2
contaminants to determine seed recovery and straw removal efficiencies. Maximum straw
removal and seed recovery efficiencies obtained were 90 and 87% respectively. Models
were developed to predict efficiencies beyond settings used in the experiment. The
predictions showed that higher airflow rate and faster wheel rotations are required to
operate the unit at higher feed rates.
The modified chaffy seed conditioner was evaluated in terms of seed processing capacity
and seed quality (purity, 1000-seed weight, and germination). Feed rate and air velocity
through the ring jet amplifier were varied. A maximum processing capacity of 33 kg/h
clean seed was achieved at an average feed rate of 80 kg/h. Straw and large particles that
amount to an average of 66% of the unprocessed seed mass were separated. Higher feed
rates generally lowered the quality of seed, and air velocity had little effect on processing
capacity and seed quality. However, compared to unprocessed seed it was possible to
increase Irish purity and International purity by 24 and 88% respectively. Thousand seed
weight was improved by up to 36%. Germination rate of the seed was increased by 68%.
