COMPOSITE BINDING MATERIAL FROM PHOSPHOGYPSUM AND METHOD FOR ITS PRODUCTION Russian patent published in 2024 - IPC C04B11/26 

FIELD: production of binding materials.

SUBSTANCE: group of inventions relates to a method of producing composite binder from phosphogypsum, which is used in the construction of the base of the pavement and as a gypsum binder having a wide range of applications in construction. Composite binder contains the following components, wt.%: phosphogypsum 65.0–93.5, lignin treated in a drying drum for 15–30 minutes at temperature of 200–350 °C 1–10, bellite—slag sand 0.5–5.0, conversion calcite—balance. Method of producing composite binder involves mixing components of binder and step-by-step indirect heating to temperature of 80±5 °C for 10–12 minutes, to temperature of 95–117 °C for 60–90 seconds with continuous mixing of raw materials and further heat treatment at temperature of 95–117 °C for 15–25 minutes under pressure of not less than 0.1 MPa.

EFFECT: improved strength characteristics of the composite binder, reduced consumption of thermal energy per unit weight of the produced composite binder.

5 cl, 8 tbl, 1 dwg