The biorefinery of Adriatic Sea Pilot aims to valorise the different fractions from seafood processing industries placed in Ancona To this, wet separation, enzymatic hydrolysis, chemical extraction, composting and pyrolysis are developed (Fig 1).

Mollusc waste management requires a first separation step to split shell and organic fraction e.g. adding water and then using a shredding pump before separating them by gravity). Once dried and milled, shells could be used as a soil liming agent. Due to high protein content in the organicfraction of mollusc and fish waste, instead, protein hydrolysates (FPH) are obtained through enzymatic hydrolysis carried out in a 100 L pilot  reactor, followed by centrifugation to separate the raw FPH from the solid residue (bones, not hydrolysed substrate, etc) and by evaporation to concentrate the liquid stream FPH could be used as a biostimulant for the agriculture sector or as high quality N fertiliser in combination with chitin that is previously extracted from crustacean shell. On the other hand, the solid residue could be further valorised by composting and/or
pyrolysis. Biochar addition to the composting substrate would enhance the composting performance by accelerating organic waste decomposition, reducing air pollution and GHG emission, and would create a value added product (biochar compost blend). Active composting is performed in an adiabatic cylindrical reactor (operating volume of 100 L) with forced aeration Maturation phase follows in a static reactor with manual turning and final sieving is performed to recycle bulking agent and obtain final mature biochar compost composite.

Fig 1: Biorefininery scheme
Fig 2: Shredding (a), composting (b) and hydrolysis (c) reactor

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Authors: Università Politecnica delle Marche
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