Search for dissertations about: "ASH FORMATION"

Showing result 1 - 5 of 96 swedish dissertations containing the words ASH FORMATION.

  2. 1. Fuel conversion and ash formation interactions : a thermochemical study on lignocellulosic biomass

    Author : Anna Strandberg; Markus Broström; Rainer Backman; Christoffer Boman; Maria Zevenhoven; Umeå universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Char conversion; pyrolysis; devolatilization; ash transformation; biomass; fuel characterization; fuel composition; ash composition; silicate formation; carbonate formation; thermogravimetric analysis; micro-tomography;

    Abstract : Biomass is considered to be CO2 neutral, and to be able to reduce the dependency on fossil fuels the need for expanded and sustainable biomass feedstock is increasing. Ash-related problems are some of the most important aspects of this increasing use of new biomass assortments in thermal energy conversion systems. READ MORE

  4. 2. Chemical Properties of FBC Ashes

    Author : Britt-Marie Steenari; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; straw ash; environmental impact of ash handling; sintering; deposits; fouling; wood ash recycling; FBC; ash leaching; ash chemistry; PFBC; forest fertiliser; ash hydration reactions; fuel additives; wood ash characteristics; CaS; ash melting; plant nutrient recycling;

    Abstract : In this thesis several aspects of ash chemistry are discussed. An issue of primary concern for boiler operators is the formation of ash deposits. New biomass fuels are introduced, many of which have unfavourable ash melting behaviour due to high levels of alkali metal species and chlorine. READ MORE

  5. 3. Formation and degradation of PCDD/F in waste incineration ashes

    Author : Lisa Lundin; Stellan Marklund; Mats Tysklind; James Mulholland; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MSW; fly ash; remediation; ash; PCDD; PCDF; formation; degradation; destruction; dechlorination; thermal treatment; Environmental chemistry; Miljökemi;

    Abstract : The disposal of combustible wastes by incineration is a controversial issue that is strongly debated by both scientists and environmental activists due to the resulting emissions of noxious compounds, including (inter alia) polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), heavy metals and acid gases like sulfur dioxide. Currently available air pollution control devices are capable of effectively cleaning flue gases, and PCDD/F emissions to air from modern municipal solid waste (MSW) incinerators are low. READ MORE

  6. 4. The relationship between fly ash chemistry and the thermal formation of polychlorinated pollutants during waste incineration

    Author : Duong Ngoc Chau Phan; Stellan Marklund; Bogdan Dlugogorski; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Incinerations; dioxins; PCDD Fs; PCBs; PCNs; flue gas; fly ash; sampling; particle characterization; XPS; XRD; SEM EDX; formation; chlorination; PCA; OPLS; OPLS-DA;

    Abstract : The thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) is a major problem in waste incineration. Ideally, rather than relying on air cleaning systems and treatment techniques, their formation should be minimized or, if possible eliminated. READ MORE

  7. 5. Ash chemistry and fuel design focusing on combustion of phosphorus-rich biomass

    Author : Nils Skoglund; Dan Boström; Rainer Backman; Franz Winter; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phosphorus; biomass; combustion; ash chemistry; fuel design; ash transformation; phosphorus-rich; ash-forming elements; fuel fingerprint; ash transformation reactions; Lewis base; Lewis acid; oorganisk kemi; Inorganic Chemistry;

    Abstract : Biomass is increasingly used as a feedstock in global energy production. This may present operational challenges in energy conversion processes which are related to the inorganic content of these biomasses. As a larger variety of biomass is used the need for a basic understanding of ash transformation reactions becomes increasingly important. READ MORE