加压生物接触氧化法处理增塑剂生产废水试验研究

主要介绍了采用加压生物接触氧化法处理增塑剂废水。在停留时间为２２ｈ，压力为０．４ＭＰａ，水中溶解氧保持５ｍｇ／Ｌ左右时，进水ＣＯＤＣＲ为１１７００ｍｇ／Ｌ，ＢＯＤ５为６８７３ｍｇ／Ｌ，出水ＣＯＤＣｒ去除率为８９％，ＢＯＤ５去除率为９６％。为增塑剂废水治理工程设计提供了重要参数。     

SBR法处理医药有机废水工艺研究

医药有机废水中ＣＯＤｃＲ２０００－３０００ＭＧ／ｌ，ｂｏｄ５３００－５００ＭＧ／ｌ，ｐＨ为４－５左右，采用ＳＢＲ法处理后，ＣＯＤｃｒ去除率大于８５％，ＢＯＤ５去除率大于９０％，ｐＨ６－９。为废水后续处理达标奠定了良好的基础。     

兼氧接触工艺处理造纸中段废水中间试验的研究

采用中试规律的兼氧接触工艺处理造纸中段废水，当处理水量为４．８ｍ＾３／ｄ，水力停留时间３～４ｈ，气水比３：１，进水ＰＨ８～９．５，平均ＣＯＤ浓度为１６４１．６ｍｇ／ｌ，ＢＯＤ５５１６．１ｍｇ／ｌ，ＳＳ６８８．４ｍｇ／ｌ的条件下，处理后出水ｐＨ７．５左右，平均ＣＯＤ浓度为１０５９．８ｍｇ／ｌ，去除率３４．９％，ＢＯＤ５２４６．５ｍｇ／ｌ，去除率５２．１％，ＳＳ１６１．９ｍｇ／ｌ，去除率为７７．１％。     

厌氧—好氧法处理渗滤液与城市污水混合废水的可行性

彩厌氧－好氧工艺对不同浓度的垃圾填埋场渗滤液与城市污水在不同混合比（ＶＳＨ：ＶＣＨ）时的处理效果及可行性进行了研究,厌氧段采用新型ＡＢＲ反应器并将控制在水解酸化阶段。研究表明,当原渗滤液ＣＯＤ〈５５００ｍｇ／Ｌ时,ＶＳＨ：ＶＣＨ达４：６是可行的,其稳定运行时的ＣＯＤ和ＢＯＤ５去除率可分别达８８．９％和９６．８％当原渗滤液ＣＯＤ≥６５００～８８００ｍｇ／Ｌ时,须将ＶＳＨ：ＶＣＨ控制在２．８以内。     

养猪场废水处理工艺研究

采用接触氧化－水解－两段接触氧化－混凝工艺处理高浓度养殖废水,通过试验得到最佳工艺参数,在最佳试验条件下,进水ＣＯＤｃｒ小于５０００ｍｇ／Ｌ,经处理后出水ＣＯＤｃｒ平均去地９７％,ＢＯＤ５去除率大于９８％,氨氮去除率大于９６％,各项主要指标可达污水综合排放标准一级标准。     

利福平废水的絮凝和生化处理研究

种福平生产的废水ＣＯＤ高达６万,用ＰＦＳ、Ｃ－ＰＡＭ脱稳,密集网捕式絮凝处理后,ＣＯＤ去除率达２７％,ＢＯＤ５／ＣＯＤｃｒ从０．１９上升到０．３２,絮凝前后水质和色谱分析表明,絮凝后５种有机物去除效率均在２２％以上,使生化处理成为可能,进生化池废水经稀释后,用活性污泥法处理９天后,ＣＯＤ从１．５万降至ＣＯＤ〈３００ｍｇ／Ｌ,达到治理要求。     

驯化活性污泥处理明胶有机废水的实验

利用驯化活性污泥对组分复杂的明胶有机废水进行有机物降解实验。结果表明,明胶废水的ＢＯＤ５／ＣＯＤｃｒ比值为０．４４－０．４６,ＣＯＤｃｒ进水浓度在１０００－１２００ｍｇ／Ｌ人,ＣＯＤｃｒ和ＢＯＤ５去除率分别达８１％－８３％和８６％－９１％。     

