The use of renewable waste for bioenergy production is in discussion because of the concurrence to the food or animal feed. The treatment of organic waste is necessary in order to keep clean the environment. The combination of those proposals, the waste utilization and the production of renewable energy can be combined with several techniques. In Vietnam the energy demand will increase rapidly in the next years, because a lot of people do not have access to electricity. The development of power sources is limited mainly to large central power plants using hydropower and traditional fossil fuels. So in the country there exists a considerable potential for sustainable energy sources like biomass and residues. The biogas potential is large due to the high livestock population. There are more than 30 million animals in farms, mostly pigs, cattle, and water buffalo. There is a high potential for biogas utilization. Biogas production is economic in small and in big plants, so household biogas digesters are one opportunity for production of renewable energy in small villages or cities with a high livestock population. The advantage of anaerobic treatment of organic waste is the work in closed loops. The treatment of organic waste and the utilization of digested sludge from wastewater treatment plants are samples for the circulation of materials after use. The remaining materials can be used in the natural circulation process, because the nutrients such as nitrogen, phosphorous and carbon, and also trace elements remain in the digested matter. In biogas plants a huge variety of substrates can be used. The adaption of biogas technology to the special conditions of the substrates, the increase of the prices for energy, the aim to replace fossil energies with renewable energies will be forced in the next years. / Việc sử dụng chất thải có thể tái tạo được để sản xuất năng lượng sinh học là vấn đề còn đang được thảo luận vì sự cạnh tranh với thức ăn hoặc thức ăn cho động vật. Việc xử lý các chất thải hữu cơ là cần thiết để giữ sạch môi trường. Sự kết hợp của các đề xuất đó, tận dụng các chất thải và sản xuất năng lượng tái tạo có thể có thể được kết hợp với một số kỹ thuật. Ở Việt Nam, nhu cầu năng lượng sẽ tăng lên nhanh chóng trong những năm tiếp theo, bởi vì rất nhiều người vẫn chưa có điện sử dụng. Sự phát triển của các nguồn năng lượng chỉ giới hạn chủ yếu là các nhà máy điện lớn trung tâm sử dụng thủy điện và các nhiên liệu hóa thạch truyền thống. Vì vậy, trong nước tồn tại tiềm năng đáng kể cho các nguồn năng lượng bền vững như sinh khối và những nguồn khác. Tiềm năng khí sinh học lớn do quần thể động vật nuôi rất lớn. Có hơn 30 triệu động vật trong trang trại, chủ yếu là lợn, bò, trâu nước. Tiềm năng sử dụng khí sinh học rất cao. Sản xuất khí sinh học rất có hiệu quả kinh tế trong các nhà máy nhỏ và lớn, do đó, các thiết bị phản ứng tạo khí sinh học ở các hộ gia đình là một cơ hội để sản xuất năng lượng tái tạo trong các thành phố hay làng mạc nhỏ với số lượng lớn các gia súc được chăn nuôi. Ưu điểm của việc xử lý kỵ khí các chất thải hữu cơ là làm việc trong vòng khép kín. Việc xử lý các chất thải hữu cơ và sử dụng bùn phân hủy từ các nhà máy xử lý nước thải là các ví dụ cho việc tuần hoàn các vật chất sau khi sử dụng. Các vật chất còn lại có thể được sử dụng trong quá trình tuần hoàn tự nhiên, vì các chất dinh dưỡng như phốt pho, nitơ và carbon, và cả các nguyên tố vi lượng vẫn tồn tại trong nguyên liệu đã phân hủy. Trong các nhà máy khí sinh học, rất nhiều loại chất nền có thể được sử dụng. Sự cải tiến công nghệ sản xuất khí sinh học theo các điều kiện đặc biệt của các chất nền, sự gia tăng của giá năng lượng, mục đích thay thế nguồn năng lượng hóa thạch bằng năng lượng tái tạo sẽ là bắt buộc trong những năm tới.

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.

