Method for recycling ammine in ammonium paratungstate production

A technology for the recovery of ammonium paratungstate and ammonia, applied in the field of ammonia recovery, can solve the problems of increasing ammonia wastewater treatment links, low concentration of ammonia water, environmental pollution, etc., and achieve the effects of reducing production costs, preventing air pollution, and reducing corrosion

Inactive Publication Date: 2009-05-27
JIANGXI RARE EARTH & RARE METALS TUNGSTEN GRP
View PDF0 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

During the crystallization process of ammonium paratungstate production, most of the free ammonia in the crystallization process solution is converted into ammonia gas and chemical changes occur in the process to release ammonia gas. If the volatilized ammonia is not recycled, not only

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 recycling ammine in ammonium paratungstate production

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0013] The present invention will be described in detail below in conjunction with the drawings, principles of the present invention and process steps.

[0014] During the evaporative crystallization process of ammonium paratungstate, the free ammonia in the crystallization pot solution and the ammonia and water vapor released during the crystallization process volatilize in gaseous form. The reaction equation is as follows:

[0015] h 2 O(lq)=H 2 O(g)

[0016] NH 3 h 2 O(lq)=NH 3 (g)+H 2 O(lq)

[0017] 12(NH 4 ) 2 WO 4 (lq)=5(NH 4 ) 2 O12WO 3 (s)+NH 3 (g)+H 2 O(lq)

[0018] The inventive method comprises the following steps:

[0019] Start the fan 16 to make the pipeline connected to the upper end of the closed crystallization pot body generate negative pressure for vacuum collection, so that the vacuum degree in the closed crystallization pot body is controlled at 10.0 to 14.0kPa, and the evaporated water and ammonia mixed gas 10 is sucked into the pipeline,...

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 provides a method for recycling ammonia during the production of ammonium paratungstate. During the evaporation and crystallization of a solution for producing the ammonium paratungstate, free ammonia in the solution and ammonia released by the crystallization process can be volatilized in a gas state. Firstly, a closed vessel is used to collect gaseous ammonia; secondly, the ammonia is reclaimed through the mode of condensation and separation; and finally the reclaimed ammonia can be returned to the main production process and be used for preparing a strippant. The method reduces the consumption of liquid ammonia during the production of the ammonium paratungstate, thereby greatly reducing the production cost and having an ammonia reclamation rate of above 90 percent. Simultaneously, the method prevents the air pollution caused by a large amount of evaporated and overflowed ammonia gas; and the atmospheric emission reaches national standards. Therefore, the method reduces the corrosion of workshop equipment and realizes the reclamation of the ammonia, thereby not only realizing considerable economic benefits, but also realizing certain social and environmental benefits.

Description

technical field [0001] The invention relates to a method for recycling ammonia, in particular to a method for recycling ammonia in the process of producing ammonium paratungstate. Background technique [0002] Ammonia is very soluble in water with a solubility of 1:700. During the crystallization process of ammonium paratungstate production, most of the free ammonia in the crystallization process solution is converted into ammonia gas and chemical changes occur in the process to release ammonia gas. If the volatilized ammonia is not recycled, not only a lot of ammonia is wasted, but also Will pollute the environment. Although there is a method of reducing the pollution of gaseous ammonia through simple spraying and recovery, the concentration of the absorbed ammonia water is low, and the process of ammonia wastewater treatment is increased. Therefore, it is necessary to fully recover and comprehensively utilize ammonia to meet the requirements of energy saving, emission re...

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): C01C1/12
Inventor 姚丽华邹庆敏李文凯李锦华王光明
Owner JIANGXI RARE EARTH & RARE METALS TUNGSTEN GRP
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