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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.
401

Small-scale anaerobic digesters in Vietnam - development and challenges: Review Paper

Nguyen, Vo Chau Ngan 06 August 2012 (has links)
Small-scale anaerobic digesters, known as biogas plants, were applied as an optimal livestock waste treatment as well as biogas supply for cooking and lighting demand for small-scale farmers in Vietnam. Although the biogas technology was introduced for nearly 30 years, the number of the constructed biogas plants is still limited. The current development of biogas plants is far below the real demand on livestock waste treatment that has increased significantly. This paper gives a comprehensive overview on the biogas plant development in Vietnam and attempts to address the challenges and discuss appropriate solutions for the further biogas development. / Mô hình lên men yếm khí quy mô nhỏ (được biết với tên hầm ủ khí sinh học) đã được ứng dụng hiệu quả trong xử lý chất thải chăn nuôi cũng như cung cấp nguồn nhiên liệu phục vụ nhu cầu nấu ăn và thắp sáng cho các hộ chăn nuôi nhỏ ở Việt Nam. Mặc dù đã hiện diện gần 30 năm, nhưng số lượng hầm ủ khí sinh học vẫn còn hạn chế. Sự gia tăng số lượng hầm ủ khí sinh học chưa theo kịp với nhu cầu về xử lý chất thải chăn nuôi đang ngày càng gia tăng. Bài báo trình bày các chặng đường phát triển của hầm ủ khí sinh học tại Việt Nam, ghi nhận các thách thức trong việc nhân rộng hầm ủ khí sinh học trong thực tế và thảo luận một số giải pháp để phát triển công nghệ khí sinh học.
402

Solid waste management in Mekong Delta: Review Paper

Nguyen, Xuan Hoang, Le, Hoang Viet 07 August 2012 (has links)
Municipal solid waste (MSW) in Vietnam has been increasing quickly and became one of the most considered environmental problems in Mekong Delta (MD) region covering 13 provinces and municipalities in the south of Vietnam. With a considerably large amount of MSW, the region produces about 5% of the total amount of MSW of the country. The collection rate of solid waste is about quite high (65 - 72%) in the cities and rather low (about 40 - 55%) in the rural areas, with a high content in organic matter (about 60 - 85%). The climate of MD can be characterized as tropical and monsoonal with a high rate of humidity and a strong impact of flooding. Like other regions too, the MSW collection and treatment system is still underdeveloped and rudimentary, with disposal sites being the sole dumping method of the unsorted MSW remaining untreated by any mechanical and biological pre-treatment steps. Within this paper, the current treatment, management and operation of MSW systems are introduced, as well as the identification of advantages and disadvantages, environmental impacts, potential risks of the MSW system within the impact of global climate change. The situation of MSW treatment and management is correlated with the climate change impact and the integrated solid waste management is introduced as a new approach for adapting the environmental protection awareness by considering the climate change for the longterm sustainable development orientation. / Sự gia tăng chất thải rắn ở các đô thị Việt Nam ngày càng nhanh và chất thải rắn đang là một trong những vấn đề môi trường được quan tâm hàng đầu. Đồng bằng Sông Cửu Long (ĐBSCL) nơi có đến 13 tỉnh và thành phố nằm ở phía Nam Việt Nam. Với lượng chất thải không nhỏ, chiếm khoảng 5 % tổng lượng chất thải rắn sinh hoạt của quốc gia. Tỷ lệ thu gom chất thải rắn thấp, chiếm khoảng 65 - 72 % ở thành thị, tỷ lệ này ở nông thôn thấp 40 - 55%, chất thải có hàm lượng hữu cơ cao chiếm khoảng 60 - 85%. Khí hậu nhiệt đới gió mùa với độ ẩm không khí cao và chịu ảnh hưởng lớn của lũ lụt hàng năm. Cũng như các khu vực khác, hệ thống thu gom và xử lý rác thải ở khu vực ĐBSCL còn rất thô sơ và lạc hậu, bãi rác là nơi duy nhất tiếp nhận trực tiếp hổnhợp rác thải không phân loại và qua bất kỳ công đoạn tiền xử lý nào. Trong phạm vi bài viết này, chúng tôi giới thiệu hoạt động vận hành hệ thống quản lý và xử lý rác đô thị trong khu vực đồng thời phân tích các thuận lợi và bất lợi, cũng như các tác động môi trường, những rủi ro tiềm ẩn trong điều kiện ảnh hưởng của biến đổi khí hậu toàn cầu - khu vực ĐBSCL là nơi chịu ảnh hưởng nặng nề nhất. Tình hình quản lý và xử lý rác được cân nhắc trong điều kiện tác động của biến đổi khí hậu, đồng thời quản lý tổng hợp rác thải cũng được đề xuất như một các tiếp cận mới nhằm đáp ứng nhiệm vụ bảo vệ môi trường trong điều kiện biến đổi khí hậu theo định hướng phát triển bền vững lâu dài.
403

