错流式动态膜-生物反应器中污泥活性的研究

应用错流式动态膜-生物反应器(CDMBR)对己内酰胺废水进行了180 d的实验,实验过程中测定反应器的膜出水和上清液的水质,并对污泥进行了耗氧呼吸速率测定.结果表明,上清液COD一直保持在100mg/L以下,而膜出水的则保持在50 mg/L以下,膜对上清液的COD去除率达50%,而对氮的去除没有贡献.可溶性细胞产物(SMP)在反应器内容易积累,停留足够的时间后能被生物降解.通过投加抑制剂测定耗氧呼吸速率,发现异养菌、硝化细菌和亚硝化细菌的活性由于F/M的降低和SMP积累受到一定的抑制,但不影响系统的处理效率.跨膜压力、膜面流速越大,通量衰减得也就越快.     

温度对复合厌氧折流板膜生物反应器处理生活污水效能的影响

将新型CAMBR反应器（厌氧折流板反应器（ABR）与膜生物反应器（MBR）优化组合）用于处理生活污水,研究温度对该反应器处理效能的影响。实验水力停留时间7．5h,混合液回流比设置为200％,pH值为6．5～8．5,溶解氧3mg／L左右。控制3个温度梯度：高温（32～37％）,中温（20～25℃）,低温（5～10％）,每个温度运行35d。结果表明,在高温条件下,系统出水COD、NH4．N、TN和TP平均浓度分别为25、0．5、12．5和0．7mg／L。在中温条件下,系统出水COD、NH4＋-N、TN和TP浓度分别30、1．2、12．5和0．4mg／L。在低温条件下,COD和TP分别经过15d和20d调整适应,出水可恢复至35mg／L和1mg／L。由于低温（10％以下）对硝化细菌产生强烈抑制,出水NH4＋-N去除率最终稳定在35％,TN去除率为40％。低温条件下,该反应器应用于污水处理中需注意适当保温,以保证出水水质。     

一体式膜生物反应器处理生活污水的中试研究

采用中试规模（1.8m^3／d）的缺氧-好氧膜生物反应器（A／OMBR）对城市污水处理回用进行了试验研究。试验结果表明，该工艺处理效果优良，系统对COD、氨氮、浊度、总氮、总磷去除率较高，COD、氨氮出水浓度分别为7～39 mg/L、0～1.31mg／L。出水水质优于城市杂用水水质标准（GB／T18920-2002）。     

温度对复合厌氧折流板膜生物反应器处理生活污水效能的影响简

将新型CAMBR反应器（厌氧折流板反应器（ABR）与膜生物反应器（MBR）优化组合）用于处理生活污水,研究温度对该反应器处理效能的影响。实验水力停留时间7.5 h,混合液回流比设置为200%,pH值为6.5~8.5,溶解氧3 mg/L左右。控制3个温度梯度：高温（32~37℃）,中温（20~25℃）,低温（5~10℃）,每个温度运行35 d。结果表明,在高温条件下,系统出水COD、NH₄⁺-N、TN和TP平均浓度分别为25、0.5、12.5和0.7 mg/L。在中温条件下,系统出水COD、NH₄⁺-N、TN和TP浓度分别30、1.2、12.5和0.4 mg/L。在低温条件下,COD和TP分别经过15 d和20 d调整适应,出水可恢复至35 mg/L和1 mg/L。由于低温（10℃以下）对硝化细菌产生强烈抑制,出水NH₄⁺-N去除率最终稳定在35%,TN去除率为40%。低温条件下,该反应器应用于污水处理中需注意适当保温,以保证出水水质。     

中试螺旋式自循环厌氧反应器处理安乃近制药废水的稳定性能

以制药废水实验了50m3螺旋式厌氧反应器（SPAC反应器）的稳定性。采用AugmentedDickey—Fuller（ADF）单位根检验表明,螺旋式反应器具有良好的启动和运行稳定性。负荷冲击实验显示,SPAC反应器具有较好的耐浓度冲击能力和耐水力冲击能力,所能耐受的最大浓度冲击强度大于60000（mg·h）／L（进水浓度提升2倍）,所能耐受的最大水力冲击强度为300（m3·h）／d（进水流量提升50％）。SPAC反应器还具备受扰恢复能力。在反应液pH低于5．74,出水浓度、COD去除率和容积COD去除速率（VRR）分别为3500mg／L、22．30％和2．52kg／（m3·d）的工况下,经过30d恢复,出水浓度、COD去除率和VRR的恢复程度达到80％～90％。     

吸附-预沉淀MBR工艺处理生活污水及膜污染控制效果

膜污染是限制膜生物反应器（MBR）广泛应用的主要因素之一。针对MBR处理生活污水过程中存在的硝化效果不稳定与膜污染问题,提出了一种新型的MBR系统：通过吸附-预沉淀实现进水中碳氮的分离和单独处理,不仅提高了污染物去除效果,且能够有效控制膜污染。研究结果表明,吸附-预沉淀可以去除进水中约89.7%的有机物,系统出水COD、NH₄⁺-N平均浓度为24 mg/L、0.78 mg/L,去除率分别为95.9%和98.1%。MBR中碳氮比的降低和硝化细菌比例的增加大大降低了MBR内MLSS、EPS和SMP含量,平均浓度分别为5 185 mg/L、41 mg/g MLSS和2.62 mg/g MLSS。在膜通量为4 L/（m²·h）条件下,TMP可稳定保持在20 kPa左右。通过吸附-预沉淀过程可有效控制MBR中的膜污染。     

