烟气脱硫溶液中硫酸根的去除

分别采用石灰乳化学沉淀法和低温结晶法去除烟气脱硫溶液中的SO42-。实验结果表明：在室温、CaO溶液质量分数25%的条件下,石灰乳化学沉淀法对SO42-的去除率仅为59.51%,且向溶液中引入了Ca2+,产生的硫酸钙固体废物难以再生利用;采用低温结晶法处理烟气脱硫溶液,在结晶温度7 ℃、结晶时间3 h、NaOH加入量34.8 g/L的条件下,SO42-的去除率为82.04%、滤液中的ρ（Na+）为3.88 g/L。在现场工业应用试验中,采用低温结晶法去除烟气脱硫溶液中的SO42-,平均SO42-的去除率可达70.00%以上,滤液中的ρ（Na+）小于15.00 g/L。该法可有效抑制烟气脱硫溶液中SO42-含量的增加。     

共代谢膜生物反应器法处理二甲基亚砜废水

采用蔗糖作为共代谢基质与一体式好氧膜生物反应器（MBR）工艺相结合处理二甲基亚砜（DMSO）废水。考察了装置的污泥驯化效果、DMSO去除率、污泥的性能、HRT和冲击负荷对DMSO去除率的影响。试验结果表明：驯化第29天,DMSO去除率达98.5%,表明MBR内的污泥已驯化成功;在MBR运行的正式期,当DMSO处于高负荷状态时,DMSO去除率较低;随蔗糖加入量的增加,DMSO去除率逐渐提高,最终恢复到DMSO高负荷冲击前的DMSO去除效果;正常运行时,装置进水ρ（DMSO）=257~1 448 mg/L（平均值为718 mg/L）、出水ρ（DMSO）=6~22 mg/L（平均值为7 mg/L）,DMSO去除率为96.4%~99.6%（平均值为98.9%）;在MBR运行的正式期,污泥体积指数小于100 mL/g,表明污泥的沉降性能较好,MLVSS/MLSS较高,表明污泥的活性高,MBR内MLSS的平均值为5.52 g/L,MLVSS的平均值为4.78 g/L;MBR适宜的HRT为12 h。     

活性污泥缺氧转化1-2-7-三氨基-8-羟基-3-6-萘二磺酸

1—2-7-三氨基-8-羟基-3—6-萘二磺酸（TAHNDS）作为偶氮染料的脱色产物很难被常规的厌氧-好氧染料废水处理工艺所去除。研究了未经驯化的活性污泥对TAHNDS的缺氧转化效果。结果表明,只有在特定的缺氧条件下（ORP在-50～-150mV之间）,TAHNDS才能被活性污泥所降解转化。当浓度在10—80mg／L范围内,TAHNDS可在72h内转化93％以上。加入100mg／L的硝酸盐和0．64mmol／L的氧化还原介体蒽醌-2-磺酸钠（AQS）可将40mg／L的TAHNDS的转化时间从84h缩短到36h。光谱及HPLC—MS分析表明,TAHNDS在缺氧条件下主要是通过脱氨基和脱磺酸作用生成已知可好氧生物降解的3,5-二氨基4-羟基萘-2-磺酸。因此,缺氧处理有望作为预处理工艺促进废水中TAHNDS的完全降解。     

林火烈度评价及其空间异质性研究进展

回顾了林火烈度评价的方法,包括单因素评价、综合评价和遥感技术的应用等;综述了林火烈度空间异质性的最新研究进展;展望了林火烈度及其空间异质性研究的未来发展趋势。     

Fate of bisphenol A during treatment with the litter-decomposing fungi Stropharia rugosoannulata and Stropharia coronilla

Bisphenol A is an endocrine disrupting compound, which is ubiquitous in the environment due to its wide use in plastic and resin production. Seven day old cultures of the litter-decomposing fungus Stropharia coronilla removed the estrogenic activity of bisphenol A (BPA) rapidly and enduringly. Treatment of BPA with purified neutral manganese peroxidase (MnP) from this fungus also resulted in 100% reduction of estrogenic activity, as analyzed using a bioluminescent yeast assay, and in the formation of polymeric compounds. In cultures of Stropharia rugosoannulata, estrogenic activity also quickly disappeared but temporarily re-emerged in the further course of cultivation. LC-MS analysis of the extracted estrogenic culture liquid revealed [M−H]⁻ ions with m/z values of 219 and 235. We hypothesize that these compounds are ring fission products of BPA, which still exhibit one intact hydroxyphenyl group to interact with estrogen receptors displayed by the yeast.     

