The reduction in total energy demand in modern european maltings
New maltings in Europe have been designed which can show savings in capital costs and energy requirements. The Clova system employs a circular vessel with a moving floor and can be constructed in steel or concrete. Batches of up to 400 tons of barley can be steeped, germinated and kilned in the one vessel. The revolving floor enables all the turning and loading machinery to be in fixed position. The central air duct reduces the distance the air has to travel and the space below the floor can be greatly reduced so keeping the steep water volume to a minimum. Completion of kilning within a 24 h period requires up to 4 times as much power as a longer cycle but the lower construction costs and better preservation of heat-labile enzymes balance this disadvantage. The design is well suited for modern steeping techniques. Experiments in the author's own company to reduce water usage comprise adding only sufficient water to a revolving drum to bring moisture content to the required level. No effluent is produced and the malt is of good quality but has a high bacterial count and gives a sharp flavour to the beer unless the husk is removed. Presumably due to phenolic compounds normally leached out during steeping. Methods for reducing the amount of electricity used in malting and for recovering and using waste heat are discussed. These include vapour phase recovery of kiln exhaust, the use of a diesel/gas engine in place of an electric motor for kiln fan drive and recovery of heat from refrigeration plant.
Keywords: air economics energy equipment heat exchange malting pump