Rainwater Treatment for Domestic Use

The insufficiency of clean water for today usage has been very critical case. This is due to increasing of population, modern urbanization and also pollution that can cause water source affected by contaminants. So, in order to overcome this problem, the interest is much in the filtering of roof-collected rainwater. One of the techniques was to treat the rainwater by UV irradiation and carbon adsorption. This study was carried out to investigate the effectiveness of bacteria and another contamination removal from rainwater through ultraviolet irradiation and carbon adsorption. The parameter tested for rainwater was E-coli, coliform, turbidity and color. The rainwater was taken from tile roof at the student hostel, UTP. The experiment was conducted for 2, 4, 6, 8, 12 and 24 hours continuous circulation passing through with UV lamp. The results for rainwater before undergo treatment was 1 MPN for E-coli, coliform 7.3 MPN, turbidity 1.97 NTU, color 5NTU and pH 7.76. After 24 hours treatment, the results for the treated rainwater was 0 MPN for E-coli, 0MPN for coliform, turbidity 3.19NTU, color 7.7NTU and pH 6.5. The treated rainwater was safe for domestic usage according to National Standard for Drinking Water Quality. The acceptable value for drinking water for drinking water is 0MPN/100ml for E-coli, coliform 0MPN/100ml, turbidity 5NTU, color 15NTU and 6.5-8.5 for pH

Using Stormwater in a Sponge City as a New Wing of Urban Water Supply—A Case Study

Rapid and even disruptive innovations are needed to make cities fit for the future. The particular challenge will be to transform existing urban spaces in order to increase climate resilience. Along these lines, rainwater harvesting has taken place insufficiently to date, even when Sponge City concepts are implemented. Thus, the concept presented here addresses existing urban neighborhoods and proposes to collect rainwater from nearby rooftops and treat it in decentral treatment units called “City Water Hubs” (CWH) equipped with modular coupled low-energy technologies to produce various customized “City Water” qualities, and store it until it can be used or distributed. A feasibility study with a focus on the campus area at the main building of the Leibniz University of Hannover, the determined rainwater qualities, and the results from investigations with two laboratory test plants provided the basis for the technical design of the pursued concept. The feasibility study showed how sufficient rainwater for irrigation purposes can be made available for the listed large university park even under extreme dry and heat wave conditions. If large portions of the roof area (11,737 m2) of the university’s main building were activated, even in a dry year with only 49.8% of the average precipitation, only 19.8% of the harvested stormwater would be needed for irrigation. The rainwater samples showed TSS concentrations of up to 7.54 mg/L, COD of up to 58.5 mg/L, and NH4 of up to 2.21 mg/L, which was in line with data reported in the literature. The treatment technologies used for the two pilot plants are proven approaches for stormwater treatment and were composed as follows: (1) gravity-driven membrane filtration (GDM) and (2) slow sand filter with integrated activated carbon (AC) layer. The treatment with both (1) and (2) clearly improved the rainwater quality. The GDM reduced turbidity by 90.4% and the Sand/AC filter by 20.4%. With regard to COD, the studies for GDM did not show a clear elimination trend; the Sand/AC filter reduced the COD by 77%. Taken together, decentralized low-energy rainwater treatment can reliably provide quality-assured City Water for any specific use. Regarding the treatment design, GDM is preferable and can be better operated with downstream UV disinfection, which might be needed to reduce the pathogenic load, e.g., for local heat control measures. The research steps presented here will pioneer the development of a city-wide rainwater harvesting infrastructure on the way of establishing stormwater as a resource for a new wing of urban water supply. The presented findings will now result in the implementation of a full-scale CHW on the campus to ensure long-term irrigation of the listed park, relieving the public drinking water supply

Urban rainwater harvesting systems: Research, implementation and future perspectives.

Published onlineJournal ArticleReviewThis is the author accepted manuscript. The final version is available from IWA Publishing via the DOI in this record.While the practice of rainwater harvesting (RWH) can be traced back millennia, the degree of its modern implementation varies greatly across the world, often with systems that do not maximize potential benefits. With a global focus, the pertinent practical, theoretical and social aspects of RWH are reviewed in order to ascertain the state of the art. Avenues for future research are also identified. A major finding is that the degree of RWH systems implementation and the technology selection are strongly influenced by economic constraints and local regulations. Moreover, despite design protocols having been set up in many countries, recommendations are still often organized only with the objective of conserving water without considering other potential benefits associated with the multiple-purpose nature of RWH. It is suggested that future work on RWH addresses three priority challenges. Firstly, more empirical data on system operation is needed to allow improved modelling by taking into account multiple objectives of RWH systems. Secondly, maintenance aspects and how they may impact the quality of collected rainwater should be explored in the future as a way to increase confidence on rainwater use. Finally, research should be devoted to the understanding of how institutional and socio-political support can be best targeted to improve system efficacy and community acceptance

