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1.
R G Feachem 《Proceedings of the Royal Society of London. Series B, Containing papers of a Biological character. Royal Society (Great Britain)》1980,209(1174):15-29
The International Drinking Water Supply and Sanitation Decade (1981-90) is almost upon us. During this period, massive international efforts will be made to accelerate the provision of domestic water supply and sanitation facilities for the rural population of developing countries. Certain concepts and approaches are being developed and promoted as guiding themes that will help to steer and coordinate the activities of the Decade. Among them are 'appropriate technology' 'community participation' and a 'village level' or 'user-choice' approach. The validity and importance of these concepts are discussed. It is concluded that these concepts are often applied in an over-simplified manner and that they divert attention away from the fundamental political and administrative realities that primarily determine the success or failure of rural water and sanitation programmes. 相似文献
2.
Although practiced for more than 7 millennia, the landfill disposal of refuse has, as yet, with few exceptions, been merely regarded as a low-cost disposal option and its exploitation potential has been largely ignored. Today, however, a number of possibilities are under consideration including the production of energy, chemical feedstock, value-added chemicals, carbon dioxide and protein; the use of refuse as an anaerobic filter for the co-disposal of industrial wastewater and sludge; and the restoration of impoverished soils by fresh or composted refuse addition. Development of these technologies, however, necessitates a comprehensive understanding of the fundamental microbiology and biochemistry of refuse catabolism. Existing fundamental knowledge underpinning these technologies will be considered in a series of review articles. In the first, control/exploitation of the solid-state refuse methanogenic fermentation is examined with specific reference to the effects of first-tier variable manipulations. 相似文献
3.
Katukiza AY Ronteltap M Niwagaba CB Foppen JW Kansiime F Lens PN 《Biotechnology advances》2012,30(5):964-978
Poor sanitation in urban slums results in increased prevalence of diseases and pollution of the environment. Excreta, grey water and solid wastes are the major contributors to the pollution load into the slum environment and pose a risk to public health. The high rates of urbanization and population growth, poor accessibility and lack of legal status in urban slums make it difficult to improve their level of sanitation. New approaches may help to achieve the sanitation target of the Millennium Development Goal (MDG) 7; ensuring environmental sustainability. This paper reviews the characteristics of waste streams and the potential treatment processes and technologies that can be adopted and applied in urban slums in a sustainable way. Resource recovery oriented technologies minimise health risks and negative environmental impacts. In particular, there has been increasing recognition of the potential of anaerobic co-digestion for treatment of excreta and organic solid waste for energy recovery as an alternative to composting. Soil and sand filters have also been found suitable for removal of organic matter, pathogens, nutrients and micro-pollutants from grey water. 相似文献
4.
- Preamble. This series of two papers analyses and compares the environmental loads of different water production technologies
in order to establish, in a global, rigorous and objective way, the less aggressive technology for the environment with the
present state of the art of technology. Further, an estimation of the potential environmental loads that the considered technologies
could provoke in future is also presented, taking into account the most suitable evolution of the technology.
- Part 1 presents the assessment of most commercial desalination technologies which are spread worldwide: Reverse Osmosis, Multi
Effect Desalination and Multi Stage Flash.
Part 2 presents the comparative LCA analysis of a big hydraulic infrastructure, as is to be found in the Ebro River Water
Transfer project, with respect to desalination.
- Intention, Goal and Background. In this paper some relevant results of a research work are presented, the main aim of which
consists of performing the environmental assessment of different water production technologies in order to establish, in a
global, rigorous and objective way, the less aggressive technology for the environment for supplying potable water to the
end users. The scope of this paper is mostly oriented to the comparative Life Cycle Assessment of different water production
technologies instead of presenting new advancements in the LCA methodology. Based on the results obtained in Part 1 (LCA of
most widespread commercial desalination technologies), the particular case of a big hydraulic project, which is the Ebro River
Water Transfer (ERWT) considered in the Spanish National Hydrologic Plan, versus the production by desalination of the same
amount of water to be diverted, is compared in Part 2. The assessment technique is the Life Cycle Analysis (LCA), which includes
the entire life cycle of each technology, encompassing: extraction and processing raw materials, manufacturing, transportation
and distribution, operation and final waste disposal.
