Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for preparing magnesium sulphate heptahydrate by laterite-nickel ore acid leaching nickel immersing waste water

A technology of magnesium sulfate heptahydrate and laterite nickel ore, applied in directions such as magnesium sulfate, can solve the problems such as no reports on the recovery of magnesium sulfate from nickel precipitation wastewater, large amount of lime, not meeting the requirements for direct discharge of industrial wastewater, etc., and achieves mild operating conditions. , Simple operation, the effect of increasing the concentration

Inactive Publication Date: 2014-11-05
KUNMING UNIV OF SCI & TECH
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, the nickel precipitation wastewater is neutralized by lime and discharged directly, but there are two problems: first, the lime consumption is large, and every m 3 The amount of lime added to the wastewater is 120-150kg; second, the wastewater still contains a large amount of sodium salt, which does not meet the requirements for direct discharge of industrial wastewater
Comprehensive invention patent search, no report on recovery of magnesium sulfate from nickel precipitation wastewater

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
  • Method for preparing magnesium sulphate heptahydrate by laterite-nickel ore acid leaching nickel immersing waste water

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] Embodiment 1: The method for preparing magnesium sulfate heptahydrate by acid leaching nickel wastewater of laterite nickel ore in this embodiment is as follows:

[0037] (1) Take 1000 mL of sulfurized nickel precipitation wastewater from the acid leaching solution of laterite nickel ore. After testing, its pH value is 2.3, its magnesium ion concentration is 20528.35mg / L, sodium ion concentration is 1731.20mg / L, and ferrous ion concentration is 1121.12 mg / L, the concentration of aluminum ion is 977.57 mg / L, and the concentration of other metal ions is less than 20 mg / L. Air was introduced under stirring conditions, and magnesite was added. When the pH value of the solution reached 5.6, the feeding was stopped and the reaction was continued for 2 hours. After testing, the end pH value was 6.0. After filtration and separation, 967 mL of magnesium-rich liquid was obtained. After analysis, the magnesium ion concentration was 25467.37 mg / L and the aluminum ion concentration was...

Embodiment 2

[0039] Embodiment 2: The method for preparing magnesium sulfate heptahydrate by acid leaching nickel wastewater of laterite nickel ore in this embodiment is as follows:

[0040] (1) Take 1000mL of sulfurized nickel precipitation wastewater from the acid leaching solution of laterite nickel ore. After testing, its pH value is 2.5, its magnesium ion concentration is 21437.20mg / L, sodium ion concentration is 1943.12mg / L, and ferrous ion concentration is 1023.32 mg / L, the concentration of aluminum ion is 737.42mg / L, and the concentration of other metal ions is less than 15mg / L. Air was introduced under stirring conditions, the air volume was 70 mL / min, and magnesite was added intermittently. When the pH value of the solution reached 6.12, the feeding was stopped and the reaction was continued for 2 hours. After testing, the end pH value was 6.5. After filtration and separation, 962 mL of magnesium-rich liquid was obtained. After analysis, the magnesium ion concentration was 23234.20 ...

Embodiment 3

[0042] Embodiment 3: The method for preparing magnesium sulfate heptahydrate by acid leaching nickel wastewater of laterite nickel ore in this embodiment is as follows:

[0043] (1) Take 1000mL of sulfurized nickel precipitation wastewater from the acid leaching solution of laterite nickel ore. After testing, its pH value is 2.32, its magnesium ion concentration is 20975.32mg / L, sodium ion concentration is 1877.42mg / L, and ferrous ion concentration is 1043.25 mg / L, the concentration of aluminum ion is 645.39mg / L, and the concentration of other metal ions is less than 20mg / L. Air was passed through under stirring conditions, the air volume was 60 mL / min, and magnesite was added intermittently. When the pH value of the solution reached 5.9, the feeding was stopped and the reaction was continued for 2 hours. After testing, the end pH was 6.27. After filtration and separation, 972 mL of magnesium-rich liquid was obtained. After analysis, the magnesium ion concentration was 24123.20 m...

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 relates to a method for preparing magnesium sulphate heptahydrate by laterite-nickel ore acid leaching nickel immersing waste water and belongs to the technical fields of waste utilization and environmental science. The method provided by the invention comprises the following steps of: adding magnesite into a laterite-nickel ore acid leaching waste solution and introducing the air, adjusting pH value to be 6.0-6.5 to remove iron and aluminium with enriched magnesium, then adjusting pH value to be 8.0-8.5 with lime milk to remove impurities such as nickel, lead, chromium and the like, so as to realize purification on nickel waste water, and finally carrying out concentration, fractional crystallization and vacuum drying to obtain a magnesium sulphate heptahydrate product with the purity more than 99%. According to the method provided by the invention, magnesium ion concentration in a solution is improved by virtue of a double salt reaction between magnesite powder and nickel immersing waste water, and separation of ions easy to hydrolyze such as aluminium ions and iron ions is achieved, so that originality is achieved; and primary magnesium enrichment purification and then treatment with lime are carried out, and deep purification is achieved, so that quality of a magnesium sulphate product is guaranteed.

Description

technical field [0001] The invention relates to a method for preparing magnesium sulfate heptahydrate from laterite nickel ore acid leaching nickel wastewater, and belongs to the field of waste utilization and environmental science and technology. Background technique [0002] The acid leaching nickel wastewater of laterite nickel ore uses laterite nickel ore as raw material, and adopts low-grade laterite nickel ore "mining-ore-making-heap leaching (stirring leaching)-sulfide nickel precipitation-nickel sulfide concentrate high-efficiency oxygen pressure leaching-purification-extraction -The pressurized acid leaching process of "electrowinning to produce electrolytic nickel" produces the sulfide nickel precipitation wastewater of metal nickel, and discharges 200-250m of raffinate per ton of metal nickel 3 , and the raffinate is acidic, its pH value is between 3.0 and 3.5, it contains a large amount of magnesium ions and a certain amount of heavy metal ions, and they all exis...

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 Patents(China)
IPC IPC(8): C01F5/40
Inventor 夏举佩张召述晁静霞
Owner KUNMING UNIV OF SCI & TECH