Reutilization method of chromium-containing leather production sludge

A technology of chromium sludge and chromium slurry, which is applied in the fields of sludge treatment, chemical instruments and methods, water/sludge/sewage treatment, etc. with thorough effect

Active Publication Date: 2012-02-29
BROTHER ENTERPRISES HLDG CO LTD
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The present invention aims at the deficiencies of the above-mentioned prior art, combined with the existing tannery chromium-containing sludge recycling scheme, while the filtrate is reused to prepare chrome tanning agent, th

Method used

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  • Reutilization method of chromium-containing leather production sludge
  • Reutilization method of chromium-containing leather production sludge

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] Put 2000kg of chromium-containing sludge from tannery into 680kg of dilute sulfuric acid with a concentration of 55% for dissolution, then slowly heat up to 80-90°C and stir for 4 hours to hydrolyze, cool down to 30-40°C, and filter through plate and frame to obtain filtrate 2620kg and filter residue 60kg.

[0024] Put 280kg of red alum sodium into the obtained 2620kg of filtrate, then slowly raise the temperature to 90-100°C, and keep stirring at 90-100°C for 2 hours. After the heat preservation is completed, drop the temperature to 80-85°C and add dropwise Add 140kg of starch sugar aqueous solution, drop it for about 1 hour, reduce hexavalent chromium to trivalent chromium, keep stirring at 95-100°C for 1 hour after dropping, check and control the residual amount of hexavalent chromium to not exceed 2mg / kg, Then lower the temperature to 40-60°C to obtain 3000kg of chrome slurry solution.

[0025] Take 2640kg of chrome slurry solution and carry out spray drying betwee...

Embodiment 2

[0029] Put 2000kg of chromium-containing sludge from tannery into 1000kg of dilute sulfuric acid with a concentration of 55% for dissolution, then slowly raise the temperature to 70-80°C and stir for 3 hours to hydrolyze, cool down to 40-50°C and filter through plate and frame to obtain the filtrate 2940kg and filter residue 60kg.

[0030] Put 350kg of red alum sodium into the obtained 2940kg filtrate, then slowly raise the temperature to 90-100°C, and keep stirring at 90-100°C for 2 hours. After the heat preservation is completed, drop the temperature to 80-85°C and add dropwise Add 170kg of starch sugar aqueous solution, drop it for about 1 hour, reduce hexavalent chromium to trivalent chromium, keep stirring at 95-100°C for 1 hour after dropping, check and control the residual amount of hexavalent chromium to not exceed 2mg / kg, Then lower the temperature to 40-60°C to obtain about 3460kg of chrome slurry solution.

[0031] Take 2660kg of chrome slurry solution and spray-dr...

Embodiment 3

[0035] Put 2000kg of chromium-containing sludge from tannery into 2000kg of dilute sulfuric acid with a concentration of 55% for dissolution, then slowly raise the temperature to 60-70°C, stir and hydrolyze for 3 hours, cool down to 40-50°C, and filter through plate and frame to obtain the filtrate 3940kg and filter residue 60kg.

[0036] Put 900kg of sodium red alum into the obtained 3940kg filtrate, then slowly raise the temperature to 90-100°C, keep stirring at 90-100°C for 2 hours, drop the temperature at 80-85°C after the heat preservation is completed, and add 50% of the mass content dropwise Starch sugar aqueous solution 450kg, add dropwise for about 1 hour, reduce hexavalent chromium to trivalent chromium, keep stirring at 95-100°C for 1 hour after dropwise addition, check and control the residual amount of hexavalent chromium to not exceed 2mg / kg, Then lower the temperature to 40-60°C to obtain about 5290kg of chrome slurry solution.

[0037] Take 4290kg of chrome sl...

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Abstract

The invention relates to a reutilization method of chromium-containing leather production sludge. The method comprises steps that: the chromium-containing leather production sludge is dissolved by using acid, and is hydrolyzed; the obtained material is filtered, and a filtrate is used for producing a chrome tanning agent; the filter residue is used for producing a chromium-containing retanning agent, such that a secondary environmental pollution problem caused by filter residue produced during the reutilization of the chromium-containing leather production sludge is completely solved. When the filtrate is used for producing the chrome tanning agent, a powdery chrome tanning agent is produced.

Description

technical field [0001] The invention belongs to a clean production technology in the tanning industry, in particular to a method for reusing chromium-containing sludge in tanning, so as to completely solve the problem of environmental pollution caused by sludge produced in the tanning production process. Background technique [0002] The sludge produced in the leather production process has caused serious pollution to the environment. At present, the existing tannery chromium-containing sludge recovery and utilization schemes are all dissolved in acid, filtered, and the filtrate is formulated into chrome tanning agent for tanning, but the filtered residue is not treated. The main components of the filter residue are dander hydrolysis residue and inorganic salt precipitates, which are still chromium-containing solid waste, and will cause secondary pollution to the environment if not recycled. Eliminating the secondary pollution of filter residues, realizing the utilizati...

Claims

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Application Information

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IPC IPC(8): C14C3/02C02F11/00
Inventor 周中平张文
Owner BROTHER ENTERPRISES HLDG CO LTD
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