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671.
通过模拟油田采出液,考察了油水比、聚合物、表面活性剂及天然固体颗粒物对油田采出液乳化程度的影响。试验表明:随着油水比下降,模拟水样含油量降低,油珠Zeta电位升高,平均粒径变大,水样乳化稳定性减弱;HPAM会吸附于油珠表面从而增强其负电性,降低油珠间的有效碰撞,使油珠的平均粒径较小,导致油水分离较困难;表面活性剂会直接降低水样的表面张力,增强油水亲和性,导致水样含油量增大,同时增强了油珠的负电性,不利于油珠的集结聚并;天然固体颗粒物本身有一定的电负性,降低了油珠的Zeta电位,增加油珠的静电排斥,妨碍油珠的聚并,同时使水样的含油量升高,最终导致乳状液稳定。  相似文献   
672.
本研究构建了厌氧膜生物反应器(AnMBR)-部分亚硝化/厌氧氨氧化(PN/Anammox)污水处理工艺,以探究AnMBR-PN/A工艺处理效果最佳的水力停留时间(HRT).AnMBR将厌氧生物处理与膜分离技术相结合实现有机物去除,AnMBR出水NH4+-N通过PN部分转化为NO2--N,最终通过NO2--N氧化剩余NH4+-N去除.实验结果表明:在HRT=11.2 h时,AnMBR-PN/A工艺化学需氧量(COD)去除率稳定在97%以上,COD转化为CH4效率超过77.5%,总氮(TN)去除率为78%,出水COD和TN浓度分别低于14和11 mg·L-1.AnMBR段COD去除率达到95%,平均甲烷产率为0.39 L·L-1·d-1.PN段实现了NO2--N的高效积累,其出水中NO2-/NH4+为0.91±0.11.Anammox段出水中的NO2--N、NH4+-N和NO3--N浓度分别低于1.0、4.9和5.1 mg·L-1.高通量测序结果表明PN段氨氧化菌主要为Nitrosomonas,丰度为7.09%,Anammox段主要微生物为Candidatus Brocadia,丰度高达21.01%.本研究构建的AnMBR-PN/A工艺实现了污水处理过程的高效能源回收和深度自养脱氮,研究成果为工程应用提供了理论支撑.  相似文献   
673.
Bioelectrochemical systems (BES) have been extensively studied for resource recovery from wastewater. By taking advantage of interactions between microorganisms and electrodes, BES can accomplish wastewater treatment while simultaneously recovering various resources including nutrients, energy and water (“NEW”). Despite much progress in laboratory studies, BES have not been advanced to practical applications. This paper aims to provide some subjective opinions and a concise discussion of several key challenges in BES-based resource recovery and help identify the potential application niches that may guide further technological development. In addition to further increasing recovery efficiency, it is also important to have more focus on the applications of the recovered resources such as how to use the harvested electricity and gaseous energy and how to separate the recovered nutrients in an energy-efficient way. A change in mindset for energy performance of BES is necessary to understand overall energy production and consumption. Scaling up BES can go through laboratory scale, transitional scale, and then pilot scale. Using functions as driving forces for BES research and development will better guide the investment of efforts.
  相似文献   
674.
Analysis of collection and recycling system of end-of-life batteries was examined. Relatively limited fractions of portable batteries were collected by EPR system. More effective and diverse collection pathways should be developed. Consumers increasingly have worn-out batteries as electrical and electronic equipment with new technical developments are introduced into the market and quickly replace older models. As a result, large amounts of end-of-life (EOL) or waste batteries are generated. Such batteries may contain a variety of materials that includes valuable resources as well as toxic elements. Thus, the proper recycling and management of batteries is very important from the perspective of resource conservation and environmental effect. The collection and recycling of EOL batteries is relatively low in South Korea compared to other countries, although an extended producer responsibility (EPR) policy was adopted for battery recycling in 2003. In this study, the management and material flow of EOL batteries is presented to determine potential problems and quantitative flow, based on literature review, site visits to battery recycling facilities, and interviews with experts in the Korea Battery Recycling Association (KBRA), manufacturers, and regulators in government. The results show that approximately 558 tons of manganese-alkaline batteries, the largest fraction among recycling target items, was disposed in landfills or incinerators in 2015, while approximately 2,000 tons of batteries were recovered at a recycling facility by simple sorting and crushing processes. By raising environmental awareness, more diverse and effective collection systems could be established for consumers to easily dispose of EOL batteries in many places. Producers, retailers and distributors in South Korea should also play an important role in the collection of EOL batteries from consumers. Lithium-ion batteries from many electronic devices must be included in the EPR system for resource recovery.  相似文献   
675.