In this project, by adding selected co-substrates and by incorporating optimum pre-treatment strategies, four experimental phases were conducted to assess the enhancement of biogas production from anaerobic co-digestion using wastewater treatment plant sludge as the primary substrate. In the first phase, the feasibility of using municipal organic wastes (synthetic kitchen waste (KW) and fat, oil and grease (FOG)) as co-substrates in anaerobic co-digestion was investigated. KW and FOG positively affected biogas production from anaerobic co-digestion, with ideal estimated substrate/inoculum (S/I) ratio ranges of 0.80-1.26 and 0.25-0.75, respectively. Combined linear and non-linear regression models were employed to represent the entire digestion process and demonstrated that FOG could be suggested as the preferred co-substrate. The effects of ultrasonic and thermo-chemical pre-treatments on the biogas production of anaerobic co-digestion with KW or FOG were investigated in the second phase. Non-linear regressions fitted to the data indicated that thermo-chemical pre-treatment could increase methane production yields from both FOG and KW co-digestion. Thermo-chemical pre-treatments of pH=10, 55°C provided the best conditions to increase methane production from FOG co-digestions. In the third phase, using the results obtained previously, anaerobic co-digestions with FOG were tested in bench-scale semi-continuous flow digesters at Ravensview Water Pollution Control Plant, Kingston, ON. The effects of hydraulic retention time (HRT), organic loading rate (OLR) and digestion temperature (37°C and 55°C) on biogas production were evaluated. The best biogas production rate of 17.4±0.86 L/d and methane content 67.9±1.46% was obtained with thermophilic (55°C) co-digestion at HRT=24 days and OLR=2.43±0.15 g TVS/L•d. In the fourth phase, with the suitable co-substrate, optimum pre-treatment method and operational parameters identified from the previous phases, anaerobic co-digestions with FOG were investigated in a two-stage thermophilic semi-continuous flow co-digestion system modified to incorporate thermo-chemical pre-treatment of pH=10 at 55°C. Overall, the modified two-stage co-digestion system yielded a 25.14±2.14 L/d (with 70.2±1.4% CH4) biogas production, which was higher than that obtained in the two-stage system without pre-treatment. The positive results could provide valuable information and original contribution to justify full-scale investigation in a continuing research program and to the field of research on anaerobic co-digestion of municipal organic wastes. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2012-09-20 09:00:09.719

Many of the current methods of assessing anaerobic biodegradability of solid samples require sample modification prior to testing. Steps like sample drying, grinding, re-drying and re-grinding to 2mm or less make the test results difficult to apply to field conditions and could lead to oxygen exposure, possibly distorting the results. Finally, because of a small sample size of about 10-50g w/w, the test result may not be representative of the bulk material. A new tool dubbed ‘tube’ has been developed, made of 10 cm diameter PVC pipe measuring 43.5 cm long with 3600 ml capacity with caps at both ends. For easy sample introduction, one endcap is fixed while the other is screw capped. A distinctive feature is the wide neck opening of about 10 cm where solid samples can be introduced as is, without further sample modification. Research has proven the tube applicable across various types of solid organic waste and conditions provided that a suitable organic loading rate is determined. The tube is best operated using 5-7 days pre-digested digested sewage sludge as seed, with minimal mixing and without the addition of nutrients or alkali solution. The test result can be obtained within 4-6 days to 20 days, signifying a 50-75% and 95% substrate degradation, respectively. Irreproducibility seen in some experiments may not only be a function of the seed and the substrate. The organic loading rate (OLR) at which the test is conducted is also influential especially if test is conducted closer to its maximum OLR tolerance where anaerobic process is more erratic. The performance of a continuous reactor digesting on a similar substrate can be estimated using this new tool. Food waste is established by the tubes to have an ultimate methane potential (B0) of 0.45L CH4/g VS. The same substrate when digested in a continuous reactor will produce about (B) 0.32 L CH4/g VS. The first order rate constant for both systems; batch and continuous are identical at 0.12 to 0.28 d-1. First order kinetics is efficient at modelling the anaerobic degradation when the process is healthy but may be less reliable under an unstable process. This research recommends the use of kinetics in combination with the experimental data (e.g. HRT, OLR, yield) when planning and designing an industrial plant to avoid overdesign and unnecessary building, maintenance and operating costs.

