Regeneration process and regeneration device for heavy metal containing nitric acid waste liquor

A technology for process equipment and heavy metals, which is applied to the regeneration process of nitric acid waste liquid containing heavy metals and the field of regeneration equipment, can solve the problems of low economic benefit, consumption of waste chemicals, secondary pollution, etc., and achieves no secondary pollution, high market value, The effect of low energy consumption

Inactive Publication Date: 2013-06-26
昆山市台鑫五金厂
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

It is very difficult to deal with the invalid nitric acid removal solution because it contains a large amount of total nitrogen
The treatment of nitric acid waste liquid in the industry is mainly acid-base neutralization, after sedimentation and extraction of heavy metals, and then denitrification treatment, which not only consumes a lot of chemicals, but also consumes a lot of energy, which is easy to cause secondary pollution
Other methods such as oxalic acid replacement and regeneration of nitric acid are simple in process, but the economic benefit is low

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
  • Regeneration process and regeneration device for heavy metal containing nitric acid waste liquor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0017] A heavy metal-containing nitric acid waste liquid regeneration process, under the negative pressure of 0.05 MPa, the nitric acid is first passed through the first-effect evaporation crystallization device, and the temperature of the first-effect evaporation crystallization device is controlled at 60°C, and then enters the second-effect evaporation crystallization device. The temperature of the two-effect evaporation and crystallization device is controlled at 50°C, and the nitric acid vapor is condensed and recovered to obtain regenerated nitric acid. At the same time, the heavy metal nitrate recovered from the discharge system of the evaporation and crystallization device and the mass percentage concentration are 98% concentrated sulfuric acid according to 3: 1, and stirred, while cooling to room temperature, after suction filtration, the heavy metal sulfate product was obtained.

Embodiment 2

[0019] A heavy metal-containing nitric acid waste liquid regeneration process. Under the action of negative pressure of 0.03 MPa, the nitric acid is first passed through the first-effect evaporation crystallization device, and the temperature of the first-effect evaporation crystallization device is controlled at 65°C, and then enters the second-effect evaporation crystallization device. The temperature of the two-effect evaporation and crystallization device is controlled at 40°C, and the nitric acid vapor is condensed and recovered to obtain regenerated nitric acid. At the same time, the heavy metal nitrate recovered from the discharge system of the evaporation and crystallization device and the mass percentage concentration of 95% concentrated sulfuric acid are calculated according to 1: 1, and stirred, while cooling to room temperature, after suction filtration, the heavy metal sulfate product was obtained.

Embodiment 3

[0021] A heavy metal-containing nitric acid waste liquid regeneration process, under the negative pressure of 0.07 MPa, the nitric acid is first passed through the first-effect evaporation crystallization device, and the temperature of the first-effect evaporation crystallization device is controlled at 70°C, and then enters the second-effect evaporation crystallization device, The temperature of the two-effect evaporation and crystallization device is controlled at 45°C, and the nitric acid vapor is condensed and recovered to obtain regenerated nitric acid. At the same time, the heavy metal nitrate recovered from the discharge system of the evaporation and crystallization device and the mass percentage concentration are 96% concentrated sulfuric acid according to 2: 1, and stirred, while cooling to room temperature, after suction filtration, the heavy metal sulfate product was obtained.

[0022] see figure 1 , the present invention is used for the process equipment of heavy m...

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 regeneration process and regeneration equipment for heavy metal containing nitric acid waste liquor. The regeneration process comprises the following steps of: evaporating nitric acid by virtue of an evaporative crystallization device under the action of negative pressure, condensing and recycling the nitric acid steam to obtain regenerated nitric acid; mixing heavy metal nitrate, which is recycled by a discharging system of the evaporative crystallization device, with concentrated sulfuric acid, stirring the mixture, cooling the mixture to room temperature, and filtering the mixture to obtain a heavy metal sulphate product in suction. The regeneration equipment comprises an evaporating device, a condensing and cooling device, a cooling and crystallizing device, a suction-filtering device and a horizontal ejection vacuum device, wherein the evaporating device, the condensing and cooling device and the cooling and crystallizing device are communicated in sequence. The regeneration process is high in nitric acid recovery rate, almost free of secondary pollution, capable of recycling the heavy metal to the greatest extend and high in market value of the recycled product. And the complete equipment is easy to manufacture, install, maintain and repair, low in energy consumption, and high in economical benefits and environment-friendly benefits.

Description

technical field [0001] The invention relates to the field of nitric acid waste liquid treatment, in particular to a regeneration process and regeneration equipment for the heavy metal-containing nitric acid waste liquid. Background technique [0002] Because nitric acid has no corrosive effect on stainless steel parts, it is widely used in the removal of coatings on workpieces, such as copper coating, nickel coating, zinc coating, etc. The exhausted nitric acid removal solution is very difficult to handle because it contains a large amount of total nitrogen. The treatment of nitric acid waste liquid in the industry is mainly acid-base neutralization, after sedimentation and extraction of heavy metals, and then denitrification treatment, which not only consumes a lot of chemicals, but also consumes a lot of energy, which is easy to cause secondary pollution. Other methods such as oxalic acid replacement and regeneration of nitric acid are simple in process, but have low econ...

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): C02F9/10C01B21/46C02F103/16
Inventor 陈璀董李刚
Owner 昆山市台鑫五金厂
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