Precast concrete storage for Northern Crop Driers

Based south east of York at the former RAF Melbourne, Northern Crop Driers has successfully utilised precast concrete storage panels from Whites Concrete to maximise silage storage for its AD plant.

Leading manufacturers of dried grass horse feeds that are virtually identical to fresh grass, Northern Crop Driers needed a clamp capable of storing 6,000 tonnes of silage in an old hangar at its Melrose Farm base. With a roof height limiting the manoeuvrability of machinery to compress the stored material, Whites Concrete were called upon to create a design that would use the space to full effect, keeping silage dry and clean whilst ensuring that load demands would meet the bulk density.
The safely stored maize, grass silage (plus some sugar beet), and slurry from sister company Melrose Pigs, provides feedstock for the 500kW AD plant.

Pam Dear from the family-owned and run business said: “Investing in an AD plant made perfect sense here because it brings everything together. With our pigs and grass drying business, we knew we could generate our own green electricity, but first we had to bring in a whole year’s worth of crop, so getting our storage facility right was crucial”.

Whites Concrete worked closely with Northern Crop Driers to initially provide two designs, including one with metalwork, but 4m concrete panels were ultimately chosen as the best solution.

Pam Dear added: “We were determined to utilise every inch of the hangar to give us 6,000 tonnes of storage, so Whites’ expertise in materials and load-bearing requirements was invaluable”.

Over a period of one month, 150No 4m high (1m wide) Whites Concrete panels were installed at the 750-acre Melrose Farm, where grass, home grown maize and supplies from neighbouring farms combine with the pig slurry to produce enough power for everything required on site, with excess sold on to the grid. L-shape Groundwall panels from Whites Concrete were considered the most suitable option so as not to create any additional load bearing onto the existing structure of the old hangar. Ideal as push-walls to resist machinery loads, extreme heights of storage and areas where heavy traffic will be working, Groundwall is hygienic, as well as far quicker and more economical than block or in-situ concrete.

Following the success of the silage clamp, Northern Crop Driers has since extended the storage facility by an additional 4,000 tonnes, installing a further 90No 3m high pre-cast concrete panels from Whites Concrete to create 10,000 tonnes of silage space for the AD plant. These extra panels are from Whites Concrete’s Rockwall range, which achieves a finished concrete strength in excess of 60N for any above or below ground construction.

“Moving into AD is a very good fit with our business model”, concluded Pam Dear. “We produce 100% natural horse feeds and bedding, and now we generate our own on-site green power, with a payback of just five to six years”.