Modelling and Control of Steam Soil Disinfestation Processes

Soil disinfestation by steam is an agricultural technique that recently has been attracting growing interest for its low ecological impact. The process represents a viable alternative to methyl bromide, which will soon be banned in many countries. However, high fuel costs render the treatment only economically feasible for high-profit cultures. In this paper, a predictive control structure is presented, aimed at reducing the fuel consumption and optimising the treatment duration. The controller is based on a multiple linear parameter varying switching dynamic model that describes the soil temperature at different depths during sheet steam disinfestation. This fairly new approach allows the construction of simple models, thus overcoming the complexity introduced by physical equations.