含铬电镀废水中Cr(Ⅵ)的萃取分离研究

用体积分数为40％的磷酸三丁酯－煤油溶液为萃取剂,采用溶液萃取法处理含铬[Cr(Ⅵ）]电镀废水。预先调节废水中Cr(Ⅵ）的质量浓度约为100mg/L,溶液酸度为1．3－1．5mol/L,相比为1∶2,振荡时间为35min,于室温下进行二级萃取处理,Cr(Ⅵ）的萃取率可达到99％以上。萃余液中Cr(Ⅵ）的残余质量浓度降至0．5mg/L以下,达到国家排放标准。对负载有机相用质量分数为10％的Na2SO3溶液进行反萃,即可得到再生,循环使用。     

树脂吸附法去除水及空气中的CS2

采用XDA-1树脂吸附固定床工艺，对CS2饱和水溶液和含CS2的空气分别进行了动态吸附性能和影响因素的研究。在室温、CS2饱和水溶液流速为40BV／h（BV为树脂床体积）、中性或弱酸性的条件下，XDA—1树脂对水中饱和CS2的吸附效率达98．1％，对CS2的吸附量可达54．0g／L。在室温和气体流速为600BV／h的条件下，XDA-1树脂对空气中CS2的吸附效率为63．9％-90．0％，对CS2的吸附量可达28．0～36．8g／L。采用水蒸气解吸和冰水冷凝可以回收84．9％-90．0％的CS2。     

一种分离及回收污泥及土壤中重金属的新工艺

该发明公开了一种利用可生物降解的绿色高分子聚天冬氨酸作为萃取剂对城市污水厂污泥及土壤中的重金属实现有效分离，并实现重金属的回收和聚天冬氨酸的循环使用的新工艺，工艺步骤如下：首先制备污泥悬浮液；其次向悬浮液中添加聚天冬氨酸溶液，聚天冬氨酸与污泥中重金属总量的质量浓度比范围为0．1～10，再用酸碱溶液调节悬浮液后离心分离，根据试样中所含重金属离子种类及含量，用酸碱溶液调节离心分离得到的清液的pH及用不同类型的离子交换树脂分别对上述调节pH后的清液进行重金属的分离。     

树脂吸附法处理对氨基苯酚废水

采用自制的NDA-99特种复合功能树脂处理对氨基苯酚（PAP）生产废水,考察了各种因素对吸附和脱附效果的影响。小试实验结果得出的工艺条件为：吸附流量2．0BV／h,吸附温度15℃,单柱吸附量10BV;脱附剂为2BV盐酸（质量分数1．5％）＋2BV水。中试试验结果表明,在上述工艺条件下,NDA-99树脂处理PAP废水的吸附性能和脱附性能稳定,平均COD去除率约为93％,平均PAP脱附率达98％。     

树脂吸附法处理对硝基苯乙酮生产废水

采用AM-1吸附树脂和ND-900络合树脂对硝基苯乙酮生产废水进行吸附处理，试验结果表明，使用2种树脂串联的处理效果优于单独使用某一种树脂，而且ND-900络合树脂在前，AM-1吸附树脂在后串联处理的效果最好，废水体积为30BV时，COD去除率为92.8%；脱色率为100%，出水由原废水的橙红色变为无色，采用质量分数为8%的NaOH溶液作为脱附剂，脱附效果良好。     

树脂吸附法处理硝基苯和硝基氯苯生产废水的研究

研究了用ＣＨＡ－１１１树脂吸附处理硝基本和硝基氯苯生产废水的最佳工艺条件，当废水中硝基苯类化合物含量为６３９ｍｇ／Ｌ时，ＣＨＡ－１１１树脂的工作吸附容量为１２６ｍｇ／ｍＬ，处理水量为１９０ＢＶ，处理后硝苯类化合物的浓度〈５ｍｇ／Ｌ，去除率〉９９％；采用异丙醇作脱附剂；表明该树脂的吸附与脱附性能良好。     

一种含钒废水处理方法

该专利公开了一种含钒废水处理方法。该方法包括以下步骤：（1）将含铬和钒废水的pH调至小于7．0;（2）将（1）步骤的废水过离子交换树脂柱;（3）往（2）步骤的树脂中加入解吸剂得洗脱液;（4）将步骤（3）得到的洗脱液进行沉钒,过滤得滤液和滤饼;（5）将步骤（4）得到的含铬滤液进行处理制取铬产品;（6）将步骤（4）铁盐沉钒所得滤饼用碱溶液浸泡得钒溶液,再进行水解沉钒或铵盐沉钒。     

