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EnviroSim is pleased to announce the addition of one-day specialty courses to its training portfolio.
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WE HAVE MOVED! EnviroSim is pleased to announce its relocation to new offices at McMaster Innovation Park.
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NEW POSITION! EnviroSim is always seeking bright, ambitious, educated people to join our company.
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Sydney, Australia BioWin Training Course, scheduled for October 18 - 20, 2010.
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"The BioWin Advantage" e-tech letter : 1-D Settling Models
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EnviroSim to present at 6th International Conference on Sustainable Water Environment on July 31, 2010 in Newark, Delaware
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Introductory and Advanced BioWin Training Courses scheduled for September 13-17, 2010 at the EnviroSim offices in Hamilton, Ontario.
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EnviroSim to present at AETT Specialty Conference – Recent Advances in the Operation & Control of the Activated Sludge Process, July 15, 2010, Leeds, UK.
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EnviroSim is delighted to announce that its latest version of BioWin is now available with Multi-Language capabilities.
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EnviroSim to present at WEF Specialty Conference – Membrane Applications 2010, June 6 – 9, 2010, Anaheim, CA.
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Dwight Houweling becomes latest EnviroSim team member to achieve the Professional Engineer designation.
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"The BioWin Advantage" e-tech letter : Most Popular Biowin User Questions
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Introductory and Advanced BioWin Training Courses scheduled for April 19 - 23, 2010 at the EnviroSim offices in Hamilton, Ontario.
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BioWin Training for Engineering Applications is scheduled for March 16 – 18 at Tongji University, Shanghai PR China
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EnviroSim is pleased to announce the addition of a new team member, Shelley Potter.
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United Kingdom BioWin Training Course scheduled for January 2010.
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EnviroSim is pleased to announce the opening of our European Business.
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The EnviroSim team wishes to thank everyone who made our presence at WEFTEC 09 truly enjoyable.
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Introductory and Advanced BioWin Training Courses scheduled for November 30 - December 4, 2009 2009 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim is delighted to announce the release of BioWin 3.1, featuring MBR, Microscreen and Cyclone elements as well as a new SBR modeling technique
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EnviroSim is to exhibit at WEFTEC. 09, the 82nd Annual Water Environment Federation Technical Exhibition and Conference, from October 12 to 14, 2009, at McCormick Place, Orlando, FL.
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Melbourne, Australia BioWin Training Course, scheduled for October 26 - 28, 2009.
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EnviroSim is to present at WEFTEC.09, 82nd Annual Water Environment Federation Technical Exhibition and Conference, October 10 to 14, 2009, Orange County Convention Center, Orlando, FL.
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EnviroSim is pleased to announce the addition of a new team member, Leiv Rieger.
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BioWin Seminar and Training scheduled for September 6, 10 & 11, 2009 at the IWA’s Specialized Conference on Nutrient Management in Wastewater Treatment Processes in Krakow, Poland
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EnviroSim to present at IWA Specialized BNR Conference, September 6 - 9, 2009, Krakow, Poland.
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European BioWin User Group Meeting, September 21, 2009, Bordeaux, France.
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EnviroSim to present at 5th IWA Specialised Membrane Technology Conference for Water and Wastewater Treatment, Sep 1 to 3, 2009, Beijing, P.R. China
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EnviroSim contributes to IWA’s Conference on Sustainable Management & Technologies of Sludges, August 8 - 10, 2009, Harbin, PR China.
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EnviroSim launches e-tech letter “The BioWin Advantage”
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Introductory and Advanced BioWin Training Courses scheduled for July 27-31, 2009 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim to present at WEF Specialty Conference - Nutrient Removal 2009, June 28 – July 1 2009, Washington DC.
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EnviroSim contributes to WEF Specialty Conference – Residuals and Biosolids 2009, Sustainable Biosolids Management, May 3 - 6, 2009, Portland, OR.
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EnviroSim contributes to WEAO 2009 Annual Conference –April 5 - 7, 2009, Toronto, ON.
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Introductory and Advanced BioWin Training Courses scheduled for March 30 - April 3, 2009 at the EnviroSim offices in Flamborough, Ontario.
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Australia and New Zealand BioWin User Group Meeting scheduled for December 10, 2008
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Modeling Workshop in China scheduled for November 18-19, 2008
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Australia and New Zealand BioWin Training Course, scheduled for December 3rd - 5th, 2008
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Australia and New Zealand Calibration of Wastewater Plant Simulators Workshop, scheduled for December 8th - 9th, 2008
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Introductory BioWin Training Course scheduled for January 8-9, 2009 in Las Vegas, Nevada.
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EnviroSim is to exhibit at WEFTEC. 08, the 81st Annual Water Environment Federation Technical Exhibition and Conference, from October 18 to 22, 2008, at McCormick Place, Chicago, IL.
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Introductory BioWin Training Course scheduled for November 17-18, 2008 in Montreal, Quebec.
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EnviroSim is to present at WEFTEC.08, 81st Annual Water Environment Federation Technical Exhibition and Conference, October 18 to 22, 2008, McCormick Place, Chicago, IL.
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EnviroSim to present at IWA World Water Congress and Exhibition, Sep 7 to 12, 2008, Vienna, Austria
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EnviroSim is pleased to announce the opening of our Australian office.
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Introductory and Advanced BioWin Training Courses scheduled for August 25-29, 2008 at the EnviroSim offices in Flamborough, Ontario.
