Modelling and operation of industrial vibrocooling units.

Abstract

[EN]Product quality is paramount for companies to maintain the trust from their customers. Powder products and in particular fertilizers can suffer damage during storage if the temperature and moisture are not appropriate. Most of the work has focused on drying, but the last stage of cooling is responsible for avoiding product out of specification. A first principles model has been developed for industrial fluidized vibrating cooling units following a multiscale approach, from the particle to the entire unit, to evaluate their operation. The unit consists of two sections using atmospheric and cool air, respectively. A refrigeration cycle is also modelled to compute the needs to cool the air. The unit’s model only includes two adjustable parameters, the heat transfer efficiency from the particle to the air as well as for the losses from the unit to atmosphere. The model has been validated using industrial data, resulting in heat flow efficiency from the particle equal to 0.30 and the flow of losses of 1.17 kW/K. The model can reproduce the industrial data within reasonable error and allows predicting the cooling cycle needs and estimating the cost of its operation as a function of the weather. The location of the facility results in the fact that during June-August the atmospheric air cannot cool the product below the critical temperature and the refrigeration cycle needs to operate.