萃取法处理萤光废水

采用萃取法处理萤光废水，最佳萃取工艺条件如下：ｐＨ为１，废水：萃取剂：稀释剂为２０：２：５。在此工艺条件下，萤光废水ＣＯＤ去除率可达９１％－９８％，色度去除率达９９．８％。萃取剂可再生回用，在萃取相中按萃取剂（包括络合物）的量加入等体积的浓度为２０％的ＮａＯＨ溶液，在９５－１０５℃加热回流５－１０ｍｉｎ，即可使萃取剂得到再生。     

树脂吸附法处理磺胺中间体生产废水的研究

研究了树脂吸附法处理磺胺中间体生产废水的工艺过程，研究结果表明，NDA－900吸附树脂对该废水具有良好的吸附－脱附处理效果，在原废水中对氨基苯磺酸质量浓度为5000－6000mg/L，氨基值近5000mg/L,COD高达10000mg/L以上，经树脂吸附处理后（处理量为每批次12BV），对氨基苯磺酸的去除率大于96％，氨基值去除率大于65％，COD去除率大于55％，树脂脱附液经酸化结晶，过滤处理，可回收对氨基苯磺酸。     

离子交换树脂处理氨氮废水的试验研究

经过滤后的氨氮废水用离子交换树脂处理后,氨氮可达到排放标准。对废水的过滤特性、树脂筛选、吸附与洗脱等工艺条件进行了试验研究,确定采用732H 离子交换树脂吸附,以硫酸洗脱使树脂再生。硫酸铵洗脱液经浓缩后可作为副产物予以综合利用。     

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.     

Programs assessing implementation and effectiveness of state forest practice rules and BMPs in the West

The major forest nonpoint source control programs in the West are largely regulatory, either under forest practices acts (California, Idaho, New Mexico, Nevada, Oregon, and Washington) or a streamside management act (Montana). These programs and the specific rules they enforce continue to undergo intensive scrutiny. Still, the questions are the same for these regulatory programs as for states that base nonpoint source control on voluntary BMPs (Arizona, Colorado, Utah, Wyoming). Are the rules or BMPs being applied, and are they effective in reducing nonpoint source pollution to levels that protect beneficial uses of water? The level of debate about forestry in the West has resulted in detailed monitoring and research to answer these questions. In the past, state agencies have assumed levels of BMP compliance based on the percent of operations without enforcement actions. These estimates are being replaced by statistically valid and reproducible monitoring of forest practices rules and BMP compliance levels. BMP effectiveness is being assessed using both qualitative and quantitative methods. This can involve field assessments, process-based research, and control watershed studies. Some trend monitoring is also beginning. With the regional implementation rate for forestry BMPs at about 94% and rising, it is likely that effectiveness testing will continue to be a priority and consume the majority of assessment resources for this region.     

Hysteresis in Reversal of Central European Mountain Lakes from Atmospheric Acidification

Extremely high emissions of S and N compounds in Central Europe (both 280 mmol m^-2 yr^-1) declined by 70and 35%, respectively, during the last decade. Decreaseddeposition rates of SO₄ ^-2, NO₃ ^-, and NH₄ ⁺ in the region paralleled emission declines. The reduction in atmospheric inputs of S and N to mountain ecosystemshas resulted in a pronounced reversal of acidification in the Tatra Mountains and Bohemian Forest lakes. Between the 1987–1990and 1997–1999 periods, concentrations of SO₄ ^-2 and NO₃ ^- decreased (average ± standard deviation) by 22±7 and 12±7 mol L^-1, respectively, in theTatra Mountains, and by 19±7 and 15±10 mol L^-1, respectively, in the Bohemian Forest. Their decrease was compensated in part (1) by a decrease in Ca²⁺ + Mg²⁺ (17±7 mol L^-1) and H⁺ (4±6 mol L^-1), and an increase in HCO₃ ^-(10±10 mol L^-1) in the Tatra Mountains lakes, and (2) by a decrease in Al (7±4 mol L^-1), Ca²⁺ + Mg²⁺ (9±6 mol L^-1), and H⁺ (6±5 mol L^-1), in Bohemian Forest lakes. Despite the rapid decline in lake water concentrations of SO₄ ^-2 and NO₃ ^- in response to reduced S and N emissions, their present concentrations in some lakes are higher than predictionsbased on observed concentrations at comparable emission rates during development of acidification. This hysteresis in chemical reversal from acidification has delayed biological recovery of the lakes. The only unequivocal sign of biological recovery hasbeen observed in erné Lake (Bohemian Forest) where a cladoceran species Ceriodaphnia quadrangular has recentlyreached its pre-acidification abundance.     

