Advanced Energy Saving in the Evaporation System of Ammonium Sulfate Solution with Self-heat Recuperation Technology

A concept of a novel double-stage mechanical vapor recompression (MVR) evaporation system based on the principles of self-heat recuperation technology for ammonium sulfate solution processing is proposed. In the paper, the single-stage and double-stage MVR evaporation systems for ammonium sulfate solution are designed and analyzed. A parametric study is performed to investigate the effects from the emission concentration of the first stage, the evaporation temperature and the temperature difference (TD) between the condensing steam and the boiling solution on the power consumption and heat transfer. During the investigation, the initial ammonium sulfate solution with a concentration of 3% is concentrated to the saturation solution, which has a concentration of 53%. The results show that despite the satisfaction to the principle of self-heat recuperation technology for the two systems, the boiling point elevation will result in a high energy consumption for the compressor in the single-stage MVR system, while the double-stage MVR evaporation system has an obvious energy saving effect with an improved amplitude of 40%.