SBR法处理化学药物制剂废水

采用 ＳＨＲ法处理化学药物制剂废水． 调节 ｐＨ至７．５,进水 ＣＯＤｃｒ ２２４～１５３０ ｍｍ／Ｌ,曝气１０ ｈ, ＣＯＤｃｒ容积负荷达２．５８ｋｇ／ｍ~３·ｄ,ＣＯＤｃｒ的去除率高达９４．２％,处理后出水ＣＯＤｃｒ＜１００ｍｇ／Ｌ,达到综合排放标准（ＧＢ８９７－９６）一级标准。ＣＯＤｃｒ容积负荷至３．８４ ｋｇ／ｍ~３·ｄ, ＣＯＤｃｒ去除率仍＞８５．９％。     

水解酸化——好氧工艺处理混合化工废水

对某化工开发区混合化工废水进行预处理,物化出水采用厌氧水解－－好氧活性污泥法坦 步处理。研究了水力停留时间、有机负荷、容积负荷对处理效率的影响。结果表明,当上流工厌氧滤池进水ＣＯＤ浓度为７００－９００ｍｇ／Ｌ,经水解酸化－－好氧处理后出水ＣＯＤ去除率达６０％以上,色度、ＳＳ、ＢＯＤ去除率分别为８５％以上,５０￣６０％、９５％左右。经混凝沉淀、Ｆｅｎｔｏｎ试剂进一步处理,ＣＯＤ、色度可下降为１２４ｍ     

接触氧化——混凝沉淀法处理染色废水

进行了生物接触氧化法处理牛仔布染色废水的设计与工程试运转。结果表明，当废水ＣＯＤＣＲ平均浓度为５４６ｍｇ／Ｌ色度为４４８倍时，处理ＣＯＤＣＲ去除率为６８％，色度去除率８６％，出水基本能达到设计要求。     

Evaluation of trichloroethene recovery processes in heterogeneous aquifer cells flushed with biodegradable surfactants

The ability of two biodegradable surfactants, polyoxyethylene (20) sorbitan monooleate (Tween 80) and sodium dihexyl sulfosuccinate (Aerosol MA), to recover a representative dense non-aqueous-phase liquid (DNAPL), trichloroethene (TCE), from heterogeneous porous media was evaluated through a combination of batch and aquifer cell experiments. An aqueous solution containing 3.3% Aerosol MA, 8% 2-propanol and 6 g/l CaCl(2) yielded a weight solubilization ratio (WSR) of 1.21 g TCE/g surfactant, with a corresponding liquid-liquid interfacial tension (IFT) of 0.19 dyn/cm. Flushing of aquifer cells containing a TCE-DNAPL source zone with approximately two pore volumes of the AMA formulation resulted in substantial (>30%) mobilization of TCE-DNAPL. However, a TCE mass recovery of 81% was achieved when the aqueous-phase flow rate was sufficient to displace the mobile TCE-DNAPL toward the effluent well. Aqueous solutions of Tween 80 exhibited a greater capacity to solubilize TCE (WSR=1.74 g TCE/g surfactant) and exerted markedly less reduction in IFT (10.4 dyn/cm). These data contradict an accepted empirical correlation used to estimate IFT values from solubilization capacity, and indicate a unique capacity of T80 to form concentrated TCE emulsions. Flushing of aquifer cells with less than 2.5 pore volumes of a 4% T80 solution achieved TCE mass recoveries ranging from 66 to 85%, with only slight TCE-DNAPL mobilization (<5%) occurring when the total trapping number exceeded 2 x 10(-5). These findings demonstrate the ability of Tween 80 and Aerosol MA solutions to efficiently recover TCE from a heterogeneous DNAPL source zone, and the utility of the total trapping number as a design parameter for a priori prediction of DNAPL mobilization and bank angle formation when flushing with low-IFT solutions. Given their potential to stimulate microbial reductive dechlorination at low concentrations, these surfactants are well-suited for remedial action plans that couple aggressive mass removal followed by enhanced bioremediation to treat chlorinated solvent source zones.     