Management of organic solid waste from rail operation by the Vietnam railways: the current situation and possible solutions: Research article

Nguyen, Thi Hoai An 15 November 2012 (has links)
The quick social economic development of Vietnam stimulates great demand of quality as well as quantity on transport service by the increasingly growing needs of customer for transportation. The railway passenger transport is currently still an important branch of a country’s transport system because it is safer, more eco-friendly and much more efficient in comparison to another means. However, the increasing of the number of passengers is the main causes of fast increasing waste amount from the rail service. The aim of this paper is to study how the organic waste from rail service is managed and treated today by the Vietnam railways. The paper ends with some proposal solutions for treating and disposing of organic waste by applying renewable energy technologies for climate change mitigation to protect human health and the environment. / Sự phát triển nhanh chóng của nền kinh tế Việt nam dẫn đến nhu cầu vận chuyển hành khách ngày càng tăng mạnh về số lượng cũng như chất lượng dịch vụ. Vận chuyển hành khách bằng đường sắt hiện tại ở Việt nam vẫn đóng vai trò quan trọng trong hệ thống vận tải quốc gia do lợi thế an toàn cao, thân thiện với môi trường và lợi ích cao của nó so với các phương tiện khác. Tuy nhiên sự biến động lớn của lượng hành khách đi tàu là nguyên nhân làm cho lượng rác thải từ các dịch vụ đường sắt cũng tăng mạnh. Bài báo tập trung vào nghiên cứu và làm rõ hiện trạng quản lý chất thải hữu cơ trên đường sắt Việt nam hiện nay cũng như các chiến lược nhằm xử lý chất thải hữu cơ, sử dụng công nghệ năng lượng tái tạo nhằm bảo vệ môi trường, giảm thiểu biến đổi khí hậu.
404

Bioasphalt and Biochar from Pyrolysis of Urban Yard Waste

Hill, Daniel R. 30 January 2012 (has links)
No description available.
405

The Effect of Introducing a Curbside Recycling System on the Recycling Behavior of Households

Särnholm, Jenny January 2022 (has links)
This research investigates whether the implementation of a curbside recycling system has an effect on the behavior of households with regard to the recycling of packaging material in Sweden. Previous research presented in the literature points out that the decision to engage in recycling behavior, rather than free-riding on the contributions of others, is based on the perceived contribution of others. Complying with social norms and the experience of warm-glow constitute forms of utility that are derived from engaging in recycling behavior. The recyclable packaging materials glass, paper, plastic, and metal, as well as the total of these materials, are considered in this study. Recycling data from 247 municipalities for the years 2010-2020 are used to research this topic. The analysis is carried out using a difference-in-difference model with multiple time periods and a model presented by Callaway and Sant’Anna. A positive and significant change in household recycling was found for plastic packaging waste, amounting to an average increase of 1.57-2.92 kilograms per resident per year when the curbside recycling system was introduced. The change in recycling was also positive for paper, but this result was not robust to changes in the original model specification. Significant increases in recycling were found for total recycling, glass, and metal as well. However, it is considered uncertain whether the identifying assumptions that have to be fulfilled to establish causality of the results are satisfied. The introduction of a curbside recycling system increases household recycling because the time and effort that are required to recycle decrease. The results presented in this study are in line with this notion.
406

En fallstudie om hushållens källsortering i Augustenborg (A Case Study on Waste Management in Augustenborg)