Methods and Main Features. The software SimaPro 5.0, developed by Dutch PRé Consultants, has been used as the analysis tool, because
it is a well known, internationally accepted and validated tool. Different evaluation methods have been applied in the LCA
evaluation: CML 2 baseline 2000, Eco-Points 97 and Eco-Indicator 99. Data used in the inventory analysis of this Part 2 come
from: a) desalination: data obtained for existing plants in operation; b) ERWT: Project approved in the Spanish National Hydrologic
Plan and its Environmental Impact Evaluation and; c) data bases implemented in the SimaPro software – BUWAL 250, ETH-ESU 96,
IDEMAT 2001. Different scenarios have been analyzed in both parts in order to estimate not only the potential of reduction
of the provoked environmental loads with the present state of the art of technology, but also the most likely future trend
of technological evolution. In Part 1, different energy production models and the integration of desalination with other productive
processes are studied, while the effect of the most likely technological evolution in the midterm, and the estimation of the
environmental loads to the water transfer during drought periods are considered in Part 2.
Results and Discussion As proven in Part 1, RO is a less aggressive desalination technology for the environment. Its aggression is one order of
magnitude lower than that of the thermal processes, MSF and MED. The main contribution to the global environmental impact
of RO comes from the operation, while the other phases, construction and disposal, are almost negligible when compared to
it. In the case of the ERWT, the contribution of the operation phase is also the most important one, but the construction
phase has an important contribution too. Its corresponding environmental load, with the present state of the art of technology,
is slightly lower than that provoked by the RO desalination technology. However, the results obtained in the different scenarios
analyzed show that the potential reduction of the environmental load in the case of the ERWT is significantly lower than that
in the case of the RO. The effect of drought periods in the assessed environmental loads of the water transfer is not negligible,
obtaining as a result an increasing environmental load per m3 of diverted water.
Conclusion The environmental load associated with RO, with the present state of the art of technology, is slightly higher than that
provoked by the ERWT. However, considering the actual trend of technological improvement of the RO and the present trend of
energy production technology in the address of reducing the fossil fuels\ contribution in the electricity production, the
environmental load associated with RO in the short mid-term would be likely to be lower than that corresponding to the ERWT.
Recommendations and Outlook Although desalination technologies are energy intensive and provoke an important environmental load, as already explained
in Part 1, they present a high potential of reducing it. In respect to ERWT, the results indicate, when the infrastructure
of ERWT is completed (by 2010–2012), that the LCA of RO will be likely to be against the water transfer. With the present
technological evolution of water production technologies and from the results obtained in this paper, it seems, from an environmental
viewpoint, that big hydraulic projects should be considered the last option because they are rigid and long-term infrastructures
(several decades and even centuries of operation) that provoke important environmental loads with only a small margin for
reducing them. 相似文献
5.
- Preamble. This series of two papers analyses and compares the environmental loads of different water production technologies in order to establish, in a global, rigorous and objective way, the less aggressive technology for the environment with the present state of the art of the technology. Further, it is also presented an estimation of the potential environmental loads that the considered technologies could provoke in future, taking into account the most suitable evolution of the technology. - Part 1 presents the assessment of most commercial desalination technologies which are spread worldwide: Reverse Osmosis, Multi Effect Desalination and Multi Stage Flash.
