生物接触氧化法处理腈纶废水中硫氰酸钠

以硫氰酸钠作溶剂制造腈纶纤维和生产硫氰酸钠的废水中均含有一定量的硫氰酸钠。上海石化总厂腈纶厂采用生物塔式滤池处理,对硫氰酸钠不起降解作用。为了完善睛纶废水处理,消除污染,保护环境及进一步达到废水回用之目的。我们采用经硫氰酸钠驯化过的活性污泥,用生物接触氧化法对腈纶废水中硫氰酸钠进行处理,效果非常明显,出水CODC_(cr)在100毫克/升以下,BOD-5平均小于20毫克/升,硫氰酸钠一般小于2毫克/升。     

对苯二甲酸降解菌固定化生物流化床处理精对苯二甲酸废水

采用微生物筛选、纯化技术,获得了降解对苯二甲酸（TA）的YPC—TA1,YPC—TA2,YPC-TA3,YPC—TA44株菌株。将筛选出的TA降解菌固定化,处理初始TA质量浓度为2650mg／L的模拟废水,降解36h后TA去除率达100％。用TA降解芮在生物流化床反应器中处理PTA废水,最佳容积负荷为6.7kg／（m^3·d）。生物流化床反应器可在容积负荷为6．0～6．5kg／（m^3·d）的较佳条件下长周期稳定运行,COD去除率保持在91％左右,TA去除率保持在94％左右。低pH废水冲击和高容积负荷废水冲击时COD,TA去除率均明显下降,恢复正常讲水后3～4d,COD,TA去除率均恢复正常。     

声化学氧化－间歇式活性污泥法处理染料废水的研究

介绍了声化学氧化反应机理。采用声化学氧化法作预处理，可使生物难降解的靛兰染料废水的ＢＯＤ＿５／ＣＯＤ由０．２１—０．２３提高到０．４４—０．５１，再经间歇式活性污泥法处理后，各项水质指标均符合ＧＢ８９７８—８８《污水综合排放标准》。     

液蜡氧化制仲醇废水的生物处理

液蜡氧化制仲醇生产过程排出的高浓度有机废水,采用厌气-好气两段生物处理流程优于生物接触氧化法一段处理流程。进水 COD 为10000毫克/升,厌气滤池负荷为5.2公斤 COD/米~3·天,COD 去除率达84%,两段处理 COD 总去除率为97%。     

麦迪霉素废水的两级好氧处理

采用三相生物流化床－生物接触固定床两级串联好氧生物处理流程，可处理ＣＯＤ高达２００００ｍｇ／Ｌ的麦迪霉素高浓度有机废水，两床的容积负荷分别为４．４４和０．８９ｋｇＣＯＤ／ｄ·ｍ＾３以下时，其ＣＯＤ和ＢＯＤ的去除率均在９０％以上，出水水质较好。本流程能够承受高浓度有机物的冲击负荷，对进水中的麦迪霉素和酚类物质有较强的适应能力，可保持稳定运行。     

臭氧氧化法处理染料中间体1—氨基蒽醌和DSD酸生产废水

采用臭氧氧化法处理染料中间体１－氨基蒽醌和ＤＳＤ酸生产废水，能改善废水的可生化性，降低废水中有机物的水溶性，提高混凝处理的效率。研究结果表明，在原水ＰＨ条件下，当臭氧投加量为７．５ｇ／Ｌ时，ＤＳＤ酸氧化母液脱色率大于９０％，ＢＯＤ５／ＣＯＤ达到０．３。当臭氧投加量为６ｇ／Ｌ时，１－氨基蒽醌废水的ＢＯＤ５／ＣＯＤ达到０．３。１－氨基蒽醌废水经投加量为２．５ｇ／Ｌ的臭氧处理后，再进行两级混凝处理，ＣＯ     

高级氧化—生化组合工艺处理难降解有机废水的研究进展

综述了近五年来(2004～2008年)高级氧化与生化组合工艺处理难降解有机废水的研究进展,提出了根据废水水质对高级氧化与生物处理技术进行合理组合的原则,同时还介绍了用高级氧化-生化组合工艺处理难降解有机废水的工程实例。     

