Method for treating metallurgical wastewater by nanofiltration-freezing denitration process

A technology of freezing denitrification and nanofiltration, applied in metallurgical wastewater treatment, frozen water/sewage treatment, sedimentation treatment, etc., to achieve the effect of saving industrial water, low energy consumption, and simple process

Inactive Publication Date: 2019-03-01
LANZHOU UNIVERSITY OF TECHNOLOGY
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, in the case that the existing single treatment technology for metallurgical wastewater cannot treat wastewater efficiently, energy-saving, and environmentally friendly, the coupling process of membrane technology with low cost and low energy consumption will be an inevitable trend

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 treating metallurgical wastewater by nanofiltration-freezing denitration process
  • Method for treating metallurgical wastewater by nanofiltration-freezing denitration process
  • Method for treating metallurgical wastewater by nanofiltration-freezing denitration process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] (1) Pretreatment

[0035] Pipeline the untreated metallurgical wastewater into the reaction pool, add 14.5t of hydrochloric acid with a mass fraction of 20% to the reaction pool every hour, and continue to add hydrochloric acid to adjust the pH of the metallurgical wastewater to 6~7 after fully reacting.

[0036] (2) Ultrafiltration

[0037] The PH-adjusted metallurgical wastewater is sent to the ultrafiltration system through the pipeline, and the large particles of impurities are intercepted, and the ultrafiltration permeate enters the nanofiltration system.

[0038] (3) Nanofiltration

[0039] The nanofiltration membrane module can be commonly used in the market, and the D series produced by GE is preferred. The obtained ultrafiltration permeate enters the nanofiltration membrane module through a booster pump at 3.5Mpa, and the temperature of the feed liquid is 25°C. After being processed by the nanofiltration system, the obtained nanofiltration permeate mainly con...

Embodiment 2

[0048] (1) Pretreatment

[0049] Pipeline the untreated metallurgical wastewater into the reaction pool, add 11.6t of hydrochloric acid with a mass fraction of 25% to the reaction pool every hour, and continue to add hydrochloric acid to adjust the pH of the metallurgical wastewater to 6~7 after the reaction is complete.

[0050] (2) Ultrafiltration

[0051] The PH-adjusted metallurgical wastewater is sent to the ultrafiltration system through the pipeline, and the large particles of impurities are intercepted, and the ultrafiltration permeate enters the nanofiltration system.

[0052] (3) Nanofiltration

[0053] The nanofiltration membrane module can be commonly used in the market, and the D series produced by GE is preferred. The obtained ultrafiltration permeate enters the nanofiltration membrane module through the booster pump at 3.5Mpa, and the temperature of the feed liquid is 25°C. After being treated by the nanofiltration system, the obtained nanofiltration permeate ...

Embodiment 3

[0062] (1) Pretreatment

[0063] Pipeline the untreated metallurgical wastewater into the reaction pool, add 9.7t of hydrochloric acid with a mass fraction of 30% to the reaction pool every hour, and continue to add hydrochloric acid to adjust the pH of the metallurgical wastewater to 6~7 after the reaction is complete.

[0064] (2) Ultrafiltration

[0065] The PH-adjusted metallurgical wastewater is sent to the ultrafiltration system through the pipeline, and the large particles of impurities are intercepted, and the ultrafiltration permeate enters the nanofiltration system.

[0066] (3) Nanofiltration

[0067] The nanofiltration membrane module can be commonly used in the market, and the D series produced by GE is preferred. The obtained ultrafiltration permeate enters the nanofiltration membrane module through a booster pump at 3.5Mpa, and the temperature of the feed liquid is 25°C. After being processed by the nanofiltration system, the obtained nanofiltration permeate 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 discloses a method for treating metallurgical wastewater by a nanofiltration-freezing denitration process. The method comprises the steps of feeding untreated metallurgical wastewater into a reaction tank through a pipeline and adding HCl in the reaction tank to remove HCO3- and CO32- from the metallurgical wastewater; after the reaction, treating the metallurgical wastewater throughan ultrafiltration system and a nanofiltration system sequentially, and delivering the obtained nanofiltration concentrate to a freezing denitration system through the pipeline for freezing denitration treatment; introducing the concentrate subjected to the freezing denitration treatment to a centrifugation separation section to separate generated sodium sulfate crystals, and making a small amount of the solution generated by centrifugation separation return to the ultrafiltration system for reuse; introducing the obtained nanofiltration permeate to a salt pool through the pipeline, and adding a certain amount of chlorine to prepare caustic soda. The method has the advantages of being simple in process, low in energy consumption and capable of treating the metallurgical wastewater generated by a chemical plant economically and effectively and achieving recycling of the wastewater.

Description

technical field [0001] The invention relates to the field of wastewater treatment, in particular to a method for treating metallurgical wastewater by a nanofiltration-freeze denitrification process. Background technique [0002] Traditional wastewater treatment technologies commonly used in industry include evaporation crystallization, biological methods, and membrane separation technologies. Evaporation crystallization includes natural evaporation, multi-effect evaporation and mechanical evaporation; although natural evaporation has low energy consumption, due to the unsatisfactory solar evaporation efficiency, the water inflow is greater than the evaporation amount, the area is large, and it is seriously affected by natural factors. Efficient evaporation connects multiple evaporators in series, and uses the secondary steam generated by the previous evaporator to heat the next evaporator. Compared with natural evaporation, it has the advantages of low energy consumption and...

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): C02F9/08C01D5/00C01D1/04C02F103/16
CPCC01D1/04C01D5/00C02F1/22C02F1/38C02F1/442C02F1/444C02F9/00C02F2001/007C02F2103/16C02F2301/08
Inventor 张栋强陈彦安段润豪赵静李贵贤杨平苏鑫
Owner LANZHOU UNIVERSITY OF TECHNOLOGY
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