Italian cow powered pellets
Whilst the benefits of co-locating pellet production with a wood processing plant seem pretty obvious, setting up a 15 000 tonne-per-annum capacity plant on a dairy farm are less self-evident. Yet that is exactly what an entrepreneurial dairy farming family in Italy has done.
Located in Marmorta di Molinella in the province of Bologna, the Agricola Antonio Farm is a dairy cattle farm owned and run by passionate dairy farmers, the Pasini family. The 477 ha farm has around 400 head of cattle of which 200 are milk cows. Apart from milk production the farm grows its own feed and fodder. Furthermore, it owns and operates two manure and silage-based BTS Italy biogas power plants, each at 1 MWe capacity supplying into the power grid under the feed-in tariff (FIT) scheme.
From digestate to wood
Built during 2013, the pelleting plant was originally designed as a manure management and valorisation project to utilize the residual heat from the second biogas plant, heat from the first plant is already used for space heating and drying forage. With a grant from the Rural Development Programme of the Emilia-Romagna region, a digestate drying and pelleting line was setup to produce organic fertilizer pellets as well as liquid fertilizer. Although successfully demonstrated, the market for organic fertilizer was lacking and the farm has sufficient acreage to utilize all the digestate from both of the biogas plants without having to upgrade it. Instead it was decided to repurpose the plant to produce wood pellets for the local market and thus Greenergy Società Agricola S.r.l. was formed.
The raw material consists of sawdust, shavings and clean woodchips sourced from local suppliers and supplied by truck to the plant on a daily basis. The material is kept under roof and a wheeled loader is used to load the feed hopper.
The only major investment in the repurposing project was on the front end with a receiving hopper, screen and a new low temperature dryer from Italian dehydration specialists Scolari – the original dryer proved unsuitable for wood. The “type T” dryer works with a system of movable conveyors and process air that can change from 45°C to 140°C. The material is transferred to intermediate storage before joining the retooled Kahl pellet line and Elocom bagging and pallatizing unit. A single operator runs the pellet plant and the production is ENplus certified.