Method for recycling silver in high oil-bearing sludge

A technology of sludge and Zhongyin, which is applied in the field of recycling high oily sludge Zhongyin, can solve the problems of enterprise loss, long selling time, recycling, etc., and achieve the effects of reducing economic losses, improving turnover rate and high recovery rate

Inactive Publication Date: 2017-05-24
WENZHOU LONGSUN ELECTRICAL ALLOY CO LTD
View PDF14 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This viscous sludge cannot be recovered by conventional methods
At present, most enterprises choose to sell the settled and collected silt to recycling plants. However, due to the long period of time for collec

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

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0020] Example 1

[0021] Step 1. Degreasing: Take 100kg of high oily sludge and put it in the reactor, add 50kg of industrial alcohol, stir until there is no agglomeration, and perform air extraction during the stirring process, and use a plate and frame suction filter to filter until it is dry, and repeat the cleaning 2 times Afterwards, it is dried and weighed to obtain degreasing sludge;

[0022] Step 2. Reduction: Pour the weighed degreasing sludge back into the reaction kettle, add 50kg of workshop pickling wastewater, heat up to 70°C under stirring, and perform air extraction during the stirring process, slowly add 20kg atomized iron powder, and continue stirring for 2h , Use a plate and frame suction filter to filter to dryness, and wash with water to neutral;

[0023] Step 3. Oxidation and dissolution: Pour the sludge back into the reaction kettle again, add 100kg of nitric acid, keep stirring at 80°C for 2h, after cooling, suction filtration, collect the filtrate, wash the...

Example Embodiment

[0028] Example 2

[0029] Step 1. Degreasing: Take 100kg of sludge and place it in the reactor, add 50kg of acetone, stir until there is no agglomeration, draw air during the stirring process, use a plate and frame suction filter to filter to dryness, rinse with distilled water for 3 times, and bake Dry, weighed to obtain degreasing sludge;

[0030] Step 2. Reduction: Pour the weighed degreasing sludge back into the reactor, add 50kg of pickling wastewater from the workshop, heat up to 70°C under stirring, and ventilate during stirring. Slowly add 20kg of zinc powder and continue stirring for 2h. The plate and frame suction filter is sucked to dry, and washed with water to neutral;

[0031] Step 3. Oxidation and dissolution: Pour the sludge back into the reaction kettle again, add 100kg of nitric acid, keep stirring at 80°C for 2h, after cooling, suction filtration, collect the filtrate, wash the residue 3 times with distilled water, dry, and weigh;

[0032] Step 4. Re-reduction: Add...

Example Embodiment

[0036] Example 3

[0037] Step 1. Degreasing: Take 100kg of sludge into the reactor, add 50kg of acetonitrile, stir until there is no agglomeration, draw air during the stirring process, use a plate and frame suction filter to filter to dryness, rinse with distilled water for 3 times, and bake Dry, weighed to obtain degreasing sludge;

[0038] Step 2. Reduction: Pour the weighed degreasing sludge back into the reactor, add 50kg of pickling wastewater from the workshop, heat up to 70°C under stirring, and ventilate during stirring. Slowly add 20kg of zinc powder and continue stirring for 2h. The plate and frame suction filter is sucked to dry, and washed with water to neutral;

[0039] Step 3. Oxidation and dissolution: Pour the sludge back into the reactor again, add 100kg of nitric acid (1+1), keep at 80℃ and stir for 2h, cool and filter with suction, collect the filtrate, rinse the residue 3 times with distilled water, dry, and weigh ;

[0040] Step 4. Re-reduction: Add 30kg of hy...

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 recycling silver in high oil-bearing sludge. The steps of oil removing, reducing, oxidizing and reducing again are adopted. Because oils, elemental silver, combined silver and the like are contained in the sludge, the oils in the high oil-bearing sludge are removed firstly to reduce the stickiness of the high oil-bearing sludge, then, a reducing agent is used for reducing the combined silver to the elemental silver, the elemental silver in the sludge is oxidized and dissolved into silver ions to enter a solution through strong acid, and drawing and filtering are conducted to obtain a silver ion containing filtrate. Finally, the silver ions are deposited from the filtrate to obtain silver chloride, and the silver chloride is reduced through the reducing agent to obtain silver powder. According to the technical scheme, the higher recycling rate can be achieved, and 97% of the silver in the high oil-bearing sludge can be recycled to obtain the silver powder with the purity being 99.8%, and therefore, the turnover rate of the silver in the sludge is improved and the economical loss caused by the cheap sale of the sludge is reduced.

Description

technical field [0001] The invention relates to the technical field of precious metal silver recovery, in particular to a method for recovering silver from high oily sludge. Background technique [0002] Silver is a commonly used precious metal, and it is used in a large amount in the electrical alloy industry. It is used in the production of various low-voltage electrical contacts every year, with thousands of tons of silver metal. From raw materials to finished products, each process has a high or low yield of materials at one time, so various silver-containing scraps will inevitably be produced. The quantity of such scraps is huge, and there are many recycling methods, most of which are relatively simple, so most processing enterprises have relatively comprehensive recycling processes. But in addition, various ground ash, debris, and a small amount of silver are discharged into the waste water pool along with the waste water during the milling and post-treatment process,...

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
IPC IPC(8): C22B7/00C22B11/00B22F9/24
CPCB22F9/24C22B7/006C22B11/046Y02P10/20
Inventor 殷彬励冯如信
Owner WENZHOU LONGSUN ELECTRICAL ALLOY 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
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