FCC Gas Injection Element Ceramic Sleeve Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The maintenance of gas injection systems in Fluid Catalytic Cracking (FCC) units is hindered by erosion caused by catalyst penetration into injection nozzles, leading to frequent replacements and prolonged maintenance times, as existing solutions like ceramic or stellite-coated nozzles are either fragile or require frequent replacement.
Innovation Solution
A gas injection element comprising a ceramic internal element housed within a hollow metal sheath, with complementary internal and external surfaces allowing reversible fixation, enabling easy replacement of the internal element when worn, and a bayonet-style attachment mechanism for simplified installation and removal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ceramic nozzles are used to resist erosion, then erosion resistance is improved, but fragility increases
Solution Approach 1:
The invention uses a composite structure combining ceramic internal element (for erosion resistance) with metal sheath (for mechanical strength and flexibility). This allows the system to benefit from both materials' properties, resolving the contradiction between erosion resistance and fragility.
Solution Approach 2:
The nozzle is divided into separate replaceable components: an internal ceramic element and an external metal sheath. When the ceramic element erodes, only that specific component needs replacement rather than the entire nozzle assembly, addressing both durability and maintenance concerns.
2Reliability
If stellite-coated metal nozzles are used, then erosion resistance is improved, but replacement frequency increases
Solution Approach 1:
The nozzle is segmented into a permanent metal sheath and a replaceable internal ceramic element. The ceramic element can be replaced independently when worn, extending the overall system life without replacing the entire nozzle assembly.
Solution Approach 2:
The internal ceramic element is designed as a consumable component that can be discarded when eroded and replaced. The metal sheath is recovered and retained for continued use, reducing waste and maintenance costs.
3Duration of action of stationary object
If nozzles are made replaceable, then maintenance frequency is reduced, but replacement time increases
Solution Approach 1:
The nozzle is divided into a permanent metal sheath and a replaceable internal ceramic element. This segmentation allows for rapid replacement of only the worn ceramic component without disturbing the sheath or re-soldering operations, significantly reducing maintenance time.
Solution Approach 2:
The internal ceramic element is pre-assembled within the metal sheath during manufacturing with fastening elements already in place. This preliminary assembly allows for quick field replacement by simply detaching the pre-configured ceramic element from the sheath.
4Productivity
If entire distribution system is replaced, then maintenance efficiency is improved, but cost and complexity increase
Solution Approach 1:
The distribution system consists of multiple nozzles, each with replaceable ceramic elements. This segmentation allows selective replacement of individual worn nozzles rather than requiring complete system replacement, reducing both cost and complexity while maintaining efficiency.
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 design reduces maintenance time and frequency by allowing quick and easy replacement of the internal element, minimizing downtime and extending the life of the gas distribution system components.
Implementation Method 1
said internal surfaces of the sheath and external surfaces of the internal element being provided with fastening elements cooperating to reversibly fix the sheath and the internal element
Implementation Method 2
the sheath and the internal element having respectively an internal surface and an external surface of complementary shapes allowing a displacement of the internal element relative to the sheath along a direction parallel to an axis of the passage through
Data Source
Figure 1~3
AI summary
A gas injection element (10) for a system for distributing a gas inside a chamber of a fluid catalytic cracking unit. This injection member comprises a passage (14) extending entirely therethrough, and - an inner ceramic member (20) having an inner surface (22) that entirely delimits the through-passage (14); and - a hollow metal sleeve (30), inside which at least a portion of the inner member (20) is received, the sleeve (30) and the inner member (20) respectively having an inner surface (32) and an outer surface (24) with matching shapes allowing the inner member (20) to move relative to the sleeve (30) in a direction parallel to an axis (X) of the passage (14), the outer (32) and inner surfaces (24) being provided with fastening elements (26, 36) that engage to reversibly fasten the sleeve and the inner member.