Method for preparing phosphogypsum base cementing material by two-step calcining

A phosphogypsum and calcination technology, applied in the field of building materials, can solve the problems of long cement setting time and affect the appearance of products, and achieve the effects of improving the gelling performance, reducing the calcining temperature, and improving the decomposition rate.

Inactive Publication Date: 2018-05-08
MAANSHAN TUORUI METAL SURFACE TECH
View PDF2 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the presence of soluble P and F, the cement will be excessively hydrated, causing the cement to set for too long; the soluble P in phosphogypsum 2 o 5 It will affect the appearance and morphology of the phosphogypsum cementitious material after hydration and hardening

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0018] A two-step calcination method for preparing phosphogypsum-based cementitious materials. The phosphogypsum is washed with water and pickled, followed by deep impurity removal and purification, followed by mixed grinding of fly ash and activated carbon, rapid dehydration, and high-temperature sintering in a reducing atmosphere. Two-stage calcination to obtain phosphogypsum-based cementitious materials.

[0019] Specific steps are as follows:

[0020] (1) Put 90 parts of phosphogypsum into the water according to the liquid-solid ratio of 3:1, stir thoroughly for 15 minutes, and after standing still for 40 minutes, pour out the upper layer of water, rinse 3 times in this way, and dry at 55°C 10 hours;

[0021] (2) According to the liquid-solid ratio of 10:1, add the above-mentioned washed phosphogypsum into the prepared 30% sulfuric acid solution, and stir and pickle for 40 minutes at a temperature of 85°C and a stirring speed of 300r / min. Quickly filter, the filter cake ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
specific surface areaaaaaaaaaaa
specific surface areaaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing a phosphogypsum base cementing material by two-step calcining. The method comprises the following steps: performing washing on the phosphogypsum with water and acid, so as to effectively promote the rate of crystallization transformation of CaSO4.2H2O in phosphogypsum to anhydrous CaSO4, improve the content of anhydrous CaSO4 in the phosphogypsum, realize the deep purification of the phosphogypsum, avoid the influence on calcining by impurity, and reduce calcining temperature, then mixing and grinding the coal ash and activated carbon, and then performing tow-stage calcining including quickly-calcining for dewatering, and sintering under reducing atmosphere and high temperature to obtain the phosphogypsum base cementing material. The inventionhas the advantages that the activated carbon and the coal ash are added, so that the reducing atmosphere is provided for decomposition of the phosphogypsum, the decomposition of the phosphogypsum ispromoted and the decomposition rate of the phosphogypsum is improved.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a method for preparing a phosphogypsum-based cementitious material by two-step calcination. Background technique [0002] Phosphogypsum is a by-product of wet process phosphoric acid production and its main component is CaSO 4 2H 2 O, which also contains some H + , soluble P 2 o 5 And some impurities such as F. These impurities limit the comprehensive utilization of phosphogypsum. The application of phosphogypsum in building materials mainly includes building gypsum powder, gypsum board and gypsum block, used as cement retarder and sulfuric acid co-production cement. However, due to the presence of soluble P and F, the cement will be excessively hydrated, causing the cement to set for too long; the soluble P in phosphogypsum 2 o 5 It will affect the appearance and morphology of the product after hydration and hardening of the phosphogypsum cementiti...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B11/26
CPCC04B11/26
Inventor 芮明功
Owner MAANSHAN TUORUI METAL SURFACE TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap