A method for absorbing and separating ammonia from ammonia-containing waste gas

A waste gas and ammonia gas technology, applied in separation methods, preparation/separation of ammonia, separation of dispersed particles, etc., can solve the problems of low added value of ammonium salt products, high energy consumption in the water regeneration process, and large consumption of separation materials, etc., to achieve Strong ammonia molecular affinity and selective recognition ability, low saturated vapor pressure, efficient removal and recovery effects

Active Publication Date: 2019-04-23
ZHEJIANG UNIV
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The technology of water absorption method is mature, but there are disadvantages such as strong solvent volatility, high energy consumption in the water regeneration process, large waste water discharge, and low ammonia recovery rate.
Using aqueous solution of inorganic acid or organic acid as absorbent can improve ammonia recovery rate, but there are problems such as difficult desorption, strong solvent volatility, strong corrosion, and low added value of ammonium salt products.
Other common methods include low-temperature recovery, membrane separation, adsorption, etc., which have disadvantages such as low ammonia recovery rate, many steps, and large consumption of separation materials.

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

Embodiment 1

[0037]The absorbent is a hybrid deep eutectic solvent mixed with hydroquinone / choline chloride / ethylene glycol (molar ratio 3:1:3). Synthetic ammonia tail gas composition (volume percentage): hydrogen 51.8%, nitrogen 19.3%, ammonia 6.5%, argon 3.6%, methane 18.8%. The tail gas of synthetic ammonia enters from the bottom of the absorption tower at 3.8MPa, and the absorbent is added to the top of the absorption tower, and the absorbent is in countercurrent contact with the tail gas of synthetic ammonia for absorption at 30°C to ensure that most of the ammonia is absorbed, and the bottom of the tower is enriched. Ammonia absorption liquid, insoluble nitrogen, hydrogen, methane and other residual tail gases are obtained at the top of the tower.

[0038] The absorption liquid at the bottom of the tower enters the desorption tower, adopts the method of temperature rise and desorption, the desorption temperature is controlled at 70°C, the pressure is 0.3MPa, ammonia gas is obtained f...

Embodiment 2

[0040] The absorbent is a hybrid deep eutectic solvent mixed with resorcinol / choline chloride / glycerol (molar ratio 3:1:5). Synthetic ammonia tail gas composition: hydrogen 59.5%, nitrogen 22.3%, ammonia 5.3%, argon 3.8%, methane 9.1%. As in Example 1, countercurrent contact and absorption with the absorbent at 20°C and 4.0 MPa, desorb ammonia gas from the absorbing liquid at 65°C and 0.2 MPa, and the absorbent at the bottom of the tower is recovered and recycled. The recovery rate of ammonia can reach 99.1%.

Embodiment 3

[0042] The absorbent is a hybrid deep eutectic solvent mixed with phloroglucinol / tetrabutylammonium chloride / 1,2-propanediol (molar ratio 2:1:4). Composition of synthetic ammonia tail gas: hydrogen 56.1%, nitrogen 20.5%, ammonia 3.9%, argon 4.7%, methane 14.8%. As in Example 1, countercurrent contact and absorption with the absorbent at 20°C and 3.5MPa, the absorption liquid is heated and decompressed at 65°C and 0.08MPa to desorb ammonia gas, and the absorbent is recovered and recycled at the bottom of the tower. The recovery rate of ammonia can reach 99.5%.

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 absorbing and separating ammonia gas from ammonia-containing exhaust gas. The method comprises the following steps: adopting a hybrid eutectic solvent as an absorbent, the solvent contacting with ammonia-containing exhaust gas to obtain an ammonia-absorbing liquid, and then conducting the desorption of the ammonia-absorbing liquid to obtain ammonia gas. The hybrid eutectic solvent consists of three components, weak acid compounds, salt compounds and additives. The invention adopts the method of absorption and desorption by using the hybrid eutectic solvent as the absorbent to recover and separate ammonia gas. The absorbent has high ammonia solubility and separation selectivity, and can achieve the efficient separation and recovery of ammonia gas.

Description

technical field [0001] The invention relates to the field of separation, recovery and purification of ammonia-containing waste gas, in particular to a method for absorbing and separating ammonia from ammonia-containing waste gas by using a hybrid deep eutectic solvent. Background technique [0002] A large amount of ammonia-containing waste gas is produced in chemical processes such as synthetic ammonia production, liquid ammonia storage, and ammonia refrigeration. If it is discharged directly, it will not only pollute the atmosphere and endanger human health, but also cause a huge waste of resources. Therefore, it is of great practical significance to separate and recover ammonia from ammonia-containing waste gas such as synthetic ammonia tail gas. [0003] Solvent absorption is a common method for separating ammonia from ammonia-containing waste gas, and the absorbent used is mainly water or an aqueous acid solution. The technology of water absorption method is mature, bu...

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 Patents(China)
IPC IPC(8): B01D53/14C01C1/12
CPCB01D53/1418B01D53/1493B01D2252/50B01D2257/406C01C1/12
Inventor 杨启炜李煜惠邢华斌任其龙苏宝根张治国鲍宗必
Owner ZHEJIANG UNIV
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