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Hu X.,CAS Research Center for Eco Environmental Sciences | Zhu J.,CAS Research Center for Eco Environmental Sciences | Ding Q.,Foreign Economic Cooperation Office
Journal of Hazardous Materials | Year: 2011

Remediation action is critical for the management of polychlorinated biphenyl (PCB) contaminated sites. Dozens of remediation technologies developed internationally could be divided in two general categories incineration and non-incineration. In this paper, life cycle assessment (LCA) was carried out to study the environmental impacts of these two kinds of remediation technologies in selected PCB contaminated sites, where Infrared High Temperature Incineration (IHTI) and Base Catalyzed Decomposition (BCD) were selected as representatives of incineration and non-incineration. A combined midpoint/damage approach was adopted by using SimaPro 7.2 and IMPACTA2002+ to assess the human toxicity, ecotoxicity, climate change impact, and resource consumption from the five subsystems of IHTI and BCD technologies, respectively. It was found that the major environmental impacts through the whole lifecycle arose from energy consumption in both IHTI and BCD processes. For IHTI, primary and secondary combustion subsystem contributes more than 50% of midpoint impacts concerning with carcinogens, respiratory inorganics, respiratory organics, terrestrial ecotoxity, terrestrial acidification/eutrophication and global warming. In BCD process, the rotary kiln reactor subsystem presents the highest contribution to almost all the midpoint impacts including global warming, non-renewable energy, non-carcinogens, terrestrial ecotoxity and respiratory inorganics. In the view of midpoint impacts, the characterization values for global warming from IHTI and BCD were about 432.35 and 38.5kg CO2-eq per ton PCB-containing soils, respectively. LCA results showed that the single score of BCD environmental impact was 1468.97 Pt while IHTI's score is 2785.15 Pt, which indicates BCD potentially has a lower environmental impact than IHTI technology in the PCB contaminated soil remediation process. © 2011 Elsevier B.V. Source

Wang H.Q.,Beijing Normal University | Tian Y.H.,Beijing Normal University | Huang W.L.,Beijing Normal University | Xiao S.L.,Foreign Economic Cooperation Office
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2015

The construction of artificial grassland is the necessary way to alleviate pressures on the grassland in Inner Mongolia. Water shortage is the major limiting factor for grass growth in artificial grassland in this region. Suitable irrigation quantity is the key to solve the problem of water shortage by both increasing grass yield and saving water. In this study, we selected two local typical grasses Agropyron cristatum and Medicago sativaL and conducted irrigation experiments with single sowing and mixture sowing of the two. Then comparative analyses were explored on biomass, photosynthesis and water use efficiency of the two grasses under different irrigation schemes. The results show that: (1) The mixture sowing of leguminous herbage and gramineous herbage is helpful to enhance the yields of the two plants.; (2) Squaring period in the early August is the best season for the harvesting of Agropyron cristatum and Medicago sativaL, when the yields of the grasses are the highest; (3) Treatment 3, of which the irrigation quantity is up to 45% of the field capacity, the amount of water recharge per unit (including precipitation and irrigation) is 903.8 m3 / hm2 in early July and 1812.4 m3 / hm2 in early August, is the best water treatment choice for both grass yields increase and water-saving; (4) Rain-fed condition or irrigating a little water (treatment 3) is effective to increase long-term water use efficiency (WUEL) of the grasses from June to August. Irrigating more water (treatments 1 and 2) started to affect WUEL only after entering the flowering stage of the grasses; (5) Rain-fed condition or irrigating a little water is effective to increase grass leaf instantaneous water use efficiency (WUEI) in early August. However, because of intensive sunlight, water evaporation is high and it is more effective to increase WUEI by irrigating more water in early July. © 2015 Ecological Society of China. All rights reserved. Source

Li X.-Y.,Guizhou Normal University | Liu Y.-Q.,Foreign Economic Cooperation Office
Huanjing Kexue/Environmental Science | Year: 2013

To study the distribution of heavy metals in outdoor settled dusts in different functional areas, based on the literature published, we described the difference in heavy metal accumulation in functional areas and their sources by comparing and analyzing the data of heavy metal concentrations in some capital cities. The results showed that industrial area had the highest heavy metal concentration, followed in descending order by residential area and commercial area, and finally, traffic area. The levels of Zn and Pb in the four functional areas showed higher spatial variability, while there was little difference in Cu and Cd levels. Compared to the heavy metal concentration in urban soils, industrial area appeared heavily accumulated and traffic area appeared lighter accumulated with heavy metals, while there was little difference among other three functional areas expect industrial area. The accumulation of Cd in the four functional areas showed the lowest spatial variability. Source

Ben W.,CAS Research Center for Eco Environmental Sciences | Pan X.,Foreign Economic Cooperation Office | Qiang Z.,CAS Research Center for Eco Environmental Sciences
Environmental Sciences: Processes and Impacts | Year: 2013

Swine wastewater represents an important pollution source of antibiotics in the environment; however, regional data about residual antibiotics in swine wastewater are very limited at present. This study investigated the concentrations of three classes of commonly used veterinary antibiotics, including five sulfonamides (SAs), three tetracyclines (TCs) and one macrolide (tiamulin, TIA), in swine wastewater collected from 21 concentrated animal feeding operation (CAFO) sites in Shandong Province, China. Both the liquid and solid (i.e., suspended solids) phases of swine wastewater were analyzed to determine the total concentration of each studied antibiotic. Results indicate that sulfamethazine had the highest median concentration (14.56 μg L -1), followed by oxytetracycline (OTC, 8.05 μg L-1) and chlortetracycline (CTC, 6.01 μg L-1). The maximum detected concentration reached up to 2.02 mg L-1 (OTC) and the highest detection frequency was 95.1% (CTC). The median concentrations and detection frequencies of antibiotics in winter samples were generally higher than those in summer samples (except CTC). The log Kd values were in the range of 1.31-1.96 for SAs, 2.05-2.33 for TCs, and 1.54-1.58 for TIA in swine wastewater. More TCs (14-28%) preferred to partition in the solid phase than SAs (2-10%) and TIA (5-10%), indicating that the suspended solids of swine wastewater may not be ignored. © 2013 The Royal Society of Chemistry. Source

Zhou D.,Zhejiang University | Ren Z.,Foreign Economic Cooperation Office | Li B.,Zhejiang University | Ma Z.,Zhejiang University | And 2 more authors.
RSC Advances | Year: 2015

Hexagonal boron nitride (hBN) was used as a CuOX/TiO2 catalyst carrier and its effect on NO reduction with NH3 was studied. After hBN was treated with concentrated HNO3, CuOX/TiO2 nanoparticles were dispersed well onto hBN, and the addition of hBN was found to promote NO oxidation, while at the same time suppress NH3 oxidation to NO, and thus promoted the selective catalytic reduction of NO at reaction temperatures between 150 to 350°C, and a high de-NOX efficiency of 90.6% was achieved at 275°C. Our study indicates that hBN is a promising catalyst promoter and carrier with excellent stability compared to carbonaceous materials. © The Royal Society of Chemistry 2015. Source

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