US4465598A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating well servicing fluids
Assignee: Halliburton Energy Services Inc
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Filing: 1983-01-17
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Granted: 1984-08-14
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Expires: 2003-01-17
Abstract
Abstract A method for removing heavy metals from brines used as well servicing fluids in which the heavy metal is oxidized to a higher, stable oxidation state of +3 or greater, the oxide or variants thereof of the oxidized metal is formed resulting in a generally water insoluble precipitate which is then removed by filtration leaving the brine free of deleterious amounts of the heavy metal.
Inventors
- 👤 Roy K. Darlington
- 👤 George Henry, Jr.
- 👤 Jack L. Lowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:47
CPC Classifications
C; C02; C02F; C02F9/00; C02F1/00; C02F1/72; C09; C09K; C09K8/00; C09K8/52; C09K8/528; C02F2101/00; C02F2101/10; C02F2101/20; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/911; Y10S210/912; Y10S210/913
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
126 words
A method of removing heavy metal impurities from an aqueous well servicing fluid comprising adding to said fluid an effective amount of an oxidizing agent having a strength sufficient to oxidize water soluble ions of said heavy metal to a higher oxidization state, forming a generally water insoluble compound of the oxidized form of said heavy metal ion, said heavy metal comprising a transition element having a +3 or higher stable oxidation state, and removing said water insoluble compound from said fluid, said fluid comprising a heavy brine having a density of from about 12 to about 19 pounds per gallon and comprising an aqueous solution of a material selected from the class consisting of calcium chloride, calcium bromide, zinc chloride, zinc bromide, and mixtures thereof.
Claim 2
Independent Claim
126 words
A method of removing heavy metal impurities from an aqueous well servicing fluid comprising adding to said fluid an effective amount of an oxidizing agent having a strength sufficient to oxidize water soluble ions of said heavy metal to a higher oxidization state, forming a generally water insoluble compound of the oxidized form of said heavy metal ion, said heavy metal comprising a transition element having a +3 or higher stable oxidation state, and removing said water insoluble compound from said fluid, said fluid comprising a heavy brine having a density of from about 12 to about 19 pounds per gallon and comprising an aqueous solution of a material selected from the class consisting of calcium chloride, calcium bromide, zinc chloride, zinc bromide, and mixtures thereof.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein said heavy metal is selected from the class consisting of chromium, manganese, iron, cobalt and nickel.
Claim 4
Dependent Claim
46 words
The method of claim 1 wherein said oxidizing agent is selected from the class consisting of (i) a water soluble salt of an anion selected from the class consisting of bromate, peroxysulfate, hydrochlorite, chlorate, iodate, percarbonate, perborate, (ii) hydrogen peroxide, (iii) organic oxidants, and mixtures thereof.
Claim 5
Dependent Claim
14 words
the method of claim 3 wherein said oxidizing agent is an alkali metal bromate.
Claim 6
Dependent Claim
20 words
The method of claim 1 including adjusting the pH with a basic material to effect formation of said insoluble compound.
Claim 7
Dependent Claim
14 words
The method of claim 1 wherein said water insoluble compound is removed by filtering.
Claim 8
Dependent Claim
12 words
The method of claim 1 wherein said fluid contains a viscosifying agent.
Claim 9
Dependent Claim
12 words
The method of claim 7 wherein said viscosifying agent comprises hydroxyethyl cellulose.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-14 | 1988-02-13 | 1988-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-14 | 1992-02-13 | 1992-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-14 | 1996-02-13 | 1996-08-14 | $7700.00 | Window Closed / Lapsed |