produced confluence poster vfinal
TRANSCRIPT
ResultsIntroductionExtraction of oil and gas in Utah’s Uintah Basin results in large quantities of wastewater, or produced water, with nutrients and residual organic chemical that represent a significant resource for producing energy-related and value added products. Produced water was obtained from industries operating in Utah’s Uintah Basin. The goal of the project was to demonstrate the production of biocrude and the treatment of produced water using naturally occurring microalgae.
• Rotating Algal Biofilm Reactor (RABR) consisting of 23 polystyrene disks
• Suspended over raceway containing produced water and algae grows as a biofilm
• Motor continuously rotates disks which are half submerged
Produced Water
• Within the Uintah Basin (defined as Uintah and Duchesne Counties within Utah) approximately 93 million barrels of water were produced in 2013
• Only 11% of the water was disposed of through evaporation with the national average at 2%. The rest is reinjected into the subsurface
Reactor Water Treatment
Utah produced water lagoon (image: Marc Silver)
Bioenergy from Produced Water Contact: [email protected]
Ben Peterson, Jordan Wanlass, Jay Barlow, Dr. Jason Quinn, and Dr. Ron Sims
Biocrude Production
Future Work
Rotating algal Biofilm Reactor (RABR) utilizing polystyrene to cultivate algae
Hydrothermal Liquefaction (HTL) Unit for biocrude conversion
Biocrude oil produced from microalgae cultivated on produced water
• Wet algal biomass is converted at high temperature and high pressure in a hydrothermal liquefaction reaction (HTL)
• HTL operating conditions: Temperature: 325 °C Pressure: 14 MPa (2000 psi) Retention time: 60 min
• HTL produces four products: Biocrude (energy product) Gas (energy product) Aqueous (fertilizer product) Solids
• Biocrude chemical composition and energy content are comparable to petroleum crude
• A yield of 35% ash free dry weight was obtained in laboratory HTL tests and 58% of feedstock energy was recovered in the biocrude
• Biocrude can be refined into an array of drop-in renewable fuels
BIOCRUDE
RENEWABLE DIESEL
RENEWABLE GASOLINE
Biocrude can be reined into different renewable fuels
• A techno-economic and life-cycle assessment of biofilm growth of microalgae was conducted
• It demonstrated that integrating microalgae cultivation with wastewater treatment significantly reduces environmental impact
• Additionally microalgae productivity significantly affects fuel selling price.
• A lower selling price increases viability for biocrude to be converted into renewable fuels to compete with traditional fossil fuels
Polystyrene disk RABR for side by side comparisons
• Incorporate additional row of disks for side by side comparison
• Optimize the system according to techno-economic and life-cycle assessment by: Reducing rate of rotation to
decrease energy requirements Increasing the productivity of
the microalgae by adding more nutrients and/or other easilymetabolized organic carbon sources
• Produced wastewater was treated by augmenting the waste with LLC2, a cyanobacteria isolated from the Logan Municipal Treatment Lagoons.
• Objectives include reducing COD of produced wastewater by culturing cyanobacteria (LLC2) in heterotrophic conditions
• Along with testing for heterotrophic growth, differences between aerobic and anaerobic conditions were tested for significance
• A 45% reduction in COD from untreated waste at 6600 mg/L was seen in aerobic, non-autoclaved samples augmented with LLC2
• Only a 40% reduction in COD was exhibited for samples not augmented with LLC2
• Aerobic conditions show significant improvement over anaerobic conditions for the treatment of produced wastewater
• Testing the heterotrophic characteristic of LLC2 on a RABR, namely "Night RABR”
Cyanobacteria (LLC2) cultured in heterotrophic conditions to reduce COD of
produced water
Characterization of Produced Wastewater by Hach 8000 Protocol.