Solid Waste Management of a Chemical-Looping Combustion Plant using Cu-Based Oxygen Carriers

Abstract

Waste management generated from a Chemical-Looping Combustion (CLC) plant using copper based materials is analyzed by two ways: the recovery and recycling of the used material and the disposal of the waste. A copper recovery process coupled to the CLC plant is proposed to avoid the loss of active material generated by elutriation from the system. Solid residues obtained from a 10 kWth CLC prototype operated during 100 hours with a CuO-Al 2 O 3 oxygen carrier prepared by impregnation were used as raw material in the recovery process. Recovering efficiencies of 80 % were obtained in the process, where the final products were an eluate of Cu(NO 3 ) 2 and a solid. The eluate was used for the preparation of new oxygen carriers by impregnation, which exhibited high reactivity for reduction and oxidation reactions as well as adequate physical and chemical properties to be used in a CLC plant. The proposed recovery process highly decreases the amount of natural resources (Cu and Al 2 O 3 ) employed in a CLC power plant as well as the waste generated in the process. To determine the stability of the different solid streams during deposition in a landfill, these were characterized with respect to their leaching behavior according to the European Union normative. The solid residue finally obtained in the CLC plant coupled to the recovery process (composed by Al 2 O 3 and CuAl 2 O 4 ) can be classified as a stable non-reactive hazardous waste acceptable at landfills for non-hazardous wastes.

Effect of gas composition in Chemical-Looping Combustion with copper-based oxygen carriers: Fate of sulphur

“…The results obtained during 200 h of continuous operation were very successful both regarding methane combustion efficiencies and particle behaviour (Adánez et al, 2006;de Diego et al, 2007). Finally, a waste management study from the CLC plant using Cu-based residues was also carried out (García-Labiano et al, 2007b). It was concluded that this solid residue can be classified as a stable non-reactive hazardous waste acceptable at landfills for non-hazardous wastes.…”

Progress in Chemical-Looping Combustion and Reforming technologies

“…The unique work regarding environmental aspects in the handling of materials useful for CLC processes was carried out by García-Labiano et al [136] who made a study about the solid waste management of a CLC plant using Cu-based oxygen-carriers.…”

Chemical Looping with Copper Oxide as Carrier and Coal as Fuel

“…A comprehensive study of the reaction of copper-based oxygen-carriers with syngas and methane fuels has been conducted with definitive studies on the: preparation and characterization of oxygen-carriers [9][10][11][12][13] with different substrates (Al 2 O 3 , SiO 2 , TiO 2 and yttrium stabilized zirconia); chemical kinetics of the oxidation and reduction of the oxygen-carriers at both atmospheric and elevated pressures [9,[13][14]; development of design criteria [13,15], including detailed maps for the circulation of the oxygen carrier and the weight of oxygen carrier as functions of different oxygen carrier conversions in the fuel and air reactors, and oxygen carrier reactivity; the successful operation of a 500 W t [16] and 10 kW t [17,18] CLC system of two interconnected fluidized beds; development of a detailed mechanistic model [19] of the CLC system and validation with data from the 10 kW t unit; the reclamation of copper from spent oxygen carrier [20]. These studies have shown that copper oxide based carriers have great potential because of their high reactivity and resolved questions that had been raised on attrition, agglomeration, and sulfur contamination.…”