Blowdown Gas Flow Regulation in PSA Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pressure and flow rate fluctuations in the tail gas from adsorption units in PSA processes pose challenges for maintaining steady furnace operations, leading to inefficiencies and the need for larger surge vessels, which are costly.
Innovation Solution
A process that regulates the flow rate of the blowdown gas by sensing pressure and flow rate fluctuations in the tail gas, adjusting the flow rate of the blowdown gas to maintain target limits, thereby reducing the size of the surge vessel required and optimizing PSA unit efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If no flow rate regulation is applied to blowdown gas, then the PSA process operates with simple control, but the tail gas flow rate fluctuates significantly causing furnace operation instability
Solution Approach 1:
The patent implements a feedback control system where a flow sensor monitors the actual flow rate of tail gas and a controller adjusts the blowdown gas flow rate through a control valve to maintain stable tail gas flow. This closed-loop feedback mechanism directly addresses the reliability issue by automatically compensating for flow fluctuations, while the controller and sensor add controlled complexity only where needed for stability.
Solution Approach 2:
The patent introduces a control valve as an intermediary device between the blowdown gas source and the tail gas stream. This intermediary component enables precise regulation of blowdown gas flow rate, acting as a mediator that translates control signals into actual flow adjustments, thereby stabilizing tail gas flow without requiring direct modification of the entire PSA system.
2Reliability
If a large surge vessel is used to dampen tail gas flow fluctuations, then furnace operation stability is maintained, but capital costs increase due to larger equipment requirements
Solution Approach 1:
The feedback control system actively manages tail gas flow fluctuations in real-time, eliminating the need for oversized surge vessels. By continuously monitoring and adjusting blowdown gas flow rate, the system maintains stable tail gas flow with minimal surge capacity, directly reducing the volume and capital cost of surge vessel requirements while preserving furnace operation stability.
Solution Approach 2:
The patent replaces the passive mechanical solution of large surge vessels with an active control system using sensors, controllers, and control valves. This substitution transitions from a bulk mechanical approach (large vessels) to a precise control approach, reducing equipment volume while achieving the same stability outcome through intelligent regulation of blowdown gas flow.
3Volume of stationary object
If the flow rate of blowdown gas is regulated to maintain target tail gas flow, then surge vessel size is reduced, but the complexity of flow sensing and control increases
Solution Approach 1:
The patent employs feedback control where a flow sensor measures actual tail gas flow rate and feeds this information to a controller that adjusts the blowdown gas control valve. This feedback mechanism enables precise surge vessel size reduction through automated flow regulation, with the control complexity concentrated in a dedicated control module rather than distributed throughout the system.
Solution Approach 2:
The control system is designed to be self-regulating, automatically adjusting blowdown gas flow based on real-time tail gas flow measurements without requiring external intervention. The controller and sensor work together in a self-service manner to maintain target flow rates, minimizing the need for additional complex control infrastructure while achieving surge vessel size reduction.
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 the size of the surge vessel needed, improves efficiency, and allows for lower final blowdown pressures and purge pressures, enhancing overall PSA unit performance and reducing capital costs.
Implementation Method 1
a production step (110), which comprises introducing a stream (101) of the feed gas mixture (100) into an adsorption bed undergoing the production step (110) and adsorbing the secondary gas components on the adsorbent in the adsorption bed
Data Source
AI summary
Pressure swing adsorption process for reducing fluctuations in the flow rate of tail gas from the adsorption unit. The flow rate of the stream of blowdown gas is regulated responsive signals from a sensor measuring the pressure and/or flow rate of the tail gas comprising the blowdown gas and purge gas effluent before the tail gas is introduced into a surge vessel.