Personal summary
This past summer, I had the incredible opportunity to work under Dr. Kevin Shurtleff of the UVU chemistry department on his project to help clean out Utah Lake and harvest algae to prevent toxic algal blooms, along with three coworkers.
We worked in shifts of two, for five hours/shift, two shifts a day, five days a week. During this time, we would load up the boat with all of the necessities (propane, gas, diatomaceous earth, water, etc.) and then we would push off. Depending on where Dr. Shurtleff wanted us to harvest that day. We would motor around our home marina, the Lindon Marina, or the American Fork Marina, Utah Lake State Park, or the various recreational beaches around the east side of the lake. |
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Then we would close up the press, and continue on with the harvesting process, and then motor back to the Lindon Marina to switch shifts, or dock for the day. The algae cakes that we were able to produce were then donated to the UVU composting facility. Once the water levels in the mixing tank were right, the switch for the diatomaceous earth blower would be turned on, to add diatomaceous earth into the water. The diatomaceous earth acted as a filter aid – it binded with the algae in the water and made it able to be trapped in the filter press, so that only clean water would be expensed from the filter press. Measurements were then taken every half hour during the shift, measuring turbidity with a secchi disk, absorbency levels, surface temperature, depth, pH levels, and so on.
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Once the output valves would stop flowing water, the presses were full. We would then blow down the presses using an air compressor, to remove excess water weight. Then, we would open the hydraulic filter press, and would use plastic paddles to scrape the “algae cakes,” or pads of algae and diatomaceous earth, into bins below. After this process, we sprayed down the presses to remove any excess detritus.
The experience I gained from this job is immeasurable. I have had some experience with mechanical and wire work throughout past welding classes I have taken, but nothing compared to what I was able to learn this summer. Each day was different – which was what I loved so much about this job. Dr. Shurtleff was so willing to help share his knowledge on the subject and his project, and my coworkers and I all worked great together. We all made a noticeable difference on Utah Lake this summer thanks to Dr. Shurtleff’s invention. Upon arriving at our destination, one person would be motoring and steering the 36 foot long, 10 foot wide boat and managing the dual generators near the helm. The other worker would manage the intake pumps, diatomaceous earth blower, boom, mixing tank, and input and output valves at the front of the boat. We would begin the process by turning on both generators, lowering the intake boom at the front of the boat with the three attached intake tubes, and then flip on the switches on the breaker to begin the water intake process.
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Interview with Dr. Shurtleff
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What motivated you to start this project?
I started the project in the Fall of 2016, after Utah Lake had a bad summer of severe algae blooms. Previously, I had worked at Utah State University Research Foundation on developing large-scale algae ponds for growing large amounts of algae for conversion into biofuels. During this project, we struggled with separating the microalgae from the water (i.e. harvesting the algae). We purchased a very expensive centrifuge that didn’t work very well. Consequently after the bad summer, I decided to try and develop a better, less expensive, harvesting technique. |
How did you go about designing this project?
My students and I research a variety of filtration technologies in the literature, including chemical flocculation, vacuum filtration, centrifugation, belt presses, electrostatic belt separation, nanobubble induced flocculation, etc. We designed, built, and tested seven laboratory-scale separation/filtration technologies in the lab, before we settled on the plate and frame filtration with the addition of a filter aid. We selected this method, because large plate and frame filter presses were already available in very large sizes. We received a patent on the boat mounted plate and frame filter press with the addition of filter aid
My students and I research a variety of filtration technologies in the literature, including chemical flocculation, vacuum filtration, centrifugation, belt presses, electrostatic belt separation, nanobubble induced flocculation, etc. We designed, built, and tested seven laboratory-scale separation/filtration technologies in the lab, before we settled on the plate and frame filtration with the addition of a filter aid. We selected this method, because large plate and frame filter presses were already available in very large sizes. We received a patent on the boat mounted plate and frame filter press with the addition of filter aid
What are some of the environmental impacts that this project had on the local marinas around the area that we worked on?
If you read the statement at the end of the attached presentation, The Lindon marina manager received no toxic algae bloom warnings while we were operating in and around his marina. We did not spend as much time at the Provo marina, but I think we helped there as well as the American Fork marina and the wind surfing park just south of the Lindon marina. |
How will this impact the future of Utah Lake and the algal bloom problems?
With a single boat, we can only spot clean several prime recreational areas around the lake. Even with many boats, we could never filter the entire lake. However, every bit of algae we remove from the lake, reduces the amount of excess nutrients in the lake that foster algae blooms. Other techniques that kill the algae only release the nutrients they capture as they grow (nitrogen, phosphorus, and carbon dioxide), back into the lake for future algae blooms. Ultimately, the algae harvesting boat/boats are a temporary, short-term solution to improve the water quality on the lake in the areas where we operate. Long-term efforts to reduce nutrient addition into the lake with improved water treatment and reduced fertilizer use with less excess nutrients in run-off water will slowly, permanently, improve the lake’s water quality. In addition to these efforts, we need to enlarge the marsh areas around the lake with projects such as the Provo River Delta project and increase water flow to the lake with reduced consumption of water by communities upstream from the rivers feeding the lake. These will also improve the water quality of the lake over time. Eventually, we hope to shift the lake from a cyanobacteria dominated biomass in the water column back to benthic (bottom) growing biomass, as it was before settlement increased nutrient flows into the lake.
With a single boat, we can only spot clean several prime recreational areas around the lake. Even with many boats, we could never filter the entire lake. However, every bit of algae we remove from the lake, reduces the amount of excess nutrients in the lake that foster algae blooms. Other techniques that kill the algae only release the nutrients they capture as they grow (nitrogen, phosphorus, and carbon dioxide), back into the lake for future algae blooms. Ultimately, the algae harvesting boat/boats are a temporary, short-term solution to improve the water quality on the lake in the areas where we operate. Long-term efforts to reduce nutrient addition into the lake with improved water treatment and reduced fertilizer use with less excess nutrients in run-off water will slowly, permanently, improve the lake’s water quality. In addition to these efforts, we need to enlarge the marsh areas around the lake with projects such as the Provo River Delta project and increase water flow to the lake with reduced consumption of water by communities upstream from the rivers feeding the lake. These will also improve the water quality of the lake over time. Eventually, we hope to shift the lake from a cyanobacteria dominated biomass in the water column back to benthic (bottom) growing biomass, as it was before settlement increased nutrient flows into the lake.
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