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1.
城市生活垃圾、污泥和煤粉混合燃料热值的研究   总被引:3,自引:1,他引:2  
为了寻求生活垃圾和污泥的高效资源化、能源化方法.选取生活垃圾、污泥和煤粉的混合,枯枝落叶,助燃剂MnO2,脱硫剂 CaO 为控制因子,安排正交试验,成型加工为混合燃料.测定其热值,并通过正交分析,筛选出燃料最大热值组合,即混合时垃圾、污泥、煤粉的比例为 1:1:2,枯枝落叶所占比例为 0%,助燃剂 MnO2 含量为 0.18%,脱硫剂 CaO 含量为 1.5/(100 g),该燃料的热值为 17.8898 kJ/g.为该混合燃料的推广与应用提供理论依据.  相似文献   

2.
城市污水厂污水污泥的热值测定分析方法研究   总被引:4,自引:3,他引:1  
高旭  马蜀  郭劲松  范莹 《环境工程学报》2009,3(11):1938-1942
建立热力学指标是污水生物处理过程热力学分析的基础工作,目前仍缺乏污水污泥化学能测试的标准方法。采用IKA C5000型自动热量计对某城市二级污水处理厂进水、出水、初沉污泥、剩余污泥、混合污泥和脱水污泥进行了热值测定,样品前处理采用103~105℃烘干获得干燥基,用苯甲酸进行加标回收。参照煤的发热量测定方法得到样品的高位热值。试验结果显示:出水干燥基的热值为05 kJ/g,进水干燥基的热值为4 kJ/g以上,各工艺段的污泥干燥基热值较高,基本都在12 kJ/g以上,接近右江褐煤水平。测定结果的标准偏差≤±0.452%,相对标准偏差≤±0.136%。通过同一批样品的元素分析及Dulong公式理论推算,发现2种方法可得到相似的结果。  相似文献   

3.
污水处理厂污泥的再利用集成技术   总被引:3,自引:0,他引:3  
将武汉市污水处理厂的剩余活性污泥在不同pH、不同时间下水解,测定水解液的蛋白质含量、重金属离子含量、氨基酸的种类及含量;将水解液制备成蛋白质泡沫灭火剂并测定其灭火参数;将所剩残渣干燥并测定热值,按5%的比例与煤混合压制成蜂窝煤,并测定热值。实验表明,所制备灭火剂的各项指标符合国家标准,所制备蜂窝煤减少了黄泥的使用,增强了蜂窝煤的热值,燃烧试验证明是完全可行的,该集成技术可实现污泥减量化、无害化和资源化利用。  相似文献   

4.
含油污泥燃料化处理剂研制及其作用机理研究   总被引:4,自引:1,他引:3  
含油污泥主要有清罐油泥(罐底泥)、隔油池底泥、污水处理厂浮渣以及剩余活性污泥等几类.含油污泥含有油、苯系物、酚类、蒽、芘等具有恶臭味和毒性的物质,是国家明文规定的危险废弃物.另一方面,含油污泥中富含大量烃类,潜在能量大,热值高,平均热值达5 000kcal/kg以上.经大量室内实验,开发了一种新型含油污泥燃料化处理剂,...  相似文献   

5.
污水处理厂污泥的再利用集成技术   总被引:2,自引:0,他引:2  
将武汉市污水处理厂的剩余活性污泥在不同pH、不同时间下水解,测定水解液的蛋白质含量、重金属离子含量、氨基酸的种类及含量;将水解液制备成蛋白质泡沫灭火剂并测定其灭火参数;将所剩残渣干燥并测定热值,按5%的比例与煤混合压制成蜂窝煤,并测定热值。实验表明,所制备灭火剂的各项指标符合国家标准,所制备蜂窝煤减少了黄泥的使用,增强了蜂窝煤的热值,燃烧试验证明是完全可行的,该集成技术可实现污泥减量化、无害化和资源化利用。  相似文献   

