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.

A fast increase of municipal solid waste (MSW) has become the most concerning environmental problem in Vietnam, especially in the Mekong Delta region, that is considered one of the most vulnerable deltas to climate change in the world. There are 12 provinces and one central city in MD that occupy about 12% of the whole area of the nation with 5% of MSW generated. However, there is no currently effective management system in place for treatment and management of MSW in the MD. Landfill is the sole treatment option for MSW right now. With a low-level plain, MD is facing the most serious environmental problem in the near future with an effect of climate change and sea level rising. The landfill should not be considered for long-term use in this area. Suitable treatment options for MSW should be applied together with other solutions for reuse, recycling and reduction of MSW as well as pollution prevention issue. An integrated MSW management approach in adaptation to climate change is considered necessary. / Sự tăng nhanh chất thải rắn đã trở thành vấn đề vấn đề môi trường được quan tâm nhất ở Việt Nam, đặc biệt là ở khu Đồng bằng Sông Cửu Long một trong những đồng bằng dễ bị tổn thương bởi sự biến đổi khí hậu nhất trên thế giới. Đồng bằng Sông Cửu Long có 12 tỉnh và một thành phố trực thuộc trung ương, chiếm 12% diện tích của cả nước với khoảng 5% lượng chất thải rắn phát sinh. Tuy nhiên, hiện nay chưa có một hệ thống quản lý hiệu quả cho chất thải rắn ở khu vực. Bãi rác là lựa chọn xử lý duy nhất ở thời điểm này. Với cao độ thấp, Đồng bằng Sông Cửu Long đang đối mặt với ảnh hưởng nghiêm trọng của các vấn đề môi trường trong tương lai gần bởi ảnh hưởng của sự biến đổi khí hậu và nước biển dâng. Về lâu dài bãi rác không nên sử dụng ở khu vực này. Các lựa chọn xử lý thích hợp cho chất thải rắn cần được áp dụng cùng với các giải pháp khác như tái sử dụng, tái chế và giảm thiểu chất thải rắn cũng như các giải pháp ngăn ngừa ô nhiễm. Cách tiếp cận quản lý tổng hợp chất thải rắn nhằm ứng phó sự biến đổi khí hậu cần được xem xét.

This study determined the polychlorinated dibenzo-p-dioxins/ dibenzo- furans (PCDD/Fs) and 22 metals contents in ash in the super heater (SH), economizer (EC), semi-dryer absorber (SDA), fabric filter (FF), fly ash pit (FAP) and bottom residue (BR) in a municipal solid waste incinerator (KTMSWI). Experimental results showed that average PCDD/FS contents in ash samples from the SH, EC, SDA, FF, FAP and BR were 0.102, 0.788, 0.210, 1.95, 2.04 and 0.0218 ng I-TEQ /g, respectively. PCDD/Fs content was very low in the SH and BR due to high temperatures (around 461¢XC in the SH and 914¢XC in combustion chamber). Conversely, total PCDD/Fs content was significantly high in ash samples from the EC (around 340¢XC), mainly because the temperature is within the favorable range of 250-400¢XC for PCDD/FS formation due to de nova reformation mechanisms. Although the SDA operated at 245¢XC, the PCDD/FS content decreased very significantly, mainly because the temperature was relatively low and because calcium carbonate was introduced into flue gases to dechlorinate and dilute chlorine-containing species. PCDD/Fs were captured by the active carbon in the FF. Furthermore, the duration that fly ash remained in the FF was longer than that for other incinerator units, and thus causing an increasing trend of PCDD/Fs level downstream (except the SDA). Total PCDD/Fs emission factors (£gg /ton-waste; £gg I-TEQ /ton-waste) in ash samples from different units were: SH (42.3; 0.846), EC (326; 6.12 ), SDA (58.1; 1.10), FF (1540; 61.3), FAP (2950; 107) and BR (537; 4.31). Most PCDD/Fs in ash were contributed by the FF (about 56%), and the generation of PCDD/Fs in ash was significant (about 35%) during the transfer process from different units to the FAP. A strong and positive correlation in a logarithmic form existed between PCDD/Fs and chlorine (Cl-) contents in ash. The results showed that principal metals in the incinerator ash were Al, Fe, Zn, Ba, Pb and Cu. On average, these six metals accounted for 96.6%, 96.8%, 97.0%, 94.2% and 96.7% of the total metals in SH, EC, SDA, FF and BR ash, respectively. The emission factors of individual metals from different units were obtained. Volatile metals, such as Cd, Sn, Sb, Hg and Pb, were mostly in fly ash, while lithophilic metals, such as Al, Fe, Ti, V, Cu, Mn, Fe, Co, Ni, Cu, Sr, Mo, Ag, Ba and Cr+6 were mainly in bottom ash. Distribution ratios for total metals in SH, EC, SDA, FF and BR ash were 4.87%, 4.26%, 2.89%, 8.17% and 79.81%, respectively. That is, about 20.2% of total metals were in fly ash and most metals (about 79.8%) were in bottom ash. The Pb content in EC ash and Hg content in FF ash were between alarm contents and maximum legal limits, while Cd and Pb contents in FF ash exceeded the maximum legal limits. The existing transportation system for transferring fly ash from different units to a fly ash pit should be modified for recycling the valuable metals. Ash with less than the alarm content for metals content, such as ash from the SH, SDA and BR, can be reused. Ash with metals exceeding the alarm contents, such as ash from the EC and FF, should be collected and transferred to a different fly ash pit for further treatment, such as metal recycling.

