Implementing by-product management into the Life Cycle Assessment of the mussel sector

Abstract

In Galicia (NW Spain), the mussel sector is an economic and social cornerstone, with great relevance at both regional and international scales. The environmental impact of this sector has been recently discussed from a Life Cycle Assessment (LCA) perspective. In previous studies, it was concluded that the management of mussel shells and mussel organic by-products needed to be implemented into future life cycle assessments. In this article, LCA methodology was used in order to assess the environmental performance of two valorization alternatives for mussel by-products: mussel shell valorization to produce calcium carbonate, and mussel organic remains valorization to produce pâté. From the environmental characterization for mussel shell valorization, propane and electricity production, sludge and ash management, haulage and atmospheric releases were identified as the hot-spots on which improvement potentials should be focused. Furthermore, the environmental profile for mussel shell valorization was compared to those for incineration and landfilling as alternative management options. The environmental characterization of pâté production from mussel organic by-product led to the recommendation of acting on the formulation of mussel pâté, the thermal energy demand and the product transport. Additionally, this valorization alternative was compared to another common scenario which considered the use of mussel organic by-product to manufacture fish meal. Finally, the valorization of mussel shells and organic by-products was implemented into the assessment of the Galician mussel sector. Thus, mussel by-product management was found to contribute to the potential environmental impacts to a lesser extent than mussel culture, purification and canning transformation.