Reconstruction of Long-Term Changes in Lake water Chemistry,Zooplankton and Benthos of a Small,Acidified High-Mountain Lake: Magic Modelling and Palaeolimnogical Analysis

Starolesnianske pleso is a small and shallow acid lake in the High Tatra Mountains, situated at 2000 m above sea level, on granitic bedrock, with sparse and thin soil cover. When detailed measurements began in the 1980s Starolesnianske pleso had pH below 5 and only one species of cladoceran zooplankton, the ubiquitous Chydorus sphaericusPalaeolimnological investigations show changes in cladoceran zooplankton and chironomid zoobenthic assemblages since about 1920 and a major change in 1970–1980. The dynamic acidification model MAGIC was used to reconstruct changes in water chemistry over the past 150 years. The results from MAGIC agree well with the sediment record; pH levels gradually decreased from 6.5 in the mid-1800s to about 5.6 in 1920 (first response in biota) to below 5.0 by 1970, and concentrations of inorganic aluminium rose dramatically beginning about 1960. In the 1990s the lake water chemistry showed clear signs of reversal in acidification brought about by a major decline in S deposition.     

Heavy Metals Removal by Biosorption and Flotation

The removal of a mixture of heavy (toxic) metal cations (copper, nickeland zinc) from liquid effluents was investigated in this study at pilotscale, using counter-current contact mode. The innovative processinvolved the abstraction of metal ions onto fungal biosorbents, followedby the application of flotation for the subsequent solid/liquid separationof biomass particles. The ability of microorganisms to remove metal ionsfrom aqueous solutions is a well-known phenomenon. Nevertheless,engineering considerations are very important in decisions, concerningthe commercial future of biosorption and practical solutions are neededfor certain problems, such as the efficient post-separation ofmetal-loaded biomass. The two processes (flotation and biosorption) caneffectively operate in combination, in what it was termed biosorptiveflotation process. The sorbents may be recycled, after appropriate elutionof metals, as well as the treated (clean) water.     

High Immobilization of NH4+ in Danish Heath Soil Related to Succession,Soil and Nutrients: Implications for Critical Loads of N

During recent decades heathlands havechanged into grasslands in regions with high atmosphericnitrogen deposition. In regions with intermediatedeposition level (e.g., Denmark) changes have been lesspronounced which may be due to delay or decrease inresponse of the ecosystem. The mor layer (O horizon) mayplay an important role for this delay due to high sinkstrength for N. In this study, the capacity for netNH₄ ⁺ immobilization and mineralization wasstudied during short- and long-term incubations (2–36 days)of mor samples from Danish dry inland heaths. High short-term capacity for net NH₄ ⁺ immobilization wasfound to be a general characteristic of Danish heath morlayers both under heather (Calluna vulgaris) andcrowberry (Empetrum nigrum ssp nigrum), the latterdominating late stages in heathland succession. The netNH₄ ⁺ immobilization was higher under youngcompared to old or dead vegetation, and higher on lessnutrient poor soils than on extremely nutrient poor soils.The addition of N, P and C stimulated CO₂ productionand net NH₄ ⁺ immobilization, but not net Nmineralization. The immobilization of ¹⁵NH₄ ⁺caused release of dissolved organic N, increased N anddecreased C/N ratio in the microbial biomass, and indicatedgrowth of microorganisms with other metabolic abilitiesthan the indigenous population. No evidence was obtained ofstabilization of immobilized ¹⁵NH₄ ⁺ intosoil organic matter during the experiment. On background ofthe results and current knowledge it was concluded that therecognition of the high capacity for net NH₄ ⁺immobilization in mor layers does not allow for a raiseof critical loads for N for northern dry inland heaths.     

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。     

Selection of Autochthonous Plant Species from SE Spain for Soil Lead Phytoremediation Purposes

Mining activity in SE of Spain, in the west Mediterranean coast, originated more than two millenniums ago. It has generated huge areas affected by heavy metals contamination, especially of lead, which is possibly one of the most important. Investigations related to the selection of autochthonous plant taxa from a typical Spanish Mediterranean area, useful for phytoextraction and phytostabilization purposes in these polluted areas are shown. Under these edaphoclimatic conditions 12 interesting species were considered, from them six taxa were chosen for further studies. Some plant species have been proposed either for phytoextraction or phytostabilization purposes. Recommendations for further research have been discussed.