Lime-based cement extender compositions, and associated systems and methods
A composition configured to be mixed with cement, and associated systems and methods are disclosed herein. In some embodiments, the composition includes at least 10% by weight lime particles, and at least 35% by weight pozzolan particles. Properties of the composition can include a magnesium oxide concentration of at least 0.5%, and an iron oxide concentration of at least 0.5-2.0%, an aluminum oxide concentration of 2-8%, a silicon dioxide concentration of 20-40%, a potassium oxide concentration of 20,000-30,000 ppm, and a sodium oxide concentration of 10,000-20,000 ppm. In some embodiments, the lime-based cement extender composition, or product, is combined with cement to produce a cement blend for use in the mining industry as mine backfill.
1. A cement blend, comprising:
cement; and
a cement extender composition comprising:
lime particles comprising at least 10% by weight of the composition, and
pozzolan particles comprising at least 35% by weight of the composition,
wherein properties of the composition include (i) a magnesium oxide concentration of at least 0.5%, and (ii) an iron oxide concentration of at least 0.5%;
wherein the cement extender composition comprises at least 20% of the cement blend.
2. The cement blend of claim 1 , wherein the cement blend consists of the cement and the cement extender.
3. The cementblend of claim 1 , wherein the cement comprises at least 45% of the cement blend.
4. The cement blend of claim 1 , wherein the cement blend does not include fly ash.
5. The cement blend of claim 1 , wherein the cement extender composition comprises at least 20% limestone.
6. The cement blend of claim 1 , wherein the cement extender composition comprises no more than 70% pozzolan.
7. The cementblend of claim 1 , wherein, after at least 28 days of being formed, the unconfined compressive strength of the cement blend is at least 11 MPa.
8. The cement blend of claim 1 , wherein, after at least 7 days of being formed, the unconfined compressive strength of the cement blend is at least 8 MPa.
9. The cement blend of claim 1 , wherein at least 50% of the cement extender is less than 75 microns.
10. The cement blend of claim 1 , wherein the composition does not include fly ash.
11. A composition configured to be mixed with cement, the composition comprising:
lime particles comprising more than 20% by weight of the composition; and
pozzolan particles comprising at least 35% by weight of the composition,
wherein the pozzolan particles do not include fly ash, and
wherein the pozzolan particles include:
a magnesium oxide concentration of at least 0.5%;
an iron oxide concentration of at least 0.5%;
an aluminum oxide concentration of at least 2%; and
a silicon dioxide concentration of at least 20%.
12. The composition of claim 11 , wherein the composition comprises at least 20% limestone.
13. The composition of claim 11 , wherein the composition comprises at least 20% limestone, and wherein the limestone comprises at least one of high-calcium limestone, precipitated calcium carbonate, argillaceous limestone or dolomitic limestone.
14. The composition of claim 11 , wherein at least 50% of the composition is less than 75 microns.
15. The composition of claim 11 , wherein the lime particles comprise a calcium concentration of at least 90% by weight.
16. A composition configured to be mixed with cement, the composition comprising:
limestone particles;
lime particles comprising at least 10% by weight of the composition; and
pozzolan particles comprising at least 35% by weight of the composition,
wherein the pozzolan particles include (i) a magnesium oxide concentration of at least 0.5%, and (ii) an iron oxide concentration of at least 0.5%.
17. The composition of claim 16 , wherein at least 50% of the composition is less than 75 microns.