The Brookside Farm Wetland Ecosystem Treatment (WET) System: A Low-Energy Methodology for Sewage Purification, Biomass Production (Yield), Flood Resilience and Biodiversity Enhancement

Wastewater from domestic developments, farms and agro-industrial processing can be sources of pollution in the environment; current wastewater management methods are usually machine-based, and thus energy consuming. When Permaculture Principles are used in the creation of water purification and harvesting systems, there can be multiple environmental and economic benefits. In the context of energy descent, it may be considered desirable to treat wastewater using minimal energy. The constructed wetland design presented here is a low-entropy system in which wastewater is harvested and transformed into lush and productive wetland, eliminating the requirement for non-renewable energy in water purification, and also maximising benefits: biodiversity, flood resilience and yield. In permaculture design, the high concentrations of nitrogen and phosphorous compounds in sewage are viewed as valuable nutrients, resources to be harvested by a constructed wetland ecosystem and converted into useful yield. Similarly, rainwater runoff is not viewed as a problem which can cause flooding, but as a potential resource to be harvested to provide a yield. This paper presents a case study, with both water quality and productivity data, from Brookside Farm UK, where the use of Permaculture Design Principles has created a combined wastewater management and purification system, accepting all site water

Groundwater research and management: integrating science into management decisions. Proceedings of IWMI-ITP-NIH International Workshop on "Creating Synergy Between Groundwater Research and Management in South and Southeast Asia," Roorkee, India, 8-9 February 2005

Groundwater management / Governance / Groundwater development / Artificial recharge / Water quality / Aquifers / Groundwater irrigation / Water balance / Simulation models / Watershed management / Water harvesting / Decision making / South East Asia / Bangladesh / China / India / Nepal / Pakistan / Syria

