BioWin 6.2 includes a new element to model Membrane Aerated Bioreactors. This technology is gaining acceptance worldwide as an effective wastewater treatment approach, particularly for increasing capacity of existing systems and potentially reducing energy consumption.
BioWin 6.2 also contains updates to its Excel reporting templates and functionality, as well as a few minor bug fixes.
Membrane Aerated Bioreactor
A Membrane Aerated Bioreactor (MABR) element has been added to represent this process in BioWin configurations. Physically the MABR element is somewhat analogous to the membrane bioreactor unit. Hollow fiber membrane cassettes are immersed in the mixed liquor of a bioreactor, displacing a certain liquid volume. Gas (typically air) is blown through the inner core of the hollow fibers (the lumen), and oxygen diffuses outwards through the membrane wall. A biofilm develops on the outer surface of the fibers. In most current applications of MABR technology, process air typically is introduced only through the membrane fibers and the bulk liquid is not aerated for process purposes. However, additional aeration can be provided via diffusers on the base of the reactor with oxygen transfer from the bubbles to the bulk liquid in the reactor.
Modeling of these systems is complex. The simple view of an MABR is to think of oxygen permeating outwards from the inner core of the hollow fibers, and entering the biofilm to provide oxygen for nitrification and other biological growth processes. However, CO2 is a product of various biological processes and some CO2 likely will diffuse from the inner biofilm layer back into the lumen, counter-current to the movement of oxygen through the membrane. The mass transfer modeling through the membrane must be applied to all dissolved gases included in the BioWin ASDM (O2, CO2, N2, NH3, N2O, H2, H2S, CH4, and the three industrial components depending on their volatilities) and the direction of movement of individual gas components will depend on the concentration gradient for each component.
BioWin’s one-dimensional dynamic biofilm model is used as the basis to represent the biofilm growing on the outside of the membrane. That is, the biofilm is considered as a number of layers of equal thickness. Mass transfer of soluble components and dissolved gases between layers within the biofilm and from the biofilm outer surface to/from the bulk liquid is handled in the same manner as for other attached growth biofilms. This is also the case for attachment and detachment of solids to/from the outer surface of the biofilm and the movement of solids between layers in the biofilm.
The biofilm model incorporates all of the BioWin ASDM model processes including pH calculations and separate diffusion rates for different state variables. The MABR model has been developed to balance pragmatic design elements with mechanistic modeling rigor, to provide quick solution times, and typical process performance predictions.
When upgrading from BioWin 6.1 to BioWin 6.2 the link above will provide you with a full installation, including the latest device drivers. Please note that this upgrade will not affect older BioWin versions (BioWin 6.1 and earlier) which are separate applications. This means that users can keep their older copies of BioWin.
- BioWin updater will not automatically upgrade BioWin 6.0 to BioWin 6.1. You MUST run the full installation from the link provided. Thereafter the updater will always be checking that your files are up to date.
- The upgrade to 6.2 will not affect older BioWin versions (BioWin 6.0 and earlier) which are separate applications. This means that users can keep their older copies of BioWin
- We are emailing the registered contact for specific BioWin serial number(s). If an organization has multiple copies or users of BioWin, we would be pleased if the registered contact can advise other users of this new version and these upgrade instructions.
Annual license customers can now upgrade to BioWin 6.2; releases and upgrades are included in the annual lease and distributed electronically. Instructions on how to electronically upgrade to BioWin 6.2 can be found here.
Perpetual License customers who purchased after November 1, 2019 will be emailed instructions on how to electronically upgrade to BioWin 6.2 free of charge. If you have not received your upgrade email, please contact us. Customers who purchased BioWin prior to November 1, 2019 may order an upgrade here for US$3,300.
Academic licenses can now be upgraded to BioWin 6.2; releases and upgrades are included in the annually renewed license and distributed electronically. Instructions on how to electronically upgrade to BioWin 6.2 can be found here.
Enjoy your new BioWin 6.2. We look forward to your feedback.