Part 2 presents the comparative LCA analysis of a big hydraulic infrastructure, as is to be found in the Ebro River Water Transfer project, with respect to desalination. - DOI: http://dx.doi.org/10.1065/lca2004.09.179.1 - Intention, Goal and Background. In this paper, some relevant results of a research work are presented, the main aim of which consists of performing the environmental assessment of different water production technologies in order to establish, in a global, rigorous and objective way, the less aggressive technology for the environment of potable water supply to the end users. That is, the scope of this paper is mostly oriented to the comparative Life Cycle Assessment of different water production technologies instead of presenting new advancements in the LCA methodology. In Part 1, the environmental loads associated with the most widespread and important commercial desalination technologies all over the world - Reverse Osmosis (RO), Multi Effect Desalination (MED) and Multi Stage Flash (MSF) are compared. The assessment technique is the Life Cycle Analysis (LCA), which includes the entire life cycle of each technology, encompassing: extraction and processing raw materials, manufacturing, transportation and distribution, operation and final waste disposal.- Methods and Main Features. The software SimaPro 5.0, developed by Dutch PRé Consultants, has been used as the analysis tool, because it is a well known, internationally accepted and validated tool. Different evaluation methods have been applied in the LCA evaluation: CML 2 baseline 2000, Eco-Points 97 and Eco-Indicator 99. Data used in the inventory analysis of this Part 1 come from: a) existing plants in operation; b) data bases implemented in the SimaPro 5.0 software -BUWAL 250, ETH-ESU 96, IDEMAT 2001. Different scenarios have been analyzed in both parts in order to estimate, not only the potential of reduction of the provoked environmental loads with the present state of the art of technology, but also the most likely future trend of technological evolution. In Part 1, different energy production models and the integration of desalination with other productive processes are studied, while the effect of the most likely technological evolution in the midterm, and the estimation of the environmental loads to the water transfer during drought periods are considered in Part 2. Results and Discussion The main contribution to the global environmental impact of desalination technologies comes from the operation, while the other phases, construction and disposal, are almost negligible when compared to it. Energy is very important in desalination, for this reason the environmental loads change a lot depending on the technology used for providing the energy used in the desalination process. Among the different analyzed technologies, RO is the least aggressive desalination technology (one order of magnitude lower than the thermal processes, MSF and MED) for the environment. When integrating thermal desalination with other productive processes taking advantage of the residual heat, the environmental loads of thermal desalination technologies is highly reduced, obtaining similar loads to that of RO. The environmental loads of desalination technologies are significantly reduced when an energy model based on renewable energies is used. Taking into account the technological evolution, which is experiencing the RO, a reduction of its environmental load by about 40% is to be expected in the mid-term. Conclusion The main conclusion of Part 1 is that, with the present state of the art of the technology, RO is clearly the desalination technology with a reduced environmental load (one order of magnitude lower than the thermal processes, MSF and MED). In the case of thermal desalination technologies, their environmental load can be highly reduced (about 1,000 times less) when integrated with other industrial processes. In the case of RO, the scores and the airborne emissions obtained from an electricity production model based on renewable energies are about 65-70 times lower than those obtained when the electricity production model is mainly based on fossil fuels. Recommendations and Outlook Although desalination technologies are energy intensive and provoke an important environmental load, they present a high potential in being reduced since: a) in the mid-term, it is to be expected that the different technologies could improve their efficiency significantly, b) the environmental loads would be highly reduced if the energy production models were not mainly based on fossil fuels and c) the energy consumption, particularly in the case of thermal desalination, can be drastically reduced when integrating desalination with other productive processes. The results presented in this paper indicate that a very interesting and promising field of research is available in order to reduce the environmental load of these vigorous and increasing desalination technologies. 相似文献
6.
Avasthi TS Kumar N Baddam R Hussain A Nandanwar N Jadhav S Ahmed N 《Journal of bacteriology》2011,193(16):4272-4273
Uropathogenic Escherichia coli (UPEC) causes serious infections in people at risk and has a significant environmental prevalence due to contamination by human and animal excreta. In developing countries, UPEC assumes importance in certain dwellings because of poor community/personal hygiene and exposure to contaminated water or soil. We report the complete genome sequence of E. coli strain NA114 from India, a UPEC strain with a multidrug resistance phenotype and the capacity to produce extended-spectrum beta-lactamase. The genome sequence and comparative genomics emanating from it will be significant in under-standing the genetic makeup of diverse UPEC strains and in boosting the development of new diagnostics/vaccines. 相似文献
7.
