ZEOWINE characteristics

Following the UE laws, the Italian waste management legislations is built on the "4R principle": Reduction, Reuse, Recycling and, in the end, material and energy Recovery according to the "Decreto Ronchi" D.Lgs. n. 22/1997. In addition, the Waste Framework Directive (WFD, 2008) introduced another important goal to be achieved within 2020 by member states, stating that at least 50% of waste generated has to be reused or recycled. Composting is defined (FAO Term Portal, FAOTERM) as the mixture of organic matter digested aerobically that is used to improve soil structure and provide nutrients. The composting process includes several phases that must be met to obtain quality compost. The vast majority of organic materials are compostable, including organic wastes from viticulture activities. Compost contains available nutrients of slow release and a high content of organic matter. The use of natural zeolite during the process of winery wastes composting was aimed at improving the quality of compost in terms of chemical-nutritional, biological and physical properties. The 11 January 2019 the field demonstration experiments of composting of winery wastes and zeolite were organized at CMM premise. The wastes from vine prunings and wine processing (stalks and grape pomace) were collected (total amount of 19,5 tons) and shredded (4-5 cm). The zeolite was almost 85% clinoptilolite with a granulometry 0.2-2.5 mm. Three piles of about 9 tons each were set up, the piles proportion was 1 zeolite : 2.5 wastes w/w (ZEOWINE 1:2.5). The piles were prepared by mixing the two components (Zeolite and winery wastes) with mechanical mixing equipment. Taking into account the economic, commercial and agronomical aspects related to ZEOWINE marketing, the hypothesis of composting with a lower concentration of zeolite was analyzed. In view of this, an additional pile prepared by mixing zeolite and winery wastes at the ratio 1:10 w/w (ZEOWINE 1:10) was set up. Finally, one pile without zeolite was used as a control; this was to obtain more scientific evidences on the impact of zeolite concentrations on the ZEOWINE quality. Periodical turning of each pile in order to promote aeration was carried out at least once a month, until the end of the composting process. Irrigation, in order to optimize water level by sprinklers on top of each pile, was aimed at moisture increase to 50% and maintenance. Temperature and humidity were monitored every day until the end of the thermophilic phase, successively every week. A cover system of each pile was predisposed. At the end of composting process (22 June 2019), the obtained winery wastes and zeolite-based composts (ZEOWINE 1:2.5, ZEOWINE 1:10) were compared to the Italian legislation for growth substrates and fertilizers (Legislative Decree 75/2010).