Municipal waste management aims to collect waste from people and businesses in a sustainable manner. Today's waste management relies on an old container system which is simple and flexible. There are some problems with this type of management for both waste generators and collectors. The working environment is not the best for municipal waste collectors, there is heavy lifting and risk elements in the handling of containers and bags. There are also risks involved with heavy vehicles moving in sensitive areas such as residential areas and around schools. Forecasts show that most urbanized areas are expected to grow further for some time. This creates problems of increasing waste volumes, thereby increasing traffic. This makes it interesting to evaluate new and existing solutions of the collection and transportation of municipal solid waste. The study aims to identify the current municipal solid waste management theories and evaluate the opportunities that exist to develop the theory forward with focus on the collection in urban areas. The study intends to review whether it is economically feasible to implement automated vacuum systems in existing infrastructure. The theory shows that it is often possible to implement this in new construction projects, but the research is vague and inadequate regarding implementation in existing infrastructure. The case study examines whether implementation of an automated vacuum collection system is possible in central Gothenburg. The analysis assesses the financial feasibility of the implementation. Specifically, the unused surface of the refuse rooms can be utilized differently, thus reducing the costs that arise initially. The study shows that it will be profitable to implement an automated vacuum system in the study area since the initial investment can be offset through the alternative use of the floor space in the waste rooms. The study results suggest that other areas in existing infrastructure can implement similar solutions without economic losses.

Marginal soils, including loose sands, soft clays, and organics are not adequate materials for construction projects. These marginal soils do not possess valuable physical properties for construction applications. The current methods for remediation of these weak soils such as stone columns, vibro-compaction, etc. are typically expensive. Waste materials such as scrap tires, ash, and wastewater sludge, offer a cheaper method for stabilizing marginal soils. As an added benefit, utilizing waste materials in soil stabilization applications keeps these materials from being dumped into landfills, thereby saving already depleting landfill space. Included in this report is an extensive investigation into the current state of research on waste and recycled materials in construction applications. Also included is an investigation on actual implementation of this research in construction projects. Upon completion of this investigation, an effort was made to determine waste materials specific to the state of Florida (waste roofing shingles, municipal solid waste ash, waste tires, and paper mill sludge) that could be used in stabilizing marginal soils through soil mixing techniques. Changes in the engineering properties of soils as a result of adding these waste materials were studied and recommendations on implementing these effects into construction applications are offered.

In today’s society large quantities of waste is produced. In Sweden this is reused as fuel for incineration processes where electricity and district heating are generated. However, during this process two hazardous by-products are formed, namely slag and fly ash. These contain relatively high concentrations of heavy metals, which make them harmful to the environment if not taken care of, but also make them valuable resources if the metals could be extracted and reutilized. One possible way to extract metals from the waste products is to use electrochemical methods. In order to implement these techniques on an industrial scale, there are several parameters that have to be considered. One important parameter is the choice of material of the electrode, which needs to have a large surface area, a high chemical inertness and electrical conductivity, and preferably also a reasonable price. A material that fulfills these qualifications is reticulated vitreous carbon (RVC), and therefore the extraction efficiency of this porous material has been evaluated in this thesis. Studies were also performed to evaluate how several other parameters affected the extraction efficiency, since this does not rely on the choice of electrode material alone. The results showed that RVC is suitable as electrode material for efficient metal extraction from fly ash. The most efficient electrode combination was RVC with a pore size of 10 pores per linear inch as working electrode, stainless steel as counter electrode, and Ag/AgCl as reference electrode. Both the amperometric and galvanostatic experiments extracted equal amounts of copper within the same time interval, which means that the choice of using either controlled potential or controlled current for an efficient extraction of copper was not of significant importance. The mass transfer rate for copper was 0.12 mg·h-1·cm-2 in both methods, where an electrolyte of 200 ml was used with an initial copper concentration of 50 mg/l. Regarding stirring of the electrolyte, circulation in the solution is an advantage, but not critical for an efficient reduction. The extraction efficiency for one particular metal did not seem to be affected by the presence of other metals in the electrolyte. It was also shown that a selective extraction of metals was possible by applying different potentials. Lastly, an experiment with fly ash was performed, with the optimal conditions and electrode combination based on the previous experiments. This yielded a mass transfer rate of 0.59 mg·h-1·cm-2 for zinc using an electrolyte of 200 ml, which initially contained 595 mg/l of zinc.