• Powdered resin was employed for ammonia recovery from municipal wastewater. • Powdered resin achievedefficient ammonia removal under various working conditions. • Co-existing cations indicated competitive adsorption of ammonia. • Ammonia was recoveredby two-stage crystallization coupled with ion exchange. Low-strength municipal wastewater is considered to be a recoverable nutrient resource with economic and environmental benefits. Thus, various technologies for nutrient removal and recovery have been developed. In this paper, powdered ion exchange resin was employed for ammonia removal and recovery from imitated low-strength municipal wastewater. The effects of various working conditions (powdered resin dosage, initial concentration, and pH value) were studied in batch experiments to investigate the feasibility of the approach and to achieve performance optimization. The maximum adsorption capacity determined by the Langmuir model was 44.39 mg/g, which is comparable to traditional ion exchange resin. Further, the effects of co-existing cations (Ca2+, Mg2+, K+) were studied. Based on the above experiments, recovery of ammonia as struvite was successfully achieved by a proposed two-stage crystallization process coupled with a powdered resin ion exchange process. Scanning electron microscopy (SEM) and X-ray diffractometry (XRD) results revealed that struvite crystals were successfully gained in alkaline conditions (pH= 10). This research demonstrates that a powdered resin and two-stage crystallization process provide an innovative and promising means for highly efficient and easy recovery from low-strength municipal wastewater.  相似文献   
676.
铜镍电镀退镀废液资源化处理工艺   总被引:3,自引:0,他引:3  
针对硝酸型铜镍退镀废液,确定了蒸馏法回收硝酸、溶剂萃取法分离提取铜、沉淀分离法回收镍的工艺路线.探讨了采用P507煤油体系萃取分离硝酸介质中的铜和镍及用硫酸反萃铜的条件及影响规律,确定了最佳工艺参数.结果表明,硝酸回收率可达97.8%;当最佳萃取工艺条件为:料液浓度Cu 15~20mg/mL,Ni 5~10 mg/mL,料液pH为1~2,萃取剂体积分数35%,皂化度60%,相比为1∶1,振荡时间2min,温度20℃~25℃,铜的一级萃取率达90%以上,铜镍分离系数为75,经过三级逆流萃取废液中的铜镍已达到完全分离;以NaOH作沉淀剂,溶液的pH为10~11,镍的回收率可达99.9%.经上述处理后,使排放液达到国家工业废水排放标准要求.  相似文献   
677.
People experiencing homelessness are vulnerable to extreme weather in unique ways. The entrenched inequalities that underpin disaster vulnerability are compounded by extreme isolation and the stress of transient living on mental and physical health. However, the impacts of extreme weather on the homeless in Australia are largely undocumented and rarely incorporated in emergency planning. Interviews with and surveys of emergency and homeless services and service users revealed that the primary ramifications of losing shelter and worsening mental health deepen the cycle of homelessness and trauma. Consequently, homeless shelter losses, such as tents, should be included in pre‐ and post‐event impact statistics and subsequent recovery support. Extreme weather response plans should include early triggers and strategies for ‘non‐severe’ weather events, as the homeless community is affected earlier and by a wider range of meteorological conditions. Moreover, this study also explores the benefits of a trauma‐informed response to extreme weather when working with the homeless.  相似文献   
678.
Helen Young  Musa Adam Ismail 《Disasters》2019,43(Z3):S318-S344
Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.  相似文献   
679.
Disaster recovery is a dynamic process of creating, maintaining, and changing the meaningful context of survivors. It is completed when they redevelop their self‐reliance and resume managing their social relations with a sense of community. This study employed action research to examine how researchers and survivors collaborated to change disaster recovery through the generative power of metaphor in a small village in Japan that experienced the Niigata–Chuetsu earthquake on 23 October 2004. It outlines long‐term collaborative practices as survivors undertook new activities owing to the power of the metaphor of ‘school’. Once ‘school’ was adopted as the metaphor for where survivors learnt new skills and passed on traditional knowledge, they created new metaphors and performed new activities independently, which is critical for recovery as it demonstrates self‐reliance. The paper assesses the reasons why generative metaphors worked effectively in this case and highlights some academic and practical implications for disaster recovery.  相似文献   
680.
Home buyout programs facilitate the permanent relocation of residents away from areas considered to be at risk from future hazards, though few studies have examined the impacts of home buyout programs on affected households and communities beyond the program implementation period. In this paper, we examine between-neighborhood variation in key recovery indicators for three neighborhoods that followed different paths to recovery after Hurricane Sandy: one that rebuilt in situ, one that participated in a buyout and relocated, and one located immediately adjacent to the buyout zone. Three years post-disaster, buyout participants are faring worse in terms of place attachment and social capital compared to residents in the other two neighborhoods, while the neighborhood adjacent to the buyout zone is also showing signs of decline. These findings suggest that the social costs of buyouts extend well into the recovery period, and that the place-based ties and social networks that would typically help individuals cope with disaster impacts and persevere through adversity may be diminished for buyout participants, ultimately hindering their recovery. We conclude with a discussion of the implications of buyouts on participating and affected communities, as well as implications for research and policy.  相似文献   
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