Development and examination of high-performance fluidised-bed vibration drier for processing food production waste

Abstract

Drying and processing wet particulate food production waste, such as distillery dreg, brewer's grains, beet pulp, spent coffee and barley slurry etc. for their further use as cattle fodder or fuel is an important and topical problem, which needs effective solutions. As a solution of the problem, the authors have developed improved equipment and a fluidised bed vibration drier, which ensures reaching the required output of the work process and final moisture content in the waste at a minimum power and material intensity and features the combination of the high feasibility with the high reliability of design. In order to validate the improved drying work process together with the optimum parameters of the vibration drier, theoretical investigations based on the mathematical model of the process developed by the authors have been carried out. The process of the vibration drier’s frame oscillating together with the waste has been examined, which has resulted in the generation of the differential equation that analytically describes the said process. The work process under consideration has been researched into from the thermophysical point of view using the specific initial data typical for the specific food producer. The research has resulted in obtaining the following design and process parameters of the vibration drier, in particular, for its heating pipes: diameter rt = 0.1 m; length lt = 5 m; number nt = 20, heat-transfer factor Kp = 30 and the final temperature of the dried food production waste to2 = 80 °C. The listed parameters provide for reaching the required final moisture content in the dried food production waste. Also, new relations have been generated for determining the principal process parameters of the improved drier (productive capacity, heat consumption, mass of heat carrier, waste conveyance speed, sizes and masses of the drier’s actuating elements). The obtained relations can be applied in the further theoretical and experimental research on the drier as well as the development of standard methods for its design and calculation.