Methanation Reactor Liquid Water Injection Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methanation reactors face challenges in efficiently cooling the reaction, leading to high manufacturing costs, non-optimized space utilization, and premature catalyst deactivation due to coke and carbonyl formation, with existing systems failing to effectively manage heat exchange and catalyst toxicity.
Innovation Solution
A methanation reactor design that introduces water in the liquid phase into the fluidized bed, where it vaporizes and participates in the reaction, reducing coke and carbonyl formation, and utilizes a water recycling system to optimize temperature control and heat exchange, allowing for efficient production of methane and thermal energy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If throughwall cooled reactors with reactor walls cooled by cooling fluid are used, then heat exchange is achieved, but the surface areas required for heat exchange are large and reactor manufacturing costs are high
Solution Approach 1:
The patent uses a fluidized bed of catalytic particles that creates a porous, highly surface-area structure. This fluidized bed acts as an extended heat exchange surface throughout the reactor volume, eliminating the need for large external heat exchange surfaces while maintaining efficient heat removal through the natural circulation of particles and cooling gas.
Solution Approach 2:
The invention transitions from two-dimensional heat exchange through reactor walls to three-dimensional heat exchange distributed throughout the entire reactor volume. The fluidized bed particles provide heat exchange surfaces in all spatial dimensions, dramatically increasing the effective heat transfer area without increasing reactor external dimensions.
2Loss of energy
If thermal oil is circulated through heat exchangers in fluidized bed systems, then heat transfer coefficients are high, but the use of thermal oils is limited to reaction temperatures of around 380°C to 400°C
Solution Approach 1:
The patent changes the physical state parameter of the cooling medium from liquid thermal oil to gaseous cooling fluid. This parameter change enables operation across a much wider temperature range, as gases can withstand higher temperatures without degradation, while still maintaining effective heat transfer through the fluidized bed's enhanced convection and large surface area.
3Temperature
If water is injected above the catalytic bed to cool the reaction, then cooling is achieved, but coke and carbonyl formation is not limited
Solution Approach 1:
The patent introduces water at the bottom of the reactor before the gas phase reactants enter the catalytic bed. This preliminary action ensures that water is already present in vapor form and distributed throughout the bed, creating a protective atmosphere that prevents coke and carbonyl formation on the catalyst surfaces before harmful reactions can occur.
Solution Approach 2:
Water vapor acts as an intermediary substance that mediates between the cooling function and the catalyst protection function. By introducing water at the bottom, it serves dual purposes: cooling the reaction through evaporation and preventing harmful side reactions by maintaining a water-rich environment around the catalyst particles.
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 design reduces reactor size, minimizes carbonyl formation, and enhances catalyst longevity by vaporizing water within the reactor, optimizing temperature control and heat exchange, resulting in improved yield and reduced manufacturing costs while ensuring efficient cooling and thermal energy co-generation.
Implementation Method 1
the injected water is vaporized upon contact with the hot bed
Implementation Method 2
the injected water is vaporized upon contact with the hot bed
Implementation Method 3
A fluidized catalyst bed helps to homogenize the temperature of the reactive zone
Implementation Method 4
Methanation is an industrial process of catalytic conversion of hydrogen and carbon monoxide or carbon dioxide into methane
Implementation Method 5
a means (125) for condensing water vapor present downstream of the methane and water outlet
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a methanation reactor (10) for reacting dihydrogen with at least one carbon-based compound and producing methane, comprising: a hollow body (105) designed to receive a fluidised bed of catalytic particles (106) and comprising an inlet (110) for each carbon-based compound and for dihydrogen and an outlet (115) for methane and water. The reactor is characterised in that it also comprises an inlet (120) for the injection of liquid-phase cooling water into the fluidised bed. In certain embodiments, each carbon-based compound is a gas, the reactor comprising at least one water-injection nozzle and at least one injection nozzle for a gas comprising the carbon-based gas and dihydrogen, at least one water-injection nozzle being positioned below at least one gas-injection nozzle. In certain embodiments, the flow rate of water introduced into the hollow body depends on the temperature measured in the reactor.