Moving Bed Reactor for Sintering Flue Gas Purification
Solution Overview
Problem
Current methods for purifying sintering waste gases from metal production are costly and inefficient due to the need for multiple purification steps and catalyst damage from pollutants like NOx, SOx, and HCl, which require significant equipment and consumable materials.
Innovation Solution
A two-stage counterflow moving bed reactor process using adsorption/absorption agents, where sintering waste gases are purified in a single reactor with ammonium-containing compounds to convert NOx and absorb SOx and HCl, maximizing adsorption capacity and minimizing catalyst damage, and allowing for regeneration and reuse of the adsorption agent.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple purification steps are implemented sequentially, then purification effectiveness is improved, but device complexity and cost increase significantly
Solution Approach 1:
The patent combines multiple purification functions (NOx removal, SOx removal, HCl removal) into a single moving bed reactor by using a dual-layer structure where the lower layer handles acidic gases (SOx, HCl) and the upper layer handles nitrogen oxides (NOx), allowing simultaneous purification of multiple pollutants in one device
Solution Approach 2:
The moving bed reactor is designed as a multi-functional device that can remove different types of pollutants (NOx, SOx, HCl) through different adsorption mechanisms in different layers, making a single device capable of performing multiple purification functions that would traditionally require separate devices
2Reliability
If catalysts are used for NOx removal, then NOx purification is improved, but catalyst damage occurs due to SOx and HCl
Solution Approach 1:
The reactor is divided into two distinct layers: a lower layer for absorbing acidic gases (SOx, HCl) and an upper layer for catalytic NOx removal. This segmentation prevents harmful acidic gases from reaching and damaging the catalyst in the upper layer, while still allowing effective NOx purification
Solution Approach 2:
The lower layer of adsorption material acts as an intermediary barrier that removes SOx and HCl before the gas reaches the upper catalytic layer, protecting the catalyst from harmful substances while allowing the NOx removal function to operate effectively
3Object-affected harmful factors
If preliminary purification stages are added to remove SOx and HCl, then catalyst protection is improved, but equipment cost and process complexity increase
Solution Approach 1:
The protective function against catalyst damage and the NOx removal function are merged into a single integrated moving bed reactor with dual layers, eliminating the need for separate preliminary purification equipment and reducing overall process complexity
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 method simplifies the purification process, achieves up to 100% utilization of adsorption capacity, reduces catalyst damage, and lowers costs by using a single reactor stage with efficient NOx and SOx removal, avoiding the need for additional preliminary purification stages and consumable materials.
Implementation Method 1
adsorbs at least the main quantity of SOx and perhaps of others of the pollutants from the sintering waste gas in the pore system of the adsorption and/or absorption agent
Implementation Method 2
absorb SOx and HCl
Implementation Method 3
be intimately mixed subsequently for the conversion of the NOx, for example, into N2 and water vapor, with an ammonium-containing compounds
Implementation Method 4
adsorbs at least the main quantity of NOx components from the sintering waste gas and/or their reaction products, on the surface of the adsorption and/or absorption agent
Data Source
AI summary
A method for purifying waste gases of an at least partially burnt solid fuel to reduce pollutants such as SOx and/or HCl and NOx. The waste gas flows into a moving bed reactor from below through a lower and upper layer of an adsorption and/or absorption agent already polluted with NOx, SOx and/or HCl. SOx and/or HCl components are adsorbed from the waste gas into the NOx loaded adsorption and/or absorption agent. Thereafter, the waste gas is mixed with an ammonium-containing compound and flows through an upper horizontal gas inflow and bulk material removal tray of the moving bed reactor into the upper layer of the adsorption and/or absorption agent already polluted with NOx and small quantities of SOx and/or HCl. During the throughflow of the upper layer, NOx components are adsorbed from the waste gas onto the adsorption/absorption agent.