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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Diretrizes para o gerenciamento da água pluvial nas edificações escolares municipais da cidade de Ribeirão Preto. / Guidelines on rainwater management for Ribeirão Preto municipal school buildings.

Hernandes, André Teixeira 31 August 2006 (has links)
Made available in DSpace on 2016-06-02T20:09:05Z (GMT). No. of bitstreams: 1 DissATH.pdf: 18368287 bytes, checksum: b45251643897100029d341df26cf3598 (MD5) Previous issue date: 2006-08-31 / The current projects of rainwater plumbing systems are extremely simple and present only one exclusive concern: to divert the rainfall from the place where it occurs to the drainage public system. In general, it s possible to verify that they do not attend even the word semantic meaning. The no existence of a coordinated set of action aiming at ampler results makes rainwater plumbing system unconcerned with the surrounding area, not composing harmonically with the urban site in particular, and the environment as a general form. Generally, designers expect only rainwater goes toward out of the site, and that is a good result of a good system. Due the lack of attention to the impact that generates and does harm to society, they ignore its potential as instrument of water building conservation. They do not assess correctly its capacity as a source of supply of so expensive and scarce water, according with its necessities, conveniences or limitations that can exist. Therefore, the goal of this study is to propose a new function for the rainwater plumbing system, in special for Ribeirão Preto municipal school buildings, becoming it from a passive to an active system of environment protection. With a proper and molded conception for this new proposal, the system must contemplate the aspects related to the reduction of the impacts caused by the civil construction activities on urban sites, its preservation and providing environment education for people and also, as an worthy water building management tool. / Os atuais projetos dos sistemas prediais de água pluvial são em sua grande maioria, extremamente simples, apresentando uma única e exclusiva preocupação: a transferência da precipitação do local onde ocorre para o sistema público de drenagem, constituído por sarjetas, galerias e por fim, os córregos e rios. Verifica-se que, em geral, não atendem nem ao sentido semântico da palavra sistema. A inexistência de um conjunto coordenado de ações visando um resultado mais amplo faz com que o sistema predial de água pluvial se dissocie de seu entorno, sem se compor harmônicamente com o meio urbano em particular, e o meio natural de uma forma geral. Na concepção atual de seus projetistas, o simples encaminhamento destas águas para fora da edificação é o resultado esperado de um bom sistema. Alheios ao impacto que gera e que penaliza a socidade, passam ao largo de seu potencial como instrumento de conservação de água nas edificações. Ignoram sua capacidade de suprir as mesmas com tão caro e cada vez mais escasso recurso, de acordo com as necessidades, conveniências ou limitações que possam existir. Portanto, o objetivo deste trabalho consiste na proposição de uma nova função para o sistema predial de água pluvial, em especial nas escolas muncipais de Ribeirão Preto, transformando-o de um sistema passivo de captação e drenagem em um sistema ativo de conservação ambiental. Com uma concepção própria e moldada para esta nova proposta, o sistema deve contemplar os aspectos relacionados à redução dos impactos causados pela ocupação do solo no meio urbano, à preservação e educação ambiental e também, à gestão da oferta de água nas edificações.
82

Aproveitamento de água pluvial em edifícios residenciais multifamiliares na cidade de São Carlos. / Rainwater harvesting in a residential tall building in the city of São Carlos.