Altundal, Sadiye, Gullberg, Meloujane January 2007 (has links)
Hållbar utveckling är en vision som hela världen eftersträvar att uppnå. Hushållsavfallshanter-ing är ett sätt för att uppnå en hållbar samhällsutveckling. Bra kunskap, information och sam-verkan mellan olika aktörer är ytterst nödvändigt för att kunna uppnå en hållbar samhällsut-veckling. Syftet med fallstudiet är att kartlägga en del av stadsdelen Augustenborg i Malmö för att se över hur hushållsavfallshantering fortskrider. Det är även vårt syfte att identifiera möjligheter och hinder för en ökad källsortering i området. Genom enkätundersökning och intervjuer har vi samlat information om hur olika faktorer påverkar avfallshantering i Augus-tenborg. Resultatet visar att det finns olika faktorer som påverkar avfallshanteringssystemet och dessa är inte bara det formella faktorer som till exempel regler och lagar men också andra faktorer som människans attityder har stor betydelse. / Sustainable development has become a major concern all over the world. Household waste management is one of the solutions to attain a sustainable development and community. It is today of great importance to have the proper knowledge, information and coordination be-tween different sectors and organizations in order to attain a sustainable development. This case study aims to investigate an area in Augustenborg, Malmö in order to analyze their existing waste management system. It is even our intention to identify the development pos-sibilities and obstacles of waste management in the area. Through survey and personal inter-views, we were able to gather information on different factors and variables that affect waste management system in Augustenborg. The results suggest that there are various factors that affect waste management, and these are not just formal factors, such as rules and regulations but also other factors, such as human behaviour.
407

Improving Solid Waste Management in Addis Ababa, Ethiopia. Based on the experience from Sweden, Östersund Municipality.

Haile, Hilab January 2016 (has links)
Lack of genuine concern for solid waste management practices and inefficiency of sol-id waste management system is one of the greatest environmental issues in Addis Ab-aba, Ethiopia. The Current Municipal Solid Waste Management System is extremely inefficient and ineffective. An illegal waste dumping, inefficient waste collection, and informal recycling are some of the issues that need to be immediately rectified. There-fore, this study was conducted in order to get a knowledge transfer from a developed country, Sweden, Östersund Municipality. The practical waste management and recy-cling activities undertaking in the city of Östersund have been assessed, evaluated and discussed in the study. Physical site visits, surveys, informal interviews, and group dis-cussions have also been conducted to be able to draw an immensely useful and tangi-ble recommendation for the improvement of Solid Waste Management and Recycling Scheme in Addis Ababa. Based on the experience acquired from Östersund the entire Solid Waste Management system in Addis Ababa has been evaluated and useful dis-cussions, recommendations, and conclusions have been drawn. Besides as recycling is one of the most significant waste management hierarchy components, it should have been given top priority in reducing the amount of waste generation in developing countries like Ethiopia. However, the recycling activities taking place in the country are highly limited and informal. Moreover, evaluation of the potential of recyclable wastes in Addis Ababa, discussion on how and why recycling needs to be given prece-dence and later comparison is made with Östersund Municipality in order to be able to gain knowledge from the Swedish experience. Besides, discussions were made in order to address decisive measures that need to be taken to implement the Swedish experience in the Solid Waste Management and Recycling sector in Addis Ababa Ethiopia in an environmentally friendly and economical way.
408

Utveckling och visualisering av en återvinningsanläggning / Development and visualisation of a recycling plant

Fältholm, Anna, Thomasson, Hugo January 2016 (has links)
Sverige är ett av de länder med högst återvinnings- och skräphanteringsratio. Mängden deponi har minskat mer och mer under de senaste åren och ersatts med fler återvinningsmetoder samt energiåtervinning. Dock så är en hög andel av det material som förbränns och hamnar på deponi fortfarande användingsbart vid återvinning. Därför finns det ett behov att hitta en mer effektiv lösning för materialåtervinning. Rapporten täcker arbetet med att utveckla och visualisera ett koncept för en single-stream återvinningsanläggning som skall kunna appliceras i Sverige. Material och skräptyper har studerats och evaluerats. Detta gav sju olika fraktioner: blandat papper, PE, PP, HDPE, järnhaltiga metaller, icke järnhaltiga metaller samt trä. För dessa fraktioner har sedan maskiner valts ut och sedan 3D-modellerats. Omgivande komponenter som t.ex. trappor och ställningar har även modellerats för att ge ett verkligt intryck av återvinningsanläggningen. För exteriören av anläggningen har fotogrammetri använts för att återskapa en topografi för att sedan integrara byggnaden i topografin. Animationer har gjorts för både exteriören och interiören för att visa hur skräpet kommer till anläggningen, behandlas, och sedan transporteras iväg. Eftersom arbetet har varit på ett konceptuell nivå ges rekommendationer och tips på fortsatt arbete för att kunna verkställa en sådan anläggning i Sverige. / Sweden is one of the countries with the highest recycling and waste processes rates. Over the years the landfill has been reduced and replaced by better recycling and waste-to-energy through combustion. However, a large amount of the waste that goes to to combustion and landfill are still useable if recycled. Therefore there is a demand of finding a more efficient solution for recycling material. The report covers development and visualisation of a concept for a single stream recycling plant that could be applied on waste in Sweden. Materials and waste has been studied and evaluated to find seven fractions to recycle from a mixed waste stream: mixed paper, PE, PP, HDPE, ferrous metals, non ferrous metals, and wood. Machines were selected and 3D modelled. Photogrammetry was used to recreate a topography of the surroundings to put the plant in. Animations were made of the exterior and interior demonstrating how the waste arrives to the plant, gets sorted, and finally transported away. Since the work is on a conceptual level the report provides recommendations and future work for how to further develop the plant, and finally build it in Sweden.
409

