Flexible Pneumatic Tube for Dense Catalyst Loading in Bayonet Tubes

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for loading catalysts into bayonet tubes in steam reforming reactors are inefficient, particularly due to the need for dense and homogeneous distribution, and cannot adapt to variations in tube dimensions, leading to issues like overheating, unbalanced flow, and particle breakage.

Innovation Solution

A pneumatic device using a flexible removable tube with lateral orifices to control gas flow and particle fall, combined with a conveyor belt system, ensures dense and uniform loading while adapting to varying tube dimensions, slowing particle fall to prevent breakage and maintaining a fixed bed state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a pneumatic loading system is used to fill bayonet tubes with catalyst, then loading speed increases, but particle breakage occurs due to high gas flow velocities

Engineering Contradiction:
Improveloading speedVSAvoidparticle breakage
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The gas flow is divided into two independent circuits: a primary circuit through the internal tube and a secondary circuit through the annular space via the flexible tube. This segmentation allows each circuit to be optimized independently - the primary circuit provides high velocity for rapid loading while the secondary circuit provides gentle counter-current flow that prevents particle breakage by reducing turbulence and eddy currents.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system changes the physical parameters of gas flow by introducing a counter-current flow in the annular space that opposes the downward particle motion. This counter-current creates a more uniform velocity distribution and reduces the harmful effects of high-velocity direct downward flow, thereby preventing particle breakage while maintaining high loading productivity.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If high gas flow rate is used to increase loading density, then loading efficiency improves, but homogeneous distribution of catalyst deteriorates

Engineering Contradiction:
Improveloading densityVSAvoidhomogeneous distribution
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The gas flow system is segmented into two circuits that work together: the primary circuit through the internal tube provides the main driving force for rapid particle transport, while the secondary circuit through the flexible tube in the annular space provides a counter-current that distributes particles more uniformly. This segmentation enables both high loading density and homogeneous distribution simultaneously.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The flexible tube acting as an intermediary element in the annular space mediates between the high-velocity primary flow and the particle bed. It introduces a counter-current that acts as a buffer, slowing down particles gradually and ensuring homogeneous distribution while maintaining the overall high loading rate enabled by the primary circuit.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If fixed loading tubes are used in bayonet tubes, then structural stability is maintained, but adaptability to varying tube dimensions is lost

Engineering Contradiction:
Improvestructural stabilityVSAvoidadaptability to tube dimensions
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The loading tube is made flexible rather than rigid, allowing it to adapt to variations in bayonet tube dimensions while maintaining structural integrity. The flexible tube can be inserted and withdrawn easily, and its flexibility allows it to conform to slight dimensional variations in different tubes while still providing effective gas flow for catalyst loading.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The loading system transitions from a static fixed tube to a dynamic flexible tube that can be inserted, positioned, and removed as needed. This dynamic approach allows the system to adapt to varying tube dimensions and facilitates easy maintenance and replacement, while the tube maintains sufficient structural stability to withstand the gas flows required for effective catalyst loading.

Inventive Principle:
Principle #15Dynamics

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 solution achieves efficient, dense, and homogeneous catalyst loading with low breakage rates and consistent pressure distribution across all tubes, meeting industrial-scale requirements and adapting to changing tube dimensions.

Implementation Method 1

a pneumatic device using a flexible removable tube with lateral orifices to control gas flow and particle fall... slowing particle fall to prevent breakage

Methodology Applied
Scientific EffectGas flow drag: Drag

Implementation Method 2

a pneumatic device using a flexible removable tube with lateral orifices to control gas flow and particle fall... maintaining a fixed bed state

Methodology Applied
Scientific EffectFluidization: Fluidisation

Data Source

PatentEP2908934B1Method using a pneumatic system for dense catalyst loading in bayonet tubes for a steam reforming reactor-exchanger, comprising a removable gas supply tube
Publication Date: 2017.08.30 IFP ENERGIES NOUVELLES
  • EP2908934B1 patent drawingFigure 1
  • EP2908934B1 patent drawingFigure 2

AI summary

The invention relates to a device and method for densely and homogeneously loading catalyst into the annular space of bayonet tubes, used in a steam reforming reactor, said device being of the pneumatic type and using a removable gas supply tube.