Treatment of desalination brine using an experimental solar pond

Abstract EN

Brine from seawater desalination plants is deposed to the sea causing a negative impact on the marine life.

Solar evaporation ponds are especially suitable to dispose of reject brine from inland desalination plants in arid and semi-arid areas due to the abundance of solar energy.

Nearly all forms of salt production require evaporation of water to concentrate brine and ultimately produce salt crystals.

In this article research, an experimental shallow solar pond (SSP) having a surface area of 1*1 m2 and depth of 20 cm was built.

Solar pond using two reflector mirrors extending for five days from 12 to 16 July 2015 was tested.

Mirrors, which are movable for five different angles that makes with horizontal, were used as reflectors in order to increase the thermal energy for the surface of the solar pond during the day.

The main factors affecting the evaporation rate which are relative humidity, wind speed, ambient air temperature and solar radiation were studied.

The results showed that the little of decreasing evaporation rate was observed by increasing relative humidity and maximum evaporation rate was observed at relative humidity of 67.6%, while slight increasing of evaporation rate was observed by increasing ambient air temperature, evaporation rate appears to decrease slightly as wind speed increases and gradual increasing of evaporation rate with increasing solar radiation.

Comparisons between experimental and theoretical results have been performed which good agreement has been achieved.

Results showed that evaporation rate increases with decreasing the mirror's angle that makes with horizontal β.

It was concluded that using two mirrors are very effective more than using one mirror when they are used as reflectors and that the best performance of the evaporation can be achieved when the mirrors are employed as reflectors.

In conclusion, this system proved to be promising using two mirrors which reduced the solar pond area and hence reduced area needed for brine evaporation in Gaza strip desalination plants.

The research can be further developed to achieve better results using large scale solar pond