Hamer G 《Biotechnology advances》2003,22(1-2):71-79
The safety and acceptability of many widely used solid waste management practices are of serious concern from the public health point of view. Such concern stems from both distrust of policies and solutions proposed by all tiers of government for the management of solid waste and a perception that many solid waste management facilities use poor operating procedures. Waste management practice that currently encompasses disposal, treatment, reduction, recycling, segregation and modification has developed over the past 150 years. Before that and in numerous more recent situations, all wastes produced were handled by their producers using simple disposal methods, including terrestrial dumping, dumping into both fresh and marine waters and uncontrolled burning. In spite of ever-increasing industrialisation and urbanisation, the dumping of solid waste, particularly in landfills, remains a prominent means of disposal and implied treatment. Major developments have occurred with respect to landfill technology and in the legislative control of the categories of wastes that can be subject to disposal by landfilling. Even so, many landfills remain primitive in their operation. Alternative treatment technologies for solid waste management include incineration with heat recovery and waste gas cleaning and accelerated composting, but both of these technologies are subject to criticism either by environmentalists on the grounds of possible hazardous emissions, failure to eliminate pathogenic agents or failure to immobilise heavy metals, or by landfill operators and contractors on the basis of waste management economics, while key questions concerning the effects of the various practices on public health and environmental safety remain unanswered. The probable and relative effects on both public health and environmental safety of tradition and modern landfill technologies will be evaluated with respect to proposed alternative treatment technologies. 相似文献
8.
The problem of water use in industrial sectors is analyzed in the context of sustainability, and the manufacturing process as one of the most important water consumers is scrutinized. Some practices of water conservation and reduction of water consumption, as well as the implementation of advanced treatment processes for wastewater recycling are considered under the general aspect of process integration and control in order to minimize environmental discharges. Reduction of effluents in papermaking processes are discussed as well as preventative approaches. It is emphasized that four groups of methods can be applied in order to minimize water consumption: process changes, water reuse, regeneration reuse and regeneration recycling. Minimizing the water consumption and thus reducing the hydraulic load may help to improve effluent treatment, reduce operating costs and, when subsequent disposal is to sewers, minimize effluent disposal charges. The data presented show that initially producing less effluents will reduce the demands on the effluent treatment plant and thus save both money and efforts. Separation techniques for minimizing effluents and effluent loads are presented, as well as potential practices to ensure a sustainable use of water, grouped as short term and long term measures. Prevention measures for water consumption in a Romanian paper mill are considered and discussed in relation with best available techniques (BAT), taking into account both economical and environmental benefits. 相似文献
9.
Advances in poultry litter disposal technology--a review 总被引:7,自引:0,他引:7
Kelleher BP Leahy JJ Henihan AM O'Dwyer TF Sutton D Leahy MJ 《Bioresource technology》2002,83(1):27-36
The land disposal of waste from the poultry industry and subsequent environmental implications has stimulated interest into cleaner and more useful disposal options. The review presented here details advances in the three main alternative disposal routes for poultry litter, specifically in the last decade. Results of experimental investigations into the optimisation of composting, anaerobic digestion and direct combustion are summarised. These technologies open up increased opportunities to market the energy and nutrients in poultry litter to agricultural and non-agricultural uses. Common problems experienced by the current technologies are the existence and fate of nitrogen as ammonia, pH and temperature levels, moisture content and the economics of alternative disposal methods. Further advancement of these technologies is currently receiving increased interest, both academically and commercially. However, significant financial incentives are required to attract the agricultural industry. 相似文献
10.
Holly Ann Williams Joanna Gaines Molly Patrick David Berendes David Fitter Thomas Handzel 《PloS one》2015,10(11)
The international response to Haiti’s ongoing cholera outbreak has been multifaceted, including health education efforts by community health workers and the distribution of free water treatment products. Artibonite Department was the first region affected by the outbreak. Numerous organizations have been involved in cholera response efforts in Haiti with many focusing on efforts to improve water, sanitation, and hygiene (WASH). Multiple types of water treatment products have been distributed, creating the potential for confusion over correct dosage and water treatment methods. We utilized qualitative methods in Artibonite to determine the population’s response to WASH messages, use and acceptability of water treatment products, and water treatment and sanitation knowledge, attitudes and practices at the household level. We conducted eighteen focus group discussions (FGDs): 17 FGDs were held with community members (nine among females, eight among males); one FGD was held with community health workers. Health messages related to WASH were well-retained, with reported improvements in hand-washing. Community health workers were identified as valued sources of health information. Most participants noted a paucity of water-treatment products. Sanitation, specifically the construction of latrines, was the most commonly identified need. Lack of funds was the primary reason given for not constructing a latrine. The construction and maintenance of potable water and sanitation services is needed to ensure a sustainable change. 相似文献
11.
