IRON-OXIDE PORTLAND CEMENT FOR CORE CATCHER OF NUCLEAR REACTOR Russian patent published in 2021 - IPC C04B7/52 G21C9/16 

FIELD: cements.

SUBSTANCE: invention relates to systems for ensuring localisation of the core melt of water-cooled tank reactors in the event of a beyond design basis accident. The composition of an iron oxide Portland cement contains pre-made Portland cement of a class no lower than 42.5 as a binding substance, iron oxide III is used as an active mineral additive and C-3 superplasticiser is used as a surface-active agent at the following ratio of components, % wt.: Portland cement 30 to 50, iron oxide III 50 to 70, C-3 superplasticiser 1 to 2 over 100% of the rest of the components. The method for preparing an iron oxide cement consists in dry grinding of the components to reach a specific surface area of 7000 to 10000 cm²/g, then gauging the resulting mixture with water at a water/cement ratio of 0.16 to 0.25, followed by hardening for 28 days with a compressive strength of at least 20 MPa and apparent density 2.40 to 2.85 g/cm³.

EFFECT: producing a composition with the maximum possible iron oxide content, the minimum possible content of physically and chemically bound water, reduced water requirement, increased apparent density and a specified compressive strength of no less than 20 MPa.

4 cl, 1 tbl