Pyrolytic Reactor Annular Nozzle Shockwave Mixing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional pyrolytic reactors face challenges in achieving high conversion and selectivity for desired products like acetylene due to non-uniform mixing of feedstock and carrier streams, leading to undesirable reactions and reduced efficiency.
Innovation Solution
A pyrolytic reactor design that injects feedstock using multiple annularly arranged nozzles, creating a shockwave in the reaction zone to mix the carrier gas stream and feedstock simultaneously, eliminating the need for a separate mixing zone and optimizing conditions for high temperature and rapid quenching to favor acetylene formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single row of uniform injectors is used to inject feedstock, then the device complexity is reduced, but the mixing uniformity of feedstock and carrier stream deteriorates
Solution Approach 1:
The single row of uniform injectors is segmented into multiple rows with different configurations. The patent employs a first row of injectors positioned at a first location and a second row of injectors positioned at a second location, allowing each row to contribute differently to the mixing process and achieve more uniform distribution without excessive complexity
Solution Approach 2:
Different regions of the reactor receive different injector configurations tailored to local mixing needs. The first row of injectors is positioned to address mixing requirements at the first location, while the second row addresses requirements at the second location, creating locally optimized mixing throughout the reactor volume
2Stability of the object's composition
If a mixing zone is added to ensure full mixing of carrier stream and feedstock, then the mixing uniformity improves, but the residence time increases leading to undesirable reactions
Solution Approach 1:
Mixing is performed preliminarily through the multi-row injector configuration before the feedstock enters the reaction zone. The injectors are designed to create thorough mixing in the injection zones themselves, so that when material enters the reaction zone, it is already well-mixed and ready for immediate reaction, eliminating the need for a separate mixing zone
Solution Approach 2:
The mixing function is extracted from a separate mixing zone and integrated directly into the injection system. By incorporating mixing capabilities into the injector rows positioned at different locations, the patent eliminates the need for a dedicated mixing zone that would otherwise increase residence time
3Productivity
If high temperature combustion is used to generate carrier stream, then the pyrolysis reaction efficiency improves, but the formation of unwanted byproducts increases
Solution Approach 1:
The patent carefully controls temperature parameters throughout different zones. High temperature combustion is used to generate the carrier stream for efficiency, but the multi-row injector system enables rapid cooling and temperature stabilization in subsequent zones, preventing excessive temperatures that would promote unwanted byproduct formation while maintaining reaction 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 approach enhances conversion and selectivity for acetylene by ensuring uniform mixing and controlled residence times, preventing decomposition and forming higher hydrocarbons, thereby increasing the yield of acetylene and reducing the formation of less valuable products.
Implementation Method 1
The carrier gas stream is transitioned from supersonic speed to subsonic speed to create a shockwave in a reaction zone
Implementation Method 2
combusting the fuel and the oxidizer in a combustion zone to create a carrier gas stream
Implementation Method 3
exposing the feedstock to high temperature combustion gases causing the feedstock to pyrolyze into the desired unsaturated product
Data Source
AI summary
Methods and apparatus to produce alkynes are described. The method includes combusting fuel and an oxidizer in a combustion zone to create a carrier gas stream, which is accelerated to supersonic speed in an expansion zone. A feedstock material is injected into a feedstock injection zone using two or more pluralities of injection nozzles. The injection nozzles are arranged annularly. The carrier gas stream is transitioned from supersonic speed to subsonic speed to create a shockwave in a reaction zone. The reaction zone is directly connected to the feedstock injection zone, and the shockwave is created adjacent to the feedstock injection zone. The carrier gas stream and the feedstock material are simultaneously mixed and reacted.