Immobilising Microalgae and Cyanobacteria as Biocomposites: New Opportunities to Intensify Algae Biotechnology and Bioprocessing

There is a groundswell of interest in applying phototrophic microorganisms, specifically microalgae and cyanobacteria, for biotechnology and ecosystem service applications. However, there are inherent challenges associated with conventional routes to their deployment (using ponds, raceways and photobioreactors) which are synonymous with suspension cultivation techniques. Cultivation as biofilms partly ameliorates these issues; however, based on the principles of process intensification, by taking a step beyond biofilms and exploiting nature inspired artificial cell immobilisation, new opportunities become available, particularly for applications requiring extensive deployment periods (e.g., carbon capture and wastewater bioremediation). We explore the rationale for, and approaches to immobilised cultivation, in particular the application of latex-based polymer immobilisation as living biocomposites. We discuss how biocomposites can be optimised at the design stage based on mass transfer limitations. Finally, we predict that biocomposites will have a defining role in realising the deployment of metabolically engineered organisms for real world applications that may tip the balance of risk towards their environmental deployment.

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Experimental study of CO2 solubility in high concentration MEA solution for intensified solvent-based carbon capture

MATEC Web of Conferences ◽

10.1051/matecconf/201927201004 ◽

2019 ◽

Vol 272 ◽

pp. 01004 ◽

Cited By ~ 1

Author(s):

Eni Oko ◽

Toluleke E. Akinola ◽

Chin-Hung Cheng ◽

Meihong Wang ◽

Jian Chen ◽

...

Keyword(s):

Carbon Capture ◽

Process Intensification ◽

Solubility Data ◽

High Concentration ◽

Co2 Solubility ◽

Capture Process ◽

Process Economics ◽

Extended Uniquac ◽

Electrolyte Nrtl ◽

Capture Techniques

The solvent-based carbon capture process is the most matured and economical route for decarbonizing the power sector. In this process, aqueous monoethanolamine (MEA) is commonly used as the solvent for CO2 scrubbing from power plant and industrial flue gases. Generally, aqueous MEA with 30 wt% (or less) concentration is considered the benchmark solvent. The CO2 solubility data in aqueous MEA solution, used for modelling of the vapour-liquid equilibria (VLE) of CO2 in MEA solutions, are widely published for 30 wt% (or less) concentration. Aqueous MEA with higher concentrations (from 40 to 100 wt%) is considered in solvent-based carbon capture designs with techniques involving process intensification (PI). PI techniques could improve the process economics and operability of solvent-based carbon capture. Developing PI for application in capture process requires CO2 solubility data for concentrated MEA solutions. These data are however limited in literature. The modelling of the vapour-liquid equilibria (VLE) of CO2 in MEA solutions for PI-based solvent capture techniques involving stronger MEA solution of about 80 wt% concentration requires solubility data at the concentration. In this study, the data for 80 wt% MEA is presented for 40,60, 100 and 120oC. The experimental technique and analytical procedure in this study were validated by comparing the measurements for 30 wt% MEA with data from the literature. The data from this study can be fitted to VLE models such as electrolyte NRTL, extended UNIQUAC etc. which is an important component of solvent-based capture model using MEA as the solvent. More accurate VLE models will improve the prediction accuracy of capture level, rich loading etc. using PI-based solvent-based capture model.

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Hierarchical calibration and validation for modeling bench-scale solvent-based carbon capture. Part 1: Non-reactive physical mass transfer across the wetted wall column

Greenhouse Gases Science and Technology ◽

10.1002/ghg.1682 ◽

2017 ◽

Vol 7 (4) ◽

pp. 706-720 ◽

Cited By ~ 4

Author(s):

Chao Wang ◽

Zhijie Xu ◽

Canhai Lai ◽

Greg Whyatt ◽

Peter Marcy ◽

...

Keyword(s):

Mass Transfer ◽

Carbon Capture ◽

Calibration And Validation ◽

Bench Scale ◽

Physical Mass ◽

Wetted Wall Column

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Electric Field Control of the Polluting Emissions from a Propane Flame

Global NEST Journal ◽

10.30955/gnj.000191 ◽

2013 ◽

Vol 3 (2) ◽

pp. 95-108

Keyword(s):

Mass Transfer ◽

Electric Field ◽

Heat Mass Transfer ◽

Carbon Capture ◽

Flame Temperature ◽

Fuel Combustion ◽

Electric Field Effect ◽

Electric Field Effects ◽

Field Effects ◽

Polluting Emissions

The present study is performed with the aim to reduce the levels of polluting emissions from fuel combustion that produce acid rains and the greenhouse effect (NOx, CO2). The electric field effects on the processes of heat/mass transfer and propane combustion are studied in order to perform electric control of the levels of polluting emissions from the flame. The results of experimental studies show the direct influence of the electric field's enhanced mass transfer on local variations of the flame composition and fuel combustion. The related variations of the flame temperature, processes of soot formation, carbon capture and deposition along the flame channel flow are studied by varying the field strength and the equivalence ratio of the propane-air mixture. The results show that the electric field effect on soot for- mation, carbon capture and sequestration, for fuel-rich flame flow, can be used to reduce the levels of CO2 emissions from the flame. In addition, the field-enhanced heat/ mass transfer to the channel walls, for fuel-lean conditions, can be used to control the fuel combustion, flame temperature and temperature- sensitive levels of NOx emissions. The most pronounced electric field effects on fuel combustion and composition of the products are observed in the limit of the weak fields (U<1,2 kV, E<105 V m-1).