오염물질 펄스 유입에 대비한 빗물 수집 시스템 설계 및 작동 개선

학위논문(석사) -- 서울대학교대학원 : 공과대학 건설환경공학부, 2021.8. 재니스.Rainwater harvesting (RWH) has attracted global attention as a solution for the urban water crisis; however, the water quality can be impacted by particulate matter and soluble contaminants. Therefore, the inlet and outlet configurations of the storage tank should be designed to minimize bottom sediment resuspension and prevent the transport of soluble contaminants. To overcome these issues pertaining to single tank systems, multiple tank systems with similar volumes have been implemented globally. However, limited research has been conducted to assess the effect of the number of tanks on harvested water quality under a sudden pollutant input. In addition, many researchers have investigated design and operational aspects of RWHs with respect to particulate matter removal, but not much research is available on how operations of RWHs affect the removal of soluble pollutants. Thus, this study investigated the effects of the inlet and outlet configurations of a rainwater storage tank on particle resuspension and residence time distribution for an instantaneous input of a conservative tracer. It was observed that J type inlets can reduce sediment resuspension by more than 50% while detaining and mixing a conservative pollutant, thus preventing the concentration from reaching the outlet as a plug flow. Although inlet height did not have a significant influence on the quality of water at the outlet, parameters such as inflow velocity and outlet height exerted a considerable influence on sludge resuspension and residence time distribution. The experiments also highlighted the importance of regulating the initial water level of the storage tank and regular flushing of bottom sediment to maintain the stored water quality. Next, the authors have investigated the effect of the number of tanks on particulate matter distribution in multi-tank systems and observed that more than 60% of the particle mass input was retained in the first tank. By increasing the number of tanks, the particle mass reaching the final tank becomes constant despite changes in the flowrate and influx particle mass. Furthermore, a soluble contaminant entering a multi-tank system was observed to reside within the system for a prolonged time by approximately a factor of two, which is favorable for developing a response strategy. It is recommended by the authors that at least three tanks should be used to gain the benefits of a multiple-tank RWH system. Finally, this research tried to quantify the amount of soluble contaminant influx (salt) that can be removed when the drain is operated, and the water overflowed. More than 20% of the pollutant influx was removed when the drain was operated at half capacity level in a single tank system. In a multi-tank RWH system, operation of the drain in the second tank was more effective than using the drain of the first tank. A significant amount of soluble pollutants can be removed with overflow, specially, in a single tank system. The results of this study can be used to suggest operational and automation recommendations.빗물 수집(RWH)은 도시 물 위기에 대한 해결책으로 세계적인 주목을 받고 있지만, 수질은 입자 물질과 수용성 오염물질에 의해 영향을 받을 수 있다. 따라서 저장 탱크의 입구 및 출구 구성은 바닥 침전물 재지연을 최소화하고 수용성 오염물질의 이동을 방지하도록 설계되어야 한다. 단일 탱크 시스템과 관련된 이러한 문제를 극복하기 위해 유사한 용량의 여러 탱크 시스템이 전세계적으로 구현되었다. 다만 갑작스러운 오염물질 유입에 따라 탱크 수가 수확된 수질에 미치는 영향을 평가하기 위한 연구는 제한적으로 이뤄졌다. 또한 많은 연구자들이 입자 물질 제거와 관련하여 RWH의 설계 및 작동 측면을 조사했지만, RWH의 작동이 수용성 오염물질 제거에 어떻게 영향을 미치는지에 대한 연구는 많지 않다. 따라서, 이 연구는 보수적인 추적자의 즉각적인 입력에 대한 빗물 저장 탱크의 입구 및 출구 구성이 입자 재서스펜션 및 거주 시간 분포에 미치는 영향을 조사하였다. J형 흡입구는 침전물 재서스펜션을 50% 이상 줄일 수 있는 동시에 보수적인 오염물질을 억제·혼합할 수 있어 플러그 흐름으로 농도가 배출구에 도달하는 것을 방지할 수 있는 것으로 관찰됐다. 입구 높이는 출구의 수질에 큰 영향을 미치지 않았지만, 유입 속도 및 출구 높이와 같은 매개변수는 sludge 재지연 및 거주 시간 분포에 상당한 영향을 미쳤다. 실험은 또한 저장 탱크의 초기 수위를 조절하고 저장된 수질을 유지하기 위해 바닥 침전물을 정기적으로 flushing하는 것이 중요하다는 것을 강조했다. 다음으로, 저자들은 다중 탱크 시스템의 입자 물질 분포에 대한 탱크 수의 영향을 조사했으며, 첫 번째 탱크에는 입자 질량 입력의 60% 이상이 유지된다는 것을 관찰했다. 탱크의 수를 증가시킴으로써, 유속과 유입 입자 질량의 변화에도 불구하고 최종 탱크에 도달하는 입자 질량은 일정해진다. 또한 다중 탱크 시스템에 유입되는 수용성 오염물질이 시스템 내에 약 2배 정도 오랫동안 존재하는 것으로 확인되었으며, 이는 대응 전략을 수립하는 데 유리한다. 저자들은 다중 탱크 RWH 시스템의 이점을 얻기 위해 최소한 세 개의 탱크를 사용해야 한다고 권고한다. 마지막으로, 본 연구는 배수구가 작동되고 물이 넘칠 때 제거할 수 있는 수용성 오염물질 유입량(소금)을 정량 화하려고 시도했다. 단일 탱크 시스템에서 배수구를 절반 용량으로 가동하면 오염물질 유입량의 20% 이상이 제거될 수 있었다. 다중 탱크 RWH 시스템에서는 두 번째 탱크의 배수구 작동이 첫 번째 탱크의 배수구보다 더 효과적이었다. 특히 단일 탱크 시스템에서 상당한 양의 수용성 오염 물질을 오버플로로 제거할 수 있다. 이 연구 결과를 사용하여 운영 및 자동화 권장 사항을 제안할 수 있다.Chapter 1. Introduction 1 1.1. Background 1 1.1.1. Rainwater Harvesting and inlet/outlet configurations 1 1.1.2. Evolution from single storage tank systems to multiple tank systems 4 1.1.3. Operations of RWH systems 5 1.2. Objectives 5 1.3. Research Scheme 6 Chapter 2. Literature review 8 2.1. Inlet/outlet configurations of RWH systems 8 2.2. Multi-tank RWH systems 9 2.3. Studies on Operations of RWH systems 10 Chapter 3. Effect of inlet/outlet configuration on water quality in a rainwater harvesting tank 11 3.1. Material and methods 11 3.1.1. Experimental Method 11 Experiment 13 3.1.2. Analysis Method: Residence Time Distribution (RTD) 15 3.2. Results & Discussion 18 2.2.1. Effect of Inlet type 18 3.2.2. Effect of inlet height 26 3.2.3. Effect of flow rate 27 3.2.4. Effect of outlet height and initial water level 28 3.2.5. Effect of bottom sediment 29 Chapter 4. The effect of number of tanks on water quality in RWH systems under sudden contaminant input 31 4.1. Material and methods 31 4.2 Results & Discussion 36 4.2.1. Pulse Particle Input 36 4.2.2. Pulse conservative tracer study 43 Chapter 5. Behavior of a sudden inflow of soluble pollutants in multi tank RWH systems and r emedial strategy during operation 48 5.1 Materials and Methods 48 5.2 Results & Discussion 53 5.2.1 Tracer (salt) mass distribution during tank filling 53 5.2.2 Variation of tracer (salt) concentration with drained water volume 55 5.2.3 Variation of tracer (salt) concentration with overflow 58 Chapter. Conclusions 60 6.1 Effect of inlet/outlet configurations 60 6.1.1 Conclusions of the study 60 6.1.2 Limitations & further studies 62 6.2 Effect of number of tanks 62 6.2.1 Conclusions of the study 62 6.2.2 Limitations & further studies 63 6.3 Removal of a soluble pollutant during operations 64 6.3.1 Conclusions of the study 64 6.3.2 Limitations & further studies 64 Publications 66 국문초록 67 Acknowledgement 70 References 73석

