Flail debarker salvages drought-damaged wattle
Sappi has imported a Morbark 5500 flail debarker from the United States, and is currently using it to debark drought-damaged wattle in the Highflats area. It's the first machine of its kind in the country, although it's not brand new technology.
|The Morbark 5500 flail debarker at Highflats.|
|The harvesting system – feller buncher and skidder.|
|The Morbark in action.|
Around 3 300 ha of drought-damaged trees, mainly wattle, in the Highflats area, posed a problem for Sappi. Debarking the timber by hand would not be viable, so it looked likely that the timber would have to be written off.
However, a solution was found in a Morbark triple-drum flail debarker, which was subsequently purchased by Sappi and brought in to Highflats, where the machine has been working for the past three months.
The wattle is clearfelled using a John Deere feller buncher, and skidded to the Morbark stationed at the edge of the compartment. The timber is fed into the Morbark which delimbs and debarks it. The stems are then run through a processor which cross-cuts and stacks the timber.
The process creates a number of opportunities, and the Sappi team is considering its options. The quality of the bark, which is mixed up with sticks and debris, is poor and unsuitable for sale to the bark factories. Sappi's Andie Immelman said they are investigating the possibility of utilising it as biofuel at the Saiccor mill at Umkomaas. However, he said that the silviculture guys are concerned about the long term impact on the fertility of the soil if all the material is removed from the site.
The tops are also a useful resource, and will be made available to the local community for use as firewood or for charcoal manufacturing,
As a result of this operation, Sappi has been able to salvage more than half of the timber.
Andie said that the company was very pleased with the Morbark's productivity, though the operating team is still on a learning curve. The machine will make it possible for Sappi to debark wattle through the winter months when the bark is very difficult to strip by hand.
Published in October 2011