CO2 Absorption Tower Demister Flow Control Under Low Gas Throughput
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Solution Overview
Problem
The flow rate of exhaust gas supplied to a demister in a CO2 recovery device decreases due to changes in the exhaust gas supply conditions, leading to a decrease in flow velocity and deterioration of mist removal performance.
Innovation Solution
A CO2 recovery device with a flow velocity regulating section that includes a blower to increase the flow velocity of exhaust gas, and a differential pressure acquisition unit to control the flow rate through a demister, maintaining a constant flow velocity by adjusting the supply of exhaust gas using additional supply lines and flow rate regulating valves.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the flow rate of exhaust gas supplied to the demister decreases, then the demister operates under lower flow conditions, but the flow velocity of exhaust gas through the demister decreases leading to deterioration of mist removal performance
Solution Approach 1:
A flow velocity regulating section is introduced as an intermediary device between the exhaust gas supply and the demister. This section includes a differential pressure acquisition unit that measures the pressure difference across the demister and a flow velocity increasing unit (blower) that actively regulates the flow velocity. When the measured differential pressure indicates low flow velocity, the blower increases the flow velocity to maintain mist removal performance, thus resolving the contradiction between reduced flow rate and maintained flow velocity.
2Productivity
If the flow rate of exhaust gas decreases due to changes in supply source conditions, then less gas is processed, but the mist removal performance deteriorates due to reduced flow velocity through the demister
Solution Approach 1:
The flow velocity regulating section implements a feedback control mechanism where the differential pressure acquisition unit continuously monitors the pressure difference across the demister, which correlates with flow velocity. Based on this feedback, the flow velocity increasing unit (blower) automatically adjusts the exhaust gas flow velocity to maintain it within a predetermined range. This ensures reliable mist removal performance regardless of variations in exhaust gas flow rate from the supply source.
3Speed
If additional components are added to regulate flow velocity, then flow velocity can be maintained, but device complexity increases
Solution Approach 1:
The flow velocity regulating section is designed with multi-functionality to minimize overall device complexity. The differential pressure acquisition unit not only measures pressure for flow velocity control but also provides information about system operating conditions. The flow velocity increasing unit (blower) serves both to maintain flow velocity through the demister and to ensure adequate gas circulation throughout the system. This multi-functional design reduces the need for separate dedicated components for each function.
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
The device maintains a constant flow velocity of exhaust gas through the demister, ensuring effective mist removal even when the exhaust gas flow rate decreases, and recirculates exhaust gas to prevent oxidative deterioration of absorption liquid and reduce the need for additional heating.
Implementation Method 1
a cooling tower into which an exhaust gas containing carbon dioxide is introduced to cool the exhaust gas
Implementation Method 2
an absorption tower into which the exhaust gas cooled in the cooling tower is introduced and which brings the exhaust gas into contact with an absorption liquid to remove the carbon dioxide from the exhaust gas
Implementation Method 3
a demister that is disposed inside the absorption tower body and is configured to remove mist contained in the exhaust gas as the exhaust gas flows therethrough
Data Source
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AI summary
A CO2 recovery device includes: a cooling tower into which an exhaust gas containing carbon dioxide is introduced to cool the exhaust gas; and an absorption tower into which the exhaust gas cooled in the cooling tower is introduced and which brings the exhaust gas into contact with an absorption liquid to remove the carbon dioxide from the exhaust gas, in which the absorption tower has an absorption tower body through which the exhaust gas is flowable and which has a tubular shape, and a demister that is disposed inside the absorption tower body and is configured to remove mist contained in the exhaust gas as the exhaust gas flows therethrough, and the CO2 recovery device further comprises a flow velocity regulating section that regulates the flow velocity of the exhaust gas flowing through the demister to be within a predetermined range.