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New Authorized Reseller for Algeria, Libya, Mauritania, Morocco and Tunisia
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Introductory BioWin Training Course scheduled for June 30th - July 1st, 2008 at City College of New York, New York, NY
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United Kingdom Calibration of Wastewater Plant Simulators Workshop scheduled for June 11th - 12th, 2008
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New Zealand Training Course scheduled for May 2008.
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Australian Training Course scheduled for May 2008.
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Introductory and Advanced BioWin Training Courses scheduled for May 5-9, 2008 at the EnviroSim offices in Flamborough, Ontario.
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United Kingdom BioWin Training Course scheduled for April & May 2008
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New Authorized Reseller for Iran.
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EnviroSim contributes to WEF Specialty Conference –Residuals and Biosolids 2008, Traditions, Trends and Technologies, March 30 - April 2, 2008, Philadelphia, PA.
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EnviroSim to present at CAWQ Symposium on Water Quality Research, February 11 – 12, 2008, Burlington, Ontario.
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EnviroSim is delighted to announce the release of BW Controller for whole-plant process control simulation.
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Introductory and Advanced BioWin Training Courses scheduled for February 25-29 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim is pleased to announce BioWin 3 enhancements
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WEFTEC 07: A thank you from the EnviroSim Team at WEFTEC.07
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EnviroSim is pleased to announce the return of Dr Chris Bye from sabbatical in Australia.
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United Kingdom BioWin User Group Meeting scheduled for November 22, 2007.
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EnviroSim is to exhibit at WEFTEC.07, 80th Annual Water Environment Federation Technical Exhibition and Conference, October 13 to 17, 2007, San Diego Convention Center, San Diego, CA.
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EnviroSim is to present at WEFTEC.07, 80th Annual Water Environment Federation Technical Exhibition and Conference, October 13 to 17, 2007, San Diego Convention Center, San Diego, CA.
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EnviroSim is pleased to announce the addition of a new team member, Dwight Houweling.
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*UPDATE* BOTH COURSES NOW FULL : Introductory and Advanced BioWin Training Courses scheduled for October 29 - November 2, 2007 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim to present at 2007 Senior Technologic Forum on Water Industry, August 3 - 4, 2007, Beijing, China
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EnviroSim to present at Particle Separation Conference (PS 2007), July 9-12, 2007 in Toulouse, France.
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EnviroSim to present at International Workshop on Monitoring and Sensor for Water Pollution Control, June 13-14, 2007, Tsinghua University, Beijing, China.
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Introductory and Advanced BioWin Training Courses scheduled for July 23-27, 2007 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim to present at WATERMATEX 2007, May 7 – 9, 2007, Washington, DC.
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United Kingdom BioWin Training Course scheduled for June, 2007
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EnviroSim to present at CLONIC PROJECT workshop, April 19 – 20, 2007, Barcelona, Spain.
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EnviroSim to present at WEF / AWWA Specialty Conference – Joint Residuals and Biosolids Management Conference 2007, Biosolids and Residuals: Innovation and Sustainability, April 15 – 18, 2007, Denver, CO.
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EnviroSim to present at WEF / IWA Specialty Conference - Nutrient Removal 2007, The State of the Art, March 4 - 7 2007, Baltimore, Md.
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EnviroSim is delighted to announce the release of BioWin 3 which now includes Biofilm and Sidestream modeling
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Introductory and Advanced BioWin Training Courses scheduled for April 23-27, 2007 at the EnviroSim offices in Flamborough, Ontario.
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EnviroSim is pleased to announce the addition of a new team member, Zhirong Hu
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EnviroSim is pleased to welcome visiting Professor Yves Comeau
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Introductory and Advanced BioWin Training Courses scheduled for January 29 - February 2, 2007 at the EnviroSim offices in Flamborough, Ontario.
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WEFTEC 06: References to BioWin section expanded and a thank you from the EnviroSim Team
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Australian Training Course scheduled for December, 2006
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EnviroSim is to exhibit at WEFTEC.06, 79th Annual Technical Exhibition and Conference, October 21 to 25, 2006, Dallas Convention Center, Dallas, TX.
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New Authorized Reseller for France.
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United Kingdom BioWin Training Course scheduled for September, 2006.
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South Africa BioWin Training Course scheduled for August, 2006.
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EnviroSim to present at IWA Specialized Conference, Biofilm VI, 24 to 27 Sep 2006, Amsterdam, The Netherlands.
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EnviroSim to present at IWA World Water Congress and Exhibition, Workshops & Courses, Sep 7 to 14, 2006, Beijing, PR China.
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New Authorized Reseller for Egypt, Saudi Arabia, United Arab Emirates, Oman, Yemen and Tunisia.
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Australian and New Zealand BioWin Training Courses scheduled for July and November, 2006
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Introductory BioWin Training Course scheduled for July 10th - 11th, 2006 at the EnviroSim offices in Flamborough, Ontario.
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Calibration of Wastewater Plant Simulators Workshop, scheduled for June 19th - 20th, 2006 at the EnviroSim offices in Flamborough, Ontario
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Advanced BioWin Training Course scheduled for April 24th - 25th, 2006 at the EnviroSim offices in Flamborough, Ontario
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Introductory BioWin Training Course scheduled for March 6th - 7th, 2006 at the EnviroSim offices in Flamborough, Ontario
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Correlation for Mass Transfer Coefficient, KLA

