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Municipal solid waste (MSW) landfills are potential long-term sources of emissions. Hence, they need to be managed after closure until they do not pose a threat to humans or the environment. The case study on the Breitenau MSW landfill was performed to evaluate future emission levels for this site and to illustrate the effect of final cover installation with respect to long-term environmental risks. The methodology was based on a comprehensive assessment of the state of the landfill and included analysis of monitoring data, investigations of landfilled waste, and an evaluation of containment systems. A model to estimate future emission levels was established and site-specific predictions of leachate emissions were presented based on scenario analysis. The results are used to evaluate the future pollution potential of the landfill and to compare different aftercare concepts in view of long-term emissions. As some leachable substances became available for water flow during cover construction due to a change in the water flow pattern of the waste, a substantial increase in leachate concentrations could be observed at the site (e.g. concentrations of chloride increased from 200 to 800 mg/l and of ammonia-nitrogen from 140 to about 500 mg/l). A period of intensive flushing before the final cover installation could have reduced the amount of leachable substances within the landfill body and rapidly decreased the leachate concentrations to 11 mg Cl/l and 79 mg NH4-N/l within 50 years. Contrarily, the minimization of water infiltration is associated with leachate concentrations in a high range for centuries (above 400 mg Cl/l and 200 mg NH4-N/l) with low concomitant annual emission loads (below 12 kg/year of Cl or 9 kg/year of NH4-N, respectively). However, an expected gradual decrease of barrier efficiency over time would be associated with higher emission loads of 50 kg of chloride and 30 kg of ammonia-nitrogen at the maximum, but a faster decrease of leachate concentration levels. 相似文献
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燃煤电站SCR烟气脱硝工程技术关键问题研究 总被引:6,自引:0,他引:6
对SCR烟气脱硝催化剂的选择、脱硝系统旁路设置与脱硝装置流场模拟这三个当前我国燃煤电站SCR烟气脱硝工程技术中的关键问题进行了分析与探讨,并提出了解决措施,为提高脱硝工程技术水平、完善当前SCR烟气脱硝技术规范提供借鉴。 相似文献
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Paul J. Favara Todd M. Krieger Bob Boughton Angela S. Fisher Mohit Bhargava 《补救:环境净化治理成本、技术与工艺杂志》2011,21(3):39-79
The US Sustainable Remediation Forum (SURF) proposes a nine‐step process for conducting and documenting a footprint analysis and life‐cycle assessment (LCA) for remediation projects. This guidance is designed to assist remediation practitioners in evaluating the impacts resulting from potential remediation activities so that preventable impacts can be mitigated. Each of the nine steps is flexible and scalable to a full range of remediation projects and to the tools used by remediation practitioners for quantifying environmental metrics. Two fictional case studies are presented to demonstrate how the guidance can be implemented for a range of evaluations and tools. Case‐study findings show that greater insight into a study is achieved when the nine steps are followed and additional opportunities are provided to minimize remediation project footprints and create improved sustainable remediation solutions. This guidance promotes a consistent and repeatable process in which all pertinent information is provided in a transparent manner to allow stakeholders to comprehend the intricacies and tradeoffs inherent in a footprint analysis or LCA. For these reasons, SURF recommends that this guidance be used when a footprint analysis or LCA is completed for a remediation project. © 2011 Wiley Periodicals, Inc. 相似文献
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Guang Yang Bo Yang Chao Yuan Weiwei Geng Haizhou Li 《Journal of Polymers and the Environment》2011,19(1):146-151
The effects of manufacturing parameters on mechanical properties of medium density fibreboard (MDF) bonded with modified soy
protein-based glue were studied to find an appropriate manufacture technology. Physical properties of MDF made with different
amount of wax emulsion were measured. Results indicated that water repellent had no obvious influence on physical properties
of soy protein-based MDF boards. The fiberboards bonded with soy protein-based glue showed stronger water resistance properties
than those bonded with urea–formaldehyde (UF) resins. Furthermore, the soy protein-based MDF boards had good quality [25.2%
24 h soak thickness swell (TS), 29.9 MPa modulus of rupture (MOR), 3130 MPa modulus of elasticity (MOE)], which met requirements
of Chinese national standard. Practical processing parameters were obtained by orthogonal experiment, i.e., glue content 8.0%,
hot-press temperature 200 °C, and hot-press time 150 s. 相似文献
960.
Yurong Yu Shouyi Wang Qingtao Zhang Ya Yang Ya Chen Xiangwu Liu 《Journal of environmental science and health. Part. B》2019,54(2):89-97
A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2–5.5?days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005–0.120?mg kg?1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields. 相似文献