In recent years growing attention has been paid to the problem of brine disposal due to the raisingawareness of significant environmental issues related to the use of desalination processes forfresh water production. This is particularly relevant when desalination units are located in remotesites, characterised by major complexity in the construction and management of intake and outfallstructures. In the present work a novel device, named brine evaporative cooler/concentrator (BECC,patent pending), has been developed for coupling with small-scale thermal desalination plants inorder to reduce the problem of brine disposal. Such device fulfils two different functions: i) coolingof the recirculating brine (which is often mixed with cold seawater to feed the unit, acting firstas a cooling medium for the condensation of the vapour) and ii) concentration of the brine to dedisposed. The BECC device is based on the principle of evaporative cooling, i.e. a primary liquidstream is cooled by means of a secondary liquid stream (by-pass stream), which in turn evaporatesin contact with atmospheric air, thus being cooled naturally. The two streams are separatedby a heat-conductive surface, through which heat is transferred from the primary stream to thecooling-evaporating by-pass stream. A lab scale BECC pilot unit has been designed, constructedand tested. Geometrical and operating features have been studied in order to allow the operationwith concentrated brines, to minimise problems of corrosion, scaling and fouling. The first resultshave demonstrated the feasibility of the technology and a larger scale prototype unit has beendesigned for the installation within a 5 m3/d solar membrane distillation unit to be constructed inPantelleria Island, Italy.
|Numero di pagine||10|
|Rivista||Desalination and Water Treatment|
|Stato di pubblicazione||Published - 2011|
All Science Journal Classification (ASJC) codes
- Water Science and Technology
- Ocean Engineering