Donald Webster Hendricks

US Patent:

49541510, Sep 4, 1990

Filed:

Jan 10, 1989

Appl. No.:

7/295651

Inventors:

Chung-Nan Chang - Los Altos CA
William M. Conlon - Palo Alto CA
Donald M. Hendricks - Moraga CA

Assignee:

Polar Spring Corporation - Menlo Park CA

International Classification:

B01D 904

US Classification:

62532

Abstract:

An improved water purification apparatus and method includes the freeze plate of a refrigeration system disposed in contact with the surface of water to be purified for transferring heat from the water substantially only through the surface and for forming a layer of ice only near the surface that is nearly as thick as the volume of water is deep. Electrostatic field is produced to improve the rejection of impurities at the ice-water interface. System and operating parameters are described for the optimum production of purified water through recurring cycles of freezing, draining, melting, and recovering melt water in batch processing of impure water using a refrigeration system of selected heat-removing capacity.

US Patent:

51136643, May 19, 1992

Filed:

Jan 18, 1991

Appl. No.:

7/643465

Inventors:

William M. Conlon - Palo Alto CA
Donald M. Hendricks - Palo Alto CA

Assignee:

Polar Spring Corporation - Menlo Park CA

International Classification:

C02F 122

US Classification:

62124

Abstract:

Ice formed in a batch crystallization apparatus is melted by causing an ice sheet 20 to be cut into approximately equal size pieces by the knife-edge 32 of melter 26. The pieces of ice are induced to slide against the sides of melter by inclined rails 28. Temperature sensor 40 and controller 44 are used to operate a heater to maintain the melter at a temperature setpoint 54 for a fixed time period while the ice sheet is cut into pieces. While the ice pieces melt the heating means is maintained fully on and the product drain valve is kept open. When the ice has melted the temperature exceeds the setpoint signaling the controller that the melting phase is complete. Failure of the apparatus to freeze ice is diagnosed by the temperature exceeding the setpoint at the end of said time period. Failure of the apparatus to melt ice is diagnosed by the temperature not reaching the setpoint after a sufficient amount of time.

US Patent:

52318524, Aug 3, 1993

Filed:

Apr 7, 1992

Appl. No.:

7/864477

Inventors:

William M. Conlon - Palo Alto CA
Donald M. Hendricks - Woodside CA

Assignee:

Polar Spring Corporation - Menlo Park CA

International Classification:

B01D 904

US Classification:

62532

Abstract:

Ice formed in a batch crystallization apparatus is melted by causing an ice sheet 20 to be cut into approximately equal size pieces by the knife-edge 32 of melter 26. The pieces of ice are induced to slide against the sides of melter by inclined rails 28. Temperature sensor 40 and controller 44 are used to operate a heater to maintain the melter at a temperature setpoint 54 for a fixed time period while the ice sheet is cut into pieces. While the ice pieces melt the heating means is maintained fully on and the product drain valve is kept open. When the ice has melted the temperature exceeds the setpoint signaling the controller that the melting phase is complete. Failure of the apparatus to freeze ice is diagnosed by the temperature exceeding the setpoint at the end of said time period. Failure of the apparatus to melt ice is diagnosed by the temperature not reaching the setpoint after a sufficient amount of time.