两段生物接触氧化法处理甲胺磷生产废水

介绍了两段生物接触氧化法处理甲胺磷生产废水的试验情况。胺化废水脱氨后与甲基氯化物废话水按比例混合并稀释后，进行两段生物接触氧化处理，当进水ＣＯＤ３００ｍｇ／Ｌ、有机磷８００ｍｇ／Ｌ左右时，出水ＣＯＤ＜２００ｍｇ／Ｌ，有机磷＜２５ｍｇ／Ｌ。     

抗蚜威农药废水处理

在抗蚜威农药的生产过程中，排出α－甲基乙酰乙酸乙酯合成废水和抗蚜威合成废水。前者采用萃取法回收α－甲基乙酰乙酸乙酯和乙酰乙酸乙酯，简单蒸馏－精馏法回收甲醇；后者采用萃取法回收甲基嘧啶醇中间体。两股废水经预处理后，ＣＯＤ去除率分别达到９７％和７５％，ＢＯＤ５／ＣＯＤ从０．１－０．２提高到０．４，预处理后的废水混合后进行生物接触氧化处理，ＣＯＤ和ＢＯＤ５去除率分别达到８５％和９８％。     

声化学氧化—间歇式活性污泥法处理染料废水的研究

介绍了声化学氧化反应机理。采用声化学氧化法作预处理，可使生物难降解的靛兰染料废水的ＢＯＤ５／ＣＯＤ由０．２１－０．２３提高到０．４１－０．５１，再经间歇式活性污泥法处理后，各项水质指标均符合ＧＢ８９７８－８８《污水综合排放标准》。     

Distribution of Cd,Ck, Pb and Zn in Soil and Vegetation Compartments in Stands of Five Boreal Tree Species in N.E. Sweden

Concentrations and total quantity of cadmium (Cd), cupper (Cu),lead (Pb) and zink (Zn) were determined in biomass and soil compartments in a replicated tree species experiment with 27-yr-old stands growing on former farmland in N.E. Sweden. Sequentialextractions of soil samples were performed in order to estimate the exchangeable and an organically bound fraction of each element. The tree species included were Picea abies (L.)H. Karst., Pinus sylvestris L., Pinus contorta Dougl., Larix sibirica Ledeb., and Betula pendula Roth.Tree species influenced the rate of removal of Cu, Pb and Zn incase of stemwood harvesting, and of Cd, Cu and Zn in the case ofwhole-tree harvesting. B. pendula and P. abies had higher quantities and average concentrations of Zn in the biomass. For all species, >50% of the Zn in the stems was found in the bark. P. abies and L. sibirica had higher quantities of Cu in the biomass than the other species.P. abies and P. contorta had high quantities of Cd inthe biomass in relation to the other species. Branches and stembark contained high concentrations of Cd and Pb in relation to foliage and stemwood. Dead branches had especially high concentrations of Pb. The high accumulation rate of Zn in thebiomass of B. pendula was related to a low exchangeable amount of Zn in the A horizon. In the superficial centimeters ofthe A horizon, a depletion similar to that found for Zn was detected for Cu, whereas for Cd and Pb, no correlations were found between quantities of elements in the trees and element pools in the soil.     

Starch-plastic materials—Preparation,physical properties,and biodegradability (a review of recent USDA research)

Recent starch-plastic research at the National Center for Agricultural Utilization Research is reviewed and related worldwide efforts are noted. Properties of starch that influence its formulation and performance in plastics are discussed. Methods are given for preparation of starch-poly(methyl acrylate) graft copolymer, starch-poly(ethylene-co-acrylic acid), and starch-poly(ethylene-co-acrylic acid)-polyethylene plastics. Their physical properties are discussed, as is degradability by enzymes or amylolytic organisms from soil, ponds, and streams.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.     

Application of Cellulose Microfibrils in Polymer Nanocomposites

Cellulose microfibrils obtained by the acid hydrolysis of cellulose fibers were added at low concentrations (2–10% w/w) to polymer gels and films as reinforcing agents. Significant changes in mechanical properties, especially maximum load and tensile strength, were obtained for fibrils derived from several cellulosic sources, including cotton, softwood, and bacterial cellulose. For extruded starch plastics, the addition of cotton-derived microfibrils at 10.3% (w/w) concentration increased Young’s modulus by 5-fold relative to a control sample with no cellulose reinforcement. Preliminary data suggests that shear alignment significantly improves tensile strength. Addition of microfibrils does not always change mechanical properties in a predictable direction. Whereas tensile strength and modulus were shown to increase during addition of microfibrils to an extruded starch thermoplastic and a cast latex film, these parameters decreased when microfibrils were added to a starch–pectin blend, implying that complex interactions are involved in the application of these reinforcing agents.     

四氮唑废水处理工艺设计

高浓度、高盐分的四氮唑生产废水通过三效蒸发浓缩,馏出液经铁炭氧微电解和混凝预处理,再采用水解酸化一接触氧化一反应二沉主体组合工艺进行处理。研究了该工艺所需构筑物和设备的设计与选型。该工艺在正常运行条件下,处理后出水pH6～9,COD 302mg／L,BOD5 108mg／L,SS30mg／L,色度36倍,水质达到GB8978--1996（污水综合排放标准》三级标准。     

Bioassessment of silvicultural impacts in streams and wetlands of the Eastern United States

Bioassessment is a useful tool to determine the impact of logging practices on the biological integrity of streams and wetlands. Measuring biota directly has an intuitive appeal for impact assessment, and biota can be superior indicators to physical or chemical characteristics because they can reflect cumulative impacts over time. Logging can affect stream and wetland biota by increasing sedimentation rates, altering hydrologic, thermal, and chemical regimes, and changing the base of food webs. Biotic impacts of logging on streams compared to wetlands probably differ, and in this paper we review some of those differences. In streams, invertebrates, fishes, amphibians, algae, and macrophytes have been used as indicators of logging impacts. In wetlands, bioassessment is just beginning to be used, and plants and birds are the most promising indicator taxa. Various best management practices (BMPs) have been developed to reduce the impacts of logging on stream and wetland biota, and we review quantitative studies that have evaluated the efficacy of some of these techniques in streams and wetlands in the eastern United States. Remarkably few studies that address the overall efficacy of BMPs in limiting biotic changes in streams and wetlands after BMP implementation have been published in scientific journals, although some work exists in reports or is unpublished. We review these works, and compile conclusions about BMP efficacy for biota from this body of research.     

Characterization of air emissions and residual ash from open burning of electronic wastes during simulated rudimentary recycling operations

Air emissions and residual ash samples were collected and analyzed during experiments of open, uncontrolled combustion of electronic waste (e-waste), simulating practices associated with rudimentary e-waste recycling operations. Circuit boards and insulated wires were handled separately to simulate processes associated with metal recovery. The average emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDD/PCDFs) were 92 ng toxic equivalency (TEQ)/kg [n = 2, relative standard deviation (RSD) = 98%] and 11 900 ng TEQ/kg (n = 3, RSD = 50%) of the initial mass of the circuit boards and insulated wire, respectively. The value for the insulated wire is about 100 times higher than that for backyard barrel burning of domestic waste. The emission concentrations of polybrominated dibenzodioxins and dibenzofurans (PBDD/PBDFs) from the combustion of circuit boards were 100 times higher than for their polychlorinated counterparts. Particulate matter (PM) sampling of the fly ash emissions indicated PM emission factors of approximately 15 and 17 g/kg of the initial mass for the circuit boards and insulated wire, respectively. Fly ash samples from both types of e-waste contained considerable amounts of several metallic elements and halogens; lead concentrations were more than 200 times the United States regulatory limits for municipal waste combustors and 20 times those for secondary lead smelters. Leaching tests of the residual bottom ash showed that lead concentrations exceeded U.S. Environmental Protection Agency landfill limits, designating this ash as a hazardous waste.     

Does Soil Acidification Affect Spruce Needle Chemical Composition and Tree Growth?

In 1994, a large survey of soil chemistry was undertaken in thecounty of Värmland in central Sweden (Lundström et al., 1998).The southern part of the county was affected by soilacidification whereas there were no such indications in thenorthern part. To investigate the influence of soil chemistryon the trees at the specific sites, the survey was continued byan analysis of needle chemistry (Norway spruce) which wasundertaken at 150 of the 180 sites, and of tree growth at 65 ofthe 180 sites. Growth was expressed as a ratio between expectedgrowth, estimated with a national, empirical growth model, andthe growth observed in the field. In statistical analyses,using rank correlation, PCA and PLS, there were only weakindications of an influence of soil chemistry on needlechemistry and on tree growth. A moderate correlation betweennitrogen and sulphur in needles was found, which wasinterpreted as an effect of deposition and of processes in thetree canopy. No obvious regional pattern of the growth ratiowas found, in contrast to the clear pattern of soilacidification. The statistical analysis could not with anycertainty point out any of the soil chemistry variables asespecially important for the tree growth ratio.     

