EP0104904A1
Expired / Lapsed
EP
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Compositions comprising mineral particles in suspension and method of treating aqueous systems therewith
Assignee: Blue Circle Industries PLC
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Filing: 1983-09-23
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Granted: —
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Expires: 2003-09-23
Abstract
Abstract An aqueous slurry of mineral particles, for example calcium carbonate and/or calcium hydroxide, has a mineral solids concentration of at least 40% m/m and contains an agent that maintains the slurry at a pumpable viscosity but that acts as a flocculant upon dilution of the slurry. Suitable agents include cationic and amphoteric polyelectrolytes having nitrogen-containing groups, for example polyamines and dimethyl diallyl ammonium chloride polymers. The slurries may contain, other components, for example a synthetic hectorite or a dispersing agent such as a polyacrylate, polymethacrylate or polyphosphate. The slurries are useful in papermaking and in the treatment of sewage.
Inventors
- 👤 Christine Anne Beckett
- 👤 Kenneth Bradlaw Matthews
- 👤 David Ernest Smith
- 👤 Richard Robertson Davidson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 20:08
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5236; C02F1/5227; C02F1/54; D; D21; D21H; D21H17/00; D21H17/63; D21H17/67; D21H17/69
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
69 words
A composition for treating an aqueous system, which composition comprises (a) an aqueous slurry of mineral particles of at least 40% m/m mineral solids concentration, characterised in that it also comprises (b) an agent that at least substantially maintains the mobility of the slurry (a) and that exerts a flocculating action upon addition of the composition to an aqueous system at a dilution ratio of at least 20:1 (m/m).
Claim 2
Dependent Claim
69 words
A composition for treating an aqueous system, which composition comprises (a) an aqueous slurry of mineral particles of at least 40% m/m mineral solids concentration, characterised in that it also comprises (b) an agent that at least substantially maintains the mobility of the slurry (a) and that exerts a flocculating action upon addition of the composition to an aqueous system at a dilution ratio of at least 20:1 (m/m).
Claim 3
Dependent Claim
46 words
A composition according to claim 1, characterised in that the mineral particles are selected from alkaline earth metal oxides, alkaline earth metal hydroxides, alkaline earth metal carbonates, alkaline earth metal bicarbonates, clay, talc, titanium oxide, zinc oxide, lithopone, barium sulphate, and mixtures of any of these.
Claim 4
Dependent Claim
22 words
A composition according to claim 1, characterised in that the mineral particles are selected from calcium carbonate, calcium hydroxide and mixtures thereof.
Claim 5
Dependent Claim
29 words
A composition according to claim 3, characterised in that the mineral particles comprises a mixture of calcium carbonate and calcium hydroxide at a weight ratio of 19:1 to 1:19.
Claim 6
Dependent Claim
21 words
A composition according to claim 1, characterised in that component (b) is selected.from cationic and amphoteric polyelectrolytes that have nitrogen-containing groups.
Claim 7
Dependent Claim
30 words
A composition according to claim 5, characterised in that the component (b) is selected from polyamines, dimethyl diallyl ammonium.chloride homopolymers, dimethyl diallyl ammonium chloride/acrylamide copolymers and mixtures of-any of these.
Claim 8
Dependent Claim
26 words
A composition according to claim 3 or 4, characterised in that the mineral particles comprise calcium hydroxide particles and the component (b) comprises an anionic polymer.
Claim 9
Dependent Claim
26 words
A composition according to claim 1, characterised in that component (b) is present in an amount of from 0.0075% to 2% on a dry weight basis.
Claim 10
Dependent Claim
24 words
A composition according to claim 1, characterised in that it comprises one or more components selected from (c) structure-modifying agents and (d) dispersing agents,
Claim 11
Dependent Claim
33 words
A method of treating an aqueous system, characterised in that there is applied to said system a composition according to claim 1, which composition is applied as such or after having been diluted.
Claim 12
Dependent Claim
36 words
A method according to claim 10, characterised in that the composition is added at a rate of from 100 to 1000 ppm on a dry mineral basis relative to the total. aqueous system to be treated.
Claim 13
Dependent Claim
28 words
A method according to claim 11, characterised in that the aqueous system to be treated is selected from sewage and other waste waters requiring clarification, and papermaking stock.
Claim 14
Dependent Claim
31 words
A method according to claim 12, wherein the aqueous system is sewage, characterised in that alum is added to the system after the application of the composition according to claim 1.
References Cited (Backward Citations)
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