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.     

The variation of street air levels of PAH and other mutagenic PAC in relation to regulations of traffic emissions and the impact of atmospheric processes

The occurrence of particle associated PAH and other mutagenic PAC was determined in 1996 in the street air of Copenhagen. In addition, particle extracts were tested for mutagenicity. The measurements were compared with previous measurements in 1992/1993. The levels had decreased in this period. The decrease was caused by an implementation of light diesel fuels for buses and the exchange of older petrol-driven passenger cars with catalystequipped new ones. About 65% of the reduction was caused by the application of the light diesel fuels. Under special conditions, chemical processes in the atmosphere produced many more mutagens than the direct emissions. The concentrations of S-PAC and N-PAC were 10 times lower than those of PAH, while the levels of oxy-PAH were in the same order of magnitude as those of PAH. Benzanthrone, an oxy-PAH, is proposed to be formed in the atmosphere in addition to direct emissions. Benzo(a)pyrene, often applied as an air quality criteria indicator, was photochemically degraded in the atmosphere. A strong increase in the mutagenic activities was observed to coincide with a depletion of benzo(a)pyrene.     

Teratological effects of pesticides in vertebrates: a review

Abstract

In the last decades, the use and misuse of pesticides in the agriculture have increased, having a severe impact on ecosystems and their fauna. Although the various effects of pesticides on biodiversity have been already documented in several studies, to our knowledge no consistent overview of the impact of pesticides in vertebrates, both terrestrial and aquatic, is available. In this review, we try to present a concise compilation of the teratogenic effects of pesticides on the different classes of vertebrates – mammals, birds, reptiles, amphibians and fish.     

Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos national laboratory and the doses to humans from the consumption of muscle and bone

Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for ³H, ⁹⁰Sr, ¹³⁷Cs, ^totU, ²³⁸Pu, ^239,240Pu, and ²⁴¹Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of ⁹⁰Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g^‐1 [126E‐02 Bq kg^‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g^‐1 [518E‐02 Bq kg^‐1]). The differences in ⁹⁰Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y^‐1 (1.0 ± 1.0 μSv y^‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y^‐1 (1000 μSv y^‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.     

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.     

Patterns of volatile metabolites and nonvolatile trichothecenes produced by isolates of <Emphasis Type="Italic">Stachybotrys,Fusarium, Trichoderma,Trichothecium</Emphasis> and <Emphasis Type="Italic">Memnoniella</Emphasis>

We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.     

Observations on the influence of water and soil pH on the persistence of insecticides

Abstract

The pH‐disappearance rate profiles were determined at ca. 25°C for 24 insecticides at 4 or 5 pH values over the range 4.5 to 8.0 in sterile phosphate buffers prepared in water‐ethanol (99: 1 v/v). Half‐lives measured at pH 8 were generally smaller than at lower pH values. Changes in half lives between pH 8.0 and 4.5 were largest (>1000x) for the aryl carbamates, carbofuran and carbaryl, the oxime carbamate, oxamyl, and the organophosphorus insecticide, trichlorfon. In contrast, half lives of phorate, terbufos, heptachlor, fensulfothion and aldicarb were affected only slightly by pH changes. Under the experimental conditions described half lives at pH8 varied from 1–2 days for trichlorfon and oxamyl to >1 year for fensulfothion and cyper‐methrin. Insecticide persistence on alumina (acid, neutral and basic), mineral soils amended with aluminum sulfate or calcium hydroxide to different pH values and four natural soils of different pH was examined. No correlation was observed between the measured pH of these solids and the rate of disappearance of selected insecticides applied to them. These observations demonstrate the difficulty of extrapolating the pH dependent disappearance behaviour observed in homogeneous solution to partially solid heterogeneous systems such as soil.     

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.     

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.