The Effect of Bio-Domes and Bio-Shells on Algae

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1 The Effect of Bio-Domes and Bio-Shells on Algae Introduction In most wastewater lagoons, because of the long retention times, and relative quiescent nature of the water body, it is very common for these systems to experience significant algae blooms during the summer months that can cause permit violations, as well as contribute to eutrophication in the lagoon s receiving water body. This problem only becomes worse in southern / warmer climates. In 2002 Dr. Kraig Johnson began the research that would ultimately lead to the invention of the device now known as a Bio-Dome. While the original intent of his research was to create a product capable of providing year round nitrification in a wastewater lagoon, WCS soon started to see additional and unexpected benefits to TSS levels in all our installations and pilot studies. From the time of WCS s first installation in 2008 we have monitored the TSS levels of all our projects and have a growing body of evidence that proves that both the Bio- Domes and Bio-Shells show a remarkable impact in reducing the concentrations of single cellular algae in wastewater lagoons.

2 Both the Bio-Domes and the Bio-Shells are submerged, aerated, fixed film, bio-reactor technologies that rely on high surface area to volume media to propagate the growth of bacteria inside each unit for the purposes of providing accelerated treatment within a wastewater lagoon environment. Below is a cross section diagram of the WCS Bio-Domes Air In Water Surface Dome Shells Water Movement Concrete Base Bottom of Lagoon Bubble Distribution Tubes The bio-reactors sit on the bottom of a lagoon, elevated on a concrete base. In order to circulate the wastewater through the media, the bio-reactors rely on the principles of air-lift to pull water in from the bottom of the lagoon and then carry it to the surface of the lagoon through an opening in the top of each unit (Denoted by the green arrows on the diagram above). This air-lift action creates a very robust mixing action and eliminates the thermocline in a wastewater lagoon. An additional benefit of the mixing action is that it prevents the single cellular algae from maintaining optimal equilibrium in the water column where it is able to reproduce most rapidly. As the algae is pushed to the surface or pulled deeper into the lagoon, it begins to weaken and die off and is eventually sucked into the bio-reactors where the biology is able to consume it. The image to the right is the underside of one of the Bio-Dome units removed from the Plain City, UT installation as part of ongoing research. Please notice the streaks of green amongst the brown of the bio-film, this is the remains of algae that has been sucked into the Bio- Dome. The following pages will illustrate the effect of the Bio-Domes and Bio-Shells on the single cellular algae both visually and numerically.

3 Bio-Dome Results Plain City, UT Installation October, 2008 Plain City, UT was the first community to adopt the Bio-Domes as a means of improving the treatment capacity of their wastewater lagoons. At the time, the primary concern was increasing the treatment of the lagoons so as to avoid a multi-million dollar upgrade to an SBR plant. Even in the winter months, Plain City still sees some algae growth in their wastewater lagoons. In the summer, they experience very severe algae blooms. After installing a hanging curtain in their second cell to create a channel in which the Bio- Domes have been installed, Plain city has been able to see a visible and numerical difference in the discharge of their wastewater. The image to the left is of the Plain City, UT Public Works Director, Don Westin posing with two sample bottles collected in November The bottle on the right is a sample take just before the Bio-Domes, the sample on the left was taken right after the Bio-Domes. The visual difference is obvious, and numerically, their TSS results since installing the Bio-Domes have never been better. Archie, MO Installation October, 2011 Archie, MO installed the Bio-Domes primarily to help the city improve their lagoon s nitrification capabilities during the colder winter months in order to meet new permit limits. Archie then went on to experience one of the hottest, driest summers on record in 2012 and simultaneously experienced an algae bloom unlike any previously seen. In August 2011, Rich Lightfoot sent WCS some pictures he took of the lagoon s third cell where the Bio- Domes have been installed just prior to the final discharge of the lagoons. In the image you can see the Bio-Domes on the right, separated from the rest of cell 3 by a hanging curtain. New Castle, VA Installation April, 2012 The New Castle, VA installation is our flag ship algae removal installation. New Castle has experienced such severe algae blooms in the past that the community has seen TSS levels as high as 90 mg/l in their effluent during the late summer months of July and August. After piloting the Bio-Domes during the summer of 2011, and proving that the Bio-Dome is capable of providing the necessary treatment, New Castle opted to install the Bio-Domes in conjunction with a floating cover made from Bird Balls in the last half of their third cell. On August 15, 2012, the New Castle operators collected a sample from their wastewater lagoon that returned a TSS value of 11 mg/l. In addition to the improved water quality, utilizing the Bio-Domes instead of a sand filter saved the community in up front capital cost as well as long term O&M expenses.