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Effect of Different Configurations on Bubble Cutting and Process Intensification in a Micro-Structured Jet Bubble Column Using Digital Image Analysis

Processes ◽

10.3390/pr9122220 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2220

Author(s):

Guanghui Chen ◽

Zhongcheng Zhang ◽

Fei Gao ◽

Jianlong Li ◽

Jipeng Dong

Keyword(s):

Mass Transfer ◽

Image Analysis ◽

Flow Field ◽

Digital Image ◽

Bubble Size ◽

Digital Image Analysis ◽

Liquid Velocity ◽

Bubble Column ◽

Process Intensification ◽

Interfacial Area

An experimental study was conducted in this work to investigate the effect of different configurations on bubble cutting and process intensification in a micro-structured jet bubble column (MSJBC). Hydrodynamic parameters, including bubble size, flow field, liquid velocity, gas holdup as well as the interfacial area, were compared and researched for a MSJBC with and without mesh. The bubble dynamics and cutting images were recorded by a non-invasive optical measurement. An advanced particle image velocimetry technique (digital image analysis) was used to investigate the influence of different configurations on the surrounding flow field and liquid velocity. When there was a single mesh and two stages of mesh compared with no mesh, the experimental results showed that the bubble size decreased by 22.7% and 29.7%, the gas holdup increased by 5.7% and 9.7%, and the interfacial area increased by more than 34.8% and 43.5%, respectively. Significant changes in the flow field distribution caused by the intrusive effect of the mesh were observed, resulting in separate liquid circulation patterns near the wire mesh, which could alleviate the liquid back-mixing. The mass transfer experiment results on the chemical absorption of CO2 into NaOH enhanced by a mass transfer process show that the reaction time to equilibrium is greatly reduced in the presence of the mesh in the column.

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Mass transfer in falling film microreactors: measurement techniques and effect of operational parameters

Reviews in Chemical Engineering ◽

10.1515/revce-2018-0065 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

Ali Alhafiz Mohammed ◽

David Lokhat

Keyword(s):

Mass Transfer ◽

Measurement Techniques ◽

Process Intensification ◽

Liquid Films ◽

Falling Film ◽

Operational Parameters ◽

Transfer Enhancement ◽

Mass Transfer Enhancement ◽

The Relationship ◽

Common Target

Abstract Falling film microreactors have contributed to the pursuit of process intensification strategies and have, over the years, been recognized for their potential in performing demanding reactions. In the last few decades, modifications in the measurement techniques and operational parameters of these microstructured devices have been the focus of many research studies with a common target on process improvement. In this work, we present a review dedicated to falling film microreactors, focusing on the recent advances in their design and operation, with particular emphasis on mass transfer enhancement. Analysis of the recent techniques for the measurement of mass transfer as well as the operational parameters used and their effect on the target objective, particularly in the liquid phase (being the limiting phase reactant), are included in the review. The relationship between the hydrodynamics of falling thin liquid films and the microreactor design, the discrepancies between measured and model results, the major challenges, and the future outlook for these promising microreactors are also presented.

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Pulsed Multiphase Flows—Numerical Investigation of Particle Dynamics in Pulsating Gas–Solid Flows at Elevated Temperatures

Processes ◽

10.3390/pr8070815 ◽

2020 ◽

Vol 8 (7) ◽

pp. 815

Author(s):

Arne Teiwes ◽

Maksym Dosta ◽

Michael Jacob ◽

Stefan Heinrich

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Multiphase Flows ◽

Gas Flow ◽

Elevated Temperatures ◽

Process Intensification ◽

Particle Dynamics ◽

Transport Processes ◽

Pulse Combustion ◽

New Processing

Although the benefits of pulsating multiphase flows and the concomitant opportunity to intensify heat and mass transfer processes for, e.g., drying, extraction or chemical reactions have been known for some time, the industrial implementation is still limited. This is particularly due to the lack of understanding of basic influencing factors, such as amplitude and frequency of the pulsating flow and the resulting particle dynamics. The pulsation generates oscillation of velocity, pressure, and temperature, intensifying the heat and mass transfer by a factor of up to five compared to stationary gas flow. With the goal of process intensification and targeted control of sub-processes or even the development of completely new processing routes for the formation, drying or conversion of particulate solids in pulsating gas flows as utilized in, e.g., pulse combustion drying or pulse combustion spray pyrolysis, the basic understanding of occurring transport processes is becoming more and more important. In the presented study, the influence of gas-flow conditions and particle properties on particle dynamics as well as particle residence time and the resulting heat and mass transfer in pulsating gas–solid flows are investigated.

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