[recovery] was the use of a horizontal airflow to transport the droplets to the canopy. This minimizes drift by keeping the droplets under the canopy (no upward movement), reduces the amount of air and the fan power needed, and allows for a better targeting by keeping the air outlet to tree distance approximately constant over the full height of the trees.”
Récupair also incorporated a spray recovery panel facing the boom on the opposite side of the trees, he said. It was supposed to function as a tunnel sprayer, recovering any excess spray material and recycling it.
“Field trials showed that spray recovery was achieved, but this was good mostly when the application volume was higher and early in the season. At lower application volumes in developed foliage, recovery was about 10 percent, less than expected,” Panneton said.
So for this sprayer, the idea of recovery panels was not implemented. “Recovery was not as good as expected, the sprayer would be more complicated, would cost more, and would be more difficult to move around,” he said. “We kept the idea of the vertical sleeves and adjusted the airflow according to our research findings.”
The ideas behind the sleeve sprayer are to reduce the amount of pesticide used by distributing it better and losing less to drift, and to save fuel by reducing the power needed to move air.
Panneton was one of several Canadian scientists to lose their positions in funding cuts this year. He will no longer be doing sprayer research, so this sprayer is an orphan—the only one of its kind unless some interested grower wants one built.
Tower sprayers and tunnel sprayers are being worked on in Europe.
Editor’s note: The story headline was shortened on August 13, 2014, removing ‘one-of-a-kind.’