U-Loop Fermenter Pressure Zoning for Gas Mass Transfer

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Solution Overview

Problem

Conventional fermentation processes face inefficiencies in mass transfer of gaseous substrates into the liquid phase, leading to reduced productivity and high energy consumption, particularly in processes involving methanotrophic bacteria, due to poor gas utilization and separation in traditional fermenters.

Innovation Solution

The U-shape and/or nozzle U-loop fermenter design with pressure controlling devices in different zones allows for optimized gas transfer by increasing pressure in specific zones to enhance solubility and mass transfer, while reducing pressure elsewhere to facilitate gas release, along with gas flushing mechanisms to improve waste gas removal and prevent explosive mixtures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional stirring tanks with compressed air injection are used, then gas mixing is achieved, but energy consumption is excessive and mass transfer efficiency is insufficient

Engineering Contradiction:
Improvemass transfer efficiencyVSAvoidenergy consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The fermenter is divided into multiple vertical zones (aeration zone, separation zone, downward flow zone) with distinct functions. Gas injection occurs at specific locations rather than throughout the entire tank, segmenting the mass transfer process to improve efficiency while reducing overall energy requirements.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different zones within the fermenter have different pressure conditions optimized for their specific functions. The aeration zone operates under higher pressure to enhance gas solubility and mass transfer, while other zones operate at lower pressures, creating local quality variations that improve overall process efficiency and reduce energy consumption.

Inventive Principle:
Principle #3Local quality

2Productivity

If high pressure is applied throughout the fermenter to improve gas solubility, then mass transfer improves, but waste gas removal becomes difficult and energy consumption increases

Engineering Contradiction:
Improvegas solubility and mass transferVSAvoidwaste gas accumulation
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The fermenter is divided into multiple vertical zones (aeration zone, separation zone, downward flow zone) with distinct functions. Gas injection occurs at specific locations rather than throughout the entire tank, segmenting the mass transfer process to improve efficiency while reducing overall energy requirements.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different zones within the fermenter have different pressure conditions optimized for their specific functions. The aeration zone operates under higher pressure to enhance gas solubility and mass transfer, while other zones operate at lower pressures, creating local quality variations that improve overall process efficiency and reduce energy consumption.

Inventive Principle:
Principle #3Local quality

3Productivity

If high pressure is used to improve mass transfer, then gas dissolution improves, but the risk of explosive gas mixtures in the headspace increases

Engineering Contradiction:
Improvemass transfer rateVSAvoidexplosive gas mixture risk
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

Different zones within the fermenter have different pressure conditions optimized for their specific functions. The aeration zone operates under higher pressure to enhance gas solubility and mass transfer, while other zones operate at lower pressures, creating local quality variations that improve overall process efficiency and reduce energy consumption.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system converts the potential harm of high pressure (explosive risk) into a benefit by spatially separating high-pressure and low-pressure zones. The high-pressure zone enhances mass transfer while the low-pressure zone safely manages gas removal, transforming the hazard into a controlled process feature.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 significantly improves the mass transfer and utilization of gaseous substrates, reduces energy consumption, and enhances the productivity of fermentation processes by optimizing gas solubility and separation, making it suitable for continuous operation and cost-effective production of single cell protein.

Implementation Method 1

controlling the pressure differently in the circulating fermentation liquid in at least two different zones in the fermenter by increasing the pressure in at least a first zone of the U-part in the fermenter in relation to the pressure in another zone

Methodology Applied
Scientific EffectPressure increase: Pressure Increase

Implementation Method 2

thereby increasing the mass transfer of the at least one added gaseous substrate component from the gas phase into the liquid phase in that zone

Methodology Applied
Scientific EffectMass transfer: Diffusion

Implementation Method 3

followed by reducing the pressure in relation to the pressure in the first zone of the U-part, in the circulating fermentation liquid before it enters another zone

Methodology Applied
Scientific EffectPressure reduction: Depressurisation

Implementation Method 4

whereby the circulating fermentation liquid is circulated in the fermenter by the liquid circulation means

Methodology Applied
Scientific EffectCirculation: Convection

Data Source

PatentEP2376616B1U-shape and/or nozzle u-loop fermenter and method of fermentation
Publication Date: 2020.01.08 UNIBIO AS
  • EP2376616B1 patent drawingFigure 1
  • EP2376616B1 patent drawingFigure 2~3
  • EP2376616B1 patent drawingFigure 4

AI summary

A fermenter and a method of fermentation in a U-shape and/or nozzle U-loop fermenter (100) comprising a U-part having an essentially vertical down-flow part (101), an essentially vertical up-flow part (102) and a substantially horizontal connecting part (103), which connects the lower ends of the down-flow part (101) and the up-flow part (102), a top part (104) which is provided above the U-part and has a diameter which is substantially larger than the diameter of U-part, means for creating liquid circulation in U-part of the fermenter, and one or more gas injection points (110) for the introduction and dispersion of the gas(ses) into the fermentation liquid. The pressure may be controlled differently in certain zones of the fermenter by pressure controlling devices (105,106,108) e.g. by increasing the pressure in certain zones of the fermenter in relation to the pressure in other zones of the fermenter, or decreasing the pressure in a zone of the fermenter in relation to the pressure in another zone of the fermenter.