Method and system for removing nitrite from slurry through simultaneous desulfurization and denitrification based on calcium-based quaternary ammonium salt catalyst

A quaternary ammonium salt, desulfurization and denitrification technology, applied in the direction of chemical instruments and methods, separation methods, dispersed particle separation, etc., can solve secondary pollution, unsuitable for nitrite, difficult to remove nitrite, etc. To achieve the effect of recycling

Inactive Publication Date: 2019-01-11
HUANENG POWER INT INC +1
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Among them, the ion exchange method is widely used in the advanced treatment of nitrite, but because nitrite is very stable and has high solubility in the slurry, and there are other anions (sulfate, nitrate and carbonate, etc.) in the slurry and quaternary ammonium salt catalysts, it is difficult to adsorb and remove nitrite, so this method is not suitable for the combined removal of calcium-based + quaternary ammonium salt catalysts to remove nitrite in the absorption slurry
However, other methods are likely to cause secondary pollution, re-release the absorbed NOx into the atmosphere, and the reaction temperature is relatively high, which affects the economics of the method.

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 and system for removing nitrite from slurry through simultaneous desulfurization and denitrification based on calcium-based quaternary ammonium salt catalyst

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0047] In the sulfamic acid liquid mixing tank, a sulfamic acid solution with a concentration of 0.5% is first prepared, and the amount of the prepared sulfamic acid solution is adjusted according to the actual amount of the extracted slurry, and then transported to the reaction kettle. The filtrate in the filtrate buffer tank is injected into the reaction kettle through the solution pump, and the addition time is controlled at 30 minutes. When the slurry was added, the pH value during the reaction was detected by the pH meter installed on the reaction kettle, and it was observed that the pH value was stable in the range of 1.3 to 1.5, and the reaction temperature was detected to be 20°C. The exhaust gas above the reactor is drawn into the Rosemount flue gas analyzer, and the total amount of NOx released during the entire reaction process is continuously monitored to be below 8ppm. The liquid in the reaction kettle was sampled, and the nitrite in it was detected by naphthalene...

Embodiment 2

[0049] In the sulfamic acid liquid preparation tank, a sulfamic acid solution with a concentration of 1.5% is first prepared, and the amount of the prepared sulfamic acid solution is adjusted according to the actual amount of the extracted slurry, and then transported to the reaction kettle. The slurry in the filtrate buffer tank is injected into the reaction kettle through the solution pump, and the addition time is controlled at 90 minutes. When the slurry was added, the pH value during the reaction was detected by the pH meter installed on the reaction kettle, and it was observed that the pH value was stable in the range of 1.3 to 1.5, and the reaction temperature was detected to be 20°C. The exhaust gas above the reactor is drawn into the Rosemount flue gas analyzer, and the total amount of NOx released during the entire reaction process is continuously monitored to be below 15ppm. The liquid in the reaction kettle was sampled, and the nitrite in it was detected by naphtha...

Embodiment 3

[0051] In the sulfamic acid liquid preparation tank, a sulfamic acid solution with a concentration of 1.0% is first prepared, and the amount of the prepared sulfamic acid solution is adjusted according to the actual amount of the extracted slurry, and then transported to the reaction kettle. The slurry in the filtrate buffer tank is injected into the reaction kettle through the solution pump, and the addition time is controlled at 60 minutes. When the slurry was added, the pH value during the reaction was detected by the pH meter installed on the reaction kettle, and it was observed that the pH value was stable in the range of 1.3 to 1.5, and the reaction temperature was detected to be 20°C. The exhaust gas above the reactor is drawn into the Rosemount flue gas analyzer, and the total amount of NOx released during the entire reaction process is continuously monitored to be below 13ppm. The liquid in the reaction kettle was sampled, and the nitrite in it was detected by naphtha...

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 and system for removing nitrite from slurry through simultaneous desulfurization and denitrification based on a calcium-based quaternary ammonium salt catalyst. The method comprises: A, removing solid precipitates in absorption slurry containing nitrite, limestone and a calcium-based quaternary ammonium salt catalyst to obtain a filtrate, B, preparing a sulfamic acid solution through sulfamic acid as a reducing agent, C, injecting the filtrate into the sulfamic acid solution and carrying out an azo-reaction process so that nitrite ions are reduced into nitrogengas through sulfamic acid, and D, carrying out an azo-reaction process after injection of the filtrate so that nitrite is removed. The method and system realize fast and full treatment on the nitritemixed slurry. The method and system can effectively remove the nitrite in the calcium-based quaternary ammonium salt catalyst absorbing slurry, do not cause secondary pollution and catalyst consumption during the treatment process, realize the recycling of the absorption slurry, reduce the NO2 in the flue gas into N2 and discharge the N2 into air.

Description

technical field [0001] The invention belongs to the technical field of air pollutant control, and relates to the field of advanced treatment and reuse of wet desulfurization and denitrification slurry, in particular to a method and system for removing nitrite from slurry with simultaneous desulfurization and denitrification by a calcium-based-quaternary ammonium salt catalyst. Background technique [0002] my country is the world's largest coal producer and consumer. Coal combustion produces a large amount of pollutants such as sulfur dioxide, nitrogen oxides, soot, and organic volatiles, causing serious air pollution, which not only damages people's physical and mental health, but also affects the sustainable development of the economy and society. Coal-fired flue gas purification has become the focus of research in the field of atmospheric governance in recent years. Existing flue gas purification technologies include limestone-gypsum desulfurization, SCR denitrification,...

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): B01D53/86B01D53/60B01D53/78
CPCB01D53/78B01D53/8637
Inventor 郭中旭赵婷雯姚明宇程广文杨成龙蔡铭李阳
Owner HUANENG POWER INT INC
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