Prof. Ajay Chandak and Dr. Sunil K. Somani have published a paper that describes how they've designed a multi stage evaporation system and integrated it with Scheffler Solar concentrators so as to double the output of food processing applications.

Design of multistage evaporators for integrating with Scheffler Solar concentrators for food processing applications

Abstract

Authors designed and experimented with multistage evaporation system for production of distilled water. Two Scheffler concentrators of 16 sqm each were used for generating steam in the first stage at 8 bar pressure and the pressure is gradually brought down to 1 bar, in four stage distillation unit. Total yield obtained in the project was 2.4 times that of single stage distillation. Temperature drop in every subsequent stage was designed to 25 degree centigrade. Heat of condensation in the last stage was dissipated in a solar dryer to enhance its performance. In further testing this heat of condensation in the last stage and also sensible heat of the condensate in all the stages was used for preheating of water in the next batch. The system has great potential in food processing industry for applications of juice thickening, sauces, jams, salt concentrating systems and distilled water applications. Results of the project are very encouraging.

Read the full paper.