Effects of Wood Properties and Chipping Length on the Operational Efficiency of a 30 kW Electric Disc Chipper

The development of efficient woody biomass comminuting processes and systems is of great importance for establishing bio-refineries. Using hybrid systems, which store excess energy from a diesel engine during periods of low loading for use during peak loading times, may yield higher energy efficiency compared to direct diesel-powered comminuting systems. In order to design hybrid chippers, a series of data are required on the load variations, in order to estimate the amount of energy that needs to be stored, and the peak power required. As a consequence, a detailed knowledge of the effects of wood properties on the direct power con sumption during chipping is relevant. Therefore, the objectives of this work were to study the effects of wood properties (size and density) of pine, spruce and birch trees from early thinnings in the north of Sweden on the specific power and energy demand and time consumption of a 30 kW electric chipper while producing chips of two sizes. The study has generated models that replicate the processes, which can be used when designing efficient hybrid systems. The butt area had a significant effect on the power requirements when chipping and, along with chip length, had a significant effect on the energy requirements. Butt area and chip length also had a significant effect on the chipping productivity. There were small effects caused by the OD densities and by different species. These findings agree with previous studies and can be used for designing future hybrid chippers.

[1]  Kazuhiro Aruga,et al.  A case study on the costs and the fuel consumption of harvesting, transporting, and chipping chains for logging residues in Japan , 2006 .

[2]  W. Dale Greene,et al.  Productivity and Product Quality Measures for Chippers and Grinders on Operational Southern US Timber Harvests , 2011 .

[3]  Dominik Röser,et al.  Forest energy procurement: state of the art in Finland and Sweden , 2013 .

[4]  Natascia Magagnotti,et al.  The Effect of Raw Material, Cut Length, and Chip Discharge on the Performance of an Industrial Chipper , 2012 .

[5]  J. Nurmi.  Chunking and chipping with Sasmo HP 30 conescrew chipper. , 1986 .

[6]  L. Eliasson,et al.  Comparing the efficiency of drum and disc chippers , 2013 .

[7]  N. Hartler.  Chipper design and operation for optimum chip quality , 1986 .

[8]  K. R. Johnson,et al.  Power requirements for producing wood chips with a parallel knife chipper , 1968 .

[9]  Dominik Röser,et al.  Chipping operations and efficiency in different operational environments. , 2012 .

[10]  Eugenio Cavallo,et al.  A new comminution device for high-quality chip production , 2012 .

[11]  N. Magagnotti,et al.  Determining the impact of some wood characteristics on the performance of a mobile chipper , 2011 .

[12]  Natascia Magagnotti,et al.  The effect of chipper cut length on wood fuel processing performance , 2013 .

[13]  Sun Hui,et al.  Hydraulic/electric synergy system (HESS) design for heavy hybrid vehicles , 2010 .

[14]  Kjell Eriksson,et al.  An analytical and numerical study of some aspects of the wood chipping process , 2009 .

[15]  Raffaele Spinelli,et al.  A model to predict productivity of different chipping operations , 2013 .

[16]  Rami Abdallah,et al.  Experimental study about the effects of disc chipper settings on the distribution of wood chip size , 2011 .

[17]  J. V. Belle,et al.  A model to estimate fossil CO2 emissions during the harvesting of forest residues for energy—with an application on the case of chipping , 2006 .

[18]  Lisbeth M. Hellström,et al.  A method for experimental investigation of the wood chipping process , 2008 .

[19]  J. E. Liss.  Fractional distribution on fuel chips - machine and wood parameters influence on chip quality , 1991 .