Spray drying is used to remove moisture and turn the product into a powder for storage or convenience. It is also used for micro encapsulation to give controlled release and other functions. In the usual open cycle configuration, spray dryers vent extracted water vapour directly to the open air, often with odours and particles, creating air pollution in the locality. Closed cycle spray dryers are operated in specialist applications but a general, low cost closed cycle spray drying technology is not in use. This project will develop a closed cycle spray dryer and demonstrate it in general drying and micro encapsulation applications. Novel technologies for dehumidification, heat recovery and removal of volatiles will be investigated to meet the objective of a low cost process, to replace existing open cycle spray dryers. This will have important benefits for Sees and larger end users in terms of reduced emissions, giving greater flexibility in the sitting of their operations.