Life cycle assessment of industrialized lithium-ion battery recycling : Mechanical and hydrometallurgical treatment from an ex-ante perspective / Livscykelanalys av industrialiserad återvinning av litiumjonbatterier

Balsvik, Jonathan January 2020 (has links)
As the use of lithium-ion batteries exponentially increases through demand for electric vehicles and energy storage systems, so will the need for end-of-life treatment subsequently increase. Recycling the valuable materials from batteries in an efficient and extensive fashion could decrease the environmental impacts of batteries. Northvolt AB is a Swedish battery manufacturer currently constructing a Gigafactory in Skellefteå and is furthermore developing a recycling process, focused on hydrometallurgy, with full-scale recycling operations a couple of years away. In order to assess the environmental hotspots of the process, with a focus on greenhouse gas emissions, a life cycle assessment was conducted with data from Northvolt AB. This data was based on learnings from a pilot plant currently under operation but scaled up to industrial level for an ex-ante type of assessment. The industrial operations at Skellefteå represented +95% of the climate change impact, the remainder arising from a European collection point. The most significant impact driver was waste management (56,5% of the climate change impact category), specifically incineration of recovered materials and residuals. The results indicate that harnessing renewable energy in both the direct operations and the supply chain is of high importance. Chemicals (27%) and electricity (7%) had extensively smaller emissions thanks to the harnessing of renewable energy in both direct operations and the supply chain, compared to electricity mixes with large shares of fossil fuels. Furthermore, large variability was found in impacts of recovered materials depending on the chosen allocation method. The benefit of the Revolt process is likely to be affected by ongoing research projects to recycle and upgrade materials that are currently sent to incineration. For an as high environmental efficiency as possible, it is important that the process make as much use of all the recovered materials as possible, find efficient waste treatment processes, and continue to source from production using as electricity mixes with high shares of renewable energy. / Givet att användningen av litium-jon batterier ökar exponentiellt, drivet av efterfrågan på elfordon och energilagringssystem, så kommer behovet av att avfallshantera utgående batterier att öka. Att återvinna värdefulla material från batterier på ett effektivt och omfattande sätt skulle kunna minska batteriernas miljöpåverkan sett över hela dess livscykel. Northvolt AB är en svensk batteritillverkare som bygger en fabrik i Skellefteå och parallellt utvecklar en återvinningsprocess med fokus på hydrometallurgi, med fullskalig återvinning planerad. För att utvärdera vilka aspekter av processen som driver dess miljöpåverkan, med fokus på utsläpp av växthusgaser, gjordes en livscykelanalys med data från Northvolt AB.  Datainventeringen baserades på lärdomar från en pilotanläggning som för närvarande är under drift, men skalades upp till industriell nivå för en förhandsbedömning. Industriverksamheten i Skellefteå stod för +95% av klimatpåverkan, resten härrör från en europeisk insamlingsplats av utgående batterier. Den viktigaste bidragsfaktorn för klimatutsläpp var avfallshantering (56,5 % av utsläppen), särskilt förbränning av återhämtade material och restprodukter. Resultaten visar att det är av stor betydelse att utnyttja förnybar energi i både den direkta verksamheten och leverantörskedjan. Kategorierna kemikalier (27%) och el (7 %) hade betydligt lägre utsläpp tack vare att förnybar energi utnyttjades, i jämförelse med nationella elmixer med större andelar fossila bränslen.  Vidare konstaterades stor variation i resultatet av miljöpåverkan på återvunnet material beroende på vald allokeringsmetod. Fördelarna med Revoltprocessen kommer sannolikt att påverkas av pågående forskningsprojekt för att återvinna och uppgradera material som för närvarande skickas till förbränning. För minskade klimatutsläpp är det viktigt att processen i så stor utsträckning som möjligt materiellt återvinner alla utgående material, hittar effektiva avfallshanteringsprocesser och fortsätter att etablera en leverantörskedja som producerar med stora andelar förnybar energi.  Utöver att utvärderingen gjordes med preliminära data resonerades avfallshanteringen vara den enskilt största källan till osäkerhet. Framtida livscykelanalyser skulle dra nytta av uppmätt data när den industriella anläggningen är operationell, samt vidga analysen med mer utförlig datainhämtning från relevanta avfallsprocesser och återvinningstekniker.
410

