Slurry of manganomanganic oxide particles and method for the production of slurry

• US 8,668,772 B2
• Filed: 09/14/2011
• Issued: 03/11/2014
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Elkem
• Original Assignee: Elkem
• Inventors: Al-Bagoury, Mohamed, Rostol, Frank Vidar
• Primary Examiner(s): Green, Anthony J
• Application Number:
  US13/824,092
• Publication Number:
  US 20130319295A1
• Time in Patent Office: 909 Days
• Field of Search: 106/287.18, 106/401, 106/505, 106/810
• US Class Current: 106/287.18
• CPC Class Codes: C04B 14/062 Microsilica, e.g. colloïdal silica preparing microsilica slurries or suspensions C04B18/148
• CPC Class Codes: C04B 14/30 Oxides other than silica ferrites C04B14/363
• CPC Class Codes: C04B 18/146 Silica fume
• CPC Class Codes: C04B 2103/20 Retarders
• CPC Class Codes: C04B 2103/408 Dispersants
• CPC Class Codes: C04B 2103/46 Water-loss or fluid-loss reducers, hygroscopic or hydrophilic agents, water retention agents
• CPC Class Codes: C04B 22/062 of the alkali or alkaline-earth metals
• CPC Class Codes: C04B 24/2647 containing polyether side chains
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C09K 8/032 Inorganic additives
• CPC Class Codes: C09K 8/42 Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells compositions for plastering C09K8/50
• CPC Class Codes: C09K 8/467 containing additives for specific purposes
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A stable non-settling slurry of water and manganomanganic oxide particles having a particle size below 10 μm. The slurry comprises water and up to 92 wt % manganomanganic oxide particles bade on the weight of the slurry. The slurry has a pH between 9 and 11 and contains 0.05 to 0.5 wt % of a dispersant based on the weight of dry manganomanganic oxide particles. The dispersant can be an ethoxylated polycarboxylate or a polyacrylic acid salt and has a molecular weight between 500 and 50 000 g/mol.

Claims

1. A stable, non-settling slurry comprising:

water;

manganomanganic oxide particles having a particle size below 10 μ

m, the manganomanganic oxide particles present in the slurry in an amount up to 92 wt % based on the weight of the slurry;

a dispersant in an amount of 0.05 to 0.5 wt % based on the weight of dry manganomanganic oxide particles in the slurry, the dispersant having a molecular weight between 500 and 50,000 g/mol and selected from an ethoxylated polycarboxylate and a polyacrylic acid salt; and

a ph of the slurry being 9 to 11.

2. The slurry of claim 1, wherein the amount of the manganomanganic particles present in the slurry is greater than 80 wt % based on the weight of the slurry.

3. The slurry of claim 1, wherein the amount of the dispersant is 0.07 to 0.15 wt % based on the weight of dry manganomanganic oxide particles.

4. The slurry of claim 1, wherein:

the dispersant is a polyacrylic sodium salt having a molecular weight of about 3000 g/mol.

5. The slurry of claim 1, wherein:

the dispersant is an ethoxylated polycarboxylate;

with a hydrophobic chain as a side chain.

6. The slurry of claim 1, wherein:

the ethoxylated polycarboxylate has a molecular weight of about 20,000 g/mol.

7. The slurry of claim 1, wherein:

the ph of the slurry is 9.5 to 10.5.

8. The slurry of claim 1, wherein the ph of the slurry is adjusted using sodium hydroxide.

13. An oil well cement composition comprising cement powder, water and the slurry of claim 1.

9. A method of producing a stable, non-settling aqueous slurry of manganomanganic oxide, comprising:

Mixing manganomanganic oxide particles, water and a dispersant to form a slurry, wherein the manganomanganic oxide particles have a particle size below 10 and are presentin an amount up to 92 wt % based on the weight of the slurry, the dispersant is present in an amount of 0.05 to 0.5 wt % based on the weight of the dry manganoanganic oxide particles present in the slurry, the dispersant is selected from an ethoxylated polycarboxylate and a polyacrylic acid salt; and

the dispersant has a molecular weight of 500 to 50,000 g/mol; and

adjusting the ph of the slurry from 9 to 11.

10. The method of claim 9, wherein:

first, dispersant is added and mixed with the water;

second, sodium hydroxide is added and mixed with the dispersant and water mixture;

third, the manganomanganic oxide particles are added and mixed with the water, dispersant and sodium hydroxide mixture at a low rate of mixing;

fourth, after adding all of the manganomanganic oxide particles to the water, dispersant and sodium hydroxide mixture, a high rate of shear is applied to the water, dispersant, sodium hydroxide and manganomanganic oxide particle mixture to form the slurry.

11. The method of claim 9 wherein:

the ph of the slurry is adjusted with sodium hydroxide.

12. The method of claim 9, further comprising:

pumping the slurry through a sieve system to remove coarse particles having a diameter greater than 45 μ

m from the slurry, after the slurry has been prepared.