Campos, Marcus André Siqueira 06 May 2004 (has links)
Made available in DSpace on 2016-06-02T20:09:10Z (GMT). No. of bitstreams: 1 DissMASC.pdf: 3170204 bytes, checksum: 83bd0768232793a648b29a0d4da7f753 (MD5) Previous issue date: 2004-05-06 / Financiadora de Estudos e Projetos / The potable water scarcity afflicts the begging of the 21st Century, being today, one of the main worries of the manhood. This way, it becomes necessary to reduce the per capita consumption. From the actions that promote the racional use of water, the technological ones seems to be , in the most of the cases, the most recomended to reduce the consumption without being necessary radical changes of the users. One of these technologies is the rainwater harvesting. This one erges as an action of good perspectives since it subistitutes the use of potable water in activities where it is not necessary a good quality water, younder, it will reduce the amount of stormwater in the public drainage net, working as a non-structural action of urban drainage. The lack of kwondlege as well a the real advantages that a rainwater system can bring to a builind, is the points to find out about this issue.. At this paper, it seeked to clear this techonolgy up with the study of national and international examples . It also seeked the cistern sizing, getting the best results to technical and economical issues, as well, as procedures to design and to mantain the devices that make part of the system used in this study. Besides that, it studied the changes that would be necessary to build the system, and the possibles changes at the work routine of the construction company. It also studied the financial feasibility of the investiment of this interprisement, checking the real economical advantages that can be get. It is waited that this research contributes to the development of this techonology, contributing to Racional use of water in residential tall buildings. / A escassez de água potável atormenta o início do Século XXI, sendo hoje uma das principais preocupações da humanidade neste século que começa. Dessa forma, surge a necessidade de redução do consumo per capita. Dentre as ações que promovem o uso racional da água, as tecnológicas parecem ser , na maioria dos casos, as mais recomendadas para reduzir o consumo sem que seja necessário mudanças radicais nos hábitos dos usuários. Entre estas, o aproveitamento de água pluvial surge como uma ação de boas perspectivas, pois substitui o uso de água potável onde a qualidade desta não é necessária e, a retirada desta diminuirá a quantidade de volume de água pluvial lançada na rede pública de drenagem, funcionando como uma medida não-estrutural de drenagem urbana. A falta de conhecimento técnico bem como das reais vantagens que um sistema de aproveitamento de água pluvial poderá trazer para uma edificação são as principais incógnitas desse assunto. Neste trabalho buscou-se clarear a tecnologia, com o estudo de diversos casos nacionais e internacionais. Também se buscou realizar o dimensionamento de forma mais correta e econômica, bem como listar procedimentos para elaboração e manutenção de todos os elementos constituintes do sistema utilizado no edifício objeto de estudo. Além disto, verificou-se as possíveis interferências nos processos construtivos, além de alterações das rotinas de trabalho da construtora, além do estudo da viabilidade financeira do empreendimento, verificando as reais vantagens da implantação do sistema neste caso. Espera-se que esse trabalho contribua para o desenvolvimento de uma tecnologia específica para o uso racional de água.
83

Regnvatten från hustak som resurs : Användning av takavrinningsvatten som resurs och kvalitetskriterier

Ask, Paulin January 2017 (has links)
Flooding from rainwater in megacities around the world is a major problem which is growing even bigger with the scenarios that has been predicted by IPCC. The problem has to be taken care of somehow and one possible solution could be to use the water once it just hit the ground area. This study will show some of the opportunities we have to use runoff water from roofs with local solutions in Gothenburg and analyse quality differences of run off-water with raw water from the river Göta Älv, which today is used as drinking water in Gothenburg. Among some of the existing solutions for rainwater today, for example stone filter and trees, the result will show specifically one solution which is used at Stadsbyggnadskontoret in Gothenburg city center. The results of the run off-water show higher values of metals, nitrogen and phosphorus than Göta Älv and comparison between run off from green roof and run off from other roof materials shows lower values of the same chemical parameters. Since the values are taken from a report which contains schablon values, the results are just symbolic. A hypothetical calculation which shows that one year of estimated volume rainwater on a building example could provide for either 31 people/year total consumption or 100 people/year only for laundry and flushing toilets.
84

Hospodaření s dešťovou vodou v městských sídlech / Storm water management in urban areas.

Vaculík, Tomáš January 2019 (has links)
The diploma thesis is focused on Storm water management in urban areas. The first task for processing thesis was to arrange meeting with MČ Brno - Bohunice Ing. Antonín Crha, who has provided necessary information about the targeted location the and the reservoir for accumulation of rainwater collected. The practical part of the thesis is to capture the rainwater drainage in the existing rainwater sewerage system using the newly built pumping station and then pumping into the existing, unused reservoir. Accumulated water in the reservoir is planned to be used for the needs of the city, gardeners and other customers. The first part of the diploma thesis describes the management of refined water in the Czech Republic, Denmark and Germany. The first part also provides description of measures and technologies for the management of rainwater. Finally, there is description of the pumping station and borehole objects and the program for calculating the rainfall from the urbanized area. In the practical part of the diploma thesis the selected variants are described, rewarded and evaluated. The diploma thesis deals with two variants, that are guided along the same route, with the difference of the construction of the drilled well in the second variant. Both variants are handled by pumping. The option of the gravity inflow was rejected because of the large countersink of rainwater sewerage.
85

