Recommendations for Management of Large Scale Storage of Wood Prunings to Avoid Quality Changes

Permanent crop prunings are recognised as a potential source of biomass in Europe with a reduced degree of exploitation. EuroPruning project aims to provide technical solutions to make pruning products a reality in the solid biofuel market. The project tackles the variations of the quality along the whole supply chain. To provide guidelines to stakeholders willing to create logistic chains on prunings, the EuroPruning study has assessed quality changes of pruning residues during storage since it is the stage in which the quality is likely to suffer the highest degradation. Outdoor storage tests have been carried out during 6 months in three different European areas (representing three climate conditions) of high density of permanent crops. Experimental large scale chip piles and bale stacks have been built for that purpose from different species and net energy variation after storage has been assessed. Risks of auto-combustion and occupational health hazards linked to inhalation of air-borne spores released during material handling have also been part of the investigation. The results showed a positive energy variation in the material stored in the bale stacks contrary to most of the tests made with comminuted material. Some general recommendations to improve storage of prunings are also presented in this paper.
Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 580-586