Desalination plays an ...

Desalination plays an important role in producing pure water from brackish water. Reverse osmosis (RO) is by far the most efficient way to remove colloidal and dissolved silica, which can be found in high concentrations in brackis .Reverse osmosis (RO) is by far the most efficient way to remove colloidal and dissolved silica, which can be found in high concentrations in brackish. In the monsoon season presence of colloidal silica is observed in the raw water (river source).

Precipitation of silica with Fe(OH)3, Al(OH)3 and silica also found

Silica, in general, is reactive  silica  and colloidal silica . Whatever form this constituent is in,  silica must be  removed  before treatment and reuse or disposal/discharge. The most familiar methods for removing silica  from a waste stream are as following..

1.  Ion exchange and  reverse osmosis.
2. Lime softening and
3. RO

The Ultrafiltration membranes are cleaned intermittently to remove any possible gel layering of any foulants. The Ultrafiltration membranes offered are also Chlorine compatible.Microfiltration (as well as sand filtration, cartridge filtration, and diatomaceous earth filtration) would not be effective in removing colloidal silica, some bacteria, smaller particulates, and large molecular weight organics.

Reverse osmosis (RO) is a membrane-technology filtration method that removes many types of large molecules and ions from solutions by applying pressure to the solution when it is on one side of a selective membrane. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be “selective,” this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution, such as the solvent, to pass freely.

Using reverse osmosis or any membrane technology to remove silica can be problematic. Silica is like glass and will cut holes in the membrane and will decrease the efficacy of a membrane because of the abrasiveness of the particles. Heavy metals foul membranes, leading to failure. Membrane systems should have a pre-treatment regimen to get rid of the constituents that foul membranes. If pre-treatment is done prior to membrane treatment, then membranes will perform optimally without expensive replacement.

remove colloidal and dissolved silica, which can be found in high concentrations in brackish water. The presence of silica and its ability to foul membranes limits the use of silica bearing waters for desalination and when used, it has many economic penalties. This study examines the effect of silica... were carried out to examine the actual fouling mechanism in reverse osmosis units under various experimental conditions. Furthermore the effect of cleaning, with distilled water and with pulsations as well as with commercially available cleaners were examined.