Process for Bayer process aluminum oxide production by replacing carbide slag with lime

A technology of calcium carbide slag and alumina, which is applied to the removal of alumina/hydroxide and solid waste, can solve the problems of high cost, adverse impact on the surrounding environment, and occupation of land, so as to solve the problem of difficult storage and realize the recycling of waste , The effect of reducing raw material consumption

Active Publication Date: 2010-05-19
CHIPING XINFA HUAYU ALUMINA
View PDF0 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The storage of calcium carbide slag, the waste produced by chemical plants, not only occupies land and costs a lot, but also if the anti-seepage and dust-proof treatment is not good, it will cause serious adverse effects on the surrounding environment, especially the groundwater and surrounding villages, which is a major safety hazard in chemical production Therefore, the storage of calcium carbide slag has always been a difficult problem for chemical plants, and how to recycle it is imminent

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
  • Process for Bayer process aluminum oxide production by replacing carbide slag with lime
  • Process for Bayer process aluminum oxide production by replacing carbide slag with lime
  • Process for Bayer process aluminum oxide production by replacing carbide slag with lime

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] The process of using calcium carbide slag instead of lime for Bayer process alumina production includes the following steps:

[0020] (1) the waste calcium carbide slag that chemical plant produces PVC, moisture content is at 25% (wt%), and available calcium oxide content is sent to ash tank at 55% (wt%), through with settling tank once washing liquid ( The caustic concentration of the solution is mixed and stirred at 50g / L), and it is configured into a calcium carbide slag slurry with an effective calcium oxide content of 50g / L;

[0021] (2) The calcium carbide slag slurry is pumped to the buffer tank through the slurry pump. Part of the calcium carbide slag milk in the buffer tank is sent to the raw material grinding process through the buffer pump, and the other part is sent to the fine filtration process of the crude liquid after the sedimentation red mud is separated. filter aid;

[0022] (3) After causticizing the milk of lime and mixing it with lye, the crushed ...

Embodiment 2

[0026] The process of using calcium carbide slag instead of lime for Bayer process alumina production includes the following steps:

[0027] (1) The waste carbide slag of PVC produced by the chemical plant, with a moisture content of 40% (wt%) and an effective calcium oxide content of 60% (wt%), is sent to the ash tank, mixed with hot water, and configured Form calcium carbide slag slurry with an effective calcium oxide content of 300g / L;

[0028] (2) The calcium carbide slag slurry is pumped to the buffer tank through the slurry pump. Part of the calcium carbide slag milk in the buffer tank is sent to the raw material grinding process through the buffer pump, and the other part is sent to the fine filtration process of the crude liquid after the sedimentation red mud is separated. filter aid;

[0029] (3) After causticizing the milk of lime and mixing it with lye, the crushed ore and calcium carbide slag milk are put into the raw material mill for wet grinding. The amount of...

Embodiment 3

[0033] The process of using calcium carbide slag instead of lime for Bayer process alumina production includes the following steps:

[0034] (1) The waste carbide slag of PVC produced by the chemical plant, with a moisture content of 30% (wt%) and an effective calcium oxide content of 60% (wt%), is sent to the ash tank, through the secondary washing with the settling tank (the caustic alkali concentration of solution is at 100g / L) mixing and stirring, is configured into the calcium carbide slag slurry of effective calcium oxide content 150g / L;

[0035] (2) The calcium carbide slag slurry is pumped to the buffer tank through the slurry pump. Part of the calcium carbide slag milk in the buffer tank is sent to the raw material grinding process through the buffer pump, and the other part is sent to the fine filtration process of the crude liquid after the sedimentation red mud is separated. filter aid;

[0036] (3) After causticizing the milk of lime and mixing it with lye, the c...

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 discloses a process for Bayer process aluminum oxide production by replacing carbide slag with lime, belonging to the technical field of solid waste treatment. Waste-carbide slag of a chemical plant is prepared into carbide slag emulsion with a certain effective calcium content through mixing and stirring with settled washing liquor or hot water, the prepared carbide slag emulsion is pumped to enter grinding, fine filtration and relative processes of raw materials in the Bayer process aluminum oxide production for fully playing a role of effective calcium. The carbide slag is replaced with the lime without influencing the aluminum oxide normal production or damaging the properties of sodium aluminate, the carbide slag can be used as a substitute of the lime to eliminate the influence of titanium dioxide in the ore on the dissolving-out; the addition of the carbide slag applied to the fine filtration procedure is basically equal to the addition of the lime, the indexes accord with the production requirement without influencing the filtering capacity of a leaf filter, thereby greatly reducing the raw material consumption during the Bayer process aluminum oxide production, and solving the problem of difficult carbide slag storage. The process accords with the circular economy standard advocated by our country, embodies the development of circular economy, and realizes the waste reclamation and the environment protection.

Description

Technical field: [0001] The invention relates to a solid waste treatment technology, in particular to a treatment process for chemical plant waste calcium carbide slag. Background technique: [0002] As an important chemical raw material, calcium carbide is widely used in the production of PVC, vinylon, lime nitrogen, dicyandiamide, carbon black, dissolved acetylene and other products. The storage of calcium carbide slag, the waste produced by chemical plants, not only occupies land and costs a lot, but also if the anti-seepage and dust-proof treatment is not good, it will cause serious adverse effects on the surrounding environment, especially the groundwater and surrounding villages, which is a major safety hazard in chemical production Therefore, the storage of carbide slag has always been a difficult problem for chemical plants, and how to recycle it is imminent. Invention content: [0003] The purpose of the present invention is to provide a technology for the produc...

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): C01F7/02B09B3/00
Inventor 贾启张刚潘士刚白东林邹玉国
Owner CHIPING XINFA HUAYU ALUMINA
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