Method for recovering tungsten from waste SCR catalyst regeneration waste alkali liquor and application

A technology of SCR catalyst and waste lye, applied in the field of tungsten recovery, can solve the problems affecting metal recovery, waste of resources, and increase the difficulty of recycling tungsten elements, and achieve the effect of saving dosage and improving separation efficiency.

Active Publication Date: 2021-08-13
INST OF PROCESS ENG CHINESE ACAD OF SCI
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

During the leaching process, some valuable metals in the spent SCR denitrification catalyst will be dissolved in the leach solution, and if this part of the leach solution is directly discharged, it will cause a waste of resources
At the same time, some impurities will also be mixed into the leach solution, which will affect the recovery of valuable metals in the leach solution. For example, when recovering tungsten, the arsenic element mixed into the leach solution will increase the recovery of tungsten. Difficulty of element process and influence on recovery efficiency of tungsten element

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 recovering tungsten from waste SCR catalyst regeneration waste alkali liquor and application

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] This embodiment provides a method for recovering tungsten from spent SCR catalyst regenerated spent lye, said method comprising the following steps:

[0040] The waste lye was sampled and tested to obtain the concentrations of sodium hydroxide, tungsten, arsenic, silicon and phosphorus in the waste lye.

[0041] Take a preset volume of spent lye, evaporate and concentrate the spent lye until the mass concentration of sodium hydroxide is 20wt.%, to obtain a concentrated solution, cool down the concentrated solution, crystallize and filter, and obtain pretreated crystallization and recovery solution. Wherein, the temperature range for the crystallization and filtration of the concentrated solution is 45°C to 50°C.

[0042] Deionized water is used to fully dissolve the pretreatment crystals to obtain a pretreatment solution. Wherein, the quality of the added deionized water is 1.5 times of the quality of the pretreated crystals.

[0043] A sulfuric acid solution is added...

Embodiment 2

[0050] This embodiment provides a method for recovering tungsten from spent SCR catalyst regenerated spent lye, said method comprising the following steps:

[0051] The waste lye was sampled and tested to obtain the concentrations of sodium hydroxide, tungsten, arsenic, silicon and phosphorus in the waste lye.

[0052] Take a preset volume of spent lye, evaporate and concentrate the spent lye until the mass concentration of sodium hydroxide is 20wt.%, to obtain a concentrated solution, cool down the concentrated solution, crystallize and filter, and obtain pretreated crystallization and recovery solution. Wherein, the temperature range for cooling the concentrated solution for crystallization and filtration is 45°C to 50°C.

[0053] Deionized water is used to fully dissolve the pretreatment crystals to obtain a pretreatment solution. Wherein, the quality of the added deionized water is 3.0 times of the pretreatment crystal quality.

[0054] Sulfuric acid solution is added to...

Embodiment 3

[0061] This embodiment provides a method for recovering tungsten from spent SCR catalyst regenerated spent lye, said method comprising the following steps:

[0062] The waste lye was sampled and tested to obtain the concentrations of sodium hydroxide, tungsten, arsenic, silicon and phosphorus in the waste lye.

[0063] Take a preset volume of spent lye, evaporate and concentrate the spent lye until the mass concentration of sodium hydroxide is 20wt.%, to obtain a concentrated solution, cool down the concentrated solution, crystallize and filter, and obtain pretreated crystallization and recovery solution. Wherein, the temperature range for cooling the concentrated solution for crystallization and filtration is 45°C to 50°C.

[0064] Deionized water is used to fully dissolve the pretreatment crystals to obtain a pretreatment solution. Wherein, the quality of the added deionized water is 3.0 times of the pretreatment crystal quality.

[0065] Sulfuric acid solution is added to...

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 recovering tungsten from waste SCR catalyst regeneration waste alkali liquor and application. An evaporation concentration crystallization method is adopted to separate a tungsten element and other substances from an alkali solution, and the separation efficiency of the tungsten element and other substances is effectively improved by controlling the concentration of sodium hydroxide in the evaporation concentration process. Then, carbonate ions are removed through acid treatment, and a scheelite concentrate is obtained through the process of adding magnesium sulfate to remove impurities and adding calcium oxide to separate the tungsten element. By adopting a manner of firstly adding acid to remove the carbonate ions, the carbonate ions can be prevented from entering the next working procedure to consume magnesium sulfate; and after the contents of an arsenic element, a silicon element and a phosphorus element are counted, a sufficient amount of magnesium sulfate is added into secondary treatment liquid, so that the situation that the arsenic element is not sufficiently precipitated due to the existence of the silicon element and the phosphorus element is avoided. According to the method for recovering the tungsten, the aims that the precipitation rate of the tungsten element in the waste alkali liquor can be larger than 91%, no arsenic element is detected in the recycled product scheelite concentrate, and the content of tungsten trioxide is larger than 65% are achieved.

Description

technical field [0001] This application relates to the technical field of secondary resource utilization, in particular to a method and application for recovering tungsten from spent SCR catalyst regenerated waste lye. Background technique [0002] In coal-fired power plants, the denitrification activity of SCR catalysts for denitrification gradually decreases due to the poisoning of active components, aging and other reasons with the increase of operating time. When the activity is lower than the design deactivation threshold, it must be replaced layer by layer. At present, commercial SCR denitration catalysts are vanadium-titanium catalysts, and their main components include 80~85wt% TiO 2 , 0.5%~1wt%V 2 o 5 , 4~10wt%WO 3 , and SiO 2 、Al 2 o 3 and other structural auxiliary components. The V, W contained in the waste SCR denitration catalyst and the heavy metals such as Fe, As, Pb adsorbed during use will cause serious harm to the environment. At the same time, val...

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): C22B34/36C22B7/00
CPCC22B7/008C22B34/365Y02P10/20
Inventor 王兴瑞王晨晔李会泉
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI
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