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1.
刘涛  程迪  李鹏 《化工环保》2013,33(3):235-238
以磷酸三丁酯(TBP)为载体、煤油为膜溶剂、NaOH水溶液为内水相,采用乳状液膜法处理兰炭废水。实验结果表明:当TBP体积分数为4%、表面活性剂质量分数为4%、内水相NaOH质量分数为12%、油内比(乳状液的油相与内水相的体积比)为3∶2、乳水比为1∶5、萃取时间为15min时,废水中的酚类(以苯酚计)去除率达到85%以上,COD去除率达83%以上。  相似文献   

2.
以三辛胺为载体,煤油为膜溶剂,NaOH为反萃剂,采用大块液膜法处理模拟含Cr(Ⅵ)废水.考察了Cr(Ⅵ)迁移的影响因素,实验结果表明:在料液相进水Cr(Ⅵ)质量浓度为1043.6 mg/L、料液相进水pH为1.1、反萃相中NaOH质量分数为20%、液膜相体积为100 mL、液膜相中三辛胺体积分数为15%、反应时间为50 min的条件下,料液相出水Cr(Ⅵ)质量浓度为0.5 mg/L;萃取36批废水后Cr(Ⅵ)浓缩比可达94.2%.  相似文献   

3.
液膜法处理含硝基酚废水试验研究   总被引:3,自引:0,他引:3  
栾金义  李昕  王宜军 《化工环保》2003,23(4):195-199
采用液膜法对含硝基酚废水进行了处理试验研究。对低浓度废水选取了适宜的工艺条件:油相中表面活性剂的质量分数为2%;内水相中NaOH的质量分数为2%;乳液中油相与内水相的质量比为2:1;外水相:pH为2;乳液与外水相的体积比为1:3。在进水总酚质量浓度分别为1050、6700mg/L的条件下,出水总硝基酚的去除率均高达99.9%以上,同时废水中的硝基苯和COD也有较好的去除效果。  相似文献   

4.
混凝—催化氧化法处理丁苯橡胶生产废水   总被引:3,自引:0,他引:3  
郭青  赵旭涛  王维 《化工环保》2006,26(6):494-497
以聚合氯化铝(PAC)、阴离子聚丙烯酰胺(PAM)为混凝剂,以H2O2-O3为氧化剂,采用混凝-催化氧化法处理对丁苯橡胶生产废水。考察了混凝剂种类及其加入量、废水pH对混凝处理效果的影响,氧化剂及其加入量、反应时间和废水pH对COD去除率的影响。实验得出的最佳工艺条件:混凝实验,废水pH为7、PAC和PAM加入量为400mg/L和4mg/L;催化氧化实验,废水pH为7~8、H2O2加入量为200mg/L、H2O2与O3的质量比为0.5。处理后,废水COD从860mg/L降至145mg/L,COD去除率达83.1%,出水水质达到国家二级排放标准。  相似文献   

5.
改性粉煤灰吸附-高级氧化法处理奥里油废水   总被引:4,自引:1,他引:3  
将氯化铁改性粉煤灰(简称改性粉煤灰)吸附处理与高级氧化和生物处理等技术进行优化组合,以期得到简便而有效的处理奥里油废水(简称废水)的组合工艺。研究结果表明:在废水COD平均为4600mg/L、改性粉煤灰加入量为50g/L、废水pH为7~9、吸附时间为1h的条件下,COD去除率达30%。采用“改性粉煤灰一次吸附-湿式均相催化氧化-厌氧生物过程-改性粉煤灰二次吸附”组合工艺处理废水时,改性粉煤灰不但具有较好的预处理效果,且还有较好的后处理能力;湿式均相催化氧化的催化剂用量少(Cu(NO3)2为2.0g/L)、操作条件温和(2.5MPa,180℃,pH5—7,1h);厌氧生物过程中不需特殊筛选的菌种,易操作控制;经该组合工艺处理后,废水COD从4600mg/L降至55mg/L,COD去除率为98.4%,达到GB8978-1996《污水综合排放标准》的一级排放标准。  相似文献   

6.
采用酸化-萃取法处理齐鲁石化公司第二化肥厂的丁辛醇废水(简称废水),用硫酸调节废水的pH,以该厂产品异辛醇为萃取剂,考察了各种因素对萃取效率的影响,得出较佳工艺条件:废水的pH为2.5,废水与萃取剂的体积比为4,废水温度为10℃,废水与萃取剂混合时的振摇时间为60s,萃取相和萃余相的静置分离时间为10min。在该条件下对COD为42244mg/L的废水进行二级错流萃取,COD去除率为86.82%。该法可实现对废水进行处理和资源回收的双重目的。  相似文献   

7.
Fenton氧化-生物接触氧化工艺处理甲醛和乌洛托品废水   总被引:5,自引:3,他引:5  
采用Fenton氧化一生物接触氧化工艺处理含甲醛和乌洛托品的模拟废水(简称废水),在H2O2(体积分数30%)加入量2.5g/L、H2O2与Fe^2+质量浓度比3.75、反应时间3h、不调节废水初始pH的Fenton氧化预处理最佳操作条件下,废水COD从1000mg/L左右降至300mg/L,COD去除率达72%。原废水完全无法直接进行生化处理,经Fenton氧化预处理后其BOD,/COD约为0.5,易于生化处理。Fenton氧化一生物接触氧化工艺处理废水,生物接触氧化停留时间为12h时,废水COD去除率高达94%,处理后出水COD小于70mg/L,处理效果很好。  相似文献   

