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281.
282.
生物质铬渣共热解工艺是新型的铬渣处理工艺,该工艺能有效地将铬渣中的Cr(Ⅵ)还原为Cr(Ⅲ).而由于共热解产物总铬含量较高,因此考察了铬渣与秸秆共热解过程中铬稳定性.通过考察共热解产物成分及形态分析、pH影响实验、淋洗实验及长期稳定性实验,对共热解铬渣的铬环境安全性进行评估.结果表明:(1)共热解温度对铬渣形态有较大影响,可交换态及碳酸盐结合态铬含量随共热解温度升高而逐渐降低,800℃时候可交换态铬降至<0.1%(质量分数,下同),碳酸盐结合态铬为1.2%;共热解后最稳定的残渣态铬含量随共热解温度升高而逐渐升高.(2)当pH>7时,两种共热解产物总铬溶出量极低,基本都小于6mg/kg;当pH≤7时,总铬的溶出量显著增加,最高超过500 mg/kg.但由于解毒铬渣的酸中和能力极强,因此铬释放风险较低.(3)共热解产物的总铬累积溶出量极低,根据拟合结果计算出其100年填埋时间的总铬溶出量不超过1.3 mg/kg.长期稳定性实验表明,自然堆置过程中共热解产物的Cr(Ⅵ)含量逐渐降低. 相似文献
283.
为探讨高效选择性回收污泥厌氧消化液中磷的离子交换方法,采用静态实验和动态实验研究了4种阴离子交换树脂(D213、D202、D301和DSQ)的磷回收性能,筛选了适合富磷污泥厌氧消化液选择性磷回收的高交换容量树脂。实验结果表明,D213、D202、D301和DSQ 4种树脂对正磷浓度为70 mg/L的厌氧消化液进行动态处理时,其最大穿透体积分别为3、7、17和90 BV;DSQ树脂磷交换容量远高于其他3种树脂,达到6 860 mg P/L湿树脂,是目前报道的高磷交换容量树脂的3~4倍;DSQ树脂能有效地抵抗厌氧消化液中有机质和硫酸根等阴离子的干扰;用NaOH溶液再生DSQ树脂并回收磷,磷洗脱率超过96%,洗脱液是高浓度含磷液,可作为磷矿石的优质替代品。研究表明,DSQ树脂是一种高效选择性分离磷的树脂,适用于污泥厌氧消化液的磷回收。 相似文献
284.
We applied the complex ecosystem model EMMO, which was adopted to the shallow lake Müggelsee (Germany), in order to evaluate a large set of ecological scenarios. By means of EMMO, 33 scenarios and 17 indicators were defined to characterize their effects on the lake ecosystem. The indicators were based on model outputs of EMMO and can be separated into biological indicators, such as chlorophyll-a and cyanobacteria, and hydro-chemical indicators, such as phosphorus. The question to be solved was, what is the ranking of the scenarios based on their characterization by these 17 indicators? And how can we handle high quantities of complex data within evaluation procedures? The scenario evaluation was performed by partial order theory which, however, did not provide a clear result. By subsequently applying the hierarchical cluster analysis (complete linkage) it was possible to reduce the data matrix to indicator and scenario representatives. Even though this step implies losses of information, it simplifies the application of partial order theory and the post processing by METEOR. METEOR is derived from partial order theory and allows the stepwise aggregation of indicators, which subsequently leads to a distinct and clear decision. In the final evaluation result the best scenario was the one which defines a minimum nutrient input and no phosphorus release from the sediment while the worst scenario is characterized by a maximum nutrient input and extensive phosphorus release from the sediment. The reasonable and comprehensive results show that the combination of partial order, cluster analysis and METEOR can handle big amounts of data in a very clear and transparent way, and therefore is ideal in the context of complex ecosystem models, like that we applied. 相似文献
285.
