Drying of Fibrous Crops Using Geothermal Steam and Hot Water at the Taupo Lucerne Company

Abstract

Taupo Lucerne Limited (NZ) uses geothermal steam and hot water as the heat source for the drying of lucerne (alfalfa) into .De-Hi., produced from the fibrous part of the plant, and .LPC. (lucerne protein concentrate) which is a high protein product produced from extracted juice. What was originally a pilot plant operation has been developed into full scale production plant producing approximately tonnes per annum of dried product for the New Zealand and Australian markets. Dried timber is also produced on the site in a separate operation. Drying methods used for each of the products produced at the plant are described. This paper also includes a description of recent modifications to the plant heat exchanger coils, to allow the use of high pressure separated hot water from the Ohaaki geothermal power station, rather than the saturated steam supply previously used. Possibilities for future improvements and expansion of the timber drying operation are discussed.