Zn(Ⅱ)对生物质碳源处理酸性矿山排水中厌氧微生物活性影响

通过厌氧批实验的方法,探讨了在硫酸盐还原菌(SRB)法处理模拟酸性矿山排水(AMD)的过程中,以油菜秸秆为碳源时,Zn2+浓度对SRB活性的影响.结果表明,在60 d实验中,以油菜秸秆为碳源时,当Zn2+初始浓度在73.7～196.8 mg.L-1范围时,SRB具有良好活性,实验结束时,pH从初始的5.0上升至中性范围,硫酸根还原率达到96%以上,同时Zn2+浓度降至0.05 mg.L-1以下.Tessier固体形态分类、场发射扫描电镜(FE-SEM)和X射线衍射仪(XRD)分析发现,Zn以有机物及硫化物的形态被固定,其中硫化物主要为闪锌矿(ZnS).当Zn2+初始浓度为262.97 mg.L-1时,SRB的活性受到强烈的抑制,实验结束时,pH从初始的5.0降至4.0左右,硫酸根还原率只有27%,Zn2+维持在较高浓度范围(25 mg.L-1).油菜秸秆可以作为SRB法长期处理AMD的缓释碳源,能为微生物生长繁殖提供物质和能量;秸秆的吸附性可降低Zn2+的生物毒性,使得SRB可以适应高浓度的Zn2+;SRB可以通过形成硫化物矿物的形式固定元素Zn.     

Bayesian estimation of European sulphur emissions using monitoring data and an acid deposition model

A statistical method for estimating national emissions of acidifying air pollutants in Europe is presented. The method uses an acid deposition model to match official emissions data from European countries and measured depositions from a monitoring network. An application to 1990 sulphate data demonstrates the method and suggests some tendencies in the reported emissions. The proposed framework may prove useful for verifying national compliance with emissions standards, and the method should be applicable also to other substances than sulphur dioxide. The problem of designing an optimal monitoring network may also be assessed within the proposed statistical framework.     

对苯二酚生产中含硫酸锰废水的综合利用

根据硫酸锰废水的特性,采用中和除铁和硫化除钴、镍等方法先使废水净化,得到合格电解液.其后对该电解液通电并加入硒电解24小时,再经钝化等处理制得金属锰.利用电解硫酸锰后的阳极废水制取碳酸锰,并从碳酸锰废水中回收硫酸铵.本工艺简单可行,产品金属锰纯度达99.8％以上,经济和环境效益显著.     

铁盐和铝盐混凝剂对消毒副产物的控制作用及机制研究

以三氯化铁和硫酸铝为研究对象,探讨了两种混凝剂对三氯甲烷生成量的控制作用及控制机制．结果表明,与硫酸铝相比,三氯化铁可以更好地控制三氯甲烷的生成量,对有机物的去除方面,也具有良好的效果．E4／E6变化表明,三氯化铁和硫酸铝对水中有机物的去除机制不同,硫酸铝主要去除水中大分子的有机物,三氯化铁更倾向于去除水中小分子有机物,而这些小分子有机物通常是消毒副产物的前体物,从而使三氯化铁对消毒副产物的控制作用较硫酸铝明显．     

铜铬氧化物废催化剂中铜铬的回收

以糠醛加氢制糠醇用的废铜铬氧化物催化剂为原料,通过焙烧、酸化、过滤、重结晶制取硫酸铜,再将所得沉淀加纯碱,焙烧,浸取,制取铬矾。该方法工艺简单、成本低且可同时回收铜铬两种离子．铜离子回收率92％,铬离子回收率达60％以上。     

KOH等度淋洗IC法同时测定自来水中微量ClO2-、ClO3-及常规阴离子

建立了KOH等度淋洗离子色谱法同时测定自来水中微量亚氯酸盐、氯酸盐及氟化物、氯化物、硝酸盐、硫酸盐的分析方法。该方法以20.5 mmol/L KOH为淋洗液,流速1.0 mL/min,进样量50μL。结果表明,6种阴离子可在12分钟内检测完毕,各离子的线性相关系数为0.997 0~0.999 9;检出限为0.05~7.00μg/L;精密度为0.61%~3.82%;回收率为97.6%~101.7%,能够满足饮用水中这些指标的定量需要,是一种灵敏、准确、快速的理想方法。     