6.
对剩余污泥进行厌氧发酵处理可实现污泥中有机质和磷的释放并最终回收利用,而pH是影响厌氧发酵过程的重要因子。为研究pH对厌氧发酵中磷与有机物释放的影响,采用批次实验研究了pH分别为3、5、7、9、10、11时剩余污泥厌氧发酵过程中磷和有机物的释放与转化规律。结果表明,在不同pH下,剩余污泥厌氧发酵过程中发生着有机物与不同形态磷的迁移与转化,酸性和碱性环境下的厌氧发酵液成分的三维荧光结构不同。剩余污泥厌氧发酵过程中,泥相钙结合态磷(AP)在酸性条件下转化为液相磷,有机磷(OP)和大部分铁/铝结合态磷(NAIP)在碱性条件下转化为液相磷;其中, pH为11时,污泥发酵液中磷含量最高。污泥发酵类型为丁酸型发酵,发酵产物以异丁酸为主,其次是正戊酸和乙酸。pH为10时,发酵液中的蛋白质与多糖的总量、挥发性有机酸(VFAs)浓度最高,两者呈现正相关关系;类蛋白和类腐殖酸降解,利于VFAs的积累。  相似文献   

7.
污泥水解酸化过程中污染物的释出及其影响因素研究   总被引:4,自引:1,他引:3  
刘爽  袁林江  王振 《环境工程学报》2009,3(7):1316-1320
为了回收利用污泥中的有机物、氮和磷,研究了将厌氧污泥接种到吸附了污染物质的剩余污泥中,对污泥水解酸化的促进以及污泥中微生物所摄取污染物质的释出规律;揭示了厌氧条件下发酵时间、污泥量、pH和热处理对污染物释出的影响。结果表明,接种24 h后污染物被大量释放出来;在发酵时间为24 h条件下,污染物释出量与污泥质量成正比;吸附了污染物的剩余污泥相对含量越高,释磷量越大;污泥厌氧发酵时,碱性条件下有机物和正磷酸盐的释出量大于酸性条件,加碱调高pH可有效促进氨氮的释出;对吸附了污染物的剩余污泥进行短时热处理可有效缩短其厌氧发酵时污染物的释出时间。结果表明,控制污泥厌氧水解发酵条件可以促进污染物的释出,有利于下一步的回收。  相似文献   

8.
通过正交实验考察了异噻唑啉酮耦合氧化钙对压滤污泥含水率、燃烧热值、Zeta电位和泥饼含硫量的影响,结果表明,各因素对污泥含水率影响的大小顺序依次为:氧化钙投加量、压强、压滤时间、异噻唑啉酮投加量;各因素对污泥燃烧热值影响的大小顺序依次为:氧化钙投加量、压滤时间、异噻唑啉酮投加量和压强。异噻唑啉酮投加量为5.6 mg/g TSS,氧化钙投加量为120 mg/g TSS,压强为0.40 MPa,压滤时间为1 h条件下,污泥含水率为55.5%,105℃烘干泥饼的热值为10 702 J/g,Zeta电位值为-30.082 mV,泥饼含硫量为0.408%。此时污泥含水率较低,热值较高,含硫量较低,有利于污泥的焚烧处理。  相似文献   

9.
水泥窑协同处置含油污泥   总被引:2,自引:0,他引:2  
含油污泥是石油石化生产过程中产生的一种含油固体废弃物,现有的含油污泥处理技术主要解决了油泥中油气资源的部分回收,未实现油泥的彻底无害化。采用能谱仪、原子荧光光度计和等离子体发射光谱仪等检测手段,检测了不同油田含油污泥的成分、热值及重金属含量,并与水泥生产的相关标准进行了对比分析。结果表明,含油污泥灰分中氧化钙、氧化硅等含量总和均大于80%;灰分中重金属含量基本满足《水泥工厂设计规范》GB50295-2008中水泥熟料重金属含量要求,可作为水泥生产的替代原料。采集的各油田含油污泥平均热值达17.6 MJ/kg,大部分含油污泥都可以作为水泥生产的替代燃料。同时,水泥窑协同处置含油污泥时有害有机物被彻底分解,不会产生二次污染,能真正实现含油污泥的减量化、资源化和无害化,是一项值得推广的处置方式。  相似文献   

10.
污泥中含有大量的有机物、重金属以及病原菌等,不加处理任意排放会对环境造成严重的污染.以中国矿业大学(南湖校区)污水处理厂剩余污泥为研究对象,通过堆肥实验以及堆肥农用的盆栽实验得出,污泥堆肥整体上可以降低污泥中重金属和有机质的含量,TN含量在堆肥过程中先增加但最终下降,TP含量在堆肥过程中有所增加;污泥堆肥农用后,随着堆肥施用量的增加,土壤和小麦中的重金属含量有所增加;土壤中的有机质、TN和TP含量也有所增加;当小麦长势最好时,有机质比空白样增加了27.6%,TP增加了232.4%,TN增加了213.5%;从有机质和TN角度看,污泥堆肥施用量大于20 t/hm2时,土壤肥力达到高肥标准.  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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