Direct utilization of solar linear Fresnel reflector on multi-effect eccentric horizontal tubular still with falling film

The paper presents a multi-eccentric tubular desalination system heated directly by a linear Fresnel reflector (LFR) field to enhance the productivity. In this novel system, the solar radiation is sent directly into desalination unit. The configuration and working processes of the proposed design are described in details. The tube inner wall with absorbing coating were used as a receiver by placing in the cylindrical cavity to absorb concentrated solar energy and transfer it to a falling water film. To verify the performance of the system in different effects, an indoor experimental eccentric tubular still was fabricated and tested under different heating conditions from 400 to 1600 W respectively. The experimental results showed that the maximum accumulated yield of the 1st and 2nd effect are about 28.27 kg and 21.37 kg, respectively. The outdoor experimental results show that the cumulative output of the unit is about 11.35 kg, the maximum performance ratio (PR) is about 2.88 with an evacuated tube solar collector. A two-effect tubular desalination system for linear Fresnel reflector with a capacity of 63.68 kg/d was proposed according to the presented theoretical and experimental work. By taking solar linear Fresnel reflector heating mode, the cost of water production reaching about $6.16/ton. •A novel multi-eccentric tubular still for solar desalination is described.•The performance ratio of the two-effect devices can reach about 2.88.•Tubular desalination device is direct coupled with linear Fresnel reflector system.•The calculate yield of the device under linear reflector solar field can reach 63.68 kg/d.