Hybrid Desalination System Using Parabolic Trough Concentrator as a Heat Source

Document Type : Original Article

Authors

1 Mechanical Power Engineering Department, Faculty of Engineering, Port Said University, Port Said, Egypt,

2 Mechanical Power Engineering Department, Faculty of Engineering, Port Said University, Port said, Egypt.

3 Mechanical Power Engineering Department, Faculty of Engineering, Port Said University, Port Said, Egypt

Abstract

This paper deals with the status of the new hybrid desalination methods which need more research like thermal vapor compression and direct contact membrane distillation system. The objective of this research is to theoretically investigate the characteristics of a hybrid desalination system composed of a thermal vapor compression (TVC) and direct contact membrane distillation (DCMD) systems using parabolic trough concentrator as a heat source. The proposed hybrid system aims to recover the heat of the rejected brine from thermal vapor compression system in order to obtain the highest fresh water productivity and thermal efficiency and lowest cost of fresh water product from the system. The theoretical simulation of all the systems were developed and solved by Engineering equation solver (EES).
After the validation of all the models, the design of thermal vapor compression and direct contact membrane distillation were selected. It was concluded that the best operating conditions to run the system is at motive steam pressure of 3000 kPa and boiling temperature of 70 ℃. The dynamic behavior of the hybrid system was conducted at the selected operating conditions at different seasons of the year in order to examine the performance of the system through the year. Finally, economic study was developed for the proposed dynamic hybrid desalination system. The results showed that both of the performance ratio and water productivity enhanced by 7.3 % by adding the DCMD as a secondary desalination unit. In addition, the dynamic hybrid system efficiency reached to 75%. Also, the cost of the fresh water product by dynamic hybrid desalination system was 0.0176 $/ L.

Keywords