Bi-objective optimization of multiple agro-industrial wastes supply to a cogeneration system promoting local circular bioeconomy

Abstract

[EN] This research analyses and proposes an optimization model for the supply of biomass to a combined heat and power (CHP) system with a supply of different biomasses at a local level under Mediterranean conditions. The research aims to quantitatively assess whether it is economical and environmentally beneficial to transport various types of biomasses to the CHP plant, instead of landfilling, determining the biomass required according to the availability of power generation for each biomass of agricultural and agro-industrial origin. To do this, a representative case study has been developed in the Maule Region, Chile to supply power and heat to public, private, and residential buildings. The main biomasses analyzed are olive pomace, fruit pits and vineyard pruning. The results demonstrate that the supply of residual biomass to the CHP plant avoids the emission of CO(2)e generated by final disposal. Regarding the minimization of CO(2)e emissions, pruning residues are identified as the first supply option, due to their high heating value. Regarding cost minimization, olive pomace is identified as the first option, followed by fruit pits and pruning material. Furthermore, transport is not a major contributing cost or environmental factor when biomass sources are close to the CHP system, up to a maximum supply radius of 30 km. Finally, despite seasonality of agricultural biomass supply under Mediterranean conditions, it is feasible to adequately supply a small-scale CHP plant. However, this increases the storage costs involved. Other lignocellulosic biomasses could be used to optimize costs and environmental benefits.