Modelling of Inflow and Infiltration into Wastewater Systems with Regression and Random Forest / Modellering av Inflöde och Infiltration i Avloppssystem med Regression och Random Forest

Steen Danielsson, Viggo January 2022 (has links)
The aim of this thesis was to evaluate the validity of statistical modelling, with regards to flow in wastewater systems based on precipitation. A wastewater system, which is a system of pump-stations connected via pipes, is affected by precipitation as rainwater enters the system. The rainwater that enters the system can sometimes, especially if the precipitation is heavy, increase the flow by several hundred percent. The goal with the models created for this report was, to first predict how much rainwater there was in the wastewater system based on precipitation, and second, to examine where in a geographical grid this rainwater entered the system. For the first goal a linear regression model was applied, this model showed that it was indeed possible to predict excess water in the system, but large errors for individual time points where to be expected, especially for light precipitation. For the second goal a random forest model was applied. This model however gave no additional insight beyond what an initial correlation study between precipitation in different parts of the geographical grid and flow had already shown. The areas in the geographical grid pointed out by both the random forest model and the initial correlation study were not the actual uptake areas of the pump-station these models were applied to. This leads to the conclusion that for the data set used, and with the models applied in the manner in which they were in this thesis, it was not possible to predict where rainwater enters the system. / Målet med den här rapporten var att undersöka möjligheten att modellera regnvattens påverkan på vattenflödet i avloppsystem, med statistiska modeller. Ett avloppsystem är i dess enklaste form ett nätverk av pumpstationer sammanbunda med rör. Det här systemen påverkas av nederbörd då oönskat regnvatten kommer in via stuprör, avloppsbrunnar och sprickor i rören. Regnvattnet kan i vissa fall, särskilt under perioder med mycket nederbörd, öka flödet i avloppsystemet med flera hundra procent. Modellerna tillverkade för den här rapporten undersökte två olika aspekter av regnvattnets påverkan: Kan flöde i avloppssystemet modelleras med regnvatten? Och kan modellerna avgöra var regnvatten kommer in i avloppsystemet? Den första frågan undersöktes med linjär regressionsanalys, modellerna tillverkade med regression visade att det gick att modellera flöde i avloppsystemet med regnvatten, det bör dock nämnas att stora fel i enskilda tidssteg var att förvänta, speciellt för modellering då nederbörden är låg. Den andra frågan utvärderades med en ”random forest” modell. Den här modellen gav ingen ytterligare information angående var regnvatten kommer in i systemet, utöver vad som redan hade visats av en korrelationsstudie gjord i början av projektet. Både korrelationsstudien och ”random forest” modellen visade också på att regnvattnet kom från platser som inte var sammankopplade med den pumpstation testerna gjordes på. På grund av detta drogs slutsatsen att det inte gick att ta reda på var regnvattnet kommer in i systemet, med den data som använts, och på det sätt som modellerna har använts i den här rapporten.
86

Life Cycle Assessment of Rainwater Harvesting Systems at Building and Neighborhood Scales and for Various Climatic Regions of the U.S.

