首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
生活垃圾综合处理模式生命周期评价   总被引:1,自引:0,他引:1  
陈冰  刘晶昊  邸达 《环境工程》2011,29(1):102-106
为了评价和筛选生活垃圾综合处理模式,采用生命周期模型对"分选+焚烧+填埋"、"分选+焚烧+填埋+堆肥"和"分类+焚烧+生物"3种处理模式在环境、经济等方面进行研究。结果表明:3种处理模式的环境影响潜力分别为5.92×10-2、9.11×10-2和5.09×10-2,单位处理成本为24.88、31.59和11.73元/(人.a)。经过综合评估"分类+焚烧+生物"处理模式具有明显优势。  相似文献   

2.
研究采用扩散渗析法回收草浆黑液中的氢氧化钠,分别采用了离子交换膜和上海交通大学高分子研究所提供的疏水氟膜、亲水氟膜对草浆黑液进行处理。单位膜面积单位体积黑液下阴极室总碱量的增加用R表示。三种膜的R值分别为2.17×10-7mol/(mL·cm2)、9.20×10-8mol/(mL·cm2)、4.39×10-7mol/(mL·cm2)。可见亲水氟膜的扩散渗析效果最好。实验对原黑液及经亲水氟膜扩散渗析得到的稀碱液进行了质谱分析,结果显示只有一部分小分子有机物转移到蒸馏水一侧。从亲水氟膜处理前后的扫描电镜图可以看出亲水氟膜只有较轻微的污染。可见亲水氟膜有最好的扩散渗析效果和较好的使用寿命。  相似文献   

3.
调查某厂环境汞污染致周围居民健康风险.通过对某厂周围环境介质及食物中汞含量进行测定,采用有阈化学物质健康风险评价模型,对周围2 km范围内居民健康风险进行评价.结果表明:某厂周围居民经呼吸道、消化道、皮肤汞的日均暴露量分别为0.5×10-4 mg/(kg·d)、9.35×10-5 mg/(kg·d)及2.04×10-6 mg/(kg·d),汞污染致当地居民健康风险处于可接受风险水平.某厂周围环境介质已受到一定程度的污染,但尚未影响到居民健康,由于汞的累积效应,某厂周围汞污染仍需引起关注.  相似文献   

4.
广汉市生活垃圾生命周期评价   总被引:19,自引:0,他引:19  
简要介绍了生命周期评价(LCA)的概念以及国际标准化组织1997年分布的ISO14040环境管理体系“生命周期评价原则与框架”,对城市生活垃圾的不同2方式进行了较为系统的LCA评价,结果表明,林烧,简单填埋,卫生填埋及综合处理的环境影响潜力分别为5.1×10^-2,3.8×10^-2,2.6×10^-2,和1.7×10^-2,处理成本分别为39.2元/(人.年),21.3元/(人.年),27.8元  相似文献   

5.
新农药硫肟醚在有机溶剂中的光解   总被引:16,自引:2,他引:14  
以紫外灯为光源,对硫肟醚在甲醇、丙酮、正己烷和二甲苯等有机溶剂中的光解反应动力学及降解机理进行了初步研究.结果表明,硫肟醚在4种有机溶剂中的紫外光解反应符合一级动力学规律,在4种溶剂中反应速率常数分别为1·14×10-1(正己烷)、8·90×10-2(甲醇)、2·46×10-2(二甲苯)和4·51×10-3min-1(丙酮),硫肟醚的降解半衰期分别为6·08,7·79,28·18和153·86min.通过对硫肟醚光解产物进行分离和LC-MS鉴定,初步推出在紫外光辐射下硫肟醚在有机溶剂中的降解主要涉及到硫肟醚分子的肟醚键(CNOC)断裂、甲硫键(C—S—CH3)光氧化、脱氯反应和光异构化作用等途径.  相似文献   

6.
2006年5月采集了大辽河河段3个柱状沉积物,测定了沉积物的理化性质和重金属元素的含量,并利用常规离心方法和DGT方法测定了柱状沉积物孔隙水中重金属元素的含量.研究发现沉积物中Cd、Co、Cr和Cu元素含量高低的顺序依次是Cr>Cu>Co>Cd.用DGT方法测定的孔隙水中Cd、Co、Cr和Cu的浓度比用离心方法测定的浓度要低.DGT测定的孔隙水中Cd、Co、Cr和Cu的浓度cDGT与离心方法测定的孔隙水浓度c的平均比值R分别为0.389、0.328、0.863和0.403,这说明沉积物中这几种金属从固相到液相的再补给速率大小遵循如下规律:Cr>Cu>Cd>Co.沉积物中Cd、Co、Cr和Cu元素的释放通量分别为1.12×10-7~3.28×10-7 nmol/(cm2·s)、2.48×10-7~10.40×10-7 nmol/(cm2·s)、8.80×10-6~12.65×10-6 nmol/(cm2·s)和6.14×10-6~13.93×10-6 nmol/(cm2·s).相关分析结果表明,Cd和Cu元素的迁移转化主要受有机质影响;而Cr元素的迁移转化除了受有机质影响外,还受铁锰氧化物影响比较显著;而Co元素可能受氧化还原电位影响较大.  相似文献   

