Potential of industrial wastes generated in ciudad juárez, chihuahua, mexico, as alternative fuels in a kiln

Abstract

In Ciudad Juárez, Chihuahua, Mexico, high amounts of non-hazardous solid wastes are produced mainly by the manufacturing, nut processing and wood industries. Low-cost and environmental friendly alternatives are necessary to properly manage this kind of wastes. Recyclability is not feasible due to the predominance of waste mixtures and composite residual materials. Energetic valorization of these wastes as alternative fuels is considered as a disposal alternative with both environmental and economic advantages. The objective of this study was to assess the potential of solid non-recyclable wastes produced in Ciudad Juárez, Chihuahua as alternative fuels in a kiln. First, the different categories of wastes were classified and then physically and chemically characterized based on standard methods. Biomass wastes (sawdust and nut shell) were the highest fraction regarding weight percent, followed by the wastes categorized as energetically efficient residual organic fraction (EEROF), which includes mixtures involving wood, carton, plastics and automotive fabrics. The lower heating values, from low to high (8869, 5895 and 3553 kcal/kg), corresponded to tires, EEROF and biomass wastes, respectively. The chlorine content among EEROF wastes, polyurethane plastic and some automotive fabrics was higher than the established limits for the cement industry, thus they were discarded. The final EEROF wastes formulation, supplemented with biomass wastes and tires, complies with the recommended values for critical parameters to be employed as alternative fuels, so these non-recyclable waste streams could be energetically valorized.