The endocrine disrupting potential of sediments from the Upper Danube River (Germany) as revealed by in vitro bioassays and chemical analysis

Introduction  

The present study was part of a comprehensive weight-of-evidence approach with the goal of identifying potential causes for the declines in fish populations, which have been observed during the past decades in the Upper Danube River.     

Assessing the recovery potential of alpine moss-sedge heath: reciprocal transplants along a nitrogen deposition gradient

The potential of alpine moss-sedge heath to recover from elevated nitrogen (N) deposition was assessed by transplanting Racomitrium lanuginosum shoots and vegetation turfs between 10 elevated N deposition sites (8.2-32.9 kg ha⁻¹ yr⁻¹) and a low N deposition site, Ben Wyvis (7.2 kg ha⁻¹ yr⁻¹). After two years, tissue N of Racomitrium shoots transplanted from higher N sites to Ben Wyvis only partially equilibrated to reduced N deposition whereas reciprocal transplants almost matched the tissue N of indigenous moss. Unexpectedly, moss shoot growth was stimulated at higher N deposition sites. However, moss depth and biomass increased in turfs transplanted to Ben Wyvis, apparently due to slower shoot turnover (suggested to result partly from decreased tissue C:N slowing decomposition), whilst abundance of vascular species declined. Racomitrium heath has the potential to recover from the impacts of N deposition; however, this is constrained by the persistence of enhanced moss tissue N contents.     

基于MBR出水的纳滤预处理技术优化分析

针对再生水厂膜生物反应器(MBR)出水水质特征,对后续深度处理工艺中与纳滤组合的预处理技术进行筛选.通过对臭氧、活性炭、臭氧-活性炭3种预处理技术对比,分析3种预处理方式对有机物的去除效率及对分子尺寸的影响规律.实验结果表明,3种预处理技术对MBR出水中有机物的平均去除率分别为6.6%、31.7%和36.6%;市政污水...     

污染防治微生物制剂在城市河流污染控制中的应用及其生物安全

简要论述了污染防治微生物制剂的概念和在城市河流污染控制中的应用,并介绍了国外对微生物制剂的风险评估和对污染防治微生物制剂的管理方式,提出了国内应优先开发本土的天然的污染防治微生物制剂的建议,尽快发展中国环境微生物技术.     

Measurement of gas-phase total peroxides at the summit of Mount Tai in China

Measurement of ambient gas-phase total peroxides was performed at the summit of Mount Tai (Mt. Tai, 1534 m above sea level) in central-eastern China during March 22–April 24 and June 16–July 20, 2007. The hourly averaged concentration of peroxides was 0.17 ppbv (± 0.16 ppbv, maximum: 1.28 ppbv) and 0.55 ppbv (± 0.67 ppbv, maximum: 3.55 ppbv) in the spring and summer campaigns, respectively. The average concentration of peroxides at Mt. Tai, which is in a heavily polluted region, was much lower than hydrogen peroxide measurements made at some rural mountain sites, suggesting that significant removal processes took place in this region. An examination of diurnal variation and a correlation analysis suggest that these removal processes could include chemical suppression of peroxide production due to the scavenging of peroxy and hydroxy radicals by high NO_x, wet removal by clouds/fogs rich in dissolved sulfur dioxide which reacts quickly with peroxides, and photolysis. These sinks competed with photochemical sources of peroxides, resulting in different mean concentrations and diurnal pattern of peroxides in the spring and summer. A principal component analysis was conducted to quantify the major processes that influenced the variation of peroxide concentrations. This analysis shows that in the spring photochemical production was an important source of peroxides, and the major sink was scavenging during upslope transport of polluted and humid air from the lower part of the planetary boundary layer (PBL) and wet removal by synoptic scale clouds. During the summer, highly polluted PBL air (with high NO_x) was often associated with very low peroxides due to the chemical suppression of HO₂ by high NO_x and wet-removal by clouds/fogs in this sulfur-rich atmosphere, especially during the daytime. Higher concentrations of peroxides, which often appeared at mid-nighttime, were mainly associated with subsidence of air masses containing relatively lower concentrations of NO_y.