A method for removing and recovering copper from magnesium ammonium phosphate sludge

A technology for removing copper from magnesium ammonium phosphate, which is applied to the improvement of process efficiency, photographic process, instruments, etc., can solve the problems of high processing cost, incomplete copper removal, residues, etc., so as to simplify the process flow, save the cost of chemicals, reduce the cost effect

Active Publication Date: 2018-06-26
NANJING UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the limited effect of the front-end treatment, the removal of copper in the iron scrap reduction process is not complete, and there is still copper residue before entering the ammonium magnesium phosphate precipitation process. During the crystallization process, copper is co-precipitated with ammonium magnesium phosphate, resulting in excessive copper in the sludge and becoming solid waste. Cannot be directly applied to farmland as fertilizer
The other is to directly conduct ammonium magnesium phosphate precipitation reaction on wastewater containing high concentrations of heavy metals without front-end treatment. The difficulty lies in the high cost of treatment and the ineffective reuse of sludge
If some scholars use magnesium ammonium phosphate precipitation —Pyrolytic deammonization—acid dissolution—electrodeposition process to treat cuproammonia wastewater and recover copper. The sedimentation sludge classification process is complicated and requires high temperature pyrolysis

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
  • A method for removing and recovering copper from magnesium ammonium phosphate sludge
  • A method for removing and recovering copper from magnesium ammonium phosphate sludge
  • A method for removing and recovering copper from magnesium ammonium phosphate sludge

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] For wastewater with a copper content of 20 mg / L and an ammonia nitrogen content of 333 mg / L, add phosphate and magnesium salt in a ratio of n(N):n(P):n(Mg)=1:1:1, and use sodium hydroxide Adjust the pH value to 9.5 to react magnesium ammonium phosphate, stir for 1 hour, and filter to obtain a precipitate. After testing, the copper content in the precipitate was 2920mg / kg. It is 6 times the limit value of copper in the "Standards for the Control of Pollutants in Agricultural Sludge" (GB4282-84). Add ammonium carbonate to 8-12mol / L concentrated ammonia water to prepare ammonia immersion solution, and control the molar ratio of ammonium salt to ammonia water to be (0.5-2):1. The ammonia immersion solution was mixed with the magnesium ammonium phosphate precipitation, the liquid-solid ratio was 18:1, and oscillated and leached in a closed container. After 2 hours, it was taken out and filtered. The copper content in the magnesium ammonium phosphate sludge after ammonia lea...

Embodiment 2

[0038]For wastewater with a copper content of 100 mg / L and an ammonia nitrogen content of 333 mg / L, add phosphate and magnesium salt in a ratio of n(N):n(P):n(Mg)=1:1:1, and use sodium hydroxide The pH value was adjusted to 9.5 for ammonium magnesium phosphate reaction, stirred for 1 hour, and filtered to obtain a precipitate. After testing, the copper content in the precipitate was 17849mg / kg. It is 18 times the limit value of copper in the "Standards for the Control of Pollutants in Agricultural Sludge" (GB4282-84). Add ammonium sulfate to 8-12mol / L concentrated ammonia water to prepare ammonia immersion solution, and control the molar ratio of ammonium salt to ammonia water to be (0.5-2):1. The ammonia immersion solution was mixed with the magnesium ammonium phosphate precipitation, and the liquid-solid ratio was 16:1. The liquid-solid ratio was 16:1, and the vibration leaching was carried out in a closed container. After 2 hours, it was taken out and filtered. The copper ...

Embodiment 3

[0040] For wastewater with a copper content of 100mg / L and a phosphorus content of 737mg / L, add phosphate and magnesium salt in a ratio of n(N):n(P):n(Mg)=1:1:1, and use sodium hydroxide to Adjust the pH to 10 for ammonium magnesium phosphate reaction, stir for 1 h, and filter to obtain a precipitate. After testing, the copper content in the precipitate was 17602mg / kg. It is 35 times the limit value of copper in the "Standards for the Control of Pollutants in Agricultural Sludge" (GB4282-84). Add ammonium carbonate to 8-12mol / L concentrated ammonia water to prepare ammonia immersion solution, and control the molar ratio of ammonium salt to ammonia water to be (0.5-2):1. Mix the ammonia immersion solution with the magnesium ammonium phosphate precipitation, the liquid-solid ratio is 10:1, shake and leaching in a closed container, take it out and filter after 2 hours, the copper content in the precipitation is measured to be 410mg / L. The copper content in the treated magnesium...

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 method for removing and recycling copper from magnesium ammonium phosphate sludge and belongs to the field of urban living wastewater and industrial wastewater treatment and recycling. The heavy metal content of obtained magnesium ammonium phosphate sludge exceeds the standard due to low-concentration heavy metal in wastewater. In order to directly apply magnesium ammonium phosphate sludge to a farmland as a fertilizer, the method comprises the following steps: adding concentrated ammonia water and ammonium salt into the magnesium ammonium phosphate sludge comprising copper, mixing in a vibration manner, carrying out vacuum filtration after fully reacting, drying filter residues in the shade so as to obtain purified magnesium ammonium phosphate, carrying out electrolysis on filtrate which is obtained after solid-liquid separation, recycling elementary copper, mixing electrolyte with the magnesium ammonium phosphate containing copper, and realizing recycling. The copper content of the magnesium ammonium phosphate sludge treated by the method meets Control Standards for Pollutants in Agricultural Sludge (GB4282-84). The technology is simple and easy to operate. The problem that the quality of the magnesium ammonium phosphate sludge is reduced due to the existence of the copper in the wastewater is solved. The copper also can be recycled in the elementary form after being separated. Ammonia leach liquor can be recycled, and chemical cost is saved.

Description

technical field [0001] The invention belongs to the field of urban domestic sewage and industrial wastewater treatment and resource utilization, and more specifically relates to a method for removing copper from copper-containing ammonium magnesium phosphate sludge. Background technique [0002] Direct discharge of nitrogen-containing and phosphorus-containing wastewater to natural water bodies will lead to eutrophication of water bodies. The national "13th Five-Year Plan" has clearly stated the goal of basically eliminating inferior V water bodies in key river basins. Ammonia nitrogen is an important indicator for surface water monitoring. It is imperative to limit discharge and control of phosphorus and phosphorus. Phosphorus resources with non-renewable characteristics, it is estimated that its reserves can only sustain human development for about 100 years. Magnesium ammonium phosphate crystallization technology (MAP) removes nitrogen and phosphorus in wastewater by prec...

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): C22B7/00C25C1/12
CPCC22B7/008C25C1/12Y02P10/20
Inventor 任洪强黄道端丁丽丽梁潇
Owner NANJING UNIV
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