Over the last few decades, thermal treatment of municipal solid waste (MSW) has been strongly opposed in North America. The reasons for public opposition are complex and could vary from community to community. Typically, public antagonism towards thermal treatment option is clearly revealed during the planning process of energy-from-waste facilities. Concepts such as NIMBY (Not In My Back Yard) have become synonymous with the siting of MSW thermal treatment facilities. Given the highly controversial nature of such projects, effective organization and conduct of the municipal planning process is of high importance. The literature suggests that public opposition can be fuelled by the perception of unfair outcome and unfair planning process. Therefore, the equity dimension of the planning process has gained importance. This research explores the planning processes surrounding the development of thermal treatment plants for MSW in the province of Ontario, Canada by focusing on the equity dimension. The research aims to reveal the role and the nature of substantive equity, procedural equity, and cost and time efficiency, as well as the role of contextual elements in planning processes. Additionally, the research intends to provide recommendations on the effective incorporation of the equity dimension into the waste management planning processes. Through a review of the literature on planning controversial facilities with a focus on waste disposal plants, it was revealed that the clear delineation of substantive and procedural equity as well as the identification of the main elements that fall under these notions are absent. Different studies present various elements of substantive and procedural equity, but they fall short in consolidation and analysis of linkages among the elements. In addition, it was revealed that the study of the contextual elements in relation to substantive and procedural equity has been quite limited. Three research questions were identified that were informed by two assumptions derived from the consulted literature. To answer the research questions, three cases of planning thermal treatment plants in Ontario were investigated using qualitative research methods. The first case studied the Halton region thermal treatment project that was initiated in 2006 but was soon dropped without reaching the stage of full environmental assessment. The second case study focused on the Niagara-Hamilton thermal treatment project that was a joint effort between the city of Hamilton and the regional municipality of Niagara to find a local solution to the waste problem. An environmental assessment was conducted; however, before its completion the parties decided to stop the project and concentrate on other waste management alternatives. Finally, the third case studied the Durham-York thermal treatment project that underwent a full environmental assessment process and is currently close to completion. This research contributes towards expanding the conceptual discourse about the role of equity in planning waste disposal facilities with a particular emphasis on thermal treatment plants. More specifically, the thesis contributes towards delineating the notions of substantive and procedural equity and distinguishing their elements. It introduces the notion of context and explores those contextual elements that influence substantive and procedural equity during planning processes for thermal treatment facilities. As a result, the thesis develops a comprehensive analytical framework that consolidates the major elements that fall under the domains of substantive equity, procedural equity, and context that have previously been dispersed in the literature. In addition, the research establishes linkages among the elements within each domain and across domains. Based on the findings of the case studies, the notion of distributional equity is reconsidered. Whereas the distributional aspect of the equity dimension is undoubtedly important, the thesis concludes that the substantive equity should go beyond the locational aspect of planning. The existence of cross-domain linkages and their importance and diversity confirms that the notion of equity should be studied and discussed in broader terms which acknowledge not only procedural or distributional issues, but also contextual elements and efficiency questions. The existing scholarship places particular emphasis on locational considerations (siting) and procedural issues; however, it fails to present a comprehensive and multidimensional view of equity and explain how this is embedded within the broader context. This research is an attempt to present equity with all its diversity and complexity and build a foundation upon which further work in this direction can be conducted. More broadly, this research contributes to the better understanding of the perceptions and motivations behind public opposition towards infrastructure projects, and particularly waste management facilities. Given the complex nature of public opposition phenomenon, the research addresses the need to build an in-depth understanding of public motivations and perceptions that shape attitudes towards proposed projects.

Land application of biosolid or industrial compost raises concerns regarding heavy metal accumulation in soils, plants and free-ranging livestock. A strip-split plot design evaluated two levels of sewage sludge (22/44 t ha-1) and municipal solid waste (21/42 t ha-1) compared to nitrogen fertilizer and an unfertilized control. Treatments were evaluated with three levels of limestone (CaCO3 at 0, 3 and 6 t ha-1) over two years corn seeded no-till. Swiss Chard cultivated in field soil samples within a greenhouse monitored heavy metal bioavailability. Compost amended soil was incorporated into chicken feed to simulate soil ingestion in a free-range production system. Compost application increased total soil Pb over time yet decreased both available soil and corn plant Cu levels over time. No heavy metal accumulation was observed in Swiss Chard or poultry tissue. Biosolid composts containing elevated Cu or Pb levels can be safely used for crop or free-range broiler production.

