Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Iron and Steel Pickling Wastewater Recycling and Zero Discharge Process

A technology for pickling and recycling iron and steel, applied in the field of water treatment, can solve the problems of lowering the pH value of water body, large amount of residues, difficult treatment, etc., and achieve the effect of increasing Fe content

Active Publication Date: 2015-10-28
DONGGUAN SANRENXING ENVIRONMENTAL TECH CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

If steel pickling wastewater is improperly treated and discharged into the water body, it will cause the following pollution: 1. Lower the pH value of the water body, causing aquatic plants, algae, and fish to die
2. Fe 2+ Form colloidal Fe(OH) in water 2 , Fe(OH) 3 , but under the hydraulic conditions of the river channel, floc precipitation cannot be formed, but it forms yellow-gray and black colloidal pollution belts with organic sulfur and humic acid in the river channel water, which is extremely poor in appearance
3. The organic chemicals that constitute COD are surfactants, phosphates, and lubricating oils, and the eutrophication of water bodies is irreversible.
[0008] ① High cost: In theory, to neutralize wastewater with a pH value of 2 to a pH value of 7, the alkali consumption per ton of water is 1.5kg NaOH, and some lime is used to replace NaOH, plus power consumption and manual depreciation, the treatment cost is 4.5 yuan / tons of water
[0010] ③COD is not up to standard
This shows that COD in this type of wastewater is soluble and cannot be separated and removed by neutralization and precipitation; it also shows that Fe(OH) 2 Colloidal flocs have extremely poor adsorption to such COD substances (surfactants, organic phosphates, lubricants, etc.)
[0011] ④The amount of residue is extremely large and extremely difficult to handle
[0012] ⑤ Drainage cannot be reused directly
Even if 50% of the water is reused, the TDS in the system will reach 10000mg / L and the COD will reach 1000mg / L in a few days, and the reclaimed water reuse system will not work normally

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
  • Iron and Steel Pickling Wastewater Recycling and Zero Discharge Process
  • Iron and Steel Pickling Wastewater Recycling and Zero Discharge Process
  • Iron and Steel Pickling Wastewater Recycling and Zero Discharge Process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] Such as figure 1 Shown, steel pickling wastewater recycling and zero discharge process, it includes the following process steps:

[0040] (a) Iron and steel pickling wastewater inflow;

[0041] (b) The iron and steel pickling wastewater is subjected to Fenton reaction, so that the COD of the iron and steel pickling wastewater is reduced to ≤60mg / L, and Fe 2+ Convert to Fe 3+ , TDS (total dissolved solids) down to ≤2000mg / L; the H 2 o 2 or O 3 Add to Fenton reactor for Fenton reaction, or use titanium ruthenium electrode Ti-RuO 2 Carry out Fenton reaction;

[0042] (c) Iron and steel pickling wastewater is subjected to FeC micro-electrolytic reduction reaction; after the FeC micro-electrolytic reduction reaction, the pH of the steel pickling wastewater is more than 3.5;

[0043] (d) Neutralization and flocculation: add NaOH and PAM to carry out neutralization and flocculation reaction; after neutralization and flocculation, the pH of steel pickling wastewater is m...

Embodiment 2

[0062] Such as figure 2 As shown, the difference between the present embodiment and the embodiment 1 is that in the iron and steel pickling wastewater recycling and zero discharge process of the present embodiment, after the step (d) and the flocculation, the step (e) membrane module desalination Before, step (d1) thick slurry circulation is also included; step (d) and flocculated effluent enter step (d1) thick slurry circulation, step (d1) effluent of thick slurry circulation enters step (e) membrane module desalination, step ( e) The thick slurry after the desalination of the membrane module is returned to the thick slurry circulation in step (d1).

[0063] The Fe(OH) produced by step (d1) thick slurry circulation 3 The waste water purifying agent is prepared through filter press, beating, dissolving and oxidation reaction. In the process of beating and dissolving, add steel pickling wastewater; then add additives (such as additives containing rare earth elements) and air...

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

PropertyMeasurementUnit
recovery rateaaaaaaaaaa
Login to View More

Abstract

The invention belongs to the technical field of water treatment, and particularly relates to a steel pickling waste water resourcization and zero discharge process. The steel pickling waste water resourcization and zero discharge process comprises the following process steps of: (a) introducing steel pickling waste water; (b) carrying out Fenton reaction on the steel pickling waste water to reduce the COD (Chemical Oxygen Demand) of the steel pickling waste water to be less than or equal to 60 mg / L, convert Fe<2+> into Fe<3+> and reduce TDS (Total Dissolved Solids) to be less than or equal to 2000 mg / L; (c) carrying out FeC microelectrolysis reduction reaction on the steel pickling waste water; (d) carrying out neutralization flocculation; (e) desalting a membrane assembly to reduce the TDS of the steel pickling waste water to be less than or equal to 200 mg / L; (f) recycling effluent water. The steel pickling waste water resourcization and zero discharge process disclosed by the invention realizes the cleaning production, realizes the resourcization utilization of waste water, waste acid and iron mud, generates the benefit and realizes the zero discharge.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and in particular relates to resource utilization and zero discharge process of steel pickling wastewater. Background technique [0002] Iron and steel pickling wastewater includes waste acid and wastewater. Wherein the waste acid accounts for 2-3% of the total water, and the pollution index of the waste water is shown in the following table: [0003] [0004] . If steel pickling wastewater is improperly treated and discharged into the water body, it will cause the following pollution: 1. Lower the pH value of the water body, resulting in the death of aquatic plants, algae, and fish. 2. Fe 2+ Form colloidal Fe(OH) in water 2 , Fe(OH) 3 , but under the hydraulic conditions of the river channel, floc precipitation cannot be formed, but it forms a yellow-gray and black colloidal pollution belt with organic sulfur and humic acid in the river channel water, which has a very poor sensor...

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): C02F9/06C02F9/08
Inventor 焦伟丽袁伟光曾庆波赵锐柏
Owner DONGGUAN SANRENXING ENVIRONMENTAL TECH CO LTD
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
Eureka Blog
Learn More
PatSnap group products