Land disposal of poultry litter is an environmental concern often associated to excess phosphorus (P) in soils and potential water pollution in regions with intense poultry production. Although poultry litter can be moved off the farm and traded as fertilizer, its transportation becomes less economical with increasing distances from the farm. Thus, new litter management alternatives are needed to reduce the environmental impact of P litter application to land. This paper summarizes established and emerging alternative technologies in the U.S. that facilitate handling, concentration, and transporting of litter P. Furthermore, it examines the potential integration of technologies into poultry litter management systems that could reduce poultry litter volume and increase P content in litter byproducts. The adoption of alternative technologies may encourage new opportunities to produce bio-energy, fertilizer, and other valuable P byproducts from poultry litter while reducing environmental impact and promoting sustainable poultry production. 相似文献
12.
《African Journal of Aquatic Science》2013,38(3):269-276
The construction of Pongolapoort Dam in 1973 on the Phongolo River in KwaZulu-Natal, South Africa, has considerably altered the hydrological behaviour and ecological response of the downstream floodplain. Changes in the flooding regime have had implications for the socio-economic importance of the floodplain and for the structure and functioning of its associated wetlands. Previous studies have recommended annual releases of water from the dam to sustain floodplain ecosystem goods and services. The current artificial water releases are limited by the size of the dam's sluices and by the demand for water from the local community. Therefore, water releases do not always follow the original natural flooding regime. To date, the influence of the changed hydrology on the ecology of the Phongolo floodplain system remains poorly known. As a basis for future integrated interdisciplinary research we synthesised the ecological and hydrological work conducted to date on the Phongolo floodplain. We suggest hydro-ecology as an important research direction needed to set environmental flows for the sustainable utilisation and management of the floodplain. Understanding the hydrological behaviour and ecological response of the Phongolo floodplain could help in the implementation of environmental flows by managers at the Department of Water and Sanitation and other stakeholders such as Ezemvelo KZN Wildlife. 相似文献
13.
《Ecological Indicators》2008,8(5):476-484
This paper proposes a water quality index (WQI) to subsidize management actions in the Médio Paranapanema Watershed in São Paulo State, Brazil, as a simple pollution indicator for aquaculture activity. Water quality of the Macuco and Queixada rivers was investigated for 2 years (from May 2003 to May 2005). The index proposed in this work is composed of three measurable environmental parameters—turbidity, total phosphorus and dissolved oxygen. Concentrations of these three variables were normalized on a scale from 0 to 100 and translated into statements of water quality (excellent, good, regular, fair and poor). The index was applied to seventeen monitoring points in the aquatic bodies described above and compared to others, one being that used by the Environmental Protection Agency of United States and proposed for the National Sanitation Foundation, other employing minimal index and the last one considering the minimum operator concept. The results show that the degradation in this watershed from aquaculture activity can be easily inferred with this index, which is more restricted than the others routinely used to infer water quality. 相似文献
14.
Montse Meneses Jorgelina C. Pasqualino Raquel Céspedes‐Sánchez Francesc Castells 《Journal of Industrial Ecology》2010,14(3):512-527
One of the most important problems today is the scarcity of fresh water safe enough for human, industrial, and agricultural use. Desalination is an alternative source of fresh water supply in areas with severe problems of water availability. Desalination plants generate a huge amount of brine as the main residual from the plant (about 55% of collected seawater). Because of that, it is important to determine the best environmental option for the brine disposal. This article makes a global environmental analysis, under Spanish conditions, of a desalination plant and an environmental assessment of different final brine disposals, representing a range of the most common alternatives: direct disposal, wastewater treatment plant (WWTP) outflow dilution, and dilution with seawater. The environmental profile of the plant operation and a comparison of the brine final disposal alternatives were established by means of the life cycle assessment (LCA) methodology. From an analysis of the whole plant we observed that the highest environmental impact was caused by energy consumption, especially at the reverse osmosis stage, while the most relevant waste was brine. From an analysis of brine final disposal we have elaborated a comparison of the advantages and detriments of the three alternatives. As all of them might be suitable in different specific situations, the results might be useful in decisions about final brine disposal. 相似文献
15.