Avfallshantering i Stockholms skärgård : En studie i Värmdö kommun / Waste Management in the Stockholm Archipelago : A Värmdö Municipality Case Study

Hallberg, Anna, Östlund, Emma January 2020 (has links)
Syftet med den här studien är att utvärdera det befintliga avfallssystemet på de kärnöar som benämns i den Regionala Utvecklingsplanen för Stockholmsregion (RUFS 2050) tillhörande Värmdö kommun, en skärgårdskommun öster om Stockholm. Ett hållbarhetsperspektiv ligger till grund för kartläggningen av området och innefattar aspekter som social, ekonomisk och ekologisk hållbarhet vilket genomsyrar hela rapporten. Avfallstyperna som har studerats är rest-, och matavfall samt förpackningar och returpapper som behandlas genom materialåtervinning. Rapporten är baserad på en litteraturstudie kompletterad med intervjuer för att skapa en mer nyanserad bild av systemet. Även om det idag finns etablerade system för hantering av restavfall saknas ett system för matavfall och materialåtervinning som täcker hela Värmdö kommun. Detta resulterar i en ökad mängd restavfall vilket leder till bristfälliga arbetsförhållanden. Andra svårigheter med avfallshanteringen i skärgården är de långa transportsträckorna över havet som är tidskrävande, kostsamma och har en negativ miljöpåverkan. På grund av de olika förutsättningar bland skärgårdsöarna krävs det ett flexibelt och välanpassat system vilket leder till en hög servicenivå. Trots att många av de boende i skärgården upplever systemet som välfungerande tydliggör denna studie att det krävs åtgärder som förbättrar arbetsmiljön och minskar systemets miljöpåverkan. Utöver att etablera nya system för insamling av matavfall, förpackningar och returpapper krävs åtgärder som gynnar återanvändning samt minimerar mängden producerat avfall för att i linje med EU- direktiv skapa ett hållbart avfallssystem i Värmdö kommuns skärgård. / The purpose of this study is to evaluate the existing waste management system on the main islands of Värmdö municipality, which is a part of the Stockholm archipelago, as described in the regional development plan for the greater region of Stockholm (RUFS 2050). Throughout the report, this evaluation will be made from a sustainability perspective including social, economic and ecological aspects. The types of waste that are subject to review are general waste, food waste and recyclables such as products made from plastic, paper, glass and metal as well as newspapers and magazines. The report is based on a literature review that is complemented by interviews, providing a nuanced image of the complete system. Currently established systems for managing general waste in the archipelago exists but as the system for food waste and recycling does not include this region, they require future development in order to extend to the entire municipality. As a result, much of the food and recyclable waste ends up in the general waste, leading to inadequate working conditions within that system. Moreover, transportation between the islands and the mainland is costly, time consuming and has a negative environmental impact. As such, the waste management system must be flexible and adaptable to the varying conditions of the islands in order to deliver a high level of service. This study shows that there is a need to improve working conditions and reduce the negative environmental impact of the municipality’s waste management system. Besides implementing new systems for managing food and recyclable waste, action must be taken to promote reuse and minimize the amount of waste produced. This would ensure alignment with EU directives as well as make the whole system more sustainable.

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