8.
自制电压为10kV的高压脉冲放电反应器,对质量浓度为200mg/L的模拟活性艳红K-2BP废水进行脱色和去除COD实验。实验结果表明:通氧气高压脉冲放电与高压脉冲放电相比,废水脱色率提高了1.3%,约为6%,COD去除率提高了3%,达14%;高压脉冲放电协同臭氧氧化与臭氧氧化相比,反应初期废水脱色率提高了约10%,反应30min后废水脱色率均达99%以上,COD去除率提高了15.2%,达80%。向废水中加入Na2CO3可使COD去除率明显下降;加入NaCl,在臭氧氧化条件下,COD去除率由66.86%降至58.86%;而加入Na2SO4后COD去除率升至81.70%。  相似文献   

9.
树脂吸附—Fenton氧化法处理精对苯二甲酸废水   总被引:4,自引:1,他引:4  
采用树脂吸附-Fenton加氧化法处理精对苯二甲酸(PTA)废水,考察了树脂吸附及Fenton氧化的最佳工艺条件。实验结果表明,采用NDA-88吸附树脂,在室温、吸附流速2BV/h条件下,每批次处理量为28BV,COD去除率为80%左右;采用Fenton试剂进一步氧化处理,在废水pH为3、质量分数30%的8202加入量为1.2%(体积分数)、H2O2与Fe^2+摩尔比为3:1、反应温度为40℃、反应时间为4h条件下,出水COD为72mg/L,COD去除率为87%,可达到国家一级排放标准。  相似文献   

10.
采用液膜萃取—酸析沉降—络合萃取组合工艺对有机磷阻燃剂生产废水进行预处理.最佳工艺条件为:液膜萃取时,液膜油相(表面活性剂与煤油的混合液)与内水相(H2SO4溶液)的体积比2∶1、乳化液膜与废水的体积比1∶8、废水pH 13.0,硫酸体积分数10%、煤油中表面活性剂质量浓度30 g/L、液膜萃取时间 15 min;酸析沉降时,废水pH l.0,酸析沉降时间30 min;络合萃取时,络合萃取剂(烷基叔胺N235与煤油的混合液)中烷基叔胺N235体积分数30%,络合萃取剂与废水的体积比1∶4,废水pH l.0,络合萃取时间30 min.在此最佳处理条件下,废水COD总去除率可达93%,吡啶去除率达99.9%以上,总磷去除率可达97%,BOD5/COD提高至0.32,有利于后续生化处理.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
Stuchlík  E.  Appleby  P.  Bitušík  P.  Curtis  C.  Fott  J.  Kopáček  J.  Pražáková  M.  Rose  N.  Strunecký  O.  Wright  R. F. 《Water, Air, & Soil Pollution: Focus》2002,2(2):127-138
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
Concentrations and Pools of Heavy Metals in Urban Soils in Stockholm,Sweden   总被引:8,自引:0,他引:8  
The concentrations of heavy metals (Cd, Cr, Cu, Hg, Ni, Pb andZn) and arsenic (As) were surveyed and the metal pools estimatedin soils in Stockholm Municipality. The sampling sites were distributed all over the entire municipality with a higher sampling density in the city centre. Soils were sampled to a maximum depth of 25 to 60 cm. Soil texture, total-C content, electrical conductivity and pH were analysed. Heavy metal concentrations were determined after wet digestion with boiling7 M HNO3.The results showed a wide range in heavy metal concentrations, as well as in other soil properties. The city centre soils constituted a rather homogeneous group whereas outside this areano geographical zones could be distinguished. These soils were grouped based on present land use, i.e. undisturbed soils, public parks, wasteland (mainly former industrial areas), and roadside soils. The city centre and wasteland soils generally hadenhanced heavy metal concentrations to at least 30 cm depth compared to park soils outside the city centre and rural (arable)soils in the region, which were used to estimate background levels. For example, the mean Hg concentration was 0.9 (max 3.3)mg kg-1 soil at 0–5 cm and 1.0 (max 2.9) at 30 cm depth in the city centre soils, while the background level was 0,04 mg kg-1. Corresponding values for Pb were 104 (max 444) and135 (max 339) mg kg-1, at 0–5 and 30 cm, respectively, while the background level was 17 mg kg-1.The average soil pools (0–30 cm depth) of Cu, Pb and Zn were 21,38 and 58 g m-2 respectively, which for Pb was 3–4 timeshigher and for Cu and Zn 1.5–2 times higher than the backgroundlevel. The total amount of accumulated metals (down to 30 cm)in the city centre soils (4.5*10 6 m2 public gardens and green areas) was estimated at 80, 1.1, 120 and 40 t for Cu, Hg, Pb and Zn, respectively. The study showed (1) thatfrom a metal contamination point of view, more homogeneous soilgroups were obtained based on present land use than on geographicdistance to the city centre, (2) the importance of establishing a background level in order to quantify the degree of contamination, and (3) soil samples has to be taken below the surface layer (and deeper than 30 cm) in order to quantify theaccumulated metal pools in urban soils.  相似文献   

