Headerless Catalyst Cooler Design for FCC Heat Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing FCC processes face challenges in managing excess heat generated during catalyst regeneration due to heavier hydrocarbon feeds, leading to equipment damage and reduced yields, particularly with internal heat exchangers being difficult to retrofit and service.
Innovation Solution
An external catalyst cooling vessel with a headerless design featuring a central supply tube surrounded by a coaxial heat removal conduit and multiple external heat removal tubes, arranged in a triangular pattern, enhances heat transfer and reduces channeling, allowing for improved catalyst distribution and uniform contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If internal heat exchangers are used for catalyst cooling, then heat transfer efficiency is improved, but device complexity and difficulty of retrofitting and servicing increase
Solution Approach 1:
The heat exchanger is extracted from the internal regenerator structure and placed in an external catalyst cooler vessel. This allows the heat transfer function to be maintained while eliminating the complexity of integrating tubes within the regenerator structure, enabling easier retrofitting and servicing.
Solution Approach 2:
The heat exchanger system is segmented into separate external components: the catalyst cooler vessel, cooling coils, and associated piping are independent modules that can be installed and serviced separately from the regenerator, reducing overall system complexity.
2Area of stationary object
If conventional external heat exchangers with headers are used, then heat transfer area is increased, but device complexity and manufacturing cost increase
Solution Approach 1:
The header and heat removal tubes are merged into an integrated heat removal unit where the tubes are directly connected to the heat removal conduit without separate header components. This maintains the heat transfer area while reducing the number of parts and assembly complexity.
Solution Approach 2:
The heat removal conduit serves multiple functions: it acts as both the coolant distribution manifold and the structural support for the heat removal tubes, eliminating the need for separate header components and reducing device complexity.
3Productivity
If heavier hydrocarbon feeds are used, then productivity is improved, but excess heat generation damages equipment and reduces yields
Solution Approach 1:
The external catalyst cooler vessel acts as an intermediary between the regenerator and the reactor, providing a dedicated heat removal system that controls catalyst temperature before it enters the reactor, preventing excess heat from damaging equipment or reducing yields.
Solution Approach 2:
Catalyst cooling is performed in advance in the external cooler vessel before the catalyst enters the reactor. This preliminary temperature control prevents the catalyst from introducing excess heat into the reaction system, allowing heavier feeds to be processed safely.
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 design achieves a 25-30% reduction in vessel diameter or a 50-100% increase in duty capacity with fewer parts, lower manufacturing costs, and improved thermal control, ensuring uniform heat transfer and reduced shell side bypass.
Implementation Method 1
indirect contact heat exchange is achieved using cooling coils or tubes, through which a cooling fluid is passed
Implementation Method 2
Heat exchangers utilizing cooling coils or tubes running through a fluidized catalyst particle bed
Implementation Method 3
a substantially vertical, cylindrical and close ended heat removal vessel and through the shell side fluid solid particles flow downwardly in the form of dense phase fluidized bed
Implementation Method 4
Heat exchangers utilizing cooling coils or tubes running through a fluidized catalyst particle bed
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
An external catalyst cooler arrangement for an FCC regenerator improves the operation of the catalyst cooler by the use of a heat removal unit design utilizing a central supply tube and central heat removal conduit surrounded by external heat removal tubes connected directly to the central heat removal conduit.