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1.
实验研究了不同pH、温度:Mg2+投量和沉降时间下,镁盐、炉渣、镁盐+炉渣3种处理对模拟和实际印染废水的脱色效果。结果表明,在pH为11~11.5、沉降30rain、30℃及Mg2+投加量为500~600mg/L的最优脱色条件下,3种处理对艳红FXC模拟废水的最大脱色率分别为98.41%、98.43%和99.37%,对实际印染废水的最大脱色率分别为90.18%、89.63%和93.33%,其中,镁盐+炉渣脱色效果最好,这可能与炉渣吸附和起到协同增强Mg(OH)2沉淀效果的作用有关。对水样的液相色谱初步检测分析表明,实际废水脱色处理前后染色基团峰高和种类发生了变化。该研究对盐田富镁卤水和炉渣等废物的资源化开发有重要参考价值。  相似文献   

2.
实验研究了不同pH、温度、Mg2+投量和沉降时间下,镁盐、炉渣、镁盐+炉渣3种处理对模拟和实际印染废水的脱色效果。结果表明,在pH为11~11.5、沉降30 min、30℃及Mg2+投加量为500~600 mg/L的最优脱色条件下,3种处理对艳红FXC模拟废水的最大脱色率分别为98.41%、98.43%和99.37%,对实际印染废水的最大脱色率分别为90.18%、89.63%和93.33%,其中,镁盐+炉渣脱色效果最好,这可能与炉渣吸附和起到协同增强Mg(OH)2沉淀效果的作用有关。对水样的液相色谱初步检测分析表明,实际废水脱色处理前后染色基团峰高和种类发生了变化。该研究对盐田富镁卤水和炉渣等废物的资源化开发有重要参考价值。  相似文献   

3.
絮凝-Fenton试剂氧化处理印染废水   总被引:1,自引:0,他引:1  
采用Fenton试剂对某染袜厂2种印染废水(印染红和印染蓝)进行处理。考察了硫酸亚铁投加量、双氧水投加量、反应时间及pH值对印染废水的色度及COD去除率的影响,通过正交实验确定了Fenton试剂处理该废水的最佳操作条件为:反应时间30 min、双氧水(30%)投加量4 mL/L、硫酸亚铁投加量300 mg/L、pH值为4左右。在最佳条件下,印染蓝废水经氧化处理后COD去除率大于80%,色度去除率95%以上;印染红废水需经絮凝预处理后再用Fenton试剂氧化处理,其脱色率达到了99.6%,COD去除率为91.2%,出水COD浓度为96 mg/L,可达标排放。  相似文献   

4.
Fe0-厌氧微生物体系处理活性艳红X-3B的试验研究   总被引:1,自引:0,他引:1  
采用间歇式摇床试验,研究了葡萄糖共基质条件下Fe0-厌氧微生物体系中Fe0投加量、pH值、染料初始浓度对活性艳红X-3B模拟废水脱色率的影响,比较了Fe0-厌氧微生物、纯厌氧微生物及纯Fe03种体系中废水的脱色效果.结果表明:Fe0-厌氧微生物体系中初始浓度(50~500 mg/L)对活性艳红X-3B的脱色率影响不大;而Fe0投加量、pH值存在一个最佳范围;当Fe0投加量为260 mg/L,pH值为6.0,污泥浓度为0.35 g VSS/L,停留时间约为30 h时,体系中活性艳红X-3B的脱色率可达90%左右,比相同试验条件下纯Fe0、纯厌氧微生物体系达到此脱色率所需时间分别缩短了约1/2、7/10.在Fe0-厌氧微生物体系中,由紫外可见分光光度分析可推测活性艳红X-3B的脱色机理主要是其偶氮键发生断裂,生成苯胺和萘类物质,而且苯胺和萘类物质能得到进一步降解.  相似文献   

5.
改性硅藻土复合混凝剂处理深度采油废水   总被引:1,自引:0,他引:1  
某油田深度采油废水中含有大量残油,粘度大、乳化程度高、油水分离困难,本实验采用改性硅藻土吸附和无机混凝剂混凝相结合以处理深度采油废水.结果表明,对于含油浓度为250~ 350 mg/L的石油废水,用强化吸附方法,吸附剂投加量为1.5 g/L,优化实验条件下除油率可达到75%;采用强化混凝的方法,PAC在投药量为200 mg/L的情况下除油率可达到87%;采用强化吸附-混凝联合处理的优化方法,投加0.7 g/L吸附剂+PAC 200 mg/L,除油率>95%,明显高于吸附和混凝单独处理效果,大大改善了出水水质.  相似文献   

