 |
| Titel |
Characterization of saline groundwater across the coastal aquifer of Israel as resource for desalination |
| VerfasserIn |
Shaked Stein, Amos Russak, Orit Sivan, Yospeh Yechieli, Yoram Oren, Roni Kasher |
| Konferenz |
EGU General Assembly 2015
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250107323
|
| Publikation (Nr.) |
 EGU/EGU2015-7020.pdf |
|
|
|
|
|
| Zusammenfassung |
| In arid countries with access to marine water seawater desalination is becoming an important
water source in order to deal with the water scarcity and population growth. Seawater reverse
osmosis (RO) facilities use open seawater intake, which requires pretreatment processes to
remove particles in order to avoid fouling of the RO membrane. In small and medium
size desalination facilities, an alternative water source can be saline groundwater
in coastal aquifers. Using saline groundwater from boreholes near the shore as
feed water may have the advantage of natural filtration and low organic content.
It will also reduce operation costs of pretreatment. Another advantage of using
groundwater is its availability in highly populated areas, where planning of large RO
desalination plants is difficult and expensive due to real-estate prices. Pumping
saline groundwater underneath the freshwater-seawater interface (FSI) might shift
the interface towards the sea, thus rehabilitating the fresh water reservoirs in the
aquifer.
In this research, we tested the potential use of saline groundwater in the coastal aquifer of
Israel as feed water for desalination using field work and desalination experiments.
Specifically, we sampled the groundwater from a pumping well 100 m from the
shore of Tel-Aviv and sea water from the desalination plant in Ashqelon, Israel. We
used an RO cross flow system in a pilot plant in order to compare between the two
water types in terms of permeate flux, permeate flux decline, salt rejection of the
membrane and the fouling on the membrane. The feed, brine and fresh desalinated
water from the outlet of the desalination system were chemically analyzed and
compared. Field measurements of dissolved oxygen, temperature, pH and salinity
were also conducted in situ. Additionally, SDI (silt density index), which is an
important index for desalination, and total organic carbon that has a key role in organic
fouling and development of biofouling, were measured and compared. The results
have shown that using saline groundwater underneath the FSI as a resource for
RO desalination process is beneficial in terms of fluxes: the flux reduction in the
seawater desalination was 16% of the initial flux, while the flux reduction with the
saline groundwater was only 9%. The SDI and total organic carbon were lower in
saline groundwater than in seawater, which support the flux results. Therefore, using
saline groundwater as feed water for desalination may be advantageous because of
lower operational costs and reduced applied pressure needed and energy usage. |
|
|
|
|
|
|