The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press. All three technologies hadthe potential to deal with technical hindrances of treating certain waste types with anaerobicdigestion.With ORWARE, life cycle assessment was made by simulations of various wastemanagement scenarios. A total of nine scenarios were simulated for the waste management ofthree different types of wastes: Bio sludge, fibre sludge and food waste, with three scenariosfor each waste type. Bio sludge is microbial sludge from biological waste water treatment.Fibre sludge is lignocellulosic sludge mainly from the pulp and paper industries. Food wasteis generally considered to be the unwanted part of food from households, restaurants and foodindustry.Three primary waste management scenarios, one scenario for each waste type, which includedpretreatment and anaerobic digestion, were simulated. There was a “bio sludge scenario” withultrasonication pretreatment, a “fibre sludge scenario” with thermal hydrolysis pretreatment(THP) and a “food waste scenario” with screw press pretreatment. The rest of the ninescenarios were assessed as comparative references to the three primary ones. These scenariosrepresented conventional methods of waste management or variations of the primaryscenarios.The resulting life cycle assessments show that anaerobic digestion of some organicwastes produces about the same amount of greenhouse gases, acidifying pollutants andeutrophying pollutants as incineration does (where the heat from incineration is made useful).The biggest downside of the anaerobic digestion waste management process is the electricityuse needed for pretreatment and for heating the anaerobic digestion. An electricity cost that inthis case is assumed to be provided through coal power, which is a common assumption whenassessing the impact of margin power utilization in life cycle assessment. If that assumptioncould instead be that the electricity is provided by a less polluting power source, the anaerobicdigestion alternative could lessen the overall pollution since the methane is commonly used asa renewable substitute for fossil fuels.In this master thesis project the ecological and economical benefits and costs of managingorganic waste through pretreatment and anaerobic digestion were assessed. These benefits andcosts were compared to conventional waste management in Sweden. The comparison showsthat anaerobic digestion of organic waste is beneficial for reduction of global warming butlikely has a greater economical cost than the conventional methods, e.g. incineration. / Syftet med det här examensarbetet var att utveckla datormodeller av några sannoliktimplementerbara förbehandlingstekniker och att uppskatta de potentiella vinsterna med atthantera organiskt avfall genom förbehandling och rötning ur ett systemperspektiv. Förändamålet har ett datorprogram som heter ORWARE använts. ORWARE (organic wasteresearch) är ett dator/beräkningsprogram för livscykelanalys av avfallshantering. I sambandmed det här arbetet har ORWARE kompletterats med tre nya modeller avförbehandlingstekniker: ultraljud, termisk hydrolys och skruvpress. Alla dessa tre tekniker harpotentialen att åtgärda tekniska hinder för att röta vissa typer av organiskt material.Med ORWARE gjordes därefter livscykelanalyser på olika avfallshanteringsscenarier. Totaltnio scenarier simulerades för hanteringen av tre typer av organiskt avfall: bioslam, fiberslamoch matavfall. Bioslam benämns ofta överskottslam och är mikrobiellt slam från biologiskvattenrening. Fiberslam kan definieras som slam från massaindustrin med en hög halt avlignocellulosa. Med matavfall menas allmänt de oönskade delarna av maten från hushåll,storkök och matindustrier.Tre primära avfallshanteringsscenarier, ett scenario för varje typ av avfall, som inkluderadeförbehandling och rötning simulerades varav ett var ”bioslamscenario” medultraljudsförbehandling, ett ”fiberslamsscenario” med förbehandling med termisk hydrolysoch ett ”matavfallsscenario” med förbehandling med skruvpress. Övriga sex scenarieruppskattades för att fungera som referenser att jämföra de tre primära scenarierna mot.De resulterande livscykelanalyserna visade att rötning av vissa organiska avfall leder tillnästan likvärdiga utsläpp av växthusgaser, försurande ämnen och gödande ämnen somförbränning av avfallet (där värmen tillvaratas). Den stora nackdelen med rötningsprocessen,är den elanvändning som krävs för förbehandling och rötning. En elanvändning som i det härfallet har antagits försedd från kolkraft, ett vanligt förekommande marginalantagande isamband med livscykelanalyser. Om rötnings- och förbehandlingsprocesserna kan drivas påmindre utsläppsintensiv elkraft är det möjligt att på det hela taget göra miljövinster eftersommetangasen från rötning med fördel ersätter fossila drivmedel.I det här projektet uppskattades miljömässig påverkan och energivinster/förluster av atthantera organiskt avfall med förbehandling och rötning. Dessa vinster och kostnader jämföresmed konventionell avfallshantering i Sverige d.v.s. förbränning av slam och sortering ochrötning efter sortering av matavfall.