中国餐厨垃圾处理的现状、问题和对策 总被引:22,自引:0,他引:22
餐厨垃圾具有高水分、高盐分、高有机质含量、组分时空差异明显、危害性与资源性并存的特点。目前国内外常用的餐厨垃圾处理技术如焚烧、卫生填埋、生态饲料、厌氧消化、好氧堆肥和蚯蚓堆肥等,通常存在着资源化利用效率低、经济效益不够理想的缺陷。总结相关文献及报道,中国在餐厨垃圾资源化处理上存在"行政瓶颈"和"技术瓶颈"两大方面的问题:"行政瓶颈"的解决之道在于完善管理及处理体系,各级政府部门切实重视、加大投入,强力推进垃圾分类投放;而对于"技术瓶颈",除综合运用多种现有处理技术外,开发新技术提高餐厨垃圾的资源化循环利用程度,是关键所在。 相似文献
16.
Intensive livestock production is connected with a number of environmental effects, including discharges to soils and surface waters and emissions to the atmosphere. In areas with a high livestock density the low availability of nearby arable land, together with the preferred use of chemical fertilizer by arable farmers, results in high off-farm disposal costs for manure. Furthermore, ammonia abatement technologies, such as treatment of exhaust air, are important as ammonia emissions may account up to a quarter of the total nitrogen flux. 相似文献
17.
“人体电磁兼容系统与电磁场处理水”一文分为三篇文章写 ,第一篇“I.人体电磁兼容系统” ,已在《生物磁学》发表 ,本文是第二篇。水占人体总重量的 70 %左右 ,因而在很大程度上人体的性能是由水的特性所决定。而我们研究电磁水之目的是为了人体的自然保健 ,因而本文专题讨论水。首先简介人们还不太注意的“水的异乎寻常的特性” ,尔后讨论“电磁场对水的作用” ,最后阐述“电磁水的特性” ,尤其是“水感应电磁场”这一特性。有关水的问题广泛而且复杂 ,动态性强 ,太多数水的现象的研究应该服从于“统计学规律” ,引入“量子力学”的处理方法是必要的 ,也简捷些。 相似文献
18.
19.
Ryu H Lu J Vogel J Elk M Chávez-Ramírez F Ashbolt N Santo Domingo J 《Applied and environmental microbiology》2012,78(12):4338-4345
While the microbial water quality in the Platte River is seasonally impacted by excreta from migrating cranes, there are no methods available to study crane fecal contamination. Here we characterized microbial populations in crane feces using phylogenetic analysis of 16S rRNA gene fecal clone libraries. Using these sequences, a novel crane quantitative PCR (Crane1) assay was developed, and its applicability as a microbial source tracking (MST) assay was evaluated by determining its host specificity and detection ability in environmental waters. Bacteria from crane excreta were dominated by bacilli and proteobacteria, with a notable paucity of sequences homologous to Bacteroidetes and Clostridia. The Crane1 marker targeted a dominant clade of unclassified Lactobacillales sequences closely related to Catellicoccus marimammalium. The host distribution of the Crane1 marker was relatively high, being positive for 69% (66/96) of the crane excreta samples tested. The assay also showed high host specificity, with 95% of the nontarget fecal samples (i.e., n = 553; 20 different free-range hosts) being negative. Of the presumed crane-impacted water samples (n = 16), 88% were positive for the Crane1 assay, whereas none of the water samples not impacted by cranes were positive (n = 165). Bayesian statistical models of the Crane1 MST marker demonstrated high confidence in detecting true-positive signals and a low probability of false-negative signals from environmental water samples. Altogether, these data suggest that the newly developed marker could be used in environmental monitoring studies to study crane fecal pollution dynamics. 相似文献
20.
V E Niemela 《Canadian journal of physiology and pharmacology》1984,62(8):968-970
This paper describes the extent of the hazardous and toxic chemical waste problems in Canada and discusses the management, treatment, and disposal methods commonly used in North America and Europe. The treatment and disposal techniques covered are biological, physical-chemical, incineration technologies, and secure land disposal. Some of the available and emerging technologies for destruction of polychlorinated biphenyls are also described. 相似文献