4 Bio-Shell Results The Bio-Shell is a new design being developed and tested by WCS. It utilizes the exact same operation principles as the Bio-Dome but has an overall half pipe shape instead of a dome shape. The Bio-Shells are also more suited to installation in shallow lagoons that the Bio-Domes would not otherwise be applicable. Bio-Shell Pilot Study in Thomasville AL November 2010 In November 2010, WCS delivered its first mobile pilot unit to Thomasville AL, equipped with prototype Bio- Shells. The full results of the pilot study can be made available on request. Below is a summary of the results obtained with respect to TSS, where algae is a major component year round. The blue shading denotes the samples taken with a 10 day HRT, the red for samples taken with a 4 day HRT, the green for samples taken with a 2 day HRT, and the purple for samples taken with a 1 day HRT. The blue lines represent the influent sample results, the red line the effluent, and the green triangles the water temperature at the time the samples were taken. With the exception of a biological upset in June due to an unknown chemical being introduced to the lagoons by a septage hauler, the TSS levels were consistently below 15 mg/l at the longer retention times, even with the algae spikes introduced by Kevin Heartsill, the public works director, in March via 5 gallon buckets of algae from the lagoons. Once the HRT was reduced below 2 days however the biology within the Bio-Shells did not have as long to work on the TSS and the average effluent value rose to 17 mg/l with a maximum value of 25 mg/l. Even in the face of an algae bloom in the pond which caused higher TSS levels in the influent during the last four months of the study, the TSS levels never exceeded 30 mg/l in the pilot plant effluent.

5 Bio-Shell Pilot Study in Newington, GA February 2012 In February, 2012 the mobile pilot unit that was in use in Thomasville, AL was moved to Newington, GA for testing there. Newington currently has a single cell lagoon that is only 3.5ft deep and experiences significant algae blooms during the summer months. Because of other operational constraints associated with the testing, Newington kept the HRT of the pilot unit fixed at seven (7) days. As expected, the algae levels remained elevated throughout the duration of the six month study with the highest recorded influent TSS level of 94 mg / L on July 30, Regardless of the influent concentrations, the pilot unit was able to consistently return effluent TSS levels below 15 mg/l with the lowest recorded sample at 5 mg / L which was the limit of the labs accuracy. The chart below illustrates the results of the pilot study from March 2012, through August The blue line represents the influent TSS concentrations, and the red line represents the effluent TSS concentrations. As with Thomasville, the full results of the pilot study are available upon request. TSS (mg / L Influent Effluent

6 Conclusion The effectiveness of the Bio-Domes and Bio-Shells on reducing single cellular algae concentrations in wastewater lagoons is both visually apparent and numerically significant. After evaluating the performance at our various installations, WCS has come to the conclusion that as long as the bio-reactors have a minimum of 7 days to work on the algae, a reliable and significant improvement can be had in overall TSS levels and in reducing the effects of algae blooms on the water quality. When considered alongside the effective treatment of BOD and Ammonia, the WCS bio-reactors begin to display an all around value for improving the water quality of the treated effluent in a wastewater lagoon. If you are interested in learning more about WCS s bio-reactors or would like us to put together a proposal for you, please contact us using the contact information below. If you would like to speak with any of the communities mentioned in this article, please feel free to do so using the contact information found on the following page. They have all agreed to answer questions and are more than happy to their facilities. WCS Contact: Taylor Reynolds Director of Sales Wastewater Compliance Systems, Inc. taylor@wcs-utah.com (office) (cell) w.c.s.004 (skype)

7 Customer Contacts: Don Weston Plant Manager for Plain City, UT Richard Lightfoot Public Works Director for Archie MO Cell: (816) Gary Crouch Consulting Engineer with Anderson & Associates for New Castle, VA Office: (540) Kevin Heartsill Public Works Director for Thomasville, AL Brian Barrs Chief of Police / City Operations Manager for Newington, GA newops@planters.net