Zeolite-based lightweight concrete products
AssigneeNational Research Council of Canada
InventorsYan Fu, Jian Ding, James J. Beaudoin
Life of this patent
Estimating the term…
Abstract
Lightweight concrete products, useful for example in blocks, wall panels, floor and roof slabs, in which zeolite is a major component, its content in the cementing material of the products exceeding 50 wt. %. Depending on application, zeolite may be non-treated or calcined at a temperature enabling the surface activation of the zeolite and resulting high surface energy. Zeolite thus treated will work as both pozzolanic material and bubble-generating agent. Strengthening agents are used to improve compressive strength of the products. Also, a binding material, useful for hazardous waste stabilization, comprising zeolite as a major component, is proposed.
Claims23
A lightweight concrete product comprising 40-100 wt. % cementing material and 0-60 wt. % aggregate, and having dry bulk density 300-1600 kg/m.sup.3 and compressive strength 0.3-35 MPa after 3-6 hours autoclave curing at 170.degree.-180.degree. C. or after 8-14 hours moist-curing at 75.degree.-85.degree. C., or after 28 days moist-curing at 23.degree. C., wherein said cementing material comprises about 50-80 wt. % of zeolite which is either non-calcined or calcined above 800.degree. C., 20-49 wt. % Portland cement and 1-8 wt. % strengthening agent.
A lightweight concrete product comprising 40-100 wt. % cementing material and 0-60 wt. % aggregate, and having dry bulk density 1000-1600 kg/m.sup.3 and compressive strength 4-18 MPa after 3-6 hours autoclave curing at 170.degree.-180.degree. C. or after 8-14 hours moist-curing at 75.degree.-85.degree. C., or after 28 days moist-curing at 23.degree. C., wherein the cementing material comprises 60-80 wt. % zeolite which is either non-calcined or calcined at above 800.degree. C. 10-20 wt % lime, 0-15 wt % silica flour and 1-8 wt. % strengthening agent.
A lightweight concrete product comprising 40-100 wt. % cementing material and 0-60 wt. % aggregate, and having compressive strength 0.3-12 MPa and dry bulk density of 300-1100 kg/m.sup.3 after 3-6 hours of autoclave curing at 170.degree.-180.degree. C., wherein the cementing material comprises 55-79 wt. % of zeolite calcined at 400.degree.-600.degree. C., 20-44 wt. % Portland cement, 0-5 wt. % lime, 0-10 wt. % silica flour and 1-8 wt. % strengthening agent.
A binding material for use in hazardous waste stabilization, comprising 40-60 wt. % zeolite, 15-20 wt. % lime, 15-20 wt. % calcium sulphate hemihydrate (CaSO.sub.4 .circle-solid.1/2H.sub.2 O), 3-8 wt. % sodium sulphate and 0-8 wt. % aluminum sulphate, having a setting time about 10-20 minutes and compressive strength 5-15 MPa after 28 days moist-curing at 23.degree. C. or after 8-14 hours moist-curing at 75.degree.-85.degree. C.
Dependencies are inferred from the claim text.