13 November 1998

Humber grower stirs it up and saves the day…

By Andy Collings

MOST would concede that this years grain harvest has not been an easy one. Delayed, and continually interrupted by poor weather, the chances of grain entering the store with moisture contents below 15% were slim.

The result has been that in many cases driers have been working overtime, adding unwanted costs to a product already threatened by low returns. Worse, there are those with on-floor drying systems still looking at heaps of moist grain which, with the recent wet weather, resolutely fail to dry down to the required moisture content despite weeks of expensive blowing.

One farmer who believes he could have succumbed to such a predicament is Bill Kirkby who runs a 1080ha (2700-acre) arable unit at Beaumontcote, Barton on Humber, where the cropping includes 560ha (1400 acres) wheat, 120ha (300acres) of barley, 120ha (300 acres) peas and 40ha (100 acres) oilseed rape. A last-minute decision in June to install a grain stirring system into one of his key grain stores has, in his opinion, saved the day.

"We operate two Claas Lexion combines and, with our limited drying facilities, it is soon possible to have a frightening amount of wet grain on the floor," he says. "This harvest was one when we had to go with the combines when ever we could – to the extent that a lot of wheat came in at over 25% moisture."

On-floor drying at these high moisture levels, in normal circumstances, would have been a challenging operation – one fraught with the danger of hot spots, mould and general quality deterioration. So, concedes Mr Kirkby, the installation of a grain stirring system – in this case a Rekord – was a timely decision.

Fitted in an 800t store having a central tunnel to create two 400t sections, the system comprises four vertical augers which move laterally across a section as it travels on rails running the length of the store.

This arrangement means that 400t of grain can be dried either as a batch or, if preferred, kept in situ. Grain stored on the other side of the tunnel requires the auger unit to be moved across onto another set of rails – an operation which takes only a few minutes to accomplish.

"In effect, we have two 400t batch dryers which this year weve used to dry over 1600t of grain," says Mr Kirkby. "With grain stored at about 23% it took five days to reduce 400t down to under 15% as a combined stirring and blowing exercise. We used about 3.5t of heating gas during this time."

In operation, as heated air is blown in from below, the four vertical augers move across the store which is loaded to a depth of about 3.3m (10ft); auger ends are about 8cm (3in) above the floor. The design of the augers flights is such that they ensure grain is not just lifted from the lowest depths to the surface but also allows grain from other levels to be moved.

As the augers move slowly back and forward, the whole unit moves along at a rate of 1.2m (4ft) per minute. Once the end of the store is reached, it automatically works its way back to the other end – the augers taking another route so, over a period of time, all the grain is moved.

Safeguards are built into the system. If an auger should hit a tough spot, causing it to hang back, the other three automatically wait for it to work through it before continuing; other sensors keep the unit moving squarely along the guide rails.

Advantages cited by Rekord for the system include the prevention of capping and crop compaction, a reduction in static air pressure and evenness of drying.

All of which Mr Kirkby would no doubt concur with, but he found that for the system to work well there were important "extras" required – in the form of air extraction fans.

"Theres little point having an efficient drying system like this unless you can remove moist air from the store," he says. "Some mornings, after a nights drying, we would find the whole store dripping with water."

Mr Kirkby is still unsure of the actual costs involved in the drying process using the stirring system – the object this year was to keep pace with the combines in a difficult time. But he is convinced the flexibility that the system provides – to batch or to store – clearly offers some financial justification for a purchase and installation price of about £15,000.

The plan next year is to use the stir-dry system for the majority of his combinable crops, should it be necessary – bringing them in, drying and then moving them to a more permanent store.

"The only alarming thing is to see the initial, gratifying sight of a store filled to the brim with grain, reduce significantly in volume as it dries in only a matter of days – but then thats wet grain for you."

Bill Kirkby:

"A lot of grain came in at 25% moisture this year."

Batch or store…its the flexibility of the Rekord grain stirring system that appeals to Bill Kirkby.