MBR处理低浓度稠油废水

为解决稠油废水达标排放问题,构建了一套中试实验装置,以经过除油、浮选和过滤预处理的富含溶解性有机化合物、氮磷缺乏的低浓度难生化稠油废水为原水,进行了187 d的连续运行,结果表明,经过厌氧和好氧生物处理后,出水COD可降至80~100 mg/L以下,再经膜过滤后COD降至60~80 mg/L,加入少量的粉末活性炭进行吸附处理后,出水COD可稳定在50 mg/L以下;水力停留时间从72 h降至30 h时,出水COD基本无变化;气相色谱-质谱分析表明该系统容易去除的有机物为酮类、醇类等物质,而烷烃(C17~C25)和芳烃等为本工艺难降解物质,通过膜生物反应器工艺优化或选择专门降解菌如Acinetobacter spp.进行处理可进一步降低出水COD的浓度。     

螺旋升流式反应器脱氮除磷系统的运行效果与污泥性能分析

对螺旋升流式反应器脱氮除磷及去除COD的运行效果进行了研究，该系统连续稳定运行6个月的结果表明．能保证出水平均质量浓度TN小于10mg／L，TP小于0．50mg／L，COD小于31mg／L，对TN、TP和COD的去除率分别达86％、96％和94％以上。并且对SUFR系统的污泥性能进行了分析：(1)螺旋升流特征使本反应系统中的污泥易于颗粒化；(2)SUFR系统中的微生物种群具有多样性；(3)污泥在好氧反应器中表现出了同步硝化反硝化功能；(4)污泥在缺氧反应器表现出了反硝化吸磷现象。     

厌氧-好氧工艺处理制药废水的中试研究

将由厌氧折流板反应器(ABR)、移动床生物膜反应器(MBBR)和膜生物反应器(MBR)组合而成的厌氧-好氧工艺用于处理制药废水的中试研究.试验结果表明,当原水SS平均值为1000 mg/L,COD为10 000 mg/L,NH3-N为500 mg/L时,出水浊度、COD和NH3-N分别为3 NTU、500 mg/L以及10 mg/L以下,去除率分别为98%、95%和98%以上.     

采用HSB菌种生化处理焦化废水

采用HSB微生物菌种技术和缺氧-好氧（O-O／A工艺）组合工艺处理焦化废水的研究,结果表明,该技术处理焦化废水有很好的效果,COD从2500mg／L左右降至130mg／L以下,去除率达94．8％以上;NH3-N从500mg／L降至15mg／L以下,去除率达97％以上;出水COD、氨氮、酚、氰、油等污染物均可达《污水综合排放标准》（GB8987--1996）二级标准。     

Chloroaromatic pollutants in mussels incubated in two finnish watercourses polluted by industry

Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.     

Book review

The Pesticide Manual ‐ A World Compendium, 8th Edition, C.R. Worthing, Editor and S.B. Walker, Assistant Editor, British Crop Protection Council, BCPC Publications Sales, Bear Farm, Binfield, Bracknell, Berkshire RG12 5QE, England. 1987, 1100 pp., UK £50; Overseas £56. ISBN 0–948404–01–9.     

Organochlorine compounds in a three-step terrestrial food chain

The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.     

The chemical stability of formulations of some hydrolyzable insecticides in aqueous mixtures with hydrolysis catalysts

Abstract

The active ingredients in commercial formulations of malathion, oxamyl, carbaryl, diazinon, and chlorpyrifos diluted to “spray tank”; concentrations with buffered distilled or natural water of pH 4–9 were stable for at least 24 hr. Formulations of trichlorfon were not stable at pH 7 or above but disappearance rates were slower than for the pure chemical in homogeneous solution. Cupric ion was observed to be an effective catalyst for the hydrolysis of a variety of pure organophosphorus insecticides but did not catalyze hydrolysis of the active ingredients of the formulations examined. Increasing the dilution of the formulation increased the susceptibility of malathion, oxamyl, and carbaryl to hydrolysis.     

Radionuclides in pinon pine (Pinus edulis) nuts from los alamos national laboratory lands and the dose from consumption

Abstract

One of the dominant tree species growing within and around the eastern portion of Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis). Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food—the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of ³H, ¹³⁷Cs, ⁹⁰Sr, ^totU, ²³⁸Pu, ^{239, 240}Pu, and²⁴¹ Am in soils (0‐ to 12‐in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (3) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of ³H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 lb [4.5 kg]) was 0.0018 mrem (0.018 μSv); this is far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem (1000 μSv). Soil‐to‐nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables.     

