This invention relates to a process and an apparatus Hour the removal of dissolved solids film water, more particularly, though not exclusively a process and an apparatus for the desalination of water.
With increasing awareness of the conservation of water it has almost become obligatory to clean contaminated (impure) water from various sources including ground and marine water. Apart from the organic pollutants, mainly from petrochemical industries, water often contains dissolved inorganic sods. Typicality water from tanneries and metallurgical operations contain undesirable metals. Additionally ground water invariable contains quite a liege amount of inorganic solids. Apart torn the common sodium, calcium and magnesium salts, ground water in certain cases contains dissolved fluorides, arsenic and cadmium. The consequences of these dissolved impurities axe hazardous.

Desalination, particularly of sea water, is a familiar process for removal of these inorganic impurities. Reverse osmosis is a well established technique in this respect. The process invokes passing impure water, under high pressure, through a membrane to get pure water. The process is complex and needs heavy capital investment. The running cost for maintenance is also high. Moreover, the waste water disposal makes it imperative to be located near the sea coast.
Considering these factors, this invention proposes a process and an apparatus to eliminate, or at least greatly minimise, the above mentioned drawbacks.
The process for the removal of dissolved solids from water, according to this invention, comprises the steps of letting in impure water on to a bed of porous, high surface area, hydrophilic adsorbent; allowing solar radiation to thermally activate the adsorption, desertion and evaporation of water from

the adsorbent surface; providing air for agitating the condensation of the evaporated water; and collecting the condensed water in a storage or distribution tank.
The apparatus for the removal of dissolved solids from water, according to this invention, comprises a chamber containing a bed of porous, high surface area hydrophyhc adsorbent; an inlet provided for the chamber for entry of impure water on to the bed at one end mid an outlet provided for the chamber for exit of excess implied water from the bed at its other end : an inclined transparent had provided for the chamber above the bed for allowing solar radiation to pass through and thermally activate the adsorption, adsorption and evaporation of water from the adsorbent surface, the desorbed water condensing on the inner side of the inclined transparent hd and thereafter collecting in the chamber in a trough; means for letting in air through an air inlet into the chamber for facilitating the condensation of water; a second outlet for discharging the condensed water from the trough into a storage or distribution tank.

This invention will now be described with reference
to the accompanying drawings, which illustrate, by
way of example, and not 6y way of limitation, one of
possible embodiments of the apparatus proposed
herein
Fig.l illustrating a top perspective view of the
embodiment
¥'ig, 2 illustrating a front perspective view of the
embodiment
Fig.3 illustrating a side perspective view of the
embodiment.
A chamber C contains a bed B of porous, high surface area hydrophylic adsorbent
An inlet A is provided for the chamber for entry - of impure water (water with dissolved solids e.g. saline water) on to the bed and an outlet O (drain) is provided for the chamber for exit of excess (overflow) impure water from the bed.

An inclined transparent lid L , such as a lid made of glass plate, is provided for the chamber above the bed for allowing solar radiation to pass through and thermally activate tha adsorption, adsorption and evaporation of water from the surface, the desorbed water condensing on the inner side of the transparent had. The chamber is provided with an air inlet J for the entry of air to cool Che inside surface of the glass p]ate and facilitate the condensation of the desorbed water. Accordingly, means, such as, a solar power activated micro compressor is connected to the air inlet J to pomp in air into the chamber and cool it, thus facilitating condensation of the water on the glass plate.
The pure water, as it condenses travels down the inclination of the glass plate and collects in a trough U in the chamber, from which it is discharged through a second outlet T and finally received in a storage or distribution tank for use. This water is acceptably pure for potable purposes.

Periodically, the bed B can be washed to remove solids covering the surface, and re-used .
The terms and expressions herein are of description and not of limitation since various other embodiments of this invention are possible without departing from the scope and ambit of this mention.

We Claim:
1. A process for tile removal of dissolved solids
from water comprising the steps of letting in impure
water on to a bed of porous, high surface area,
hydrophylic adsorbent; allowing solar radiation to
thermo activate the adsorption, adsorption and
evaporation of water from the adsorbent surface;
providing air for facilitating the condensation of the
evaporated water; and collecting the condensed water
in a storage or distribution tank.
2. A process for the removal of dissolved so\ids from water substantially as herein described.
3. An apparatus for the removal of dissolved solids from water comprising a chamber containing a bed of porous, high surface area hydrophylic adsorbent; an inlet provided for the chamber for entry of impure water on to the bed at one end and an outlet provided for the chamber for exit of excess impure -water from the bed at its other end ; an inched transparent had provided for the chamber above the bed for allowing solar radiation to pass through and thermally activate

the adsorption, adsorption and evaporation of water from the adsorbent surface, the desorbed water condensing on the inner side of the inclined transparent lid and thereafter collecting in the chamber in a trough; means for letting in air through an air inlet into the chamber for facilitating the condensation of water: a second outlet for discharging the condensed water from the trough into a storage or distribution tank,
4.An apparatus as claimed in Claim3 wherein the said means consist of a solar power activated micro compressor.
5. An apparatus as claimed in any one of the preceding Claims wherein the lid is made of a transparent glass plate.
6. An apparatus for the removal of dissolved solids water substantially as herein described with reference to, and as illustrated in, the accompanying drawings.