A seven-step sequential extraction scheme was used to track changes in operationally defined copper speciation during the composting of a mixture of grass clippings and sawdust originating from tanalised timber. Starting materials were either unamended or treated with differing amounts of soluble copper, using a copper acetate solution, and then composted in the laboratory. Results showed that at the start of the experiment over 80% of the copper present in the unamended materials occurred in forms not immediately available for plant uptake. However, composting processes enabled the release of this copper which then, over time, became more bioavailable. Large amounts of copper in the copper amended materials were initially detectable in all fractions except the residual one, but over time it was seen to move from all fractions to the EDTA extractable fraction, thought to determine organically complexed / chelatable metals (Amir, 2005). This continued until an equilibrium was reached and then the water and calcium nitrate extractable forms appeared to hold the excess. Copper as determined by these extracts would be available for plant uptake. In the second experiment, three different organic wastes (grass/sawdust, pig slurry/sawdust and sewage sludge cake/sawdust) to which copper had been added as copper acetate, sulphate or EDTA, were composted in the laboratory. Samples were taken at 0, 105 and 318 days and subjected to a range of analyses: copper by sequential extraction using two different extraction schemes, a chelating resin membrane (CRM) procedure and by XRF spectrometry; FTIR analysis for functional groups; total carbon, nitrogen and sulphur; pH, EC, NH4+ and NO3- nitrogen, COD, germination indices and optical properties of water extracts. Sequential extractions demonstrated clear changes in copper distribution amongst various fractions within the materials, with copper originally present in the materials being transferred from the oxidisable fractions to easily extractable (and hence potentially phytoavailable) fractions. Transfer of copper from available to less available fractions in copper amended materials was also seen with movement of copper within copper EDTA treated materials being the slowest of all. Initial amounts of copper in fraction 1 extracted from all samples determined the rate at which copper was transformed. CRM determined copper correlated strongly with copper from fraction 1 of the Tessier scheme, although changes over time did not correspond well. Other parameters measured indicated that that the material was maturing (decreases in C/N and polysaccharide functional groups). However, other results demonstrated that the composts were still immature and unstable. Such slow decomposition was attributed to the high lignin content of the materials. Nevertheless, immobilisation of potentially phytotoxic level of copper was still demonstrated. The usefulness of chelating resin membrane as a predictor of phytoavailable copper is also discussed.

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Two significant pieces of legislation in California have mandated that cities and counties must reduce their waste streams. Assembly Bill 341 establishes that California must divert 75% of its waste from landfills by the year 2020. The first bill that included composting, Assembly Bill 1826, was passed in 2014 and requires that commercial users enact composting beginning in 2016. These initiatives have led cities and counties to seek ways of implementing composting programs. Using the City of Napa as a case study, this thesis argues that a composting program can be integrated into any existing waste hauling service. Although there are some challenges, including effectively reaching all residents eligible for the program and finding ways to encourage people to change waste disposal habits, other communities should be able to adopt Napa’s model. Napa’s program should act as an outline for other communities to develop similar outreach strategies, public education initiatives, and pilot programs. Once implemented, cities can continue creating a sustainable community through the use of new technologies. Not only will creating a composting program allow cities and counties to be in compliance with Assembly Bill 1826, it will also offer benefits that extend beyond the local scope, such as reducing greenhouse gas emissions.