Degradation and sorption of imidacloprid in dissimilar surface and subsurface soils

Degradation and sorption/desorption are important processes affecting the leaching of pesticides through soil. This research characterized the degradation and sorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine) in Drummer (silty clay loam) and Exeter (sandy loam) surface soils and their corresponding subsurface soils using sequential extraction methods over 400 days. By the end of the incubation, approximately 55% of imidacloprid applied at a rate of 1.0 mg kg^?1 degraded in the Exeter sandy loam surface and subsurface soils, compared to 40% of applied imidacloprid within 300 days in Drummer surface and subsurface soils. At the 0.1 mg kg^?1 application rate, dissipation was slower for all four soils. Water-extractable imidacloprid in Exeter surface soil decreased from 98% of applied at day 1 to > 70% of the imidacloprid remaining after 400 d, as compared to 55% in the Drummer surface soil at day 1 and 12% at day 400. These data suggest that imidacloprid was bioavailable to degrading soil microorganisms and sorption/desorption was not the limiting factor for biodegradation. In subsurface soils > 40% of ¹⁴C-benzoic acid was mineralized over 21 days, demonstrating an active microbial community. In contrast, cumulative ¹⁴CO₂ was less than 1.5% of applied ¹⁴C-imidacloprid in all soils over 400 d. Qualitative differences in the microbial communities appear to limit the degradation of imidacloprid in the subsurface soils.     

Biochemical interaction of six op delayed neurotoxicants with several neurotargets

Abstract

Five organophosphorous insecticides: Leptophos, EPN, Cyano‐fenphos, trichloronate and salithion proved to cause irreversible ataxia not only to chicken but also to mice and sheep. TOCP was included as a reference. Cyanofenphos blocked the catecholamine B‐receptor binding activity with ³H‐norepinephrine at a level similar to that of the specific inhibitor propranolol in the mouse heart preparation. In the lamb heart preparation, the B‐receptor was more sensitive to Leptophos, salithion and TOCP than to propranolol. The six compounds and their oxons were screened for their in‐vitro inhibition to monamine oxidase (MAO), acetyl cholinesterase (AChE) and neurotoxic esterase (NTE) in the brain of either mouse, lamb or chicken. It is believed that their AChE inhibition stands for their acute toxicity, while NTE inhibition is responsible for their paralytic ataxia.     

土壤中砷的化学平衡

本文比较详细地综述了砷的化学特性,环境背景值及来源和循环,土壤中砷的三大化学平衡即沉淀溶解平衡,氧化还原平衡,吸附解吸平衡,以及微生物对砷的转化。     

Elemental uptake by edible herbs and lettuce (Latuca sativa)

The total concentration of toxic elements (aluminum, cadmium, chromium and lead) and selected macro and micro elements (iron, manganese, copper and zinc) are reported in six leafy edible vegetation species, namely lettuce, spinach, cabbage, chards and green and red types of Amaranth herbs. Although spinach and chards had greater than 125 mv of iron, both the amaranthus herbs recorded > than 320 μ g g^{? 1} dry weight. In both the spinach and chard species, the Mn and Zn levels were appreciable recording > 225 μ g g^{? 1} and 150 μ g g^{? 1} dry weight, respectively. Aluminum concentrations were (in μ g g^{? 1} dry weight) lettuce (10), cabbage (11), spinach (167), chards (65), amaranthus green (293) and amaranthus red (233). All the micro and macro elements and the toxic elements (Ni, Cr, Cd and Pb) elements analyzed, were below the recommended maximum permitted levels (RMI) in vegetables. Further the elemental uptake and distribution of the nine elements, at three growth stages of the lettuce plant grown on soil bed under controlled conditions are detailed. In the soil, except for iron (16%), greater than 33% of the other cations were in exchangeable form. Generally in the lettuce plant, roots retained much of the iron (> 224 μ g g^{? 1}) and aluminum (> 360 μ g g^{? 1}), while leaves had less than 200 μ g g^{? 1} of iron and 165 μ g g^{? 1} of Al. Although the concentrations of elements marginally decreased with growth, the lettuce leaves had significant amounts of Mn (30 μ g g^{? 1}), Zn (50 μ g g^{? 1}) and Cu (3.6 μ g g^{? 1}). Some presence of lead in leaves (2.0 μ g g^{? 1}) was noticed, but all the toxic and other elements analyzed were well below the RMI values for the vegetables.     

The dissipation of nonlyphenol in stream and pond water under simulated field conditions

Abstract

The dissipation of 1.0 ppm nonylphenol in stream and pond water, incubated in flasks at 16°C under simulated field conditions up to 44 days indicated that the half‐life was 2.5 days if the flasks were open, and 16 days if they were closed. A transformed product was detected in the closed flasks.

Translocation of nonylphenol in water occurred when treated water samples were incubated in the presence of sediment. After 10 days, nonylphenol was detected only in the sediment, but not in water (detection limit = 10 ppb). About 80% of the nonylphenol was degraded in 71 days, but no degradation occurred if the water and the sediment were autoclaved prior to incubation.