The proposed project is to develop a solution to a problem currently faced by the Mate tea industry in Brazil, namely high levels of PAHs in the final product due to current processing methods. The major issue is the direct contact between the smoke and the tea leaves during the drying process, resulting in high levels of carcinogenic PAHs. An optimum solution for the industry would be one that facilitates the continued use of Biomass as the fuel source but that ensures the production of clean, hot air for drying that is guaranteed to be free of the products of combustion from biomass combustion. There is currently no conventionally available equipment capable of achieving this and hence an innovative solution is required. Heat pipe heat exchangers have the ability to guarantee zero cross contamination between the primary and secondary gases and hence offer a potential solution but have yet to be utilised in this application. The technology has however been proven in other industry sectors and this project will carry out significant adaption and development to provide a suitable solution for the Mate tea industry.