Recycle Pyrolysis Oil Cracking with Propylene Fractionator Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Recycling waste materials is economically challenging due to the need for expensive processing and physical sorting, and large-scale production facilities struggle to efficiently process diverse waste materials while maintaining or enhancing ethylene or propylene production.
Innovation Solution
A process involving the cracking of a cracker feedstock comprising recycle content pyrolysis oil composition (r-pyoil) and non-recycle content propane in a cracker furnace, followed by separation in a propylene fractionator to enrich propylene and deplete propane, utilizing reflux streams and pressure differentials to optimize separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If waste materials are processed through expensive physical sorting to achieve pure compositions, then the purity of waste streams is improved, but the processing cost increases significantly
Solution Approach 1:
The patent extracts and processes different hydrocarbon components (ethylene, propylene, butadiene) simultaneously from mixed waste pyrolysis oil in a single cracker furnace operation, eliminating the need for separate sorting processes for each component while maintaining high purity recovery through targeted fractionation
Solution Approach 2:
The cracker furnace and downstream separation train are designed to handle multiple waste feedstock types and produce multiple valuable olefin products in one integrated process, making the system universally applicable to diverse waste streams without requiring separate processing lines for each waste type
2Adaptability or versatility
If large-scale production facilities process diverse waste materials, then the versatility of recycling is improved, but the efficiency of maintaining or enhancing ethylene or propylene production decreases
Solution Approach 1:
The patent adjusts cracker operating parameters (temperature, residence time, steam-to-carbon ratio) and fractionation conditions (reflux ratios, column temperatures, pressure differentials) to optimize the simultaneous production of ethylene and propylene from variable waste feedstocks, maintaining high productivity despite feedstock diversity
Solution Approach 2:
The process incorporates analysis of effluent composition to adjust fractionation operations, using real-time or near-real-time feedback on olefin distribution to optimize separation efficiency and product yields from diverse waste feedstocks
3Manufacturing precision
If the propylene fractionator processes recycle content propylene composition, then the concentration of propylene in the overhead stream is improved, but the mass flow rate of propane in the overhead stream increases
Solution Approach 1:
The fractionation process is divided into multiple stages with intermediate side draws and reflux streams, allowing progressive separation of propylene from propane and other components, achieving high propylene concentration while managing propane carryover through staged removal
Solution Approach 2:
A reflux stream is introduced as an intermediary between the column feed and overhead product, allowing selective removal of lighter components and adjustment of the overhead composition to achieve desired propylene concentration while controlling propane content through the mediating reflux action
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
Enhances the production of ethylene and propylene, improves the efficiency of propylene fractionation, and reduces processing costs by incorporating recycle content compositions, thereby optimizing the separation of olefin-containing streams.
Implementation Method 1
cracking a cracker feedstock comprising a recycle content pyrolysis oil composition (r-pyoil) and a stream comprising non-recycle content propane in a cracker furnace to provide an olefin-containing effluent
Implementation Method 2
separating the column feed stream in the propylene fractionator into an overhead enriched in propylene and a bottoms stream depleted in propylene
Data Source
AI summary
Processes and systems for making recycle content hydrocarbons, including olefins, from recycled waste material. Recycle waste material may be pyrolyzed to form recycle content pyrolysis oil composition (r-pyoil), at least a portion of which may then be cracked to form a recycle content olefin composition (r-olefin). The r-olefin may then be further separated into product streams in a separation zone downstream of the cracker furnace. The presence of recycle content hydrocarbons may facilitate more efficient operation of one or more distillation columns in the separation zone, including the propylene fractionator.