Grain Cooling: A Case Study

During the spring of 2011 Evans and Pearce (in partnership with GW Axup Ltd) designed and supplied a crop cooling system for Albanwise Farming Ltd’s storage facility at Pocklington, East Yorkshire. GW Axup is a leading supplier of agricultural ducting solutions in the Midlands and North and Evans and Pearce has partnered with them on a number of large projects.

The customer required ventilation for a new 20,000 tonne flat grain store. They had decided against under floor ventilation due to the high cost and issues with duct maintenance. Metal pedestals and on floor laterals were dismissed due to their low tolerance to the loader bucket and high replacement cost.

Store manager Roger Jackson decided on 450mm twin wall perforated ducting as recommended by Evans and Pearce Ltd. The ducting was used to ventilate each of the five, 4000 tonne sheds. Each shed measured 46m x 25m with 4.8m high concrete walling. The ducting was supplied in food grade plastic with a 1.5mm slot so that it could be used to ventilate oilseed rape as well as cereals.

Each 4000 tonne store had 4 x 42m lengths of ducting which connected to the fans through the back wall via pre cast holes in the concrete panels. Our 4kW EV centrifugal fan units were used to provide a high volume of air to the crops. Evans and Pearce specified a 450mm blowing spigot on the fan which was designed to fit inside of the duct as it emerged from the store wall. The system resistance was checked by Evans and Pearce once the store was filled and each 4kw fan is delivering 10,500m³/hr of ambient air to the stored crop.

Roger Jackson has been very pleased with the ventilation capacity of the system to date. Stored crop temperatures had dropped below 13°C by mid-November 2011, with no sign of mites or moulds.
“Considering the higher than average Autumn temperatures we have had this year, the system has worked extremely well and we are very pleased with it” commented Roger.

The next stage for this system will be to fit a control system to automate the running times of the fans based upon a differential temperature between stored crop and ambient air. Differential controllers have been proven by the HGCA to dramatically improve the cooling capacity of low volume ventilation systems whilst also offering up to 40% saving on electricity costs.