Water control system using oxidation reduction potential sensing

• US 5,342,510 A
• Filed: 07/30/1993
• Issued: 08/30/1994
• Est. Priority Date: 02/03/1992
• Status: Expired due to Fees

• Current Assignee: H.E.R.C. Products, Inc.
• Original Assignee: H.E.R.C. Incorporated
• Inventors: Ludwig, Jerome H., Eden, Todd R.
• Primary Examiner(s): Drodge, Joseph W.
• Application Number:
  US08/099,737
• Time in Patent Office: 396 Days
• Field of Search: 210/85, 210/96.1, 210/143, 210/198.1, 210/696, 210/698, 210/700, 210/699, 210/743, 210/746, 210/764, 204/406, 204/433, 204/153, 204/21, 324/71.1, 324/71.5, 324/438, 137/5, 137/93, 134/22.14, 134/22.19, 134/56 R
• US Class Current: 210/96.1
• CPC Class Codes: B01J 19/0006 Controlling or regulating processes controlling or regulating in general G05
• CPC Class Codes: C02F 1/008 Control or steering systems not provided for elsewhere in subclass C02F
• CPC Class Codes: C02F 1/686 Devices for dosing liquid additives
• CPC Class Codes: C02F 2103/023 Water in cooling circuits
• CPC Class Codes: C02F 2209/008 comprising telecommunication features, e.g. modems or antennas
• CPC Class Codes: C02F 2209/04 Oxidation reduction potential [ORP]
• CPC Class Codes: C02F 2209/05 Conductivity or salinity
• CPC Class Codes: C02F 2209/06 pH
• CPC Class Codes: C02F 5/08 Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
• CPC Class Codes: G01N 33/18 Water
• CPC Class Codes: G05D 21/02 characterised by the use of electric means

Abstract

An automatic control system for maintaining the quality of water in a cooling tower utilizes a probe (38) which senses the oxygen reduction potential (ORP) of a soap having a 1:1 stoichiometric equivalent of an organic acid and ammonia in the water. The soap is pumped from a chemical supply means (20) containing the soap in response to the ORP of the soap in the water falling below a predetermined threshold. A second sensing probe measures the conductivity (in MHos) of the water as a factor of the total dissolved solids (TDS) to control the bleed-off or blow-down of the water. The chemicals, which are supplied for maintaining the ORP, permit significantly higher total dissolved solids in the water than with standard cooling tower systems, without the buildup of scale. As a consequence, water consumption is significantly reduced; and the system functions automatically, without requiring periodic visual inspection, water analysis or manual operation.

Claims

1. An automatic control system adapted for controlling scale formation in a water circulating system comprising:

first sensing means for measuring the oxygen reduction potential (ORP) of the circulating water containing a soap having a 1;

1 stoichiometric equivalent of an organic acid and ammonia in the water for controlling scale formation in said system and

supply means for automatically supplying said soap in response to a predetermined ORP measured by said first sensing means substantially corresponding to a pH higher or lower than a selected range for controlling said scale.

2. The system according to claim 1 further including:

second sensing means for measuring the conductivity of the water as a factor of total dissolved solids (TDS) in the water and

means coupled with said second sensing means for removing water in response to the measurement of a predetermined conductivity of the water by said second sensing means.

3. The system according to claim 2 wherein said means for removing water removes a predetermined quantity of water from the system in response to the measurement of a predetermined conductivity of such water by said second sensing means.

4. The system according to claim 2 wherein said means for removing water includes a normally-closed drain valve means;

and

means for opening said normally-closed drain valve means for a predetermined time interval in response to the measurement of said predetermined conductivity of the water by said second sensing means.

5. The system according to claim 4 further including biocidal feeder means being coupled with said second sensing means for supplying biocidal chemicals to said water in response to the measurement of said predetermined conductivity of said water by said second sensing means.

6. The system according to claim 1 wherein the water is recirculated by a pump through a recirculating conduit, and said first sensing means senses the soap in water supplied through the conduit by the pump.

7. The system according to claim 6 further including:

a shunt conduit coupled across at least a portion of the recirculating conduit so that said first sensing means senses the soap in water flowing through said shunt conduit.

8. The system according to claim 1 wherein said soap in said supply means is in liquid form, and further including a pump for removing said soap from said supply means to supply said soap to said water, said pump being coupled with said first sensing means and operated in response to the sensing of the predetermined ORP measured by said first sensing means.

9. The system according to claim 1 wherein said soap in said supply means is in liquid form, and further including a pump for removing soap from said supply means and for supplying said soap to said water, said pump coupled with said first sensing means and operated in response to the sensing of a predetermined ORP measured by said first sensing means.

10. The system according to claim 1 wherein the organic acid is a carboxylic or sulfonic acid.

11. The system according to claim 10 wherein the organic acid is selected from the group consisting of hydroxyacetic, acetic, citric and benzoic, and mixtures thereof.