Electric energy generation and technical–economic viability of a biodigester in the hospital sector

Abstract

RESUMO.A construção de hospitais se transformou e evoluiu sensivelmente nas últimas décadas, sendo visto como um processo industrializado, com aumento em escala, o que gera grandes quantidades de resíduos, causando grandes problemas ambientais. Dentro deste contexto, faz-se necessária uma nova disposição para os resíduos produzidos (biomassa) e sua reutilização. Seguindo técnicas apropriadas, surge como opção o uso do biodigestor, o qual permite que os resíduos hospitalares sejam tratados podendo gerar energia elétrica e/ou gás natural através do biogás e, ainda, possibilitam o emprego do efluente residual como fertilizante de solo. O presente estudo teve como objetivo avaliar o potencial de geração de energia e a viabilidade econômica e ambiental da adoção de um biodigestor no Hospital Geral do Estado de Alagoas (HGE). Para tal realizou-se um levantamento da biomassa residual produzida no HGE, do consumo, dos custos e da oscilação da potência elétrica e utilizaram-se equações para a obtenção dos valores de produção energética, a viabilidade econômica e ambiental. Os resultados obtidos mostraram que o hospital gera 20.914,40 kg/ano-1 de resíduos alimentares, com o potencial de geração de 840 m3/ano-1 de biogás, uma produção de energia elétrica de 5.352 kWh/ano-1. Isso resulta em um custo do equipamento que foi de R$ 80.598,00. Do ponto de vista econômico, a adoção do biodigestor no HGE não se mostrou viável, visto que a energia elétrica gerada por este sistema apresentaria o custo de R$/KWh 1,45, enquanto que o valor pago a Eletrobrás é de R$/KWh 0,24. Palavras chave: Biogás, eletricidade, hospitalElectric energy generation and technical -economic viability of a biodigester in the hospital sector ABSTRACT. The construction of hospitals has transformed and evolved sensibly in the last decades, being seen as an industrialized process, with increase in scale, which generates large amounts of waste, causing great environmental problems. Within this context, a new provision is needed for the waste produced (biomass) and its reuse. Following the appropriate techniques, the use of the biodigester, which allows hospital waste to be treated, can generate electricity and/or natural gas through the biogas and allows the use of the residual effluent as a soil fertilizer. The present study aimed to evaluate the potential of energy generation and the economic and environmental viability of the adoption of a biodigester at the General Hospital of the State of Alagoas (HGE). For this, a study of the residual biomass produced in the HGE, consumption, and costs, electric power oscillation was carried out, and equations were used to obtain the valuesof energy production,

Food and food‐related waste management strategies in hospital food services: A systematic review

“…Three of four peer‐reviewed documents had lower methodological quality, meeting one or two out of five MMAT quality criteria 39–41 . The remaining study met three out of five criteria, indicating higher quality 42 (Table 2).…”

“…One grey literature 53 record reported the largest amount saved (AUD 50000/year) from reduced hauling fees, while another 64 reported the smallest saving, (AUD 383/month) achieved by removing a rented dumpster that was no longer needed. Several records ( n = 10) 39,43,56,57,59,61,65,67–69 also reported the costs of setting up or implementing a food or food‐related waste management strategy. The largest cost (AUD 260538) was for setting up dehydrators 67 and the smallest cost (AUD 1243/year) was for food waste collection by a composting company 56…”

Economic viability of a canadian biodigester for power generation in dairy farming

“…The area for biodigester implementation must be considered despite having a low percentage (10.36%) compared to the machinery group, as if it is not used for this purpose, it could be used for another productive activity. Amounts and percentages invested in biodigester implantation could not be compared with the few studies found in the literature (Lima & Miranda, 2014;Nascimento et al, 2017;Westrup et al, 2015) since these did not detail the investment division. Moreover, most of the studies did not adopt a solid separator machine, which features a different production system with lower investments.…”

“…Due to the importance of the power generation sector, several researchers have assessed the economic viability of alternative sources. Among these initiatives are studies on the production of microalgae for power production (Holanda & Ramos, 2011); use of biogas in pig farms (Lima & Miranda, 2014;Martins & Oliveira, 2011;Westrup et al, 2015); potential and economic/ environmental viability of biodigesters in a hospital environment (Nascimento, Maia, Silva, & Santos, 2017); use of tidal power (Bispo et al, 2016); power production costs using biogas from manures of goat, cattle, and pig in semi-confinement systems (Calza, Lima, Nogueira, Siqueira, & Santos, 2015); the economic viability of biogas from pig farming for power generation (Cervi, Esperancini, & Bueno, 2010); biodigestion and biogas production using bovine manure (Dotto & Wolff, 2012); anaerobic biodigestion economic analysis in beef cattle farming (Montoro, Santos, & Lucas, 2013); and anaerobic biodigestion in pig farming (Rizzoni, Tobias, Bianchi, & Garcia, 2012). However, only one study on the viability of generating power using biogas on dairy farming has been found (Coldebella, 2006).…”

Biogas production from organic waste generated at the Hospital of Clinics: A preliminary study

“…con características en la concentración de la materia prima (tabla 1). El trabajo fue realizado tomando como referencia el estudio realizado por Do Nascimento y colaboradores, en el que analizó la generación de energía eléctrica y viabilidad técnico-económica de un biodigestor en el sector hospitalario (10).…”