6.
采用共沉淀法合成出一系列镁铝摩尔比不同的碳酸根型水滑石(LDHs),经500℃高温煅烧制备出镁铝复合氧化物CLDH,并用X-射线、红外光谱对它们进行表征。考查了吸附剂投加量、反应时间、初始pH值等因素对LDHs和CLDH处理阴离子染料活性艳红X-3B模拟废水效果的影响,并对吸附机理进行探讨。实验结果表明:以镁铝摩尔比为3∶1时制得的水滑石对活性艳红X-3B溶液的脱色效果最好。水滑石LDHs及其焙烧产物CLDH对活性艳红X-3B染料均具有较好的吸附性能,最佳反应时间分别为60 min和30 min;在较宽的pH范围内二者的脱色性能稳定,且CLDH对该染料的吸附效果要优于LDHs。LDHs及CLDH对活性艳红X-3B的吸附结果符合Langmuir吸附等温式,25℃下饱和吸附量分别为263.77 mg/g和875.23 mg/g。LDHs及CLDH的吸附机理分别为离子交换和层状结构重建。饱和吸附后的CLDH用高温热解法再生,吸附性能良好,随再生次数增多,脱色率下降。  相似文献   

7.
混凝法深度处理废纸造纸废水实验研究   总被引:4,自引:2,他引:2  
按照烧杯实验方法,重点考察了pH值、混凝剂种类和投加量等因素对生化处理后废纸造纸废水混凝处理效果的影响。实验结果表明:PAC作为混凝剂,PAM作为助凝剂联合处理该废水时,能够取得较好的去浊率、SS、色度和COD去除率。混凝沉淀最佳运行条件为:废水pH为6.5,含铝量10%的PAC和2 g/L的PAM投加量分别为1 mL/L、0.5 mL/L,浊度从35 NTU降低到1 NTU,去除率达97.1%,SS从30 mg/L降低到7 mg/L,去除率达76.7%,色度从64倍降低到18倍,去除率达71.9%,COD从95 mg/L降低到44.8 mg/L,去除率可达52.8%,取得了较好的去除效果,达到国家造纸废水新排放标准限值。  相似文献   

8.
以Fe3O4/TiO2作为磁性光催化剂,采用光磁耦合技术处理模拟印染废水。利用统计学方法对光磁耦合废水处理的影响因素进行了探讨和分析,考察了磁场强度、磁性光催化剂投加量、pH值和光照时间对光磁耦合废水处理的影响。通过Design-Expert 7.0.0软件分析得到最佳工艺条件:磁场强度73.95 mT,磁性光催化剂投加量1.13 g/L,模拟废水pH值13,光照时间120 min。在最佳工艺条件下进行实验,脱色率为88.60%。  相似文献   

9.
以粉煤灰为载体,制备铁/粉煤灰负载型催化剂,并利用该催化剂催化H2O2氧化降解活性黄染料废水,探讨了H2O2投加量、催化剂投加量、染料初始浓度和初始pH值等因素对染料废水COD去除率和脱色率的影响。结果表明,当染料废水COD初始浓度为200 mg/L,初始pH值为1.7,投加0.5 g/100 mL催化剂及加入1.0 mL浓度为1.13 mol/L的H2O2溶液时,处理效果最好,此时染料废水的COD去除率和脱色率分别达到63%和99%,并且废水的可生化性得到很大的提高。利用该负载催化剂能够有效地减少活性黄染料废水中Fe3+的残留量。  相似文献   

10.
分别用层状氢氧化镁铝(LDH)和焙烧层状氢氧化镁铝(CLDH)作为吸附剂吸附脱除水溶液中偶氮染料酸性黑10B.考察了脱色时间、pH值、吸附剂的投加量、温度、染料初始浓度和焙烧温度等因素对脱色率的影响.结果表明,LDH及CLDH对酸性黑10B染料具有良好的脱除效果,室温下,10g/L LDH和1g/L的CLDH对浓度为100mg/L的染料的脱色率分别达95.93%和99.97%.pH值是影响吸附能力的关键因素,吸附剂对溶液pH值有一定缓冲作用.LDH及CLDH对酸性黑10B吸附结果符合Langmuir吸附等温式.饱和吸附后的LDH及CLDH用高温热解法再生,吸附性能良好,随再生次数增多,脱色率下降.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
Organochlorine compounds in a three-step terrestrial food chain   总被引:1,自引:0,他引:1  
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.  相似文献   

14.
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.  相似文献   

15.
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, 240Pu, 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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
土壤中砷的化学平衡   总被引:2,自引:0,他引:2  
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。  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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