Performing Department
(N/A)
Non Technical Summary
Water-born pollution, in the form of excessive nitrates, phosphates, an organic carbon--often called nutrient pollution--is a growing problem in the US and, globally. Once these nutrients find their way to lakes and rivers, they can lead to an overgrowth of algae. The consequence of "algae-blooms" often include the formation of oxygen-depleted "dead-zones" and the release of toxic compounds, which can make the water hazardous to fish, animals, and humans alike.Fortunately, algae can also be part of the solution. By cultivating algae in contained bioreactors, the excess nutrients, which are commonly found in municipal wastewater, can be removed prior to the effluent's release. Furthermore, this method of nutrient recovery is superior to conventional processes because it avoids the use of costly chemical additives and it allows the nitrogen component of the wastewater to be converted into algal biomass, rather than being wasted with the release of N2 gas. When the algae is harvested from the bioreactors, it can be de-watered, dried, and sold for various uses, such as fertilizer, feeds for animals and aquaculture, and as feedstock for biofuel production.The proposed project will focus on the construction and testing of novel photobioreactor technology that will allow algae to be easily cultivated at municipal wastewater treatment facilities. Because the reactor utilizes a clear, plastic barrier for process containment, the risk of culture contamination is greatly reduced. With improved culture protection, desirable algae strains capable of making unique and valuable products are more easily cultivated.The Phase I project will involve a proof-of-concept demonstration using the wastewater from a small community farm. A pilot-scale system will be constructed and tested using a live algae culture. System parameters will be optimized in order to maximize the level of nutrient removal and the quantity of algae biomass produced. A detailed social-science plan and community education program will promote improved economic and social sustainability of the technology.If the technology can be commercialized, it will provide municipalities with a more cost-effective option for removing nutrient pollution from their treated wastewater stream, leading to improved aquatic health in surrounding waters. With the ability to produce high-value algae co-products, wastewater treatment facilities can stimulate economic growth in the community and expand the nation's resources for renewable bioproducts.
Animal Health Component
50%
Research Effort Categories
Basic
(N/A)
Applied
50%
Developmental
50%
Goals / Objectives
Objective 1 - Create a CFD model of the TriPARTM system:Objective 2 - Perform tracer study in the TriPARTM using Rhodamine dye:Objective 3 - Set-up and commission TriPARTM to run as a PFR with Product Recycle:Objective 4 - Run TriPARTM system as PFR with live algae culture:Objective 5 -Perform a Techno-economic Analysis for using the TriPARTMsystem for wastewater treatment:
Project Methods
Objective 1: A Computational Fluid Dynamics model (CFD) will be performed to evaluate the flow dynamics in the TriPAR system. This work will be contracted out, and the model will be created using COMSOL software.Objective 2: Rhodamine Trials - To validate the results from our modeling work, we will perform a tracer experiment using a Rhodamine dye, injected at the inlet of the TriPARTM system. We will continue to flow fresh water into the system at 130 LPM and track the progression of the dye along the length of the TriPARTM. We will confirm the residence time as the dyed solution makes its way to the effluent side of the reactor, and take samples of the dyed solution to determine the distribution of the dye during its transit from the inlet to the outlet. We will rely on visual observation, spectrophotometric analysis of effluent, and possible salinity measurements. Flow rates will be measured using an ultra-sonic digital flow meter.Objective 3:Incorporation of process controltechnologies, such as a turbidity meter, flow sensor, and variable speed pump, to control flow rate and algae density at the TriPARTM inlet and outlet, will be done via a ModBUS TCP protocol, to communicate between 3rd party technologies and the HAICUTM system. Nutrient dosing pumps will be used to inject nutrients at the inlet end of the TriPARTM system, and a nutrient sensor (QBI-QUBE) will be used at the inlet and outlet streams, to confirm the inlet concentration and subsequent nutrient drawdown rates. These will be verified with labassays to confirm inlet and outlet concentrations of N and P.Objective 4: Scale-up utilizing existing seed train infrastructure available at our research facility will utilize standard algal culturing techniques and a modified F/2 media with acetate for mixotrophic growth. Once the 55,000L TriPAR system is inoculated, the nutrient draw down trial will begin. Samples will be collected at 1-2 hr intervals from both inlet and outlet streams, cell density will be assessed using a spectrophotometer at 440 nm, and correlated to dry weight by filtering a knownvolume of culture across a pre-weighed glass fiber filter, and then drying the filter in a moisture analyzer and re-weighing. Samples will also be filter sterilized, to remove any biomass, and analyzed for N and P. These sampleswill be used to correlate with the nutrient draw-down rates provided by the QUBE sensor.Objective 5: To develop a detailed techno-economic analysis of the proposed process, we will incorporate thetechnical design data gathered from the experimental trials performed, andmake use of special TEA software and standardized templates available from the US National Renewable Energy Lab.Objective 6: To generate a communication protocol between HAICUTM, and the Liqoflux Ultrafiltration (UF) system, and QBI- QUBE sensor, will require electrical engineering to ensure that there is compatible communication between the Liqoflux and QBI systems and the Pure Biomass HAICUTM. To do so, we will rely on a Modbus TCP communication protocol, and link all three systems to an Allen Bradley PLC which will act as the central control interface for the three technologies.