US 2017/0022107 A1 · SYNTHESIS AND APPLICATION OF CaSO4-BASED HARDENING ACCELERATORS

Abstract

The invention concerns a method for producing pulverulent hardening accelerators by reactive spray drying, where an aqueous phase I comprising calcium ions, and an aqueous phase II comprising sulphate ions, the molar ratio of the calcium ions to the sulphate ions being from 1/5 to 5/1, are contacted at a spray nozzle, and the phases I and II contacted with one another at the spray nozzle are sprayed in a streaming environment of drying gas. Likewise concerned are the pulverulent hardening accelerators producible by the method of the invention, and their use for accelerating the hardening of bassanite and/or anhydrite with formation of gypsum.

Claims24

Dependent claims

A method for producing a pulverulent CaSO4-based hardening accelerator, the method comprising:

a) contacting, at a spray nozzle, an aqueous phase I comprising liquid calcium ions and an aqueous phase H comprising liquid sulphate ions, the molar ratio of the calcium ions in phase I to the sulphate ions in phase II being from 1/5 to 5/1, and
b) spraying phases I and II from said contacting with one another at the spray nozzle into a streaming environment of drying gas with an entry temperature in the range from 120 to 300° C. and an exit temperature in the range from 60 to 120° C., wherein
the calcium ions react with the sulphate ions and, with removal of water by the carrier gas, the pulverulent hardening accelerator is obtained.

Dependencies are inferred from the claim text.

SYNTHESIS AND APPLICATION OF CaSO4-BASED HARDENING ACCELERATORS

Life of this patent

SYNTHESIS AND APPLICATION OF CaSO4-BASED HARDENING ACCELERATORS

Life of this patent

Abstract

Claims24