Argon condensation system and method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing method of using once-through heat exchangers to condense argon-rich vapor in air separation units faces challenges with dry out and flammability hazards due to high boiling temperature hydrocarbons freezing and concentrating, leading to control issues with crude liquid oxygen flow rates.
Innovation Solution
Implementing a system with multiple once-through heat exchangers connected to an argon column, where crude liquid oxygen flow transducers and controllers ensure proportional flow rates based on vaporization surface areas, and temperature sensors adjust flow to prevent dry out and maintain equal temperatures, thereby controlling the reflux and product flow rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If once-through heat exchangers are used to condense argon-rich vapor, then device complexity is reduced, but dry out occurs and flammability hazards arise due to hydrocarbon concentration
Solution Approach 1:
The patent implements flow transducers to measure crude liquid oxygen flow rates and controllers to adjust flow distribution to multiple heat exchangers. This feedback control system prevents dry out conditions by ensuring adequate liquid flow to each heat exchanger, thereby eliminating the flammability hazard while maintaining the simple once-through heat exchanger structure.
Solution Approach 2:
The patent introduces flow transducers and controllers as intermediary devices between the crude liquid oxygen source and the heat exchangers. These intermediaries measure and regulate the liquid oxygen flow, preventing hydrocarbon concentration and dry out conditions that would otherwise create flammability hazards in the simplified once-through heat exchanger system.
2Reliability
If crude liquid oxygen flow rate is increased to prevent dry out, then safety is improved, but control precision deteriorates due to flow distribution issues
Solution Approach 1:
The patent divides the crude liquid oxygen flow into multiple separate streams, each directed to individual heat exchangers through separate control valves and flow transducers. This segmentation allows precise control of flow rates to each heat exchanger independently, maintaining both safety by preventing dry out and control precision through individualized flow management.
Solution Approach 2:
The patent applies different flow rates to different heat exchangers based on their specific requirements, vaporization surface areas, and operating conditions. Each heat exchanger receives customized liquid oxygen flow control through local sensors and actuators, achieving both safety and precision by tailoring the flow quality to each specific location's needs.
3Reliability
If multiple heat exchangers are used with flow control, then dry out is prevented, but device complexity increases
Solution Approach 1:
The patent enables each heat exchanger to self-regulate its liquid oxygen flow through locally installed flow transducers and control valves. This self-service capability allows the system to automatically maintain adequate flow rates to prevent dry out without requiring complex centralized control, thereby achieving reliability while limiting the increase in device 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 system effectively condenses argon-rich vapor, preventing dry out and flammability hazards while maintaining consistent flow rates and product quality, enhancing the efficiency and safety of the argon reflux condensation process.
Implementation Method 1
the argon-rich vapor column overhead is condensed in a plurality of once-through heat exchangers through indirect heat exchange with a crude liquid oxygen column bottoms
Implementation Method 2
argon-rich vapor streams are condensed within condensation passages of the once-through heat exchangers to produce an argon-rich liquid product stream
Implementation Method 3
a plurality of crude liquid oxygen streams composed of a crude liquid oxygen column bottoms of the higher pressure column are partially vaporized in the vaporization passages of the once-through heat exchangers through indirect heat exchange
Data Source
Figure N/A
AI summary
An argon reflux condensation system and method in which a plurality of once-through heat exchangers are connected to an argon column of an air separation plant to condense argon-rich vapor streams for production of reflux to the argon column. Condensation of the argon-rich vapor streams is brought about through indirect heat exchange with crude liquid oxygen streams that partially vaporize and are introduced into a lower pressure column of the plant for further refinement. The flow rate of the crude liquid oxygen streams are sensed and controlled at locations in the plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Feed stream flow rate to the argon column is controlled in response to air flow rate to the plant and product flow rate is controlled in response to the feed stream flow rate to the argon column.