Submitted by ANTONIO MÁRCIO SOUZA ROCHA (antoniomarcio.sr@gmail.com) on 2017-12-13T09:44:45Z No. of bitstreams: 1 Dissertação_Antonio_Márcio_Souza_Rocha.pdf: 1190191 bytes, checksum: 015bfe55661c0bd6c2afde0caba596ba (MD5) / Submitted by ANTONIO MÁRCIO SOUZA ROCHA (antoniomarcio.sr@gmail.com) on 2017-12-14T11:24:59Z No. of bitstreams: 1 Dissertação_Antonio_Márcio_Souza_Rocha.pdf: 1190191 bytes, checksum: 015bfe55661c0bd6c2afde0caba596ba (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2017-12-14T12:15:41Z (GMT) No. of bitstreams: 1 rocha_ams_me_jabo.pdf: 1190191 bytes, checksum: 015bfe55661c0bd6c2afde0caba596ba (MD5) / Made available in DSpace on 2017-12-14T12:15:41Z (GMT). No. of bitstreams: 1 rocha_ams_me_jabo.pdf: 1190191 bytes, checksum: 015bfe55661c0bd6c2afde0caba596ba (MD5) Previous issue date: 2016-07-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A presença de elementos traços no lodo de esgoto (LE) é uma das restrições quanto ao seu uso em áreas agrícolas. Nesse sentido, objetivou-se com este estudo avaliar os efeitos da aplicação do lodo, aos dezoito anos, em Latossolo Vermelho eutroférrico sobre a concentração pseudototal e disponível de Ba, Cd e Cr na profundidade de 0 - 0,2 m, bem como quantificar os mesmos metais na parte aérea de plantas de milho. O experimento foi desenvolvido em condições de campo, utilizando-se o delineamento experimental em blocos casualizados com 4 tratamentos e 5 repetições. Os tratamentos foram: 0 Mg ha-1 controle (sem lodo de esgoto e com fertilização mineral), 5; 10 e 20 Mg ha-1 de LE, base seca. Os teores pseudototais e disponíveis de Ba não foram influenciados pelas doses de LE, na profundidade de 0 - 0,2 m. A concentração média de Cd pseudototal foi aproximadamente 1,784 mg kg-1, enquanto que o teor Cr foi maior na dose de 20 Mg ha-1. Esta dose proporcionou, ainda, uma maior disponibilidade para Cd e Cr. Os teores de Ba, Cd e Cr na planta de milho não foram incrementados pelas doses de lodo de esgoto no décimo oitavo ano de aplicação. / The presence of trace elements in sewage sludge (SS) is one of the restrictions on its use in agricultural areas. In this sense, the objective of this study was to evaluate the effects of application of sewage sludge supplemented with K, at eighteen, in Haplortox on pseudototal concentration and available Ba, Cd and Cr in the depth of 0.2 m, and to quantify the same metals in the whole plant corn. The experiment was conducted under field conditions, using the experimental randomized block design with 4 treatments and 5 repetitions. The treatments were: 0 Mg ha-1 = control (without sewage sludge and mineral fertilization), 5; 10:20 Mg ha-1 of sewage sludge, dry basis. The pseudototais and available levels of Ba were not affected by LE doses at a depth of 0.2 m. The average concentration was approximately 1,784 Cd pseudototal mg kg , while the Cr content was greater in the 20 mg h-1. This dose provided also a greater willingness to Cd and Cr. The Barium, Cd and Cr in corn plant were not incremented by sewage sludge doses in the eighteenth year of application.

The thesis is about the processing of biological waste in the Czech composting plants with focus on the quality of the final compost. In 2016, there was more than 160 composting plants in the Czech Republic. The thesis is focused on the most widely used technologies in small composting plants in terms of their impact to the quality of the final product, including the follow-up of individual indicators during composting. The best technology in my work is based on a higher decomposition temperature (85 ° C) at the first stage of composting. The practical part of thesis is focused on the measurement of ion-exchange capacity according to Sandhof as a main material for the overall evaluation of the functionality of composting. The final value shows the compost quality of the individual composting plants in terms of ion exchange flexibility of the produced substrate. The best result was achieved with the combination of composting boxes and composting in the belt heaps. The value of the ion-exchange capacity with the best technology was 52.8 mval .100 g of the soil, with 77.9% of the distributed biowaste. You have to expect with an average annual costs of composting about 1,696,000 crounds in the Czech republic, when you are designing small functional composting plant with production of 2000 tons of the compost per year.