Differential recrystallization method of alpha-type semi-hydrated gypsum and pressure vessel

By using crystal correction agents in the pressure vessel for differentiated recrystallization, the problem of insufficient compactness of α-type semi-water gypsum is solved, and high-strength and low-vacuo rate α-type semi-water gypsum products are realized, reducing production costs.

CN119683885APending Publication Date: 2025-03-25TAIYUAN UNIVERSITY OF SCIENCE AND TECHNOLOGY
0 Cites 0 Cited by

Patent Information

Application Number
CN202411695422.5
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-11-25
Publication Date
2025-03-25

AI Technical Summary

Technical Problem

The prior art is difficult to effectively reduce the void ratio of alpha-type hemihydrate gypsum and improve its density, resulting in insufficient density when it hydrates into dihydrate gypsum, affecting the strength of the product.

Method used

By adopting a differentiated recrystallization method, by using the first and second crystal correction agents in the pressure vessel for two crystallization treatments, combined with constant pressure and temperature control, α-type hexaqua gypsum particles with short columnar, long columnar, and hexagonal shapes are formed, and the grading is good.

Benefits of technology

It is realized that α-type semi-water gypsum is denser when hydrated into dihydrate gypsum, reducing gaps, improving product strength, having a strength of more than 30%, and reducing production costs.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

The invention discloses a differential recrystallization method of alpha-type semi-hydrated gypsum and a pressure vessel. The differential recrystallization method comprises the following steps: adding an industrial by-product gypsum raw material containing attached water and a first crystal modifier into the pressure vessel, and carrying out a constant-pressure reaction under a stirring condition; and after the constant-pressure reaction is finished, discharging steam in the pressure container, and taking out the vaporized first crystal modifier by the steam. Heat source steam with the pressure higher than the internal pressure of the pressure container is input into the pressure container, the heat source steam carries a second crystal correcting agent and a dispersing agent, and the stirring procedure in the constant-pressure reaction process is that stirring is conducted for 0.4-0.6 h firstly, and then stirring is stopped; and after the constant-pressure reaction is completed, discharging steam in the pressure container, taking out the vaporized second crystal modifier and dispersant by the steam, and finally, introducing a steam heat source into the pressure container for drying until the generated alpha-type semi-hydrated gypsum is completely dried. The crystal obtained by the invention is more dense and has few gaps when being hydrated into dihydrate gypsum due to differentiated crystallization.
Need to check novelty before this filing date? Find Prior Art