件下，H2S去除率达71％；在测量的电流密度区间内，H2S去除率与电流密度之间呈线性关系。电能回收实验结果表明，当采用掺杂5％（质量分数）BCZY的Co—Mo双元硫化物作为阳极时，单体燃料电池输出电压达0．68V，最大电功率密度为3．5mW／cm2。因此，燃料电池技术脱除H2S是一种废气资源化的有效手段。     

Programs assessing implementation and effectiveness of state forest practice rules and BMPs in the West

The major forest nonpoint source control programs in the West are largely regulatory, either under forest practices acts (California, Idaho, New Mexico, Nevada, Oregon, and Washington) or a streamside management act (Montana). These programs and the specific rules they enforce continue to undergo intensive scrutiny. Still, the questions are the same for these regulatory programs as for states that base nonpoint source control on voluntary BMPs (Arizona, Colorado, Utah, Wyoming). Are the rules or BMPs being applied, and are they effective in reducing nonpoint source pollution to levels that protect beneficial uses of water? The level of debate about forestry in the West has resulted in detailed monitoring and research to answer these questions. In the past, state agencies have assumed levels of BMP compliance based on the percent of operations without enforcement actions. These estimates are being replaced by statistically valid and reproducible monitoring of forest practices rules and BMP compliance levels. BMP effectiveness is being assessed using both qualitative and quantitative methods. This can involve field assessments, process-based research, and control watershed studies. Some trend monitoring is also beginning. With the regional implementation rate for forestry BMPs at about 94% and rising, it is likely that effectiveness testing will continue to be a priority and consume the majority of assessment resources for this region.     

Effect of Coconut, Sisal and Jute Fibers on the Properties of Starch/Gluten/Glycerol Matrix

Coconut, sisal and jute fibers were added as reinforcement materials in a biodegradable polymer matrix comprised of starch/gluten/glycerol. The content of fibers used in the composites varied from 5% to 30% by weight of the total polymers (starch and gluten). Materials were processed in a Haake torque rheometer (120 °C, 50 rpm) for 6 min. The mixtures obtained were molded by heat compression and further characterized. Addition of lignocellulosic fibers in the matrix decreased the water absorption at equilibrium. The diffusion coefficient decreased sharply around 5% fiber concentration, and further fiber additions caused only small variations. The thermogravimetric (TG) analysis revealed improved thermal stability of matrix upon addition of fibers. The Young’s modulus and ultimate tensile strength increased with fiber content in the matrix. The storage modulus increased with increasing fiber content, whereas tanδ curves decreased, confirming the reinforcing effect of the fibers. Morphology of the composites analyzed under the scanning electron microscope (SEM) exhibited good interfacial adhesion between the matrix and the added fibers. Matrix degraded rapidly in compost, and addition of increased amounts of coconut fiber in the matrix caused a slowdown the biodegradability of the matrix. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may be suitable.     

Quantification of Polymerisation Processes During The Oxidative Degradation of 14C-Labelled Chlorophenols

In experiments employing the lignocellulose-decaying basidiomycetes Trametes versicolor and Stropharia rugosoannulata degrading uniformly¹⁴C-labelled 2,4-dichlorophenol and pentachlorophenol, acombination of size exclusion chromatography (SEC),fractionation, and -scintillation counting wasapplied to quantify polymerisation products formed duringchlorophenol degradation. Time-dependent mass balances weregenerated by analysis of ¹⁴C in polymerisation products,CO₂, as well as monomer non-polar and polar metabolites.Approximately 30% of the chlorophenols were found to bepolymerised. A major fraction of the polymerised productscorresponded to a molecular weight range from 0.24 – 40 kDa.Only a minor fraction could be attributed to a molecularweight >40 kDa. This method proved to be useful inquantification of polymerisation products and kinetics of thepolymerisation processes, whereas UV/Vis detection ofpolymerisation products separated by SEC led to false positiveresults. The SEC-¹⁴C method could also be applied forother complex processes where polymerisation ordepolymerisation occurs (humification, degradation oflignocellulose, formation of bound residues from xenobioticssuch as polycyclic aromatic hydrocarbons or 2,4,6-trinitrotoluene) and where spectrophotometric determinationsare difficult or impossible.     

