Izvorni znanstveni članak
Truck Transportation and Chipping Productivity of Whole Trees and Delimbed Energy Wood in Finland
Juha Laitila
orcid.org/0000-0003-4431-3319
; Finnish Forest Research Institute Joensuu Research Unit P.O. Box 68, FI-80101 Joensuu Finland
Kari Väätäinen
; Finnish Forest Research Institute Joensuu Research Unit P.O. Box 68, FI-80101 Joensuu Finland
Sažetak
The present study aims to evaluate the competitiveness of various supply systems of small-diameter wood harvested from young stands for fuel. Trees were harvested for the cost comparison either as (i) delimbed longwood or (ii) as whole trees or (iii) the harvesting was based on bundle-harvesting using the Fixteri II bundle harvester. The felling of whole trees and delimbed longwood was carried out using a conventional harvester head equipped with multi-tree-handling accessories. Forwarding was carried out using a standard medium-sized forwarder. The comparison of procurement costs was done at stand level as a function of breast height diameter (5-13 cm) and on-road transportation distance (5-160 km). The harvested wood was chipped either at a roadside landing or at a terminal using a trailer-mounted drum chipper. The comparison of the supply systems was done using recently published productivity parameters and data obtained from complementary field studies.
According to the cost assessment, whole-tree harvesting and chipping at the roadside landing was almost invariably the most cost-efficient supply system. The cost of whole-tree and delimbed longwood chips was at the same level when the breast height diameter of the harvested trees was 11 cm (pine) or more. The felling of whole trees is cheaper, but the cost difference diminished as a function of tree size. The productivity of forwarding, transportation and chipping of delimbed longwood was significantly higher compared to that of whole trees. When applying roadside chipping in Finnish conditions with small and sparsely located forest holdings, acquiring large enough concentrations of wood for profitable production is a great challenge. Machine relocations can be reduced by transporting raw material to terminals or the end-use facility to be chipped. However, the low bulk density of the initial material restricts the operation radius unless the wood biomass is pre-processed. According to the results of our study, harvesting of delimbed energy wood is a promising way to simplify operations and to reduce transportation and chipping costs. In the case of whole-tree bundling, savings in transportation and chipping costs did not offset the high felling and compaction costs, and the bundling system was the least competitive alternative.
Ključne riječi
whole trees; delimbed longwood; chipping; transportation; small tree harvesting; young stands; terminals
Hrčak ID:
116817
URI
Datum izdavanja:
3.9.2012.
Posjeta: 2.165 *