Catalytic NOx SOx Oxidation with Atmospheric Oxygen
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for removing nitrogen oxides (NOx) and sulphur oxides (SOx) from flue gases are expensive and inefficient, particularly due to the low solubility of nitric oxide in water and the use of costly and corrosive oxidants like hydrogen peroxide and ozone, which require complex and costly systems for oxidation.
Innovation Solution
A method utilizing atmospheric oxygen as the oxidation reagent, combined with a catalytic oxidation process and wet-scrubbing using an adsorption and oxidation reactor with a catalyst, such as cobalt chloride supported on silica gel, to oxidize NOx and SOx, followed by ammonia treatment to produce ammonium nitrate and ammonium sulphate fertilizers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If hydrogen peroxide or ozone is used as oxidant for NOx oxidation, then oxidation efficiency is improved, but system complexity and operational costs increase
Solution Approach 1:
The patent replaces expensive oxidants (hydrogen peroxide, ozone) with atmospheric oxygen, which is abundant and free. The catalyst is used continuously without replacement, effectively making the system use cheap, readily available materials instead of expensive consumables.
Solution Approach 2:
The catalyst acts as an intermediary that enables the oxidation reaction between NOx and atmospheric oxygen without being consumed. This mediator allows the use of simple atmospheric oxygen instead of complex oxidant systems, reducing both cost and system complexity while maintaining oxidation efficiency.
2Productivity
If hydrogen peroxide or ozone is used as oxidant, then NOx oxidation is effective, but maintenance costs and safety risks increase
Solution Approach 1:
Atmospheric oxygen replaces expensive and hazardous oxidants, eliminating safety risks associated with handling and storing hydrogen peroxide and ozone. The system uses abundant, non-hazardous air as the oxidation source.
Solution Approach 2:
The catalyst serves as a safe intermediary that facilitates the oxidation reaction using benign atmospheric oxygen, avoiding the need for harmful oxidants while achieving the same NOx removal efficiency.
3Reliability
If separate treatment processes are used for NOx and SOx, then each pollutant can be treated effectively, but overall system complexity and cost increase
Solution Approach 1:
The patent combines NOx and SOx treatment into a single catalytic oxidation process using atmospheric oxygen. Both pollutants are oxidized simultaneously in one reactor, eliminating the need for separate treatment systems and reducing overall complexity while maintaining effective removal of both pollutants.
Solution Approach 2:
The catalyst system performs multiple functions: it oxidizes both NOx and SOx using atmospheric oxygen, and the oxidized products are then absorbed in the wet scrubbing system. This multi-functional approach replaces multiple specialized treatment systems with a single integrated process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces operational and maintenance costs, provides a safer environment, and effectively removes NOx and SOx in a single-step process, producing valuable fertilizers while avoiding the need for expensive oxidants and complex systems.
Implementation Method 1
catalytic oxidation of nitrogen oxides (NOx) and sulphur oxides (SOx) by atmospheric oxygen
Implementation Method 2
oxidation of nitrogen to its higher valence states yields NOx soluble in water
Implementation Method 3
a gas absorber becomes effective... absorption of NOx gases
Implementation Method 4
contacting the oxidised NOx and SOx dissolved in a liquid phase of said adsorbing dispersion, with ammonia to produce ammonium nitrate and ammonium sulphate fertilisers
Data Source
AI summary
A NOx and SOx oxidation with atmospheric oxygen to remove NOx and SOx from flue gases. The combined system for catalytic oxidation and wet-scrubbing of NOx and SOx from a flue gas and manufacturing fertilizers includes: an air separation unit for separating atmospheric oxygen from air and producing an air stream enriched with atmospheric oxygen, an adsorption and oxidation reactor containing an oxidation catalyst and carrying out the catalytic oxidation of NOx and SOx by said oxygen to yield nitric and sulphuric acids, a separator and reactor control unit for separation of products and liquids and controlling the reaction; and a vessel containing ammonia streaming said ammonia into the reactor or into the control unit to react with the nitric and sulphuric acids and to yield the fertilizers.