7.
北京地区暖温带森林土壤温室气体排放规律   总被引:30,自引:0,他引:30  
本研究利用静态箱法在北京市东灵山暖温带森林生长期选择3种不同类型的森林(阔叶混交林、辽东栎林和油松林)的土壤进行了温室气体(CH4、CO2和N2O)排放规律的野外原位观测.研究结果表明:暖温带主要代表森林类型的土壤作为CH4的汇吸收大气中的CH4,同时作为CO2和N2O的源向大气排放.观测结果显示:不同的森林土壤类型其温室气体排放通量、范围各不相同,阔叶混交林土壤CH4、CO2和N2O通量范围分别是:42~103μg/(m2·h),15~344mg/(m2·h)和-61~101μg/(m2·h);辽东栎林土壤3种气体通量范围分别是:13~182 μg/(m2·h),23~380mg/(m2·h)和-15~183 μg/(m2·h);油松林土壤3种气体通量范围分别是:12~128 μg/(m2·h),15~292mg/(m2·h) 和 -94~153 μg/(m2·h).观测期内阔叶混交林土壤CH4、CO2和N2O平均通量分别是:-66 μg/(m2·h),145mg/(m2·h)和22 μg/(m2·h);辽东栎林土壤3种气体平均通量分别是:-67 μg/(m2·h),146mg/(m2·h)和45μg/(m2·h);油松林土壤3种气体平均通量分别是:-79 μg/(m2·h),150mg/(m2·h)和31μg/(m2·h).本研究估算了不同类型的森林土壤不同的温室气体生长期内的排放总量,阔叶混交林土壤CH4、CO2和N2O排放总量分别是:-5.34kg/(hm2·a),13.9Mg/(hm2·a) 和2.58kg/(hm2·a); 辽东栎林土壤3种气体排放总量分别是:-6.20kg/(hm2·a), 14.07Mg/(hm2·a)和4.19kg/(hm2·a); 油松林土壤3种气体排放总量分别是-6.85kg/(hm2·a), 15.71Mg/(hm2·a)和4.30kg/(hm2·a).  相似文献   

8.
生活垃圾的生命周期评价有助于改进城市垃圾管理,是减少城市生活垃圾产生的有用工具.对三门峡市城市垃圾的不同处理方式作了较为系统的生命周期评价.结果表明,卫生填埋、焚烧、综合处理的环境影响潜力分别为2.3×10-2、5.0×10-2和1.7×10-2.综合处理垃圾优于卫生填埋和焚烧两种方法.  相似文献   

9.
本文报道了新疆核试验场周围地区9个调查区17种主要食品中~(90)Sr、~(137)Cs含量分别为1.1~72.3,0.3~40.7×10~(-2)B_q·Kg~(-1);3个对照区分别为1.6~68.4,0.6~27.4×10~(-2)B_q·K_g~(-1)。两地区同类食品中~(90)Sr、~(137)Cs平均含量基本一致。调查区~(90)Sr、~(137)Cs所致成年居民有效剂量当量值分别为2μSV(集体剂量当量为30.0人· SV);0.3μSV(4.5人· SV)。对照区分别为2.2μSV(集体剂量当量为20.9人·SV);0.4μSV(3.0人·SV)。可见我国核试验产生的~(90)Sr、~(137)Cs对核试验场周围地区食品没有造成明显的局部污染,所致居民剂量当量负担仅为我国天然外照射所致年有效剂量当量(952μSV)的0.2%和0.03%。对该地区的广大居民健康不会产生有害的影响。  相似文献   

10.
应用Gabi软件,分析比较了使用厨余垃圾处理器和传统分类处理方法对城市生活垃圾处理处置全过程的生命周期评价(LCA)。研究表明,两种垃圾处理模式环境影响潜值分别为1.44×10~(-2)和1.39×10~(-2),两者的主要环境影响潜力贡献者均为全球变暖,垃圾焚烧为主要环境影响环节;厨余垃圾厌氧发酵技术主要环境影响为酸化,对全球变暖的改善效果明显;厨余垃圾粉碎直排较厌氧发酵技术对酸化的改善效果明显,但对富营养化影响增加了4×10~(-2),增加比例为22.5%,污水处理厂尾水收纳水体存在富营养化的风险。  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

13.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

14.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

15.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

16.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

17.
以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.  相似文献   

18.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

19.
Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.  相似文献   

20.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号