The significant generation of municipal solid waste (MSW) has become a controversial global issue. Pyrolysis and gasification technologies for treating rejects from solid waste disposal sites (SWDSs), for which over 50 % of MSW is attributed to combustible species, have attracted considerable attention. MSW is an alternative energy source that can partly replace fossil resources; there is an increasing awareness that global warming caused by the utilization of fossil resources is occurring. The goal of this thesis is to realize the efficient and rational utilization of MSW and decrease the harmful impact of pollutants, such as dioxin, HCl, and CO2, on the environment. To achieve this goal, some fundamental studies have been experimentally and numerically conducted to enhance the understanding of the properties of municipal solid waste thermal conversion. In this thesis, the pyrolysis behaviors of single pelletized recovered fuel were tested. A detailed comparison of the pyrolysis behaviors of typical recovered solid waste and biomass particles was conducted. A swelling phenomenon with a swelling ratio of approximately 1.6 was observed on the surface of pelletized recovered fuels. Subsequently, a particle model was constructed to describe the thermal conversion process for large recovered fuel particles that are composed of a high fraction of polyethylene (PE) and a comparable low fraction of cardboard. The results indicate that an understanding of the heat transfer mechanism in highly porous and molten structures and the selection of a heat transfer model are crucial for accurate prediction of the conversion process. MSW pyrolysis is a promising method for producing liquid products. With the exception of lignocellulosic materials, such as printing paper and cardboard, PE, polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC) are the six main polymers in domestic waste in Europe. Characterization studies of the products obtained from these individual components, such as PE, PET, PVC, printing paper, and cardboard, have been conducted on a pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) system and a fixed-bed reactor. The possible pathways for the formation of the main primary/secondary products in rapid and conventional pyrolysis were also discussed. MSW steam gasification with CaO was performed in a batch-type fixed-bed gasifier to examine the effect of CaO addition on the heat transfer properties, pollutant removal, and devolatilization and char gasification behaviors in the presence of steam. A new carbon capture and recycle (CCR) system combined with an integrated municipal solid waste system was proposed. The foundation of the system is the development of a novel method to remediate CO2 using a high-temperature process of reforming CH4 and/or O2 and/or H2O without catalysts. Thermodynamic and experimental studies were performed. High temperatures significantly promoted the multi-reforming process while preventing the problem of catalyst deactivation. Potential improvements in the efficiency of the novel technology can be achieved by optimizing the reforming reactants. Landfill gas (LFG) and fuel gas from bio-waste treatment contain a considerable fraction of CH4, which may be a source of CH4 for this process. / <p>QC20141028</p>

To ensure stability of a construction the physical properties of its components have tobe well known. In a landfill, waste presents the largest structural element and controlsboth the stability and integrity of the lining system. In spite of this critical role there is adearth of knowledge on behaviour of waste as an engineering material. Wastevariability and changes in waste stream aggravate the assessment of wastemechanical properties.In a literature review the main influences on shear behaviour of municipal solid waste(MSW) were identified. Design values and recommendation for shear parameter weresummarised. To assess mechanical behaviour in a systematic way the use of aclassification system was deemed crucial for a comparison of different findings fromliterature and a categorisation of waste in regard to its composition. A framework for aclassification system was introduced. Main elements of a comprehensive classificationsystem were identified in a literature review and discussed, and data from literaturewas applied to the classification framework. For the validation of a classificationsystem, municipal solid waste was examined in an in-situ waste sorting analysis andalso applied to the framework.The findings from the waste sorting and the classification system were also used todevelop a family of synthetic waste to gradually examine the influencing factors onwaste mechanical behaviour. For this, the materials, size ranges and shapes of wastecomponents identified in the waste sorting analysis were reduced to a minimum butstill representative amount. A range of synthetic waste compositions was engineeredand tested in a large-scale shear device. Compression tests were also conducted in alarge compression cell. The results from the laboratory testing were compared tovalues from the literature and MSW mechanical behaviour was subsequentlydiscussed in view to potential changes from changing waste streams.The results from shear and compression tests (constrained and shear modulus) onsynthetic waste were linked to the classification system and trends of the mechanicalbehaviour in relation to the tested synthetic waste compositions were identified.A framework for classifying MSW and comparing waste mechanical behaviour waspresented and demonstrated. A family of synthetic wastes was engineered and testedin shear and compression tests. The results were comparable to values from theliterature. Further research is recommended to refine the synthetic waste and theclassification.