SUGAR LOSSES IN BURNT AND GREEN CANE HARVESTING IN ARGENTINA

THE PROS and cons of green and burnt cane harvesting are of great interest to the people at the Ledesma sugar plantation in the Jujuy province of Argentina. Trials conducted by the agronomy team at Ledesma indicated the potential for a reduction in sugar losses by moving from burnt cane to green cane harvesting. Burning versus green cane harvesting is also a hot issue in the Burdekin sugar industry. A group of extension staff and farmers from the Burdekin went to Ledesma in July 2005 to help conduct a trial to gain further information and verify the results found when comparing burnt against green cane harvesting. The 2005 trial found the same trends as observed in earlier Ledesma trials. There was very little difference in the loss of sugar between burning and harvesting green. The losses were quite high for both harvesting methods: around 16%. However, the source of losses differed. Sugar loss from burnt cane harvesting was mainly due to burning, whereas losses due to harvesting green cane were from losses to trash and in-field losses through the primary extractor. Consistent between this and previous trials is the loss of sugar yield from burning cane. In previous trials, the average loss due to burning was 2.7%. In the 2005 trial, the loss due to burning was estimated at 4.7% of the potential sugar yield. As losses in the 2002 green cane harvesting trials were mainly due to primary extractor and trash, the harvesting team at Ledesma moved to reduce fan speeds from 1250 to 900 r/min. They are now looking at further reducing fan speeds and lowering their pour rate in an attempt to reduce extractor losses and EM levels when harvesting green cane. If primary extractor losses can be further reduced in green cane, then the gains in sugar yield compared to harvesting burnt cane are a significant consideration in the discussion on whether there should be more green cane harvesting at Ledesma and in the Burdekin.