Movable Support Bed for Biological Methanation Reactor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Biological methanation reactors face inefficiencies due to poor access of reagents (dihydrogen and carbon dioxide) to methanogenic microorganisms, leading to stoichiometry imbalances and excess reagents in the gas product, which complicates the production of synthetic methane suitable for injection into natural gas networks.
Innovation Solution
A reactor design featuring a movable support material with a high surface-to-volume ratio for microorganism colonization, combined with recirculated water and heat management systems, enhances reagent access and concentration, optimizing the methanation reaction while minimizing reactor volume and residual reagents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a stirred reactor is used to disperse gases in fine bubbles, then reagent access to microorganisms is improved, but the system requires wall penetration for the agitator which compromises airtightness and safety
Solution Approach 1:
The patent replaces the mechanical agitator system with a gas circulation system that uses a pump and sparger to dissolve and redistribute gases. This substitution eliminates the need for wall penetrations while maintaining effective gas-liquid contact through controlled dissolution and re-sparging, thus preserving airtightness and safety without sacrificing reaction efficiency.
2Duration of action of moving object
If a bacterial bed reactor is used with counter-current circulation, then contact time between reactants and microorganisms is increased, but gas flow is hindered by bacterial growth leading to preferential flow paths and lower production rates
Solution Approach 1:
The patent applies preliminary action by dissolving gases in water before introducing them to the microbial bed. The gases are pre-dissolved in a separate circulation loop, then reintroduced through a sparger at the bottom of the reactor. This preliminary dissolution prevents gas channeling and ensures uniform distribution throughout the bed, maintaining both adequate contact time and high production rates.
Solution Approach 2:
The patent uses water as an intermediary medium to transfer gases to the microbial bed. Instead of introducing gases directly into the bed where they would create preferential flow paths, the gases are first dissolved in water in a circulation system, then the saturated water serves as a carrier to deliver gases uniformly throughout the bed, eliminating channeling while maintaining contact time.
3Ease of operation
If free culture of microorganisms is used in a stirred reactor, then microorganisms are well dispersed, but they are very diluted in the medium which does not promote contact between microorganisms and reagents
Solution Approach 1:
The patent uses water as an intermediary to enhance microorganism-reagent contact. The system circulates water through the microbial bed, allowing dissolved gases to be delivered uniformly throughout the medium. This water circulation intermediary ensures that even though microorganisms are dispersed in free culture, they remain in constant contact with reagent-laden water, maintaining both dispersion and 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 design increases reaction capacity per unit volume, reduces reagent residuals, and improves the stoichiometry of the methanation reaction, resulting in a more efficient and compact biological methanation process.
Implementation Method 1
In biological methanation, the reaction takes place in the liquid phase thanks to methanogenic microorganisms from the Archaea domain, for example.
Implementation Method 2
a support material for forming a bed of methanogenic flora, having a density lower than the density of water, mobile in translation along the longitudinal axis of the enclosure
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The reactor (100) for the biological methanation of dihydrogen or a dihydrogen-rich gas and carbon dioxide or a carbon dioxide-rich gas, comprises: - an enclosure (105) having a longitudinal end (106) referred to as "low" and an opposite longitudinal end (107) referred to as "high", said enclosure comprising, near the low end: - a primary inlet (110, 405) for water, - an inlet (115, 405) for dihydrogen or dihydrogen-rich gas and - an inlet (120, 405) for carbon dioxide or carbon dioxide-rich gas and close to the high end: - an outlet (125) for synthetic methane or synthetic methane-rich gas and - a primary outlet (130) for water, - a support material (135) for forming a methanogenic flora bed, having a density less than the density of water, movable in translation along the longitudinal axis (101) of the enclosure, configured to receive a methanogenic flora and - between the support material, on the one hand, and the outlet for methane and the outlet for water, on the other hand, a surface (140) for retaining the perforated support material forming a stop for the longitudinal movement of the support material at the position of said surface.