Simulation of Countercurrent Multi-Effect Drying System

Hong Li, Lianying Wu, Xianli Wu, Yangdong Hu

Department of Chemical Engineering, Ocean University of China, Qingdao 266000, China.

DOI: 10.4236/ampc.2012.24B053                

Abstract

The paper bulids a countercurrent multi-effect drying process model which can be expressed as a linear programming(LP) problem with the minimum total energy consumption as target function. Based on the model it can be conventient to solve the heat load , degree of drying and other drying parameters of each effect. And it realizes the mathematical simulation an analysis of multi-effect drying process. Such process not only reuses the secondary steam but also utilizes the high energy grade. Drying silica sand using 1-effect drying to 5-effect drying is presented as an example. The energy consumption and energy saving rate are compared by using co-current multi-effect drying and countercurrent multi-effect drying. As a summary, the countercurrent multi-effect drying is better than co-current drying. Considered the equipment investment and energy conservation, the study also concluded that the countercurrent 4-effect drying is the optimum selection, and it can save 57.6% energy compared to countercurrent 1-effect drying.

Keywords

Countercurrent Drying; Multi-Effect Drying; Secondary Steam; LP

Conflicts of Interest

The authors declare no conflicts of interest.

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