RESUMEN
Municipal Solid Waste Incineration (MSWI) Bottom Ash (BA) is a potential alternative adsorbent for biogas treatment due to its reactivity with hydrogen sulfide (H2S). The quality of BA depends however on the nature of the waste and the process technology of the waste incineration facility. To determine whether the origin of the BA could have an influence on its H2S elimination efficiency, comparative experimental tests were conducted in a landfill site with six bottom ashes from different MSW incinerators. Results showed that one of the BAs (A) had a much higher adsorption capacity than the rest (B-F), with 37g H2S/kg dry BA, compared to 11-16g H2S/kg dry BA for the other bottom ashes. Detailed physico-chemical analyses of the six BA were performed and complemented by principal component analysis to understand the different behaviors. BA iron content and specific surface area provided by the quench product stood out as key factors that promote the elimination of H2S.
Asunto(s)
Contaminantes Atmosféricos/análisis , Sulfuro de Hidrógeno/análisis , Incineración/métodos , Residuos Sólidos , Instalaciones de Eliminación de ResiduosRESUMEN
In this study an alternative valorization of Municipal Solid Waste Incineration (MSWI) Bottom Ash (BA) for H2S elimination from landfill biogas was evaluated. Emphasis was given to the influence of water content in biogas on H2S removal efficiency by BA. A small-scale pilot was developed and implemented in a landfill site located in France. A new biogas analyzer was used and allowed real-time continuous measurement of CH4, CO2, O2, H2S and H2O in raw and treated biogas. The H2S removal efficiency of bottom ash was evaluated for different inlet biogas humidities: from 4 to 24gwater/m3. The biogas water content was found to greatly affect bottom ash efficiency regarding H2S removal. With humid inlet biogas the H2S removal was almost 3 times higher than with a dry inlet biogas. Best removal capacity obtained was 56gH2S/kgdryBA. A humid inlet biogas allows to conserve the bottom ash moisture content for a maximum H2S retention.