# US 2014/0190895 A1 · Calcium salfate scale -inhibiting compositions

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2014/0190895 A1
- Document ID: US20140190895A1
- Status: Published application
- Kind: A1
- Application number: 13/737,900
- Filed: 2013-01-09
- Published: 2014-07-10
- Earliest claimed: 2013-01-09
- Assignees: King Abdulaziz City for Science and Technology; King Fahd University of Petroleum and Minerals
- Inventors: FAIZUR RAHMAN; SHAIKH ASROF ALI
- Web page: https://patentgrep.com/patent/US20140190895A1

## CPC

- C02F 1/68: by addition of specified substances, e.g. trace elements, for ameliorating potable water (medicinal water A61K)
- C02F 5/14: containing phosphorus
- C08G 75/22: Copolymers of sulfur dioxide with unsaturated aliphatic compounds
- C02F 2103/08: Seawater, e.g. for desalination
- Y02A 20/131: Reverse-osmosis
- C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes)
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE

## Abstract

The calcium sulfate scale-inhibiting compositions are polyelectrolyte antiscalant compositions for the inhibition of calcium sulfate scale formation in desalination plant feed brine, such as that typically used with reverse osmosis desalination plants. In order to inhibit the formation of calcium sulfate scale, the polyelectrolyte antiscalant compositions are mixed at a concentration between approximately 1 ppm and approximately 50 ppm into the desalination plant feed brine. The polyelectrolyte antiscalant composition may be either poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide), poly[sodium 5-(diallylcarboxymethylammonio)pentanoate]-alt-(sulfur dioxide), or poly[sodium 5-(diallylcarboxymethylammonio)pentanoate].

## Claims

### Claim 1

A calcium sulfate scale-inhibiting composition, comprising poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide).

### Claim 2

A method of inhibiting calcium sulfate scale formation in desalination plant feed brine, comprising the step of mixing poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide) at a concentration between 1 ppm and 50 ppm into desalination plant feed brine.

### Claim 3 (depends on 2)

The method of inhibiting calcium sulfate scale formation in desalination plant feed water as recited in claim 2, wherein the poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide) is mixed into the desalination plant feed brine at a concentration of approximately 10 ppm.

### Claim 4

A method of inhibiting calcium sulfate scale formation in desalination plant feed brine, comprising the step of mixing a polyelectrolyte antiscalant composition at a concentration between 1 ppm and 50 ppm into desalination plant feed brine.

### Claim 5 (depends on 4)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine as recited in claim 4, wherein the polyelectrolyte antiscalant composition comprises poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide).

### Claim 6 (depends on 5)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine according to claim 5, wherein said step of mixing comprises mixing poly[disodium 3-(diallylamino)propanephosphonate]-alt-(sulfur dioxide) into the desalination feed brine to a concentration of about 10 ppm of the feed brine.

### Claim 7 (depends on 4)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine as recited in claim 4, wherein the polyelectrolyte antiscalant composition comprises poly[sodium 5-(diallylcarboxymethylammonio)pentanoate]-alt-(sulfur dioxide).

### Claim 8 (depends on 7)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine according to claim 7, wherein said step of mixing comprises mixing poly[sodium 5-(diallylcarboxymethylammonio)pentanoate]-alt-(sulfur dioxide) into the desalination feed brine to a concentration of about 10 ppm of the feed brine.

### Claim 9 (depends on 4)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine as recited in claim 4, wherein the polyelectrolyte antiscalant composition comprises poly[sodium 5-(diallylcarboxymethylammonio)pentanoate].

### Claim 10 (depends on 9)

The method of inhibiting calcium sulfate scale formation in desalination plant feed brine according to claim 9, wherein said step of mixing comprises mixing poly[sodium 5-(diallylcarboxymethylammonio)pentanoate] into the desalination feed brine to a concentration of about 10 ppm of the feed brine.