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EXPLOITATION OF MARGINAL FOREST RESOURCES FOR FUEL.

Objective


A considerable production of wood for energy has been established in Denmark. Poor quality plantations are clear cut and all trees are chipped whole with their branches and tops on. This new productiuon reached approximately 200000 tonnes of fuel chips annually corresponding to about 10% of the average annual conifer cutting in Denmark. Time and method studies of chipping demonstrated that row thinning which is commonly used in normal terrain, cannot be used in difficult terrain. The design of the skid road system influences the productivity of the chipper. In hilly terrain the skid roads had to be placed at right angles to the slope, so that the chipper was driving either downhill or across the slope.
The time studies of integrated harvesting revealed a number of problems and established the relative time consumption when industrial roundwood and fuel chips are produced from the same tree. The investigations demonstrated that integratedharvesting makes it possible to increase the amount of chips that it is profitable to harvest. More research is required to elucidate the potential of integrated harvesting.

A considerable production of wood for energy has been established in Denmark. Poor quality plantations are clear cut and all trees are chipped whole with their branches and tops on. This new production reached approximately 200000 tonnes of fuel chips annually corresponding to about 10% of the average annual conifer cutting in Denmark. Time and method studies of chipping demonstrated that row thinning which is commonly used in normal terrain, cannot be used in difficult terrain. The design of the skid road system influences the productivity of the chipper. In hilly terrain the skid roads had to be placed at right angles to the slope, so that the chipper was driving either downhill or across the slope.
The time studies of integrated harvesting revealed a number of problems and established the relative time consumption when industrial roundwood and fuel chips are produced from the same tree. The investigations demonstrated that integrated harvesting makes it possible to increase the amount of chips that it is profitable to harvest. More research is required to elucidate the potential of integrated harvesting.
THE EXPLOITATION OF LOGGING RESIDUES AND SMALL THINNING TREES FOR FUEL IS RAPIDLY INCREASING IN DENMARK, AND A NUMBER OF PROBLEMS ARISING FROM THIS EXPLOITATION REMAIN TO BE SOLVED. THE MOISTURE CONTENT OF FRESHLY FELLED TREES IS CLOSE TO OR EXCEEDS THE POINT WHICH IS CRITICAL FOR THE COMBUSTION IN MANY CHIP FURNACES. FOR THIS REASON IT WILL BE ESSENTIAL TO REDUCE THE MOISTURE CONTENT OF THE CHIPS AS MUCH AS IS ECONOMICALLY FEASIBLE, AND TO PREVENT ANY MOISTURE ACCUMULATION DURING STORING.
PART ONE OF THE INVESTIGATION CONSISTS IN TESTING STEAM PERMEABLE TARPAULINS AND COMPARING THEM WITH CONVENTIONAL TARPAULINS IN THE LABORATORY AND IN THE FIELD. IN THE AUTUMN OF 1986 THREE FIELD TRIALS WERE STARTED IN JUTLAND. PART TWO CONCERNS THE STORAGE AND ENERGY ECONOMY OF LARGE CHIP AND CHUNK PILES. THIS PART OF THE INVESTIGATION IS CARRIED OUT IN A COLLABORATION WITH THE SWEDISH UNIVERSITY OF AGRICULTURAL SCIENCES. IN BIRKEBAEK PLANTATION A STUDY IS MADE OF THE DRYING AND STORING OF STANDARD CHIPS AS WELL AS CHUNKWOOD RANGING FROM 7 TO 15 CM. PART THREE, CHIP-HARVESTING UNDER ADVERSE TERRAIN CONDITIONS: RESEARCH AND DEVELOPMENT WERE STARTED IN ROLD FOREST, NORTHERN JUTLAND.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

Skovteknisk Institut
Address

1875 Frederiksberg C
Denmark