Devesh N Sharma, 47Canonsburg, PA

7163964, Jan 16, 2007

Oct 16, 2003

10/687159

Ravi Chidambaran - Canonsburg PA, US
Pavan Raina - Pinnac Kanchan Ganga, IN
Devesh Sharma - Washington PA, US
Narendra Singh Bisht - Punc, IN

Aquatech International Corporation - Canonsburg PA

C08J 5/20
B01J 41/12

521 25, 521 26, 521 27, 521 28, 521 30

This invention presents an ion exchange media including a plurality of cation exchange zones and anion exchange zones in flow paths that are contained in a substantially nonporous resin transport framework. During electrodeionization and other potential applications the ion exchange media of the invention prevents unfavorable water splitting at resin-membrane interfaces and encourages water splitting at resin—resin interfaces where the water splitting may be constructively used to regenerate the resin.

7338600, Mar 4, 2008

Jan 7, 2005

11/030926

Ravi Chidambaran - Canonsburg PA, US
Pavan Raina - Pune, IN
Devesh Sharma - Washington PA, US

Aquatech International Corporation - Canonsburg PA

B01D 61/48
C02F 1/469

210243, 210748, 204524, 204533, 204536, 204632, 204633

A liquid treatment process is described for sequential removal of ionic species of progressively decreasing ionic strength without precipitation or “scaling. ” An aspect of the invention includes two or more electrodeionization operations within one or more electrodeionization stacks. The first electrodeionization operation is performed at a voltage calculated to remove strongly ionized species such as calcium and magnesium from the feed water without scaling. The product of the first electrodeionization operation is then subjected to a second electrodeionization operation. The second electrodeionization operation is performed at a voltage the same as the first electrodeionization operation, and is designed to remove more weakly ionized species such as silica and carbon dioxide, preventing scaling. More than two successive electrodeionization operations may be performed if desired. Multiple electrodeionization operations may occur in a single electrodeionization stack or in multiple electrodeionization stacks.

7705061, Apr 27, 2010

Dec 11, 2006

11/636795

Ravi Chidambaran - Canonsburg PA, US
Pavan Raina - Pune, IN
Devesh Sharma - Washington PA, US
Narendra Singh Bisht - Pune, IN

Aquatech International Corporation - Canonsburg PA

C08J 5/20
B01J 41/12
B01D 61/00

521 25, 521 26, 521 27, 521 28, 521 30, 204522, 204523, 204524, 204632, 204624

This invention presents an ion exchange media including a plurality of cation exchange zones and anion exchange zones in flow paths that are contained in a substantially nonporous resin transport framework. During electrodeionization and other potential applications the ion exchange media of the invention prevents unfavorable water splitting at resin-membrane interfaces and encourages water splitting at resin-resin interfaces where the water splitting may be constructively used to regenerate the resin.

8104624, Jan 31, 2012

Jun 10, 2009

12/481909

Ravi Chidambaran - Canonsburg PA, US
Devesh Sharma - Washington PA, US
Pavan Raina - Pune, IN
Sugata Das - Pune, IN

Aquatech International Corporation - Canonsburg PA

B01D 69/08
B01D 69/00

21050023, 21050041, 21050042, 15624413, 264150, 2642091, 264205

A multipolymeric mixture is provided that includes a hydrophobic polymer, two different grades of a water-soluble polymer, water as non-solvent and a solvent suitable for all polymers involved. The dissolved hydrophobic polymer has the affinity to enmesh the water-soluble polymers to form a clear and viscous dope. Water-soluble polymers contribute to the pore formation process and hydrophilicity of the finally coagulated membrane according to the makeup of their molecular weight distribution. Water as a non-solvent takes the dope very near towards unstable zone, which helps in speeding up the membrane formation process in a diffusion induced phase inversion technique. The dope is then spun through a concentric orifice spinneret and solidified by passing it through a coagulation bath to form hollow fiber asymmetric membranes of ultra filtration grade with superior water permeability and separation characters even at higher feed turbidity.

8424688, Apr 23, 2013

Jan 20, 2012

13/354664

Ravi Chidambaran - Canonsburg PA, US
Devesh Sharma - Washington PA, US
Pavan Raina - Pune, IN
Sugata Das - Pune, IN

Aquatech International Corporation - Canonsburg PA

B01D 33/00
B01D 39/00
B01D 39/14

21050023, 21050041, 21050042

A multipolymeric mixture is provided that includes a hydrophobic polymer, two different grades of a water-soluble polymer, water as non-solvent and a solvent suitable for all polymers involved. The dissolved hydrophobic polymer has the affinity to enmesh the water-soluble polymers to form a clear and viscous dope. Water-soluble polymers contribute to the pore formation process and hydrophilicity of the finally coagulated membrane according to the makeup of their molecular weight distribution. Water as a non-solvent takes the dope very near towards unstable zone, which helps in speeding up the membrane formation process in a diffusion induced phase inversion technique. The dope is then spun through a concentric orifice spinneret and solidified by passing it through a coagulation bath to form hollow fiber asymmetric membranes of ultra filtration grade with superior water permeability and separation characters even at higher feed turbidity.

2003020, Oct 30, 2003

Dec 19, 2002

10/325372

Ravi Chidambaran - Canonsburg PA, US
Devesh Sharma - Washington PA, US
Pavan Raina - Sanewadi, IN

B03C001/00

210/748000

A liquid treatment process is described for sequential removal of ionic species of progressively decreasing ionic strength without precipitation or “scaling.” An embodiment of the invention includes dual electrodeionization operations. The first electrodeionization operation is performed at a voltage calculated to remove strongly ionized species such as calcium and magnesium from the feed water without scaling. The product of the first electrodeionization operation is then subjected to a second electrodeionization operation. The second electrodeionization operation is performed at a voltage greater than the first electrodeionization operation, and is designed to remove more weakly ionized species such as silica and atmospheric carbon dioxide. The danger of precipitation or “scaling” normally present during electrodeionization of weakly ionized species is not present in this invention, because the strongly ionized species responsible for scaling at higher voltages have already been removed from the feed stream through the first electrodeionization operation. More than two successive electrodeionization operations may be performed if desired. Multiple electrodeionization operations may occur in a single electrodeionization stack or in multiple electrodeionization stacks.