Devkota, Jay P. January 2015 (has links)
No description available.
87

A multi-criteria decision analysis framework for sustainable rainwater harvesting in Ibadan, Nigeria

Lade, Omolara January 2014 (has links)
The approach to water management worldwide is currently in transition, with a shift from centralised infrastructures to greater consideration of decentralised technologies, such as rainwater harvesting (RWH). Initiated by recognition of drivers, including water demand, increasing risk of ground-water pollution and flooding, the value of RWH is filtering across the academic-policy boundary. However, in Nigeria, implementation of sustainable water management (SWM), such as RWH systems, is inefficient social, environmental and technical barriers, concerns and knowledge gaps exist, which currently restrict its widespread utilisation. This inefficiency contributes to water scarcity, water-borne diseases, and loss of lives and property due to flooding. Meanwhile, several RWH technologies have been developed to improve SWM through both demand and storm-water management. Such technologies involve the use of storage tanks, surface water reservoirs and ground-water recharge pits as storage systems. A framework was developed to assess the significance and extent of water management problems, match the problems with existing RWH-based solutions and develop a robust ready-to-use multi-criteria analysis tool that can quantify the costs and benefits of implementing several RWH-based storage systems. The methodology adopted was the mixed method approach, involving a detailed literature review, followed by a questionnaire survey of 1067 household respondents, 135 Nigerian Architects and Civil Engineers and focus group discussion with Stakeholders. A total of 1042 sets of data were collected through a questionnaire survey and analysed using SPSS, Excel and selected statistical methods to derive weightings of the attributes for the tool. Following this, three case studies were selected to collect data for hydrological modelling using the RainCycle model. From the results it is found that the most important barrier constraining sustainable RWH regime in Ibadan was obsolete and insufficient operational equipment, followed by poor renumeration of water corporation staff and misuse of available funds. In addition, the measure of importance of storage capacity was established, with the highest score of 4.5 which reflects the general inadequacy of storage as a major barrier to the adoption of RWH as a sustainable water management method. Further, respondents’ major health hazards associated with drinking contaminated water was established. A larger proportion (61.2%) of respondents chose prevalence of typhoid fever; some have a prevalence of diarrhea (19.4%), while few of respondents’ water sources is free from water-borne diseases (2.3%). The tool developed is an integrated platform of related evaluation techniques, including Whole Life Cycle Cost Analysis and Multi-Attribute Utility Theory. The tool uses data including cost and quantities of materials for building a RWH storage system and quantifies the cost and benefits of alternative RWH-based systems that can improve project management. This tool is novel, given its integration of the analytical techniques mentioned above and application for selecting the most appropriate RWH-based SWM systems. The implementation of the tool is envisaged to provide an objective platform for the quantification of the costs and benefits of RWH-based systems prior to implementation.
88

A Feasibility Analysis of Site-Level Stormwater Reuse for Commercial Developments in Canada

Nanos, Michael 19 August 2013 (has links)
Municipalities are experiencing a growing water management challenge as a result of population growth in water-dependent communities. The rising cost of potable water, in addition to limits placed on stormwater discharges, provide opportunities for the wide-scale implementation of stormwater reuse. This thesis presents a feasibility analysis of a novel site-level stormwater reuse concept for commercial developments in Canada. Historical rainfall data and SWMM 5.0 were used to evaluate the hydrologic potential of the reuse system to replace potable water for end-use demands of toilet flushing and garden irrigation on single- and multi-tenant commercial sites. Performance criteria were used to evaluate: (i) the volume and percent potable water replaced with reclaimed stormwater, (ii) the volume and frequency of potable water ‘top-ups’ to the reclaimed stormwater storage facility, and (iii) the volume and frequency of overflows in the reclaimed stormwater storage facility. A discounted payback method was used to determine the length of time (in years) required for annual water savings to equal the initial capital investment of the stormwater reuse system. The analysis was performed from the perspective of the private landowner in six Canadian locations, including Vancouver, Edmonton, Regina, Saskatoon, Toronto, and Quebec City. The methodology and results presented is intended to provide insight to landowners and municipal bodies on the potential of site-level stormwater reuse to aid large-scale adaption and implementation. The results suggest that regions with high average annual rainfall depths produce high potable water replacement rates ranging from 64% to 99% while cities that experience seasonal arid conditions and lower average annual rainfall depths achieve lower potable water replacement rates in the range of 30% and 83%. The test locations of Vancouver and Quebec achieved longer payback periods of 10 years to 26 years due to the relative low cost of potable water. The Saskatoon and Regina locations produced shorter payback periods ranging from 3 to 6 years due to the higher potable water prices. Toronto was found to have relatively short payback periods ranging from 4 to 5 years on account of its high potable water replacement rates and high potable water prices. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-08-19 14:44:23.024
89

