Modular Agitation Inserts for Uniform Cracking Coil Heat Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thermal cracking processes face challenges in achieving homogeneous temperature distribution and efficient heat transfer in hydrocarbon streams due to laminar flow profiles and coke deposition, requiring expensive recoiling of coils.
Innovation Solution
A modular agitation means comprising a tubular component with inserts that create different pressure environments to manipulate the flow profile and molecular distribution, using helical protrusions to achieve a homogeneous temperature profile and efficient heat transfer without recoiling existing coils.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a laminar flow profile is established in the hydrocarbon stream due to cylindrical coil geometry, then the flow is stable and predictable, but the temperature distribution becomes non-uniform with higher velocities in the center and lowest velocity at the edges, making it difficult to achieve full cracking and avoid coking
Solution Approach 1:
The flow cross-section is segmented into multiple zones with different flow characteristics by introducing inserts that create localized turbulence. This segmentation allows different regions of the flow to be optimized independently, ensuring uniform temperature distribution while maintaining overall flow stability.
Solution Approach 2:
The flow regime is transitioned from laminar to turbulent by introducing dynamic elements (inserts with protrusions) that disrupt the smooth flow. This dynamic change ensures better mixing and more uniform temperature distribution across the flow cross-section, preventing both overheating and insufficient cracking.
2Productivity
If high temperatures are used to increase cracking efficiency and yields, then the cracking reaction is enhanced, but coke deposition increases on the inside of the coils due to severe dehydrogenation
Solution Approach 1:
Turbulence is introduced to dynamically mix the hydrocarbon stream, ensuring uniform temperature distribution throughout the flow cross-section. This prevents localized overheating and severe dehydrogenation that lead to coke deposition, while maintaining high cracking efficiency through optimized heat transfer.
Solution Approach 2:
The flow regime parameter is changed from laminar to turbulent, which fundamentally alters the heat and mass transfer characteristics. This parameter change ensures that high temperatures can be maintained for efficient cracking without the harmful side effect of excessive coke deposition.
3Power
If the flow velocity is increased to improve heat transfer efficiency, then the heat transfer rate increases, but the residence time in the coil decreases, making it more difficult to achieve full cracking
Solution Approach 1:
Turbulence is introduced to enhance heat transfer efficiency at high flow velocities. The turbulent flow pattern ensures that even though the residence time is reduced, the heat transfer rate increases sufficiently to maintain effective cracking reactions.
Solution Approach 2:
The flow regime is changed from laminar to turbulent, which fundamentally improves the heat transfer coefficient. This allows the system to operate at higher flow velocities with shorter residence times while maintaining adequate heat transfer for complete cracking.
4Power
If existing coils are recoiled to improve heat transfer efficiency, then the heat transfer rate increases, but the process is expensive and results in furnace downtime
Solution Approach 1:
The coil structure is segmented by introducing inserts within the existing tubes, allowing heat transfer improvement without replacing the entire coil. This segmentation approach avoids the need for expensive recoiling and minimizes furnace downtime.
Solution Approach 2:
The inserts are installed during routine maintenance or before the cracking season begins, preparing the system in advance. This preliminary action avoids the need for expensive and time-consuming coil recoiling operations.
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 provides a homogeneous temperature distribution and reduced coke formation, extending coil lifetime and reducing energy consumption by maintaining efficient heat transfer and minimizing pressure loss.
Implementation Method 1
the at least one insert is configured to agitate said gaseous stream of hydrocarbon material flowing along said flow passage by creating different pressure environments in the tubular component
Implementation Method 2
The insert is configured to agitate a gaseous stream of hydrocarbon material flowing along said flow passage by creating different pressure environments in the tubular component
Implementation Method 3
Thermal cracking process are used to breakdown complex organic molecules into smaller, more useful alkanes and alkenes which form the basis for the production of polymers
Implementation Method 4
The energy required to crack the carbon-carbon bonds is usually supplied by indirect heating of the hydrocarbon stream
Data Source
Figure 1A~2B
Figure 3A~3E
AI summary
The present disclosure refers to a modular agitation means for agitating a gaseous stream of hydrocarbons, in particular in cracking processes, the agitation means comprising a tubular component and at least one insert. The present disclosure further refers to an insert for cracking coils and tubes, respectively, and processes carried out therein.