Energy and environmental assessment of pellets produced from solid residues of the winery industry

Abstract

The study assessed the potential of waste by-products from the Cypriot winery industry as raw material for solid biofuels. Two different biomass blends were pelletized and assessed as an energy source for domestic hot water boilers. The samples were composed of Grape Pomace (P1) and Grape Pomace & Vine Shoots Blends (P2) provided by a Cyprus winery: Aes Ambelis (Nicosia, 35°01'12.4"N 33°09'19.5"E). The raw material was dried and pelletized at the facilities of the Agricultural Research Institute (ARI), Cyprus. The pellets were analyzed for moisture and ash content using well-established standardized methods at the Sustainable Solid Fuels Lab of Frederick University, Cyprus. Combustion tests with the pellets were also carried out at the Boilers Lab of Frederick University. The measurement campaign focused on flue gas analysis – in particular carbon monoxide, carbon dioxide, oxygen, lambda – as well as water temperature and boiler efficiency. The results obtained from analysis of the samples showed that most of the examined pellets satisfied the minimum requirements of EN ISO 17225-2 and EN ISO 17225-6 standards for woody and non-woody pellets respectively. Ash content and moisture content for both samples also complied with the standards. The results of the measurement campaign were in good agreement with results delivered by other studies conducted for similar biomass raw material. Study results showed that grape pomace and grape pomace vine shoots blend could potentially be used as an energy source for producing heat which could be exploited for the domestic and industrial sectors. Harvesting this waste stream for energy production purposes could offer economically and environmentally smart solutions for the winery industry in Cyprus, satisfying the circular economy principles which are currently at the forefront of European environmental policy.