Design And Experimental Operation Of A Times Two Liquid Desiccant Regeneration System PDF Download

This work presents an experimental study of the performance of a small-size solar-powered liquid desiccant system (LDS) that meets both space air conditioning and fresh water needs in Beirut humid climate. The experimental station is setup such that it can provide space comfort through the use of the system dry air stream out of the dehumidifier and fresh water needs through the capture of water condensate from the humid air leaving the regenerator. The experimental station was instrumented to facilitate the measurements of temperature and humidity content of air and liquid desiccant streams, the amount of collected water condensate, the regeneration heat, and the energy consumed by the fans. The system performance was assessed using published correlations and based on retrieved amounts of distilled water for different regeneration temperatures, ambient conditions, and air flow rates at liquid desiccant temperature of 20 oC entering the dehumidifier. Results have shown that during the month of April the water collection rate reached 3.21 liter/hour at ambient temperature of 24.5°C and regeneration temperature of 80°C while during the month of August, the water collection rate was 2.3 liter/hr at the same regeneration temperature but at a desiccant temperature of 28 °C and at ambient temperature of 30 degreesC. The dehumidified air stream temperature in both cases was less than 28.4 oC and can be used for space air conditioning. Lowering the desiccant temperature to the dehumidifier from 28 to 26°C, results in outlet air temperature of 27°C. The energy consumption of the LDS system was compared with the conventional system and has shown that it is cost effective where the operational cost is less than one third of the energy used by conventional system.