Towards a circular economy for plastic packaging: Current practice and perspectives in the City of Oslo

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MSW for Energy Recovery - 2020-2035 Scenarios for a Large City

The generation rate, total amount and composition of Municipal Solid Waste (MSW) can be affected by many parameters such as population and economy growth, unfolding of Circular Economy, implementation of new regulations for material recycling and development of sorting and recycling technology. Such changes will also affect measures to treat/utilize the MSW as well as the handling of the residues, primarily ashes. In this work, three scenarios on the future MSW sent to energy recovery for the period 2020-2035 have been developed using detailed MSW composition data from a large Scandinavian city, namely Oslo, Norway. The amount and composition of the MSW sent to energy recovery (incineration) were estimated with consideration of boundary conditions including population growth, improvement of sorting efficiency and increase of recycling rate. This work also evaluated key properties of the MSW sent to energy recovery under different scenarios, including heating value, volatile matter and carbon content and concentration of key ash-forming elements relevant to the operation of an incinerator and ash valorisation. The results revealed that important combustion properties of MSW to incineration might be affected by increased sorting and recycling, towards lower energy and ash content with the conditions set under studied scenarios. Scenario analysis revealed that changes in the fraction of plastic has the largest effect on the carbon content and heating value of the MSW. In addition, changes in the content of ash-forming elements in the MSW were identified, which are the results of the separate collection of an ash-rich subfraction, i.e., food waste

Sintering Behaviors of Synthetic Biomass Ash

Entrained flow gasification of biomass provides the opportunity to convert low-grade biogenic feedstocks to high-grade synthetic fuels. For a top-fired entrained flow slagging biomass gasifier, the thermophysical properties of the ash and slag limit process operation and affect process energy efficiency. The biomass ash has to be molten and slag viscosity has to be in a certain range for it to flow out of the gasifier. However, direct sampling, analysis, and evaluation of slag formation and behaviors are often challenging as entrained flow biomass gasification operates at high temperatures (i.e., 1200-1500°C) continuously. One alternative is to study synthetic ash's melting and sintering behaviors at elevated temperatures, which represent the major inorganic constituents in biomass ash. For thermochemical conversion of biomass, K, Ca and Si are typically the most common ash-forming elements. In this work, the synthetic ashes were prepared by mixing model compounds K2O, CaO and SiO2 in different mole ratios, which were pressed to form pellets. The selection of mole ratios was based on thermodynamic calculations that indicate that the tested model compound mixtures melt and flow with desired viscosity at certain temperature ranges. The pressed synthetic ashes were preheated at 900 °C for 8 hours to thermally homogenize them. Then the premelted synthetic ashes were heated at 1000 and 1400 °C in a muffle furnace with a residence time of 1 and 8 hours in air to study fusion behaviors and slag formation tendency, and were cooled down to room temperature gradually after the sintering test. The sintered residues were collected and analyzed by SEM/EDX to study the interactions of the model compounds and identify chemical compositions. The results showed that the mole ratios of model compounds have recognizable impacts on the composition, formation and transformation of mineral phases in residues from sintering tests. A strong correlation was also found between the sintering intensity of the synthetic ash and the mole ratios of model compounds.publishedVersio

MSW in a Circular Economy: 2020 - 2035 Scenarios for the City of Oslo, Norway

The unfolding of Circular Economy principles will have consequences on the generation rate, amount, and composition of Municipal Solid Waste (MSW) as well as the preferred methods to treat them. In this work, four plausible scenarios on the future of MSW for the period 2020 – 2035 have been developed for the City of Oslo, Norway. The scenario's consequences on (1) MSW amounts and properties and (2) the treatment methods, i.e. Waste-to-Energy (WtE), material recycling and biogas production have been evaluated. The main results can be summarized as such: (1) the evolution of both population and consumption (i.e. waste generated per inhabitant) will have a large impact; (2) meeting EU material recovery target (65% for MSW in 2035) means that several waste fractions have to be recycled at high levels, and this will be challenging without significant logistical and/or treatment capacity changes and/or technological breakthroughs, (3) in 2 out of 4 scenarios, the biogas production capacity must be expanded with a new plant to reach the 65% recovery target, (4) a "business as usual" approach is not sufficient to reach the recovery targets, (5) the combustion properties of MSW to WtE will be affected by increasing recycling, probably towards lower energy contents and higher ash contents and (6) "what-if scenario" studies should be carried out at the city/regional level as specific constraints must be included to bring valuable information.publishedVersio

