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621.
钟钢  曹丽君  贾玮 《四川环境》2010,29(5):82-86
通过对工业园区低碳发展模式的评估,分析其低碳发展的能源特征、经济特征与人力特征,并确定工业园区二氧化碳减排的潜力能源。基于能源-碳减排(EC)、经济-能源-碳减排(EEC)和人力-经济-能源-碳减排(HEEC)三种不同情景,在未来发展的一定规划期内,对工业园区具有二氧化碳减排潜力的能源进行规划分析,确定其年递减率,从而实现工业园区不同情景下的二氧化碳减排。通过实际案例研究,证明了评估与规划分析模型的可行性。  相似文献   
622.
油田作业废水处理技术研究进展   总被引:3,自引:2,他引:1  
文章讨论了作业废水的组成与特点,并对近年来钻井废水处理工艺,酸化废水处理工艺,压裂废水处理工艺进行了总结与评述。根据作业废水的处理现状,对未来作业废水的处理技术进行了展望。油田废水处理主要向以下三个方面发展:开发新型处理药剂;建立高效处理工艺流程;从污水源头开始控制。  相似文献   
623.
Anthropogenic Pu isotopes are important geochemical tracers for sediment studies. Their distributions and sources in the water columns as well as the sediments of the North Pacific have been intensively studied; however, information about Pu in the Southeast Asian seas is limited. To study the isotopic composition of Pu, and thus to identify its sources, we collected sediment core samples in the South China Sea and the Sulu Sea during the KH-96-5 Cruise of the R/V Hakuho Maru. We analysed the activities of 239+240Pu and the atom ratios of 240Pu/239Pu using isotope dilution sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS). The 240Pu/239Pu atom ratios in the sediments of both areas (inventory weighted mean: 0.251 for the South China Sea and 0.280 for the Sulu Sea) were higher than the global fallout value (0.178 ± 0.019), suggesting the existence of Pu from the Pacific Proving Grounds in the North Pacific. Low inventories of 239+240Pu in sediments were observed in the South China Sea (3.75 Bq/m2) and the Sulu Sea (1.38 Bq/m2). Most of the Pu input is still present in the water column. Scavenging and benthic mixing processes were considered to be the main processes controlling the distribution of Pu in the deep-sea sediments of both study areas.  相似文献   
624.
The different barks were sampled to discuss the influence of the tree species, trunk circumference, and bark thickness on the accumulation processes of polybrominated diphenyl ethers (PBDEs) from air into the bark. The results of different PBDE concentrations indicated that barks with a thickness of 0–3 mm collected from weeping willow, Camphor tree, and Masson pine, the trunk circumferences of which were 100 to 150 cm, were better PBDEs passive samplers. Furthermore, tree bark and the corresponding air samples were collected at Anji (AJ), Hangzhou (HZ), Shanghai (SH), and Wenling (WL) to investigate the relationship between the PBDE concentrations in bark and those in air. In addition, the significant correlation (r 2?=?0.906; P?<?0.05) indicated that atmospheric PBDEs were the principle source for the accumulation of PBDEs in the barks. In this study, the log K BA (bark–air partition coefficient) of individual PBDE congeners at the four sites were in the range from 5.69 to 6.79. Finally, the total PBDE concentration in WL was 5 to 20 times higher than in the other three cities. The result indicated that crude household workshops contributed a heavy amount of PBDEs pollution to the environment, which had been verified by the spatial distribution of PBDEs levels in barks collected at Wenling (range, 26.53–1317.68 ng/g dw). The good correlation between the PBDE concentrations in the barks and the air samples and the variations of the PBDE concentrations in tree barks collected from different sites reflected that the bark could be used as a passive sampler to indicate the atmospheric PBDEs.  相似文献   
625.
Various hazardous substances contained in waste TV sets might be released into environment via dust during recycling activities. Two brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), and tetrabromobisphenol A (TBBPA), and five kinds of heavy metals (Cu, Pb, Cd, Cr, and Ni) were detected in indoor dust collected from two workshops (TV dismantling workshop and subsequent recycling workshop). PBDEs concentrations in dust from waste wires recycling line (722,000 ng/g) were the highest among the studied sites, followed by those in manual dismantling–sorting line (117,000 ng/g), whereas TBBPA concentrations were the highest in manual dismantling–sorting line (557 ng/g) and printed circuit board (PCB) recycling line (428 ng/g). For heavy metals, Cu and Pb were the most enriched metals in all dust samples. The highest concentration of Pb (22,900 mg/kg) was found in TV dismantling workshop-floor dust. Meanwhile, Cu was the predominant metal in dust from the PCB recycling line, especially in dust collected from electrostatic separation area (42,700 mg/kg). Occupational exposure assessment results showed that workers were the most exposed to BDE-209 among the four PBDE congeners (BDE-47, BDE-99, BDE-153, and BDE-209) in both workshops. The hazard quotient (HQ) indicated that noncancerous effects were unlikely for both BFRs and heavy metals (HQ?<?1), and carcinogenic risks for Cd, Cr, and Ni (risk?<?10?6) on workers in two workshops were relatively low.  相似文献   
626.