Note: An important consideration in the design of diffused air systems is that the overall mass transfer coefficient changes with changing air flow rate; that is, KLa is not "constant". Under dynamic loading conditions, over periods when the oxygen demand is high, and a higher air flow is required, there is a drop-off in transfer efficiency. This is an important factor when determining blower peak air delivery requirements.

Manufacturers generally provide diffuser performance data in the form of a set of curves for a range of diffuser densities showing SOTE/depth (%/m or %/ft) versus air flow rate per diffuser. Typically, for fine bubble systems the curves start in the region of 8%/m (2.5%/ft) for low air flow rates, decrease with increasing air flow, and level off at higher air flows. An example is shown in the diagram below.

Graph

These data reflect the change in the mass transfer coefficient, KLa , with increasing air flow and diffuser density. The data points in the plot below are from aeration tests conducted at two diffuser densities in a 20 foot by 20 foot test tank for diffuser submergences of 9, 14 and 19 feet. [The diffusers used in these tests were 18 inches in diameter, and the numerical values in the plots below should not be seen as typical for other diffuser types]. In the plot the clusters of data points correspond to KLa values for different submergences. Note that the diffuser density, DD%, is defined in terms of the coverage:

Calculation

where AT = Area of aeration tank.

Therefore:

Calculations

where AD = Total area of diffusers in aeration tank.

Graph

Research has shown that the mass transfer coefficient, KLa correlates with the superficial gas velocity – i.e. the air flow rate per unit aerated tank area. In BioWin the KLa value is estimated using a correlation of the form:

Calculations

where C = parameter depending on diffuser density (see below), Y = parameter [Default value in BioWin = 0.82], USG = Superficial gas velocity (m3/m2/day) = QAIR / Area of bioreactor, QAIR = Air flow rate (m3/day).

The parameter C is a function of the diffuser density. In BioWin the C value is determined as follows:

Calculations

where K1 = parameter [Default value in BioWin = 2.5656/day], K2 = parameter [Default value in BioWin = 0.0432].

The diagrams below show how BioWin predicts the relations between (a) KLa and superficial gas velocity, and (b) SOTE (%/m) and air flow per diffuser, for K1 = 1.8 /day and the other parameters presented above.

Graph

Graph

BioWin allows the user to set up plots for bioreactors showing SOTE/depth (%/m or %/ft) versus air flow rate per diffuser [An example system including an SOTE plot can be downloaded from the downloads section on this website]. The chart is shown below. SOTE data are plotted for the diffuser density of the bioreactor in question, and for four other user-selected diffuser densities. The example includes experimental data for a number of diffuser types]. The plot can be compared to manufacturer data, and used as a basis for selecting appropriate parameters (K1 and K2) for a particular diffuser type. Alternatively users can contact EnviroSim to obtain a spreadsheet to assist in parameter selection.

Graph

     

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