Solubility and Potential Mobility of Heavy Metals in Two Contaminated Urban Soils from Stockholm,Sweden

The solubility and potential mobility of heavy metals (Cd, Cu,Hg, Pb and Zn) in two urban soils were studied by sequential andleaching extractions (rainwater). Compared to rural (arable) soils on similar parent material, the urban soils were highlycontaminated with Hg and Pb and to a lesser extent also with Cd,Cu and Zn. Metal concentrations in rainwater leachates were related to sequential extractions and metal levels reported fromStockholm groundwater. Cadmium and Zn in the soils were mainly recovered in easily extractable fractions, whereas Cu and Pb were complex bound. Concentrations of Pb in the residual fractionwere between two- and eightfold those in arable soils, indicatingthat the sequential extraction scheme did not reflect the solidphases affected by anthropogenic inputs. Cadmium and Zn conc. inthe rainwater leachates were within the range detected in Stockholm groundwater, while Cu and Pb conc. were higher, whichsuggests that Cu and Pb released from the surface soil were immobilised in deeper soil layers. In a soil highly contaminatedwith Hg, the Hg conc. in the leachate was above the median concentration, but still 50 times lower than the max concentration found in groundwater, indicating the possibilityof other sources. In conclusion, it proved difficult to quantitatively predict the mobility of metals in soils by sequential extractions.     

Biodegradation of Injection Molded Starch-Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) Blends in a Natural Compost Environment

Injection molded specimens were prepared by blending poly (hydroxybutyrate-co-valerate) (PHBV) with cornstarch. Blended formulations incorporated 30% or 50% starch in the presence or absence of poly-(ethylene oxide) (PEO), which enhances the adherence of starch granules to PHBV. These formulations were evaluated for their biodegradability in natural compost by measuring changes in physical and chemical properties over a period of 125 days. The degradation of plastic material, as evidenced by weight loss and deterioration in tensile properties, correlated with the amount of starch present in the blends (neat PHBV < 30% starch < 50% starch). Incorporation of PEO into starch-PHBV blends had little or no effect on the rate of weight loss. Starch in blends degraded faster than PHBV and it accelerated PHBV degradation. Also, PHBV did not retard starch degradation. After 125 days of exposure to compost, neat PHBV lost 7% of its weight (0.056% weight loss/day), while the PHBV component of a 50% starch blend lost 41% of its weight (0.328% weight loss/day). PHB and PHV moieties within the copolymer degraded at similar rates, regardless of the presence of starch, as determined by ¹H-NMR spectroscopy. GPC analyses revealed that, while the number average molecular weight (Mn) of PHBV in all exposed samples decreased, there was no significant difference in this decrease between neat PHBV as opposed to PHBV blended with starch. SEM showed homogeneously distributed starch granules embedded in a PHBV matrix, typical of a filler material. Starch granules were rapidly depleted during exposure to compost, increasing the surface area of the PHBV matrix.     

Historical Weathering Based on Chemical Analyses of Two Spodosols in Southern Sweden

Chemical weathering losses were calculated for two conifer stands in relation to ongoing studies on liming effects and ash amendments on chemical status, soil solution chemistry and soil genesis. Weathering losses were based on elemental depletion trends in soil profiles since deglaciation and exposure to the weathering environment. Gradients in total geochemical composition were assumed to reflect alteration over time. Study sites were Horröd and Hasslöv in southern Sweden. Both Horröd and Hasslöv sites are located on sandy loamy Weichselian till at an altitude of 85 and 190 m a.s.l., respectively. Aliquots from volume determined samples from a number of soil levels were fused with lithium metaborate, dissolved in HNO₃, and analysed by ICP – AES. Results indicated highest cumulative weathering losses at Hasslöv. The weathering losses for the elements are in the following order:Si > Al > K > Na > Ca > MgTotal annual losses for Ca+Mg+K+Na, expressed in mmol_c m^-2 yr^-1, amounted to c. 28 and 58 at Horröd and Hasslöv, respectively. Variations between study sites could not be explained by differences in bulk density, geochemistry or mineralogy. The accumulated weathering losses since deglaciation were larger in the uppermost 15 cm than in deeper B horizons for most elements studied.