Rainwater harvesting in the UK : a strategic framework to enable transition from novel to mainstream

Ward, Sarah January 2010 (has links)
The approach to water management worldwide is currently in transition, with a shift evident from purely centralised infrastructure to greater consideration of decentralised technologies, such as rainwater harvesting (RWH). Initiated by recognition of drivers including increasing water demand and increasing risk of flooding, the value of RWH is beginning to filter across the academic-policy boundary. However, in the UK, implementation of RWH systems is not straight forward; social and technical barriers, concerns and knowledge gaps exist, which currently restrict its widespread utilisation. Previously, these issues have been examined independently. The research described in this thesis highlights the need for interdisciplinary working to lower the barriers and resolve the concerns. Consequently, a combination of social and engineering research perspectives, methods and analysis is utilised to achieve the aim of the research: the production of a strategic framework to support the implementation of RWH in the UK. The framework is the culmination of empirically derived social and technical evidence bases including: surveys with householders and architects; interviews with small to medium enterprises (SMEs); a design and performance evaluation of a non-domestic RWH system; non-domestic water closet (WC) monitoring to develop a demand profile and a water quality study and health impact assessment (HIA) of a non-domestic RWH system. Results indicate that householders were willing but not able to implement RWH, due to financial constraints and perceived maintenance burdens. For SMEs 5 ‘implementation deficit categories’ were identified, which undermined their ability to implement. The use of continuous simulation tools, with appropriate data, need to be promoted and the non-domestic demand profile derived was distinctly different to the well-established domestic profile, yielding implications for system design. The non-domestic RWH system was able to achieve an average water saving efficiency of 97% for the period monitored and the HIA quantified the risk to health as being within the recognised screening level. Triangulation of the results into an integrated socio-technical evidence base facilitated the identification of three core strategy aims, their corresponding actions and actors (stakeholder groups). The overall strategic framework is presented in the form of a Venn diagram. It is unlikely the comprehensive nature of the strategic framework would have been achieved, if the interdisciplinary process had not been undertaken. Therefore adoption of a socio-technical approach to implementation is vital, if RWH in the UK is to transition from novel to mainstream.
90

Identification des sources d’alkylphénols et de phtalates en milieu urbain : comparaison des rejets à dominante urbaine (domestique) par rapport à des rejets purement industriels / Identification of the sources of alkylphénols and phtalates in urban zones : comparison of the discharges to urban dominant (domestic and home-made) with regard to purely industrial discharges

