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Biomass Chemical Looping Gasification (BCLG) is a cost-effective and efficient alternative to conventional gasification. The selection of appropriate oxygen carriers (OCs) is crucial for stable BCLG performance. These OCs need to possess high reactivity, selectivity, material strength, and resistance to sintering. The study investigated various OC materials, including industrial wastes (copper, nickel slag, desulphurization, LD, and ladle slags), residential waste (sewage sludge ash), and natural ore (manganese). The evaluation of OCs focused on reactivity, H2-selectivity, mechanical strength and sintering behaviour. Except for ladle slag, all OC samples exhibited favourable reactivity due to the presence of Fe- and Mn-oxides possessing high oxygen transport capacity (10–17.6%). Nickel slag, manganese ore, and desulphurisation slag displayed notable H2-selectivity (8.7 to 10.4). It can be attributed to the presence of less-active (lattice) oxygen, limiting strong oxygen agents such as Fe2O3, Fe3O4, and Mn2O3. Moreover, desulphurization slag contained highly selective Ca2Fe2O5, which falls within the partial oxidation zone of the Ellingham diagram. Furthermore, all OC samples exhibited desirable material strength (>20 MPa), suitable for fluidised bed reactors. However, nickel, LD, and ladle slags demonstrated limited sintering with sintering onset temperatures exceeding 963 °C. This limited sintering may be attributed to the absence of iron silicates, iron-bearing aluminium silicates, manganese silicates, and potassium that contributed to the low thermal stability observed in the remaining OCs. Altogether, nickel slag calcined at 1100 °C was identified as the most promising OC material with optimal reactivity, selectivity, material strength, and minimal sintering for BCLG. Overall, this study provides a detailed and scientific methodology for OC selection and can aid future OC development.

Sohn International Symposium on Advanced Processing of Metals and Materials -- AUG 27-31, 2006 -- San Diego, CA, WOS: 000241814600025, Generally accepted formula related to sulfur slag-metal distribution ratio is given by the following equation: [GRAPHICS] According to the above equation it can be deduced that sulfur distribution between slag and metal is governed mainly by metal composition (f(s) term), slag composition (slag basicity and in turn sulfide capacity), oxygen potential of the system (f(s) term) and temperature (related to equilibrium constant, K). In this study, the results of ladle furnace operations conducted in Erdemir-Iron and Steel Works Co. (Turkey) in relation to sulfur removal, have been given. Typical ladle furnace slag analyses of 4937K quality steel have been presented. Activity coefficient of FetO, gamma(FetO), have been calculated with the relation obtained from the literature. Activity calculations have been performed with the program written in Mathcad. The changes in activity of FetO in the slag phase, a(FetO), have also been studied in relation to the sulfur removal: The relation between % Decrease a (FetO) and %DeS (measured) have been investigated for 4937K runs and some other types of steel produced in the Erdemir Plant. Related to ladle operations %desulfurization defined as [(%(S) under bar (initial) - %(S) under bar (final))/%(S) under bar (initial)]*100 values have been presented for different steel qualities., Minerals, Met & Mat Soc, Acad Mexicana Ciencias Mat, Amer Foundry Soc, Amer Inst Chem Engineers, APMI Int, ASM Int, Asociac Argentina Mat, Assoc Iron & Steel Technol, Assoc Italiana Met, Australasian Inst Min & Met, Austrian Soc Met & Mat, Beijing Gen Res Inst Min & Met, Benelux Met, Brazilian Assoc Mat & Met, Brunei Darussalam Inst Chem, Ceram Soc Japan, Chem Soc Japan, Chem Soc Pakistan, Chem Soc Peru, Chilean Chem Soc, Chinese Soc Met, Cobalt Dev Inst, Colegio Ingenieros Chile, CSIRO, Czech Soc New Mat & Technologies, Danish Ceram Soc, Danish Chem Soc, Danish Met Soc, Electrochem Soc, Electrochem Soc Japan, Engn Conf Int, Eurometaux, European Ceram Soc, Federat European Mat Soc, Georgian Ceram Soc, German Soc Min, Met, Resource & Environm Technol, Gintsvetmet Inst, Gipronickel Inst, JS, Hellen Ceram Soc, Indian Inst Met, Inst Nonferrous & Rare Met, Inst Mat Engn Australasian, Inst Mat, Minerals & Min, Inst Met & Technol, Inst NonFerrous Met, Inst Argentino Siderurgia, Integrated Chemists Philippines, Int Aluminium Inst, Int Energy Fdn, Int Lead Zinc Res Org Inc, Iron & Steel Inst Japan, Israel Chem Soc, Japan Inst Met, Jordanian Chem Soc, Korean Acad Sci & Technol, Korean Chem Soc, Korean Inst Chem Engineers, Korean Inst Met & Mat, Malaysian Inst Chem, Mat Res Soc, Mat Soc Portugal, Met Sco CIM, Min Engn Int, Min & Mat Proc Inst Japan, Nonferrous Met Soc China, N Amer Thermal Anal Soc, Polish Assoc Met Engineers & Technicians, Portugese Chem Soc, Slovak Met Soc, Slovenian Ceram Soc, Slovenian Soc Mat, Soc Francaise Chimie, Soc Francaise Met & Mat, Soc Royal Chimie, Soc Min, Met & Explorat, Soc Chem Engn Japan, S African Inst Min & Met, Swedish Soc Mat Technol, Swedish Steel Producers Assoc, Technol Inst VZW, Amer Ceram Soc, Chem Soc Thailand, Finnish Assoc Min & Met Engineers, Canadian Min Journal, Ferrous Met Journal, Ind Minerals, Journal Tech Elect Mat, Magnesium Monthly Review, Mat Engn News, Mineral & Met Proc, Mineral Proc Journal, Min Journal, Nonferrous Met Journal, Ore & Met Publishing House, European Journal Min Proc & Environm Protect, Ausmelt, FLOGEN Technologies Inc, Korea Inst Geosci & Mineral Resources, Korea Zinc Co Ltd, LS Nikko Copper, Outokumpu Technol, Posco, Umicore Precious Met Refining, Xstrata Technol