14 February 1997

To dry, suck dont blow

SUCK rather than blow. That is the approach with a novel in-box drying system which is giving encouraging results in PMB tests.

Outlined by designer/developer Frank Pirie at the Scottish potato event, the Aspire positive ventilation concept offers flexibility and uniform temperatures.

Box storage has gained ground fast in the past 25 years, said Mr Pirie. At least 80% of Scottish potatoes and more than half the English and Welsh crops are held that way. But current forced ventilation systems all have disadvantages, not least the need for precise box dimensions and positioning.

The Aspire method turns the blowing idea on its head, drawing air through groups of spaced boxes with retractable blinds sealing the passages between them.

"The reason it works so well is that the system resistance is constant irrespective of the size of the store," explained Mr Pirie."

The technique allows ventilation to begin with as few as 20 boxes in place.