油脂废水的生物处理研究进展

餐饮业废水的大量增加,对环境造成的污染日趋严重,给人民生活带来一系列的影响。常用的餐饮废水处理方法有物理法、化学法、生物法,生物法因具有成本低,不需特殊设备,不会带来二次污染等优点,近年来逐渐成为国内外餐饮业废水的主要处理方法。文章对国内外餐饮废水生物处理方法的特点和机理进行了综述,并对未来的发展提出了展望。     

快速生物活性测定方法的仪器化

好氧活性污泥法在污水处理中应用广泛.保持污泥活性,是良好处理效果的前提,也是运行控制的主要目标.活性污泥的呼吸速率,或者氧利用速率(oxygen uptake rate,OUR),能够指示污泥的活性变化.本研究开发的快速生物活性测定仪(rapid biological activity tester,RBAT),能够快速测定污泥活性参数,满足工程设计与运行的迫切要求.     

污水厂生物除臭设施运行及影响因素的研究

在污水处理过程中会有大量的恶臭气体产生,主要含硫化氢和氨等发臭物质.这些臭味物质逸散到空气中,对污水处理厂及其周边的空气环境造成危害.针对清河污水处理厂原有生物除臭设施除臭效率难以提高的问题,对气体收集系统和生物除臭滤池内的喷淋管路进行了改造,并更换了新型生物填料.本研究对改造前后的除臭效果进行了考察,结果显示,硫化氢的平均去除率从改造前的36.5%提高到62.9%,最大去除率可以达到96.2%;氨的去除率从28.2%提高到接近100%.臭味气体的处理效果随除臭滤池的温度、气体的相对湿度的升高而提高.为此,对臭味气体的负荷、流量、温度以及湿度等因素进行了研究,在温度＞20℃、相对湿度＞80%的条件下,生物除臭滤池能够有比较理想的处理效果.     

新型侧向流曝气生物滤池处理生活污水

采用以沸石为填料的新型侧向流曝气生物滤池处理生活污水,考察了水力负荷和气水比的影响.结果表明,LBAF在最佳工况气水比10∶1,A、B段曝气量比1∶1,水力负荷0.43 m3/m2·h下,COD、SS、氨氮、总氮和总磷的去除率分别为88.01%、95.18%、78.97%、52.58%和21.02%;COD去除率随COD容积负荷的增加缓慢下降.氨氮、总氮去除率随COD容积负荷的增大明显下降,氨氮去除率随氨氮容积负荷的增大而明显降低.滤池纳污能力强,不易堵塞,可适当延长反冲周期.     

卤代酚复合污染对鲤科金鱼的生化毒性效应研究

为探讨卤代酚复合污染对水生生物的联合毒性效应,探究较为可靠的检测方法,根据所选6种卤代酚化学结构的相似程度和48 h LC₅₀值,将其分为3组二元混合物进行急性暴露实验, 毒性单位比为1∶1,每组分2个浓度级别观察金鱼生物学行为的变化,同时检测金鱼肝脏中3种抗氧化酶(SOD,CAT和GSH-Px)活性以及酶活性影响率的变化. 结果表明:3组卤代酚对金鱼肝脏中3种抗氧化酶的酶活性影响率变化均有显著性差异(P<0.01);3种抗氧化酶中仅SOD在1/2LC₅₀剂量暴露组中均表现为明显升高的酶活性激活率或酶活性抑制率,提示SOD较适合作为卤代酚低浓度复合水污染情况监测的生物化学检测指标.      

优势菌群在复合生态床修复景观水体中的强化能力研究

以沸石和煤渣为主要基质构建复合生态床修复景观水体,并筛选驯化优势菌群对修复进行生物强化,以原始土著生物群强化和无生物强化为对比.结果表明,随停留时间延长,土著生物强化与优势菌群强化对NH⁺₄-N、 TN和TP的去除率增加.自然基质系统对NH⁺₄-N去除率最高,其次是优势菌群强化系统;优势菌群对TN的去除率最高,且随停留时间延长有明显提高;原始土著生物强化系统对TP去除率最高.NO^-₂-N延程浓度在自然基质系统中始终最低,优势菌群强化过程中低于土著生物;优势菌群强化延程TN浓度一直减小;原始土著生物强化延程对TP的去除始终强于优势菌群,强于自然基质.优势菌群中大量氨氧化菌和亚硝酸氧化菌的存在,使基质中硝化作用进行迅速而且彻底,减少了中间产物的积累,促进了不同形态氮的生物去除.优势菌群长时间在系统内保持较高活性,强化对含氮污染物的硝化去除.聚磷菌提高系统对P的去除,多种生物群的协同作用使系统除磷能力进一步增强.     

DEVELOPMENT OF AN INVERTEBRATE COMMUNITY INDEX FOR AN ALABAMA COASTAL PLAIN WATERSHED1

ABSTRACT: Activities such as agriculture, silviculture, and mining contribute nonpoint pollution to Alabama's streams through polluted runoff and excessive sedimentation. Highly erodible soils characteristic of the Choctawhatchee‐Pea Rivers watershed, combined with intense rainfall and land use practices, contribute large amounts of sediment to streams. Biological monitoring can reflect the acute impacts of pollutants as well as prolonged effects of habitat alteration, and development of biological criteria is important for the establishment of enforceable laws regarding nonpoint source pollution. Macroinvertebrates were collected from 49 randomly selected sites from first through sixth‐order streams in the Choctawhatchee‐Pea Rivers watershed and were identified to genus level. Thirty‐eight candidate metrics were examined, and an invertebrate community index (ICI) was calibrated by eliminating metrics that failed to separate impaired from unimpaired streams. Each site was scored with those metrics, and narrative scores were assigned based on ICI scores. Least impacted sites scored significantly lower than sites impacted by row crop agriculture, cattle, and urban land uses. Conditions in the watershed suggest that the entire area has experienced degradation through past and current land use practices. An initial validation of the index was performed and is described. Additional evaluations of the index are in progress.     

Microscale Spatial Variation in Forest Litter Phytotoxicity

The spatial variation (within a 100 × 100 m plot) in the pollution of forest litter with heavy metals (Cu, Cd, Pb, and Zn), its acidity, and phytotoxicity (measured by the results of the root test using seedlings from a genetically homogeneous sample of common dandelion (Taraxacum officinale s.l.) have been estimated. Forest litter has been sampled in three zones differing in the toxic impact of long-term polymetal pollution by emissions from a copper-smelting plant emissions in the Middle Urals. The phytotoxicity variation is maximum in a moderately polluted plot, where both very high and very low pollution levels were observed, which determines a substantially nonlinear dose–effect relationship. The litter phytotoxicity is mainly accounted for by exchangeable forms of metals. Biological testing of samples from the most polluted plot has demonstrated marked antagonism between heavy metals and acidity.     

内蒙古生态建设状况综合评价与分析

依据国家林业局提出的评估生态建设状况的量化方法,结合内蒙古生态建设的现状,选取了森林、荒漠、水土流失、生物多样性、湿地、草原、农田、城市生态状况等8项指标来判断内蒙古的生态建设状况.在运用专家打分法和生态综合指数评价模型确定各指标权重和计算其生态综合指数的基础上,对自治区近5 a的生态建设状况进行了综合评价与分析.内蒙古生态综合指数经计算为1.05,表明自治区的生态建设形势和全国一样,处于生态治理与生态破坏的相持阶段,且其判断指标大多处于相持状态,有的已处于治理大于破坏阶段.