Sustainability Analysis of Domestic Rainwater Harvesting Systems for Current and Future Water Security in Rural Mexico

Rainwater harvesting, the act of capturing and storing rain, is an ancient practice that is increasingly utilized today by communities to address water supply needs. This thesis examines whether domestic rainwater harvesting systems (DRWHS) can be a sustainable solution as defined by social, water quality, and technical feasibility for water security in semi-arid, rural environments. For this study, 50 surveys and 17 stored rainwater analyses were conducted in San Jose Xacxamayo, Mexico, in conjunction with my Peace Corps work of implementing 82 DRWHS. Results showed that all DRWHS were socially feasible because of cultural acceptance and local capacity. Water quality analyses showed that four DRWHS contained coliform bacteria; deeming water unfit for human consumption. Technical feasibility, examined through climate analyses, showed an average year-round reliability of 20-30% under current and future rainfall regime. The DRWHS can be a sustainable water supply option with roof expansion and treatment prior to consumption

Green technologies for sustainable water management: Introduction and overview

© 2016 American Society of Civil Engineers. This chapter presents the background, current development and future opportunities of green technologies and issues to facilitate strategic planning of sustainable water management systems. It describes the fundamental concepts and current and future applications of green technologies for sustainable improvement in water management. The chapter discusses the appropriate approaches and policies in achieving sustainable objectives and promoting green design and supplies for water utilization. Sustainable water management has received great attention over recent years because of its substantial benefits to the environment, society, and economy. Improvements in water management are likely to come from green technologies fueled by individual curiosity, dedicated effort, and opportunities within a strategic program supported by national and international agencies, universities, and industries. These innovations can significantly contribute to less nonrenewable resource requirement, reduced carbon footprint, greenhouse gas emissions and costs, minimized water losses, and enhanced removal of contaminants

Management of Urban Waters with Nature-Based Solutions in Circular Cities—Exemplified through Seven Urban Circularity Challenges

Nature-Based Solutions (NBS) have been proven to effectively mitigate and solve resource depletion and climate-related challenges in urban areas. The COST (Cooperation in Science and Technology) Action CA17133 entitled “Implementing nature-based solutions (NBS) for building a resourceful circular city” has established seven urban circularity challenges (UCC) that can be addressed effectively with NBS. This paper presents the outcomes of five elucidation workshops with more than 20 European experts from different backgrounds. These international workshops were used to examine the effectiveness of NBS to address UCC and foster NBS implementation towards circular urban water management. A major outcome was the identification of the two most relevant challenges for water resources in urban areas: ‘Restoring and maintaining the water cycle’ (UCC1) and ‘Water and waste treatment, recovery, and reuse’ (UCC2). s Moreover, significant synergies with ‘Nutrient recovery and reuse’, ‘Material recovery and reuse’, ‘Food and biomass production’, ‘Energy efficiency and recovery’, and ‘Building system recovery’ were identified. Additionally, the paper presents real-life case studies to demonstrate how different NBS and supporting units can contribute to the UCC. Finally, a case-based semi-quantitative assessment of the presented NBS was performed. Most notably, this paper identifies the most typically employed NBS that enable processes for UCC1 and UCC2. While current consensus is well established by experts in individual NBS, we presently highlight the potential to address UCC by combining different NBS and synergize enabling processes. This study presents a new paradigm and aims to enhance awareness on the ability of NBS to solve multiple urban circularity issues.publishedVersio