Bergé, Alexandre 16 November 2012 (has links)
Les phtalates et les alkylphénols sont des composés organiques générés par l'industrie chimique, qui entrent dans la composition des matières plastiques, pour les phtalates, et des détergents, pour les alkylphénols. Leurs productions mondiales avoisinent les 6 millions de tonnes pour les phtalates et 500 000 tonnes pour les alkylphénols. Ces composés sont considérés comme ubiquitaires dans l'environnement, c'est-à-dire qu'ils sont retrouvés dans tous les compartiments environnementaux (de l'atmosphère au milieu naturel). Par ailleurs, ils sont considérés comme des perturbateurs endocriniens et peuvent donc causer des dommages aux faunes et flores présentes dans le milieu naturel. Ce travail de thèse a permis de déterminer les niveaux de contamination des eaux usées en phtalates et alkylphénols dans plusieurs compartiments environnementaux situés en zone urbaine. Ainsi, des prélèvements effectués, par temps sec, ont permis de déterminer la qualité des eaux brutes vis-à-vis des paramètres globaux, des phtalates et des alkylphénols dans les rejets industriels, domestiques, les émissaires parisiens ainsi que dans les eaux usées transitant au sein d'une station d'épuration majeure d'Ile-de-France (Seine Centre, Colombes, 92). Ces résultats reflètent certaines spécificités et disparités du réseau d'assainissement, notamment marqués par la forte variabilité qui entoure, à la fois, le prélèvement et les niveaux de contamination par ces micropolluants. Au niveau des rejets industriels, de forts contrastes ont été observés entre les différents secteurs répertoriés (traitement des textiles, traitement de surface, métallurgie, industries pharmaceutiques, etc.). Globalement, les résultats des flux par équivalent-habitant soulignent que les apports domestiques sont la première source de contamination pour ces polluants en région parisienne. En effet, la contribution des apports industriels est inférieure à 5 %, pour tous les composés, quelque soit le secteur industriel considéré. L'étude des émissaires parisiens a permis de montrer une certaine stabilité temporelle de la qualité des effluents dans la partie avale du réseau d'assainissement. En revanche, cette étude a également mis en exergue des divergences et des similitudes entre les sous-bassins versants drainés par les différents émissaires. Ainsi, une étude statistique a montré que les émissaires Saint Denis Achères et Clichy Achères Argenteuil apparaissent significativement plus contaminés que les émissaires Sèvres Achères Reuil et Clichy Achères Bezons. Au niveau de l'efficacité des ouvrages de traitement, les résultats obtenus pour la station d'épuration de Seine Centre ont confirmé son efficacité pour les paramètres globaux communément utilisés pour déterminer la qualité des eaux usées. D'autre part, les résultats obtenus sur l'abattement des phtalates et des alkylphénols (rendements supérieurs à 83 % pour tous les composés) soulignent que même si les stations d'épuration ne sont, initialement, pas construites pour réduire et/ou éliminer les micropolluants, elles y parviennent de façon significative. A l'échelle des ouvrages, le traitement primaire par décantation physico-chimique lamellaire a permis de mettre en évidence l'élimination des polluants hydrophobes tels que le DEHP, le NP, le DnBP et le BBP. Le traitement secondaire par biofiltration a mis en exergue son efficacité à abattre significativement tous les polluants, aussi bien les composés légers (DEP) que les autres composés / Phthalates and alkylphenols are organic molecules generated by the chemical industry, entering the composition of plastics, for phthalates, and detergents for alkylphenols. Their worldwide productions are around 6 million tons and 500,000 tons, respectively. It is now obvious from the concentrations and contents measured in the various environmental compartments that phthalates and alkylphenols are ubiquitous environmental contaminants. Indeed, they are found in all environmental compartments (from the atmosphere to the natural environment) at significant levels. These contaminants are also recognized as endocrine disrupting compounds and can cause damages to fauna and flora present in the natural environment. This work has identified levels of wastewater contamination of phthalates and alkylphenols in various environmental compartments in urban areas. Thus, samples taken, during dry weather periods, were used to determine the quality of raw water for global parameters, phthalates and alkylphenols within industrial and domestical discharges as well as the sewer network and a major Parisian sewage treatment plant (Seine Centre, Colombes, 92). These results reflect certain characteristics and disparities of the sewer network, including both high variability of the sampling and the contamination levels by these micropollutants. For industrial discharges, significant disparities have been observed between the different sectors listed (textile manufacturing, surface treatment, metallurgy, pharmaceutical industries, etc.). Overall, the results confirm that household inputs correspond to the first source of contamination in Parisian conurbation. Indeed, the contribution of industrial inputs is less than 5%, for all compounds, whatever the industrial sector. The study of the Parisian sewer network showed some temporal stability of wastewaters in the downstream part. This work however also highlighted disparities and similarities between the sub-watersheds drained by the sewer network. Thus, the northern part of the Parisian network (SDA and CAA) appears to be more contaminated than the Southern part (CAB and SAR).The results obtained for Seine Centre wastewater treatment plant (WWTP) confirms the effectiveness of the treatment processes on the removal on the routine water quality parameters. Additionally, the results on the elimination of phthalates and alkylphenols in sewage treatment plant (yields above 83% for all compounds) confirm that even if WWTP are initially not designed for reducing and/or eliminating micropollutants, they proceed significantly. During primary treatment, physicochemical lamellar clarification underlined the removal of hydrophobic pollutants such as DEHP, NP, DnBP and BBP. During the secondary treatment, biofiltration highlighted its effectiveness in eliminating all pollutants, as well as volatile compounds (DEP) and other contaminants

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