The Relative Influences of Primary and Secondary Particulates to Urban Air Quality in the United Kingdom

This study uses a combination of data from U.K. monitoringstations and from modelling undertaken with the U.K.Meteorological Office's NAME Model to investigate therelative influences of primary and secondary particulateson total PM₁₀ levels at sites in the United Kingdom. Co-located PM₁₀ and sulphate aerosol measurementsindicate that sulphate has a disproportionately largeinfluence on the variation of PM₁₀ levels incomparison to its contribution to their total mass.Comparisons of measured PM₁₀ at urban centre, roadsideand rural sites suggest that local primary sources havevery little influence on daily mean levels. NAME has beenused to model both primary particles and sulphate aerosolfrom sources across the whole of Europe. The discrepanciesbetween modelled and observed PM₁₀ suggest that coarseparticles, such as windblown dust and resuspended roaddust,may comprise a very large, if not dominant, proportion ofobserved PM₁₀ levels. The apparently minor role ofprimary particles (especially locally-sourced ones) raisesa number of issues regarding the suitability of current U.K.and European legislation to addressing the particle problem.     

Hysteresis in Reversal of Central European Mountain Lakes from Atmospheric Acidification

Extremely high emissions of S and N compounds in Central Europe (both 280 mmol m^-2 yr^-1) declined by 70and 35%, respectively, during the last decade. Decreaseddeposition rates of SO₄ ^-2, NO₃ ^-, and NH₄ ⁺ in the region paralleled emission declines. The reduction in atmospheric inputs of S and N to mountain ecosystemshas resulted in a pronounced reversal of acidification in the Tatra Mountains and Bohemian Forest lakes. Between the 1987–1990and 1997–1999 periods, concentrations of SO₄ ^-2 and NO₃ ^- decreased (average ± standard deviation) by 22±7 and 12±7 mol L^-1, respectively, in theTatra Mountains, and by 19±7 and 15±10 mol L^-1, respectively, in the Bohemian Forest. Their decrease was compensated in part (1) by a decrease in Ca²⁺ + Mg²⁺ (17±7 mol L^-1) and H⁺ (4±6 mol L^-1), and an increase in HCO₃ ^-(10±10 mol L^-1) in the Tatra Mountains lakes, and (2) by a decrease in Al (7±4 mol L^-1), Ca²⁺ + Mg²⁺ (9±6 mol L^-1), and H⁺ (6±5 mol L^-1), in Bohemian Forest lakes. Despite the rapid decline in lake water concentrations of SO₄ ^-2 and NO₃ ^- in response to reduced S and N emissions, their present concentrations in some lakes are higher than predictionsbased on observed concentrations at comparable emission rates during development of acidification. This hysteresis in chemical reversal from acidification has delayed biological recovery of the lakes. The only unequivocal sign of biological recovery hasbeen observed in erné Lake (Bohemian Forest) where a cladoceran species Ceriodaphnia quadrangular has recentlyreached its pre-acidification abundance.     

Reconstruction of Long-Term Changes in Lake water Chemistry,Zooplankton and Benthos of a Small,Acidified High-Mountain Lake: Magic Modelling and Palaeolimnogical Analysis

Starolesnianske pleso is a small and shallow acid lake in the High Tatra Mountains, situated at 2000 m above sea level, on granitic bedrock, with sparse and thin soil cover. When detailed measurements began in the 1980s Starolesnianske pleso had pH below 5 and only one species of cladoceran zooplankton, the ubiquitous Chydorus sphaericusPalaeolimnological investigations show changes in cladoceran zooplankton and chironomid zoobenthic assemblages since about 1920 and a major change in 1970–1980. The dynamic acidification model MAGIC was used to reconstruct changes in water chemistry over the past 150 years. The results from MAGIC agree well with the sediment record; pH levels gradually decreased from 6.5 in the mid-1800s to about 5.6 in 1920 (first response in biota) to below 5.0 by 1970, and concentrations of inorganic aluminium rose dramatically beginning about 1960. In the 1990s the lake water chemistry showed clear signs of reversal in acidification brought about by a major decline in S deposition.     