Elsholtzia splendens is a copper-tolerant plant species which grows on copper deposits in China. The generation of a valuable E. splendens biomass on specific contaminated sites has become one of the promising phytotechnologies. The simultaneous separations of apigenin, luteolin, and rosmarinic acid yielded in the ethyl acetate extracts of the flowering aerial parts was achieved by the use of a macroporous resin, polyamide, and silicagel columns during chromatography. Chemical identification confirmed the structures based on the spectra of FTIR, NMR, and HPLC/ESI-MS. The isolated compounds of purity above 98.3 % were evaluated for their in vitro cytotoxic activities against human cancer cell lines including A549 (non-small lung), A431 (skin), and Bcap37 (breast). Among these compounds, luteolin and apigenin presented the best cytotoxic activities against A549, A431, and Bcap37 cells and, therefore, both could be the valuable products for the post-harvest processing of E. splendens biomass.  相似文献   
627.
镍基催化剂对污泥微波热解制生物气效能的影响   总被引:1,自引:0,他引:1  
为实现污水污泥减量化、无害化及资源化的目标,在微波热解污水污泥基础上,进行了镍基催化剂对制取生物气效能影响的研究。采用元素分析对污泥元素进行检测,气/质联用分析(GC-MS)和气相色谱(GC)对热解生物气的组成和含量进行测定。实验结果表明,镍基催化剂的添加对微波热解污水污泥制取生物气有较大促进作用。5%添加量与800℃热解终温条件下具有最佳催化效果:生物气中H2、CO产量最大,H2产量由29 g/kg增加到35.8 g/kg,提升23.4%,CO产量由302.7 g/kg增加到383.3 g/kg,提升26.6%;同时催化剂还能提高热能利用效率,降低热解终温,即5%添加量在700℃热解终温时可达到空白800℃时的产气效果;镍基催化剂主要在500~600℃时发挥催化作用,加快了H2和CO的释放。微波热解污泥制取的生物气具有产量大、富含H2与CO等优点,可推动污水污泥的资源化进程。  相似文献   
628.
运用Gambit软件建立了污泥好氧发酵堆体的多孔介质模型,通过自行设计的实验装置获得了堆体的通风粘性阻力系数和惯性阻力系数以及功能膜压差与透气量之间的关系,用Fluent软件分析了堆体不同截面形状及底部通风管数量对堆体通风均匀性的影响,为确定合理的通风管数量及截面几何形状提供理论依据。对上海奉贤区城镇污水厂污泥处理工程发酵仓进行堆体流场模拟,确定堆体采用小拱形截面形状,堆高2 m,宽8 m,底部设置4条通风管,实际运行效果良好。  相似文献   
629.
以白碳黑、硅灰、硅藻土和硅胶筛选硅质原料,并与钙质原料电石渣制备了水化硅酸钙。借助XRF、BET、FTIR等表征手段,通过多次重复除磷实验,研究了硅质原料特性对水化硅酸钙回收磷性能的影响。结果表明,白碳黑具有极高的反应活性,因此可作为制备具有磷回收特性的水化硅酸钙的硅质原料。结合XRD等表征发现,白碳黑的有效利用率是影响水化硅酸钙回收磷性能的关键,该利用率取决于白碳黑与电石渣的摩尔配比以及水热反应温度。当电石渣与白碳黑的摩尔比为1.6:1,反应温度为170℃时,白碳黑具有最佳的利用效率。该条件制备的水化硅酸钙可作为晶种,在其表面结晶形成羟基磷灰石,从而达到磷回收的目的,磷回收后固体物质中的磷含量为19.05%。  相似文献   
630.
Ni2 +对活性污泥活性及群落多样性的影响   总被引:1,自引:0,他引:1  
通过检测活性污泥的电子传递体系活性以及生物多样性,研究Ni2+对活性污泥微生物活性及群落多样性的影响。结果表明:与对照系统相比,5 mg/L的Ni2+对2,3,5-triphenylteltrazolium chloride(TTC-ETS)活性未产生显著的影响;但当Ni2+的浓度进一步增大到10、20和40 mg/L后,其对序批式反应器内活性污泥TTC-ETS活性的抑制率分别达到(36.79±11.14)%、(55.88±13.90)%和(70.97±6.78)%。低浓度Ni2+能增强活性污泥微生物对碳源的利用,但高于10 mg/L的Ni2+则显著抑制了活性污泥微生物对碳源的利用。各个SBR系统中微生物群落最常见的物种相近,物种丰富度和均一性则均有所不同,其中群落物种丰富度随着Ni2+浓度的增加而逐渐减小。TTC-ETS活性、平均每孔颜色变化率、Shannon指数和Simpson指数,与Ni2+的胁迫浓度之间的显著相关性表明,它们均可有效地表征Ni2+胁迫对活性污泥微生物活性及群落多样性的影响程度。  相似文献   
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