Fluidized Bed Reactor Exhaust Gas Cleaning via Post-Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for exhaust gas cleaning in fluidized bed reactors require pre-separators to remove large particles, which are energy-intensive, costly, and result in reactors with high structural requirements and limited operational efficiency due to the need for extensive pre-separation of inert solids.
Innovation Solution
A method that allows for the integration of a flow path parallel to the fluidized bed, where pollutants are converted into inert solids, reducing the need for pre-separation and enabling a smaller reactor design by ensuring sufficient residence time for pollutant-sorbent reactions, with a control mechanism to adjust sorbent supply based on unreacted pollutant levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pre-separators are used to remove large particles before the fluidized bed, then the fluidized bed operation is stabilized, but energy consumption increases and device complexity increases
Solution Approach 1:
The patent extracts and removes large particles (>30 μm) from the gas stream using a cyclone separator positioned after the fluidized bed, rather than before. This allows the fluidized bed to operate without pre-separation while still protecting it from excessive particle loading, as the cyclone removes particles that would otherwise accumulate in the fluidized bed.
Solution Approach 2:
Instead of the conventional approach of pre-separating particles before the fluidized bed, the patent inverts the sequence by allowing particles to enter the fluidized bed first and then separating them after. This reversal eliminates the need for energy-intensive pre-separators while achieving the same protective function.
2Reliability
If pre-separators are used to remove large particles before the fluidized bed, then the fluidized bed operation is stabilized, but device complexity and investment costs increase
Solution Approach 1:
The patent extracts and removes large particles (>30 μm) from the gas stream using a cyclone separator positioned after the fluidized bed, rather than before. This allows the fluidized bed to operate without pre-separation while still protecting it from excessive particle loading, as the cyclone removes particles that would otherwise accumulate in the fluidized bed.
Solution Approach 2:
Instead of the conventional approach of pre-separating particles before the fluidized bed, the patent inverts the sequence by allowing particles to enter the fluidized bed first and then separating them after. This reversal eliminates the need for energy-intensive pre-separators while achieving the same protective function.
3Productivity
If the fluidized bed height is increased to ensure sufficient residence time for pollutant-sorbent reactions, then pollutant removal efficiency is improved, but device complexity and space requirements increase
Solution Approach 1:
The patent extends the pollutant removal process continuously from the fluidized bed into a downstream flow path. Pollutants that do not react completely in the fluidized bed continue to react with sorbents along the flow path, ensuring complete removal without requiring excessive fluidized bed height. This continuous action maintains high removal efficiency while reducing structural requirements.
Solution Approach 2:
The patent transitions the reaction process from a vertical dimension (fluidized bed height) to a horizontal dimension (downstream flow path length). This dimensional change allows sufficient reaction time to be achieved through extended horizontal flow rather than increased vertical height, reducing reactor structural requirements.
4Productivity
If the fluidized bed height is increased to ensure sufficient residence time for pollutant-sorbent reactions, then pollutant removal efficiency is improved, but equipment size and investment costs increase
Solution Approach 1:
The patent extends the pollutant removal process continuously from the fluidized bed into a downstream flow path. Pollutants that do not react completely in the fluidized bed continue to react with sorbents along the flow path, ensuring complete removal without requiring excessive fluidized bed height. This continuous action maintains high removal efficiency while reducing structural requirements.
Solution Approach 2:
The patent transitions the reaction process from a vertical dimension (fluidized bed height) to a horizontal dimension (downstream flow path length). This dimensional change allows sufficient reaction time to be achieved through extended horizontal flow rather than increased vertical height, reducing reactor volume.
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 enhances the separation efficiency, reduces sorbent consumption, and maintains a stable fluidized bed operation, achieving lower emissions and improved operational reliability with reduced equipment needs.
Implementation Method 1
a fluidized bed flow reactor (1) with a fluidized bed chamber (2) receiving an expanded fluidized bed
Implementation Method 2
from where the gas flow is extracted upwards in the opposite direction to gravity and the direction of its solid content
Implementation Method 3
a separation chamber through which the gas flows in an antiparallel direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for separating gaseous or particulate materials from a gas flow e.g. an exhaust stream, by means of a fluidized bed flow reactor. A support layer consisting of a large particle fraction is arranged in the fluidised bed. In order to constantly maintain the size, a large particle fraction, which leaves the fluidized bed with the volume flow, is separated from the volume flow by a separator and is fed back into the fluidized bed so that the size of the support layer is maintained. The rate of feedback of the large-particle fraction is lowered in terms of mass as the addition of sorbents to the fluidized bed for reducing the residual pollutant concentration is increased. The separated large particle fraction which is not fed back is removed from the process. Said solution also enables the fluidized bed to be supplied with exhaust gas loaded with solid materials from the large particle fraction without a pre-separator. These pass through the fluidized bed and are only then removed from the process.