Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Reducing hexavalent chromium type grinding aid and preparing method thereof

A technology of grinding aid and hexavalent chromium, which is applied in the field of cement production, can solve the problems of incomplete removal of hexavalent chromium and human hazards, and achieve low cost, low dosage and good use effect

Active Publication Date: 2018-09-28
安徽海螺材料科技股份有限公司
View PDF5 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] In the existing cement chromium removal technology, ferrous sulfate is easily oxidized by oxygen in the air and becomes invalid under high-temperature grinding and long-term storage conditions, resulting in incomplete removal of hexavalent chromium, and more water-soluble chromium remains in the cement. Hexavalent chromium may cause harm to the human body in contact with it. The invention provides a reduced hexavalent chromium grinding aid and a preparation method thereof. The purpose is to improve the formula of the cement grinding aid so that the sulfuric acid in the cement Ferrous iron can be relatively stable during grinding and long-term storage, so that hexavalent chromium can be removed more completely during cement hydration

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Reducing hexavalent chromium type grinding aid and preparing method thereof
  • Reducing hexavalent chromium type grinding aid and preparing method thereof
  • Reducing hexavalent chromium type grinding aid and preparing method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0036] The invention provides a method for preparing a reduced hexavalent chromium type grinding aid and the reduced hexavalent chromium type grinding aid prepared by the method.

[0037] The preferred mode of this preparation method specifically comprises the following steps:

[0038] (1) Preparation of protective agent (i.e. ferrous sulfate wrapped with organic protective layer)

[0039] (1-1) Prepare polyvinyl alcohol (17-92) into an aqueous solution with a mass percent concentration of 8% to 30%, and add FeSO4·7H2O powdery solid until the solution is saturated and precipitated.

[0040] (1-2) Use a sieve with a pore size of less than 80 μm to filter, remove excess green solids, and leave the saturated solution for later use.

[0041] (1-3) Continue to add polyoxyethylene diamine (PEO—NH2) into the saturated solution obtained in the previous step at a mass fraction of 1%-5% and stir evenly at a speed of 100-200r / min.

[0042] (1-4) Take the solution obtained in step (1-3)...

Embodiment 1

[0056] The grinding aid that present embodiment adopts is prepared by the following steps:

[0057] (1) Preparation of protective agent (i.e. ferrous sulfate wrapped with organic protective layer)

[0058] (1-1) Prepare polyvinyl alcohol (17-92) into an aqueous solution with a mass percent concentration of 8%, and add FeSO4·7H2O powdery solid until the solution is saturated and precipitated.

[0059] (1-2) Use a sieve with a pore size of less than 80 μm to filter, remove excess green solids, and leave the saturated solution for later use.

[0060] (1-3) Continue to add polyoxyethylene diamine (PEO—NH2) into the saturated solution obtained in the previous step at a mass fraction of 1% and stir evenly at a speed of 100-200 r / min.

[0061] (1-4) Get the solution that step (1-3) obtains and add ethylene-vinyl acetate copolymer emulsion (EVA) according to the ratio of mass fraction 15%, in neutral gas CO 2 Under protection, it is spray-dried to obtain a white powdery solid, which...

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

No PUM Login to View More

Abstract

The invention belongs to the technical field of cement production, and particularly relates to a reducing hexavalent chromium type grinding aid and a preparing method thereof. In an existing cement chromium removal technology, ferrous sulfate is prone to being oxidized by oxygen in air and losing efficacy under the conditions of high-temperature grinding and long-term storage, hexavalent chromiumis not completely removed, and a large amount of water-soluble hexavalent chromium is still left in cement and probably causes harm to a contact human body. By means of the technical scheme, the method includes the following steps of firstly, evenly mixing a solution of grinding aid components and ferrous sulfate wrapping an organic protection layer in proportion; secondly, preparing a sodium citrate solution; thirdly, adding ascorbic acid to a mixed solution obtained in the first step to be sufficiently dissolved, and adding the sodium citrate solution obtained in the second step under the heating condition to be evenly stirred to obtain the grinding aid. The grinding aid is suitable for the cement grinding process.

Description

technical field [0001] The invention belongs to the technical field of cement production, and in particular relates to a reduced hexavalent chromium grinding aid and a preparation method thereof. Background technique [0002] As early as 1950, it was discovered in Europe that the soluble chromium compounds in Portland cement can cause serious adverse symptoms to the human body, which is called cement dermatitis. It causes painful, ulcerated skin and can leave nasty scars. Soluble chromium generally refers to chromate or dichromate, in which chromium exists in the form of +6 valence, which is called hexavalent chromium, written as Cr(Ⅵ) or Cr 6+ . Masons and concrete workers are exposed to soluble chromium in cement for a long time, and the above symptoms will slowly appear. [0003] In recent years, the International Agency for Research on Cancer (IARC) has also recognized that hexavalent chromium is a carcinogen, and it invades the human body through inhalation and conta...

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): C04B24/32C04B20/10C04B103/52C04B22/14C04B24/26C04B24/04C04B24/06
CPCC04B20/1037C04B40/0039C04B2103/52C04B22/149C04B24/06C04B24/045C04B24/2623C04B24/32C04B24/122C04B24/02C04B24/10C04B24/18C04B20/1033
Inventor 封培然熊玉兰陆建南
Owner 安徽海螺材料科技股份有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com