| Title |
Design and Evaluation of Multiple Effect Evaporator Systems According to the Steam Ejector Position |
| Authors |
Deukwon Kim ; Sangmin Choi |
| DOI |
http://dx.doi.org/10.6110/KJACR.2016.28.11.434 |
| Keywords |
다중효용증발기 ; 열 증기 재압축 ; 증기이젝터 ; 증기이용율 Multiple effect evaporator ; TVR(Thermal Vapor Recompression) ; Steam ejector ; Steam economy |
| Abstract |
The evaporation of water from an aqueous solution is widely used in the food, desalination, pulp, and chemical industries. Usually, a large amount of energy is consumed in the evaporation process to boil off water due to atmospheric pressure. As a way of improving the energy efficiency of the evaporation process, the combination of multiple effect evaporation and thermal vapor recompression has been proposed and has become a successful technique. In this study, 4 multiple-effect falling film type evaporators for sugar solution are designed and the energy efficiency of the system is analyzed in response to the selection of the steam ejector position. Energy efficiency is increased and vapor is more compressed in the steam ejector as the Thermal Vapor Recompression (TVR) is arranged in the rear part of the evaporator system. A simplified 0-dimensional evaporator model is developed using non-linear equations derived from mass balances, energy balances, and heat transfer equations. Steam economy is calculated to compare the evaporation performance of the 4 proposed evaporators. The entrainment ratio, compression ratio, and expansion ratio are computed to check the ejector performance. |