The site at Rothes had been processing by-products from the Speyside whisky industry for over 100 years, and since 1970, handled key co-products of distilling, draff and pot ale, to produce a finished nutritional animal feeds product – Distillers Dark Grains.
However, 2013 saw the completion of a major project by Helius CoRDe Ltd , a Joint Venture created by Helius Energy Plc and CoRD (now Rothes CoRDe Ltd) to develop, build, own and operate a biomass combined heat and power plant at the facility, which includes an 8.32 MWe power plant and a 66.5t/h pot ale evaporator plant. The draff, supplemented by wood chip is now used as fuel to produce renewable energy, and liquid animal feed (Pot Ale Syrup) is produced from the pot ale.
A key requirement in the development of this new £60M facility was to enhance the treatment capacity and capability of the existing effluent treatment plant, in order to safeguard compliance with licence conditions for discharge to the iconic River Spey.
The Overall Objective
The additional treatment capacity was needed due to the larger CoRDe facility generating more condensate water, and the requirement to treat mixed distillery effluent from an additional 2 distilleries, increasing the number of distilleries treating their effluent at the facility to 9. The existing treatment facility was susceptible to loss of performance during certain times of the year, and in particular, the stage two bio-towers needed protection from excessive solids loading.
The CoRDe facility is quite unique in that it provides full biological treatment of effluent from so many distilleries, and therefore an effective solution was required to safeguard the treatment facility for all interested parties.
Having utilised DAF technology to enhance the performance of existing treatment assets at several distilleries, Siltbuster’s largest DAF unit, the D100 was specified, with feed pumps, sludge pumps, chemical dosing equipment and all associated pipework also supplied. This treatment stage protected the downstream treatment stages from excessive solids loading, allowing them to function more efficiently. Also, there was flexibility to use chemical pre-treatment as and when prevailing conditions called for additional levels of performance from the DAF.
This project again served as an excellent example of our philosophy of utilising DAF technology to enhance the treatment capacity of existing assets, with the confidence that it also has a key part to play in modern treatment facilities, should additional investment take place in the plant in future.
Frank Burns, Managing Director of Rothes CoRDe Ltd said, “The technical solution offered by SPS provided the additional capacity and capability required within the footprint of our existing plant and complemented our existing biological treatment. Installation and commissioning was delivered without interrupting our concurrent construction or processing activities. We are very pleased with the results and service.”