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

Aluminum alloy powder spraying pretreatment chromizing line cleaning water reverse series water saving configuration

A reverse series, aluminum alloy technology, applied in the field of aluminum alloy processing, can solve the problems of insufficient nitric acid concentration, insufficient hydrofluoric acid etching ability, affecting the etching ability of oil removal tank, etc.

Active Publication Date: 2021-04-23
熊映明
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Production operation shows that nitric acid (68wt.%) 40-60g / L and hydrofluoric acid (50wt.%) 5-15g / L are selected for the degreasing tank, and the degreasing tank and water washing tank are very stable. At the same time, the dissolution characteristics of nitric acid inhibit the precipitation of fluoride, keep the degreasing tank and water washing tank clear, do not decompose, and do not precipitate; The etching ability of hydrofluoric acid is not enough, which seriously affects the etching ability of the oil removal tank; the chromic anhydride CrO is used for the chromizing tank 3 2.5-3.5g / L, hydrofluoric acid (50wt.%) 0.4-0.8g / L, nitric acid (68wt.%) 5-7g / L, nitric acid participates in the oxidation of trivalent chromium to hexavalent chromium, and decomposes and separates out carbon dioxide Nitrogen, it is easy to cause insufficient concentration of nitric acid, and the chromizing tank is prone to precipitate aluminum fluoride and chromium fluoride; these problems will become more prominent after the zero discharge of cleaning water is configured

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
  • Aluminum alloy powder spraying pretreatment chromizing line cleaning water reverse series water saving configuration
  • Aluminum alloy powder spraying pretreatment chromizing line cleaning water reverse series water saving configuration
  • Aluminum alloy powder spraying pretreatment chromizing line cleaning water reverse series water saving configuration

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0138] Aluminum alloy powder spraying pretreatment chromization line cleaning water reverse series water-saving configuration, including: 1# degreasing tank, 2# flowing water washing tank, 3# flowing water washing tank, 4# chromizing tank, 5# flowing water washing tank, 6 #Flowing washing tank, 7# draining tank, water inlet and outlet;

[0139] The 6# flowing washing tank, the 5# flowing washing tank, the 3# flowing washing tank and the 2# flowing washing tank are reversely connected in series, and the cleaning water passes through the 6# flowing washing tank, the 5# flowing washing tank, and the 3# flowing washing tank Flow in reverse series with 2# flowing washing tank; the 7# draining tank and the 6# flowing washing tank are connected by pump 1; 2# flowing washing tank, 3# flowing washing tank, 5# flowing washing tank, 6 #Flowing water washing tank is washed with tap water for 60 seconds and dripped for 30 seconds for production.

[0140] 1# degreasing tank control indicat...

Embodiment 2

[0151] The 2# flowing washing tank, the 3# flowing washing tank, the 5# flowing washing tank, and the 6# flowing washing tank are washed with tap water for 60 seconds and dripped for 30 seconds for production.

[0152] 1# degreasing tank control indicators are:

[0153] HF (50wt.%) 18g / L, PBTCA (50wt.%) 6g / L;

[0154] Time: 4 minutes;

[0155] The temperature is normal temperature;

[0156] The control index of 4# chromizing tank is:

[0157] Hydrofluoric acid (50wt.%) 0.75g / L, chromic anhydride 3.0g / L, PBTCA 3.0g / L;

[0158] Chromizing time: 150 seconds;

[0159] The temperature is normal temperature;

[0160] pH: 2.0;

[0161] Production is carried out according to the above control indicators, and the sprayed materials can meet the national standard testing requirements. Increase the PBTCA concentration of 4# chromizing tank to 4.0g / L, 4# chromizing tank, 5# flowing water washing tank, and 6# flowing water washing tank are clearer, and the spraying material is qualif...

Embodiment 3

[0163] The 2# flowing washing tank, the 3# flowing washing tank, the 5# flowing washing tank, and the 6# flowing washing tank are washed with tap water for 60 seconds and dripped for 30 seconds for production.

[0164] 1# degreasing tank control indicators are:

[0165] HF (50wt.%) 18g / L, PBTCA (50wt.%) 6g / L;

[0166] Time: 4 minutes;

[0167] The temperature is normal temperature;

[0168] The control index of 4# chromizing tank is:

[0169] Hydrofluoric acid (50wt.%) 0.75g / L, chromic anhydride 3.0g / L, PBTCA 3.0g / L;

[0170] Chromizing time: 150 seconds;

[0171] The temperature is normal temperature;

[0172] pH: 2.0;

[0173] Production is carried out according to the above control indicators, and the sprayed materials can meet the national standard testing requirements. Increase the chromizing time of 4# chromizing tank to 240 seconds, and the national standard test is qualified; reduce the chromating time of 4# chromizing tank to 50 seconds, and occasionally fail t...

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
concentrationaaaaaaaaaa
concentrationaaaaaaaaaa
Login to View More

Abstract

Aluminum alloy powder spraying pretreatment chromization line cleaning water reverse series water-saving configuration, 6# tank, 5# tank, 3# tank, 2# tank reversely connected in series, cleaning water passes through 6# tank→5# tank→3# Tank → 2# tank flows reversely in series; 1# tank contains hydrofluoric acid and phosphonobutane tricarboxylic acid; 4# tank contains hydrofluoric acid, phosphonobutane tricarboxylic acid and chromic anhydride. The present invention uses the unique design of 1# degreasing tank to be compatible with 4# chromizing tank reagents and the chemical properties of PBTCA with super strong chelating ability to chelate all metal cations and keep 1# tank→7# tank from turbidity and precipitation. The two sets of cleaning water are reversely connected in series, the cleaning water is reduced by half, the amount of chromium-containing wastewater is greatly reduced, the traditional pure water cleaning is abandoned, and the production and environmental protection costs are greatly reduced.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy processing, in particular to a reverse series water-saving arrangement of cleaning water for aluminum alloy powder spraying pretreatment chromization lines. Background technique [0002] Chromium-containing wastewater is generated after spraying chromization pretreatment. Chromium belongs to the first class of pollutants, and the wastewater must be collected and treated separately, and the wastewater can only be discharged when it meets the standard. Wastewater containing hexavalent chromium is generally treated by redox method, that is, using ferrous sulfate, sodium pyrosulfite and other reducing agents to reduce Cr in wastewater to 6+ reduced to Cr 3+ , then adjust the pH of the wastewater to 7-8, add alkali and flocculant to make Cr 3+ Form Cr(OH) 3 Precipitation, chromium hydroxide (trivalent chromium) chromium slag is formed through flocculation, sedimentation, and pressure filtrati...

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): C23C22/27C23C22/73
CPCC23C22/27C23C22/73
Inventor 熊映明
Owner 熊映明