← Back to Patent Explorer
US3879288A Expired / Lapsed US ⏱️ 0.0 years remaining

Process of inhibiting scale formation on walls of structures containing an aqueous system

Assignee: Individual
•
Filing: 1972-12-13
•
Granted: 1975-04-22
•
Expires: 1992-12-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Formation of hard adherent scale deposits of insoluble salts particularly carbonates and sulfates of metals such as calcium or other alkaline earth metals, and/or iron are inhibited, controlled or prevented on, or removed from (a) the walls of evaporators, cooling towers, heat exchangers, boilers and devices where a thermal gradient exists or areas where catalytically active sites induce scale formation in aqueous systems by (b) from about 2/10 to 2,000 parts per million of an aliphatic copolymer of monovinyl compound and a vinyl sulfonate having (c) from about 25 to 75 mol percent of the sulfonate and (d) a molecular weight of about 1,000 to 25,000. The copolymer is useful alone, and in cooperation with corrosion inhibitors, other sequestrants and chelating agents.

Inventors

  • 👤 Frederick Herman Siegele

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 06:42
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C08; C08F; C08F22/00; C08F28/00

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 42 words
A PROCESS FOR THE CONTROL OF HARD, ADHERENT SCALES ON THE WALLS OF VESSELS OR PIPES CONTAINING AN AQUEOUS SYSTEM WHICH COMPRISES: ADDING FROM 20 TO 200 PARTS PER MILLION OF A WATER SOLUBLE COPOLYMER WHICH IN ACID FORM HAS THE STRUCTURE:
Claim 2
Dependent Claim 42 words
A PROCESS FOR THE CONTROL OF HARD, ADHERENT SCALES ON THE WALLS OF VESSELS OR PIPES CONTAINING AN AQUEOUS SYSTEM WHICH COMPRISES: ADDING FROM 20 TO 200 PARTS PER MILLION OF A WATER SOLUBLE COPOLYMER WHICH IN ACID FORM HAS THE STRUCTURE:
Claim 3
Dependent Claim 42 words
A process for the control of hard, adherent scales on the walls of vessels or pipes containing an aqueous system which comprises: adding from 20 to 200 parts per million of a water soluble copolymer which in acid form has the structure:
Claim 4
Dependent Claim 42 words
A process for the control of hard, adherent scales on the walls of vessels or pipes containing an aqueous system which comprises: adding from 20 to 200 parts per million of a water soluble copolymer which in acid form has the structure:
Claim 5
Dependent Claim 75 words
THE PROCESS ACCORDING TO CLAIM 1 IN WHICH THE WATER SOLUBLE SALT OF THE COPOLYMER IS THE SODIUM ACID SALT OF A COPOLYMER OF ALLYL SULFONATE FUMARATE HAVING AN AVERAGE MOLECULAR WEIGHT OF ABOUT 5,000 AND WITH THE PRESENCE FROM ZINC ION IN THE AQUEOUS SYSTEM, SAID ZINC ION DERIVED FROM THE ADDITION OF A WATER SOLUBLE ZINC SALT SUCH AS ZINC SULFATE IN A WEIGHT AMOUNT OF FROM ONE TO THREE TIMES AND COPOLYMER.

References Cited (Backward Citations)

US3714066A Cited
US3682224A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-04-21 1978-10-21 1979-04-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-04-21 1982-10-21 1983-04-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-04-21 1986-10-21 1987-04-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag