Methane Pyrolysis Reactor with Thermal Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methane pyrolysis techniques face challenges in energy efficiency, catalyst activity degradation, and excessive carbon production, with existing methods requiring separate processes for heating and carbon purification, and struggling to efficiently produce high-purity carbon monoxide.
Innovation Solution
A reactor system that incorporates thermal storage to utilize combustion heat from pure-oxygen combustion of carbon for methane pyrolysis, allowing alternate operation of combustion and pyrolysis in one reactor, and includes a Boudouard reaction to produce high-purity carbon monoxide, with a combination reactor design for efficient carbon utilization and energy management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If methane pyrolysis is carried out at high temperature (900-1200°C) to achieve high conversion rate, then hydrogen production efficiency is improved, but energy consumption increases significantly
Solution Approach 1:
The reactor alternates between exothermic combustion phase and endothermic pyrolysis phase in periodic cycles. During combustion, fuel burns to generate heat and store thermal energy. During pyrolysis, the stored thermal energy is released to drive methane decomposition without external heating, achieving high conversion rates while reducing overall energy consumption.
Solution Approach 2:
The system utilizes phase transitions of thermal energy storage materials (e.g., molten salt changing between solid and liquid phases) to store and release heat. The thermal storage material absorbs heat during combustion phase through phase change and releases it during pyrolysis phase, enabling high-temperature operation without continuous external energy input.
2Quantity of substance
If carbon is produced as a byproduct of methane pyrolysis, then solid carbon material is obtained, but the amount of carbon produced exceeds current market demand when large amounts of methane are reformed
Solution Approach 1:
The excess carbon byproduct, which would normally be waste or require separate purification processes, is converted into a useful fuel source. The carbon is combusted in controlled amounts during the combustion phase to generate thermal energy for the pyrolysis process, transforming a harmful excess into a beneficial energy source and eliminating the need for separate carbon utilization processes.
Solution Approach 2:
The system uses its own byproduct (carbon) to fuel the combustion phase, creating a self-sustaining cycle. The carbon produced during pyrolysis is fed back into the combustion chamber to generate heat, allowing the system to serve itself and eliminate external fuel requirements while balancing carbon production with energy generation.
3Ease of manufacture
If separate processes are used for heating and carbon purification, then process complexity increases, but integration of multiple functions in one reactor increases device complexity
Solution Approach 1:
The reactor combines multiple previously separate functions into a single integrated system: the combustion chamber and pyrolysis reactor are merged into one vessel, thermal energy storage is integrated within the reactor structure, and carbon purification is achieved through the Boudouard reaction occurring in-situ. This eliminates the need for separate heating equipment, carbon separation units, and purification systems.
Solution Approach 2:
The single reactor performs multiple functions simultaneously or sequentially: it serves as both combustion chamber and pyrolysis reactor, the thermal storage material acts as both heat source and heat sink, and the Boudouard reaction zone functions as both reaction chamber and purification unit. This multi-functionality reduces the number of separate equipment pieces while maintaining process efficiency.
4Loss of energy
If pure-oxygen combustion of carbon is used to generate heat for pyrolysis, then energy efficiency is improved, but carbon monoxide production must be controlled
Solution Approach 1:
The carbon monoxide, which would normally be considered a harmful byproduct or pollutant requiring treatment, is converted into a valuable product through the Boudouard reaction. CO2 from the combustion process reacts with additional carbon to produce high-purity carbon monoxide, transforming a potential environmental hazard into a marketable chemical product while maintaining energy efficiency.
Solution Approach 2:
The system controls the oxidation state and chemical composition parameters by utilizing the Boudouard reaction equilibrium. By adjusting temperature, pressure, and reactant ratios, the system optimizes the conversion of CO2 and carbon into CO, changing the chemical parameters to produce desired high-purity carbon monoxide while managing emissions through controlled reaction conditions.
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
Improves energy efficiency, facilitates efficient process operation, and enables convenient production of high-purity carbon monoxide by selectively supplying carbon to carbon dioxide, addressing the limitations of existing methods and achieving sustainable hydrogen and carbon production.
Implementation Method 1
a thermal storage unit that is located within the reaction unit and stores combustion heat generated during the pure-oxygen combustion of the carbon
Implementation Method 2
pure-oxygen combustion of carbon
Implementation Method 3
pyrolysis of methane
Implementation Method 4
the Boudouard reaction for producing high-purity carbon monoxide
Data Source
AI summary
Provided are a reactor for producing hydrogen and carbon through methane pyrolysis by a thermal storage method, and a combination reactor including the same, wherein the reactor includes a reaction unit in which pure-oxygen combustion of carbon and pyrolysis of methane are carried out, a first accommodation unit that supplies oxygen and the carbon to the reaction unit or accommodates carbon and hydrogen obtained by the pyrolysis of the methane, a flame supply unit that generates a flame within the reaction unit, a thermal storage unit that is located within the reaction unit and stores combustion heat generated during the pure-oxygen combustion of the carbon, and a second accommodation unit that accommodates carbon dioxide produced by the pure-oxygen combustion of the carbon or supplies methane to the reaction unit, wherein the pure-oxygen combustion of the carbon and the pyrolysis of the methane are alternately carried out.