溶液中阴离子和腐殖酸对UV/H2O2降解2,4-二氯酚的影响

研究了UV/H2O2工艺对2,4-二氯酚(2,4-DCP)的去除效果和水中阴离子、腐殖酸对该工艺降解2,4-DCP的影响.结果表明:UV/H2O2工艺可以有效地去除水中2,4-DCP,光降解过程符合一级反应动力学模型;在H2O2投加量为8 mg/L、1个30 W低压汞灯照射下,2,4-DCP在蒸馏水和自来水中反应速率常数分别为0.023 2、0.016 2 min-1;NO-3、Cl-、HCO-3对2,4-DCP光降解有抑制作用,当3种阴离子摩尔浓度为0.5、10.0、20.0 mmol/L时,对2,4-DCP光降解的抑制程度为HCO-3＞NO-3＞Cl-;腐殖酸在低浓度时,促进光降解反应进行,在高浓度时,2,4-DCP的光降解受到抑制.自来水中的反应速率常数低于蒸馏水中的反应速率常数是由于水中多种阴离子和腐殖酸影响的结果.     

金属铁去除水中Cr~（6＋）的影响因素研究

研究Fe/Cr6＋比值和不同浓度的NO3-、Cl-和SO42-对金属铁去除Cr6＋效果的影响。结果表明,金属铁对水中Cr6＋有很好的还原去除效果;当金属铁的使用量为Cr6＋量的1/2 000时,铁对Cr6＋的去除效果较差且易失去活性,而当金属铁的使用量为Cr6＋量的8 000倍时,铁对Cr6＋的去除效果较好且其活性的持续性较强;3种阴离子（NO3-、Cl-和SO42-）均能提高金属铁对重金属Cr6＋去除率,但在反应初期,3种阴离子对金属铁去除水中Cr6＋影响的差异性不显著,随着反应时间的增加,SO24-对金属铁去除水中Cr6＋的促进作用逐渐强于Cl-和NO3-,3种阴离子对金属铁去除Cr6＋效率促进作用的大小顺序为SO24-〉Cl-〉NO3-。     

Analysis of Long-term Measurements of Airborne Concentrations of Sulphur Dioxide and SO42- in the Rural United Kingdom

During the last two decades, the importance of sulphur dioxide as a pollutant has moved away from its association with suspended particulate matter, to it being a precursor of SO ₄ ^2- aerosol (acidic e.g. sulphuric acid, or neutralised e.g. ammonium sulphate). Co-located concentration data of sulphur dioxide and SO ₄ ^2- , at nine monitoring sites situated in predominantly rural areas in the United Kingdom, collected over the time period 1979–1995, have been analysed. The time series for both species are discussed for the sites. Further analysis has shown that there is a degree of correlation between sulphur dioxide and SO ₄ ^2- for most of the sites considered. This correlation is of approximately the same level for most of the sites taken independently and together, and in most cases the slopes and intercepts associated with the simple empirical model equations arising from the correlation analysis, are of the same order of magnitude. The implementation of these site-dependent model equations within dispersion models for the prediction of the concentration of airborne sulphate aerosol from knowledge of sulphur dioxide concentration is discussed. Furthermore, the correlation analysis revealed the influence of transported sulphate aerosol on the local concentration, especially during high concentration episodes.     

Surface Water Seepage Effects on Shallow Ground‐Water Quality Along the Rio Grande in Northern New Mexico1

Abstract: Interactions between surface irrigation water, shallow ground water, and river water may have effects on water quality that are important for both drinking water supplies and the ecological function of rivers and floodplains. We investigated water quality in surface water and ground water, and how water quality is influenced by surface water inputs from an unlined irrigation system in the Alcalde Valley of the Rio Grande in northern New Mexico. From August 2005 to July 2006, we sampled ground water and surface water monthly and analyzed for concentrations of major cations and anions, specific conductance, pH, dissolved oxygen, and water levels. Results indicate that irrigation ditch seepage caused an increase in ground water levels and that the Rio Grande is a gaining stream in this region. Temporal and spatial differences were found in ion concentrations in shallow ground water as it flowed from under the ditch toward the river. Ground‐water ion concentrations were higher when the ditch was not flowing compared with periods during peak irrigation season when the ditch was flowing. Ditch inputs diluted ion concentrations in shallow ground water at well positions near the ditch. Specifically, lower ion concentrations were detected in ground water at well positions located near the ditch and river compared with well positions located in the middle of an agricultural field. Results from this project showed that ditch inputs influenced ion concentrations and were associated with ground‐water recharge. In arid region river valleys, careful consideration should be given to management scenarios that change seepage from irrigation systems, because in some situations reduced seepage could negatively affect ground‐water recharge and water quality.