Innovative teknologier innen avansert forbrenning av avfall og biomasse – Utdypende litteraturstudie

Denne rapporten er en utvidet og utdypet etterfølger til SINTEF rapporten ”Ny teknologi innen avansert forbrenning av avfall og biomasse – Litteraturstudie” (TR A6616). Hovedmålet med denne rapporten er å gi en oversikt over samt gi kritiske kommentarer/bemerkninger til potensielle nye teknologier som kan innføres ifbm. forbrenning av avfall og biomasse for å bekjempe de mest aktuelle utfordringene utpekt i en 2007 undersøkelse av 10 aCOM medlemmer innenfor avfallsforbrenningsbransjen, utført av SINTEF. To nye teknologier ble utpekt som mest interessante: O2/N2 anriking, først og fremst, for å redusere NOx utslipp, men også for å påvirke positivt forbrenningsprosessen i sin helhet Bruk av additiver mot korrosjon (og groing) Initielle eksperimentelle forsøk er kjørt for å studere effekten av O2 og N2 anrikning på konvertering av nitrogen, svovel og klor i brenselet til NOx, SO2 og HCl. De initielle forsøkene med O2 og N2 anrikning viser tydelige effekt på konverteringen av nitrogen, svovel og klor i brenselet til NOx, SO2 og HCl. Den meget begrensete forsøksmatrisen som ble kjørt var ikke omfattende nok til å separere effekten av alle parametrene som påvirker konverteringen. For svovel og klor vil også askekjemien være av stor betydning, dvs. at svovel og klor kan bindes av ulike askekomponenter og ender opp som aerosoler, belegg eller i flyveaske eller bunnaske. Brenselsammensetningen er derfor også av stor betydning, dvs. hvor mye brenselet inneholder av de ulike elementene, og ikke minst hvor mye brenselet inneholder av askekomponenter som K, Na og Ca i forhold til S og Cl.Innovative teknologier innen avansert forbrenning av avfall og biomasse – Utdypende litteraturstudiepublishedVersio

MSW in a Circular Economy: 2020 - 2035 Scenarios for the City of Oslo, Norway

The unfolding of Circular Economy principles will have consequences on the generation rate, amount, and composition of Municipal Solid Waste (MSW) as well as the preferred methods to treat them. In this work, four plausible scenarios on the future of MSW for the period 2020 – 2035 have been developed for the City of Oslo, Norway. The scenario's consequences on (1) MSW amounts and properties and (2) the treatment methods, i.e. Waste-to-Energy (WtE), material recycling and biogas production have been evaluated. The main results can be summarized as such: (1) the evolution of both population and consumption (i.e. waste generated per inhabitant) will have a large impact; (2) meeting EU material recovery target (65% for MSW in 2035) means that several waste fractions have to be recycled at high levels, and this will be challenging without significant logistical and/or treatment capacity changes and/or technological breakthroughs, (3) in 2 out of 4 scenarios, the biogas production capacity must be expanded with a new plant to reach the 65% recovery target, (4) a "business as usual" approach is not sufficient to reach the recovery targets, (5) the combustion properties of MSW to WtE will be affected by increasing recycling, probably towards lower energy contents and higher ash contents and (6) "what-if scenario" studies should be carried out at the city/regional level as specific constraints must be included to bring valuable information

Mekanismer for korrosjon og beleggdannelse ved forbrenning av biomasse og avfall - Litteraturstudie

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Ny teknologi innen avansert forbrenning av avfall og biomasse - Litteraturstudie

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