17.
针对近年我国频繁出台的电子废物回收处理产业政策,系统论述了其发展脉络,并从循环经济角度出发,分析了我国电子废物产业发展的主体思路,同时还对我国电子废物回收处理产业发展机遇与存在的问题进行剖析,对如何稳定企业的电子废物来源、提升产业技术水平及降低企业运营成本进行建议性分析。  相似文献   

18.
Nitrous oxide emission from some English and Welsh rivers and estuaries   总被引:4,自引:0,他引:4  
Nutrient and N2O concentrations in the water columns were measured seasonally over a full salinity range in the nutrified rivers Colne, Stour, Orwell, Deben, Trent, Ouse and Humber and their estuaries on the east coast of England between August 2001 and May 2002, and in the oligotrophic rivers Conwy, Dovey and Mawddach in North and West Wales between August 2002 and May 2003. Nutrient and N2O concentrations in the nutrified English rivers and estuaries were much higher than those in the Welsh rivers. N2O concentrations and % saturation in the estuaries were significantly correlated with nitrate, nitrite and ammonium concentrations in the water. The strongest correlation was with nitrite (r2 = 0.56, p < 0.01), suggesting that nitrite was the most significant factor among the different nutrients in regulating N2O concentration in the estuaries. N2O concentrations in the English rivers and estuaries were supersaturated throughout the year with annual averages from 186.9 to 992.9%, indicating that these rivers and estuaries were sources of atmospheric N2O, whereas in the Welsh rivers N2O concentrations were much lower with annual averages from 113.6 to 137.4% saturation. Although the estuarine area in the Colne was almost the same as that in the Conwy, the annual N2O emission from the Colne was much higher (937498 mol N yr–1) than in the Conwy (23020 mol N yr–1). On the east coast, riverine emissions of N2O were only 0.5–12.5% of the total emission from rivers and estuaries. Thus rivers were negligible, but estuaries were significant contributors to the UK N2O inventory.  相似文献   

19.
Long-term (i.e. >10 years) whole community fish dataincluding catch-per-unit-effort, abundance, biomass, andproduction from three lakes were used: 1) to examine variabilityin fish population and community measures among years using wholelake assessments of fish populations derived from mark recaptureexperiments, 2) to assess implications arising from monitoringindividual species vs. the whole fish community, and 3) toascertain whether, in fisheries assessments (science) a commonlyused surrogate measure, [catch-per-unit-effort (CPUE)] reflectedannual changes in the fish assemblage, and thus may be a goodestimator of abundance. High, long-term variability was evident in the abundance andbiomass of a fish species in our lakes, yet the communityremained relatively stable in terms of its biomass andproduction. Changes in total fish community biomass appear drivenby large species, which, relative to small fish species, remainstable among years. Among years, species richness remainedstable; however, fish species changed in the community. AnnualCPUE was found to be a suitable surrogate for abundance (N) ofsmall fishes; CPUE x mean weight of the catch (bCPUE) was asuitable surrogate for biomass (B) of large fishes. Prior toconcluding that a change in a fish population has occurred as aresult of a stressor, care must be taken to critically examinethe level of population assessment in order to avoid acceptingpotentially invalid conclusions.  相似文献   

20.
The abundance and photosynthetic activity ofpicocyanobacteria in the oligotrophic alpine lake Traunseewere measured at a station located close to the outlet ofindustrial soda waste and at a mid-lake reference stationduring spring, 1999 through to autumn, 2000.Picocyanobacterial numbers measured by flow cytometry inTraunsee (0.7–13.2 × 104 ml-1) were comparable tothose of other oligotrophic lakes, and there was nosignificant difference between the contaminated and thereference sampling location. Picoplankton (<2 m)photosynthetic rates measured in vitro by the 14C-technique were significantly reduced at the contaminated siterelative to the reference station at low photosyntheticallyavailable radiation (10 E m-2 s-1), while nodifference between these two stations was found at moderatelyhigh light intensity (100 E m-2 s-1). Theinvestigation was complemented by laboratory experiments withcultured picocyanobacteria. Three Synechococcus spp.strains were exposed to water taken from either of the twoTraunsee stations and from a control station located inneighbouring Attersee. Cell-specific photosynthetic activitymeasured by 4-h in vitro incubations revealed no significantdifference among the three stations investigated. Growthrates of the same three Synechococcus spp. strains weremeasured by flow cytometry over several days in thelaboratory. One strain, in particular, was sensitive to watertaken from the contaminated site; growth rate of this strainwas significantly reduced, relative to when exposed to watertaken from the reference station. Taken together, our resultsdemonstrate that picocyanobacteria are highly sensitivebioindicators of contaminant stress. The overall impact ofthe emissions from the industrial outlet on thepicocyanobacteria was, however, relatively minor.  相似文献   

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