Changes in Extractability of Cr and Pb in a Polycontaminated Soil After Bioaugmentation With Microbial Producers of Biosurfactants, Organic Acids and Siderophores

Partly because of the low bioavailability of metals, the soil cleaning-up using phytoremediation is usually time-consuming. In order to enhance the amount of metals at the plant's disposal, the soil bioaugmentation coupled together with phytoextraction is an emerging technology. In this preliminary work, two agricultural soils which mainly differed in their Cr, Hg and Pb contents (LC, low-contaminated soil; HC, high-contaminated soil) were bioaugmented in laboratory conditions by either bacterial (Bacillus subtilis, Pseudomonas aeruginosa, Pseudomonas fluorescens or Ralstonia metallidurans) or fungal inocula (Aspergillus niger or Penicillium simplicissimum) and incubated during three weeks. The LC soil pots bioaugmented with A. niger and P. aeruginosa contained higher concentrations of Cr (0.08 and 0.25 mg.kg⁻¹ dw soil) and Pb (0.25 and 0.3 mg.kg⁻¹ dw soil) in the exchangeable fraction F1 (extraction with MgCl₂) by comparison with the non-bioaugmented soil where neither Cr nor Pb was detected. Conversely, immobilization of Cr and Pb in the soil were observed with the other microorganisms. The soil bioaugmentation not only modified the metal speciation for the most easily extractable fractions but also modified the distribution of metals in the other fractions, to a lesser extent nevertheless. The difference in microbial concentrations between the bioaugmented or not HC soils reached up to 1.8 log units. Thus the microorganisms that we chose for the soil bioaugmentation were competitive towards the indigenous microflora. The PCA analysis showed close positive relationships between the microorganisms which potentially produced siderophores in the soil and the amount of Cr and Pb in the fraction F1.     

Heavy Metals Removal by Biosorption and Flotation

The removal of a mixture of heavy (toxic) metal cations (copper, nickeland zinc) from liquid effluents was investigated in this study at pilotscale, using counter-current contact mode. The innovative processinvolved the abstraction of metal ions onto fungal biosorbents, followedby the application of flotation for the subsequent solid/liquid separationof biomass particles. The ability of microorganisms to remove metal ionsfrom aqueous solutions is a well-known phenomenon. Nevertheless,engineering considerations are very important in decisions, concerningthe commercial future of biosorption and practical solutions are neededfor certain problems, such as the efficient post-separation ofmetal-loaded biomass. The two processes (flotation and biosorption) caneffectively operate in combination, in what it was termed biosorptiveflotation process. The sorbents may be recycled, after appropriate elutionof metals, as well as the treated (clean) water.     

酸浸出法回收冶金污泥中的有价金属

采用二次酸浸出的方法回收镍钴湿法冶金工业污泥中的有价金属。先采用水和硫酸作为浸出剂浸出Mg和Na,最佳工艺条件为浸出液的pH 7.5、浸出时间5 min、浸出剂体积与干污泥质量的比(ω)为10 mL/g。再采用硫酸作为浸出剂、焦亚硫酸钠作为还原剂进行二次酸浸,在硫酸与污泥质量比为1.3、焦亚硫酸钠与污泥质量比为0.3、ω为5 mL/g、浸出温度85℃、浸出时间20 min的最佳工艺条件下,Co、Ni、Cu、Mn和Zn的浸出率分别达92.45%、93.48%、89.52%、97.78%和94.79%。经XRD表征,浸出后污泥中未见原污泥中的矿物相,说明原污泥中的矿物几乎全部被溶解。     

不同原料生物炭对NH4+-N、PO43--P吸附性能的差异性及其成因分析

以芦苇、小麦秸秆和竹子为原料,利用回流式炭化工艺制备3种生物炭。比较三者对NH_4~+-N、PO_4~(3-)-P的吸附性能,并对三者吸附性能差异的成因进行分析。实验结果表明:3种生物炭对PO_4~(3-)-P的吸附效果整体上优于NH_4~+-N,因为3种生物炭的阳离子交换容量CEC值和Zeta电位绝对值的水平均较低,不利于阳离子的吸附;竹炭Z-C对NH_4~+-N的吸附效果最佳,6 h去除率为3.59%,低的N含量、pH及Zeta电位绝对值对NH_4~+-N的吸附有利;芦苇炭LW-C中的O更多地与K、Mg等结合,形成能够与PO_4~(3-)反应生成磷酸盐沉淀或者晶体物质的金属氧化物,从而具有最好的PO_4~(3-)-P的吸附效果,6 h时去除率达16.91%。