Robins L 《Environmental management》2008,42(5):833-846
This paper aims to give practical meaning to ‘capacity building’ through (a) identifying a suite of practical measures, such
as mentoring or best practice guidelines, that have been shown to or are considered to build human, social, institutional,
and economic capital; (b) placing these measures within a broader systems framework; and (c) exploring stakeholder feedback
on specific measures to inform framework implementation. The 29 measures described provide actors, whether government or nongovernment,
with a suite of practical investment choices for building capacity. These measures are then clustered into eight groups according
to their primary purpose and placed within a systems framework. The framework provides a tool for actors with responsibilities
for or an interest in capacity building to inform more holistic and strategic targeting of effort and investment. Stakeholder
feedback gathered through surveys and workshops is subsequently reported to further inform implementation of specific measures
within the framework’s eight groupings. The framework presented may be built upon through the identification and inclusion
of further capacity building measures. The research is conducted within the context of decentralized governance arrangements
for natural resource management (NRM), with specific focus on Australia’s recently formalized 56 NRM regions and their community-based
governing boards as an informative arena of learning. Application of the framework is explored in the Australian setting through
the identification and comparison of measures supported and most preferred by four major stakeholder groups, namely board
members, regional NRM organization staff, policy/research interests, and Indigenous interests. The research also examines
stakeholder perceptions of capacity issues, and whether these issues are likely to be addressed through implementing their
preferred measures.
相似文献
Lisa RobinsEmail: |
286.
浅谈建筑施工噪声的网络化管理 总被引:2,自引:0,他引:2
通过《南宁市环境信息综合管理系统》中建筑施工噪声管理子系统的重点研究和建设,对建设施工项目审批、中午夜间施工许可登记及施工噪声投诉实时监控,加强监督,改善了管理环节,提高了管理效能,取得了良好的效果。 相似文献
287.
An assessment of the pollution status of River Illo, located within River Owo catchments area in Ota, Ogun State, Nigeria,
was carried out. The River’s response to deoxygenation due to BOD loading from an abattoir and its dissolved oxygen (DO) level
was predicted using the modified Streeter-Phelps model. The average concentrations of measured parameters at the sampling
stations include: 2.24 mg/l of DO, 312.85 mg/l of BOD, 782.86 mg/l of chemical oxygen demand, and 620.76 g/l of total solids.
The DO model for River Illo showed a positive correlation between measured and calculated DO, while the dissolved oxygen curve
gave a double spoon shape of two major segments with distinct zones of degradation, decomposition, and recovery. The self-purification
factor (f) for both segments ranged between 0.8 and 1.1 depicting River Illo as a slow moving or sluggish river. The above results
revealed slow reaeration of the water body while full recovery from pollution was difficult. The treatment of River Illo before
usage is very essential to ensure public health safety of users from waterborne diseases. 相似文献
288.
Dryland area occupies 37% of the national territory in China. Desertification and other disasters have limited dryland sustainable development. Here we overview the dryland characteristics and desertification status and introduce four regionally optimized eco‐productive paradigms for dryland sustainable development, i.e., the mountain‐oasis paradigm in arid desert; the small watershed‐based paradigm on the Loess Plateau; the integrated animal husbandry paradigm on the Inner Mongolia Steppe and the agro‐pastoral transitional region; and three circle paradigm on the Ordos Plateau. These paradigms are established on the basis of regional landscape patterns and their underlying material and energy flow rules, and different functional belts are determined and capitalized upon with the integrated consideration of regional biogeophysical processes, biogeochemical cycles and biogeosocial relations. These paradigms cannot cover all complex landscape types, but provide theoretical frameworks and practicable models for dryland sustainable development in China. 相似文献
289.
290.
Abstract: Apparent ground‐water ages as determined by the noble gas isotope 85Kr and the water isotope 3H are compared. Refined gas extraction methodology at the wellhead permits efficient collection of Kr for 85Kr isotope enrichment. 85Kr isochrones elucidate areas of much younger ground‐water ages than 3H. Declining 3H activities in the catchment prevent its correlation with the youngest measured 85Kr ages. Source water for most drinking water supplies in the Collyer River catchment is recharged within 40 years BP (2004). Mean‐age (τ) transport modeling suggests uncertainty of ground‐water ages is greatest in the central basin area. 相似文献