Summer 2008 Environmental Engineering Laboratory Research
by Lt. Col. Charles Bott
The Environmental Engineering research program at VMI is being led by civil and environmental engineering professor, Lt. Col. Charles Bott. Over summer 2008 and into the fall there are seven different projects underway, funded by four external entities through VMI Research Laboratories, Inc., with a total project value for 2008 of approximately $300,000
The research group currently includes five cadets, three Virginia Tech master’s students, and one local high school student. Bott will be adding additional cadets to this team starting in September. All of the cadets earn independent research credit and are paid competitive summer and semester stipends from the research grants. Three of these cadets were involved formally in the VMI Summer Undergraduate Research Institute (SURI).
The Virginia Tech master’s students are working at VMI through a collaborative program organized by Dr. Bott whereby VMI alumni apply for graduate studies in Tech’s CEE Department. These students complete their course work in Blacksburg, but work here at VMI with Bott on their master’s thesis research project. Funding for the graduate students’ stipends and tuition is provided from research contracts.
In May, the program also welcomed its new Environmental Engineering Lab Manager, Dr. Keith Christensen. Dr. Christensen received his B.S./M.S. in botany (’79-’80) from Brigham Young University in Provo, Utah, and worked in pesticide use mapping and analyzing trace pesticides in soils and plant tissues. He received his doctorate in chemistry from UC Davis, Davis, Calif., in 2002.
Dr. Christensen is providing much needed leadership, training, and standardization in the lab, with his expertise in analytical chemistry. Keith is helping to maintain and operate laboratory instrumentation that is used to analyze environmental samples for a wide variety of constituents. His service has been invaluable with many students needing to operate sophisticated instruments to analyze a wide range of samples. Dr. Christensen keeps the instruments in top working order, trains students on their operation, and helps to ensure data quality.
Mark Miller (CE/09):
Mark Miller has been working on a project funded by FMC Corporation through Parsons Corporation on an industrial wastewater treatability study in support of remediation activities at the Avtex Fibers Superfund Site in Front Royal, Va. This project is being conducted to evaluate the treatment system planned for construction at this site that would be used to manage several concentrated leachate and contaminated groundwater streams. The entire new treatment system has been constructed in small scale in the VMI Environmental Engineering Lab to simulate what will likely be constructed in the field in a few years.
The system includes blending of two leachate feed sources, preliminary chemical oxidation using hydrogen peroxide at elevated pH, silica precipitation, a moving bed biofilm reactor (MBBR), and a sequencing batch reactor with arsenic and antimony removal. This work will produce the information required for scale-up and design of the full-scale treatment system, currently valued at approximately $15 million. Mark has been assisted in his efforts associated with constructing and operating the bench-scale treatment system by JB Bradshaw.
JB has his own project, however, that will be conducted in the field (day trips to the site) during the fall and spring semesters. This work will involve flux chamber analysis of a full-scale MBBR system currently being used to treat less concentrated leachate streams. The MBBR process is a recent retrofit from a previous biological leachate treatment process. The objective of the project is to quantify hydrogen sulfide and carbon disulfide emissions from the process.
Daniel Hingley (CE/09) and Bryce Carter (CE/09):
Daniel Hingley and Bryce Carter have been working on a project funded by the District of Columbia Water and Sewer Authority (DCWASA) in support of enhanced nitrogen removal upgrades at the 370 MGD Blue Plains Advanced Wastewater Treatment Plant in Washington, D.C. To improve nitrogen removal during winter months, Dan and Bryce have constructed, and are operating, four sequencing batch reactors that simulate the biological process used to achieve nitrification and denitrification at Blue Plains. The project objective is to evaluate the effectiveness of blending ethanol with the more commonly used external carbon source methanol to increase nitrogen removal. Blue Plains currently uses about 12,000 gallons of methanol per day and this amount will increase significantly with new nutrient removal requirements being imposed in 2013. Ethanol blending is being considered as a means of improving nitrogen removal performance during winter months both prior to 2013 and after large capital upgrades ($300 million) are made at Blue Plains.
Karen Bill (CE/07 and VT MS Student) and Celine Ziobro (CE/09)
Karen Bill and Celine Ziobro (CE/09) are also working on a project funded by DCWASA to evaluate alternative external carbon sources that could be used in place of methanol for attached growth post-denitrification processes. These and similar processes are now being considered by Blue Plains and numerous other WWTPs in the Chesapeake Bay watershed that are facing more stringent effluent nitrogen limitations.
Generally, methanol has been the carbon source of choice for enhanced nitrogen removal, but there are significant health and safety issues associated with this chemical: costs have increased dramatically in recent years; the production of methanol is tied to fossil fuel markets; and many WWTPs are looking for new alternatives. Karen constructed four bench-scale 12 L denitrifying MBBRs that are being used to degrade a simulated waste containing 10 mg/L nitrate-N.
These reactors are being operated to compare methanol, ethanol, glycerol (produced as a waste material from biodiesel plants), and sulfide. During the summer, Celine added to this system a sophisticated online analysis system that continuously measures the nitrate concentration in the feed and the effluent from all four reactors, including a UV-based nitrate probe, an automated system of solenoid valves, and a computer data acquisition system. Celine also assisted Karen with reactor operation and sampling and analysis.
Wes Thomas (CE/07 and VT MS student) and Lee Hastings:
Wes Thomas, assisted by Lee Hastings, is working on a project funded by the Hampton Roads Sanitation District (HRSD) to conduct research on nitrification kinetics as part of a 2 MGD integrated fixed film activated sludge (IFAS) process demonstration project at the 15 MGD James River WWTP. The HRSD is conducting this demonstration project to determine whether IFAS would be a suitable technology for upgrading the entire James River WWTP for biological nitrogen removal.
Wes Thomas is conducting his work in the field at the treatment plant to evaluate nitrification kinetics in four small test reactors using samples collected from the full-scale plant. Wes’ work involves complex analysis of the activity of ammonia and nitrite oxidizing bacteria derived from both suspended and attached growth (IFAS) biomass fractions and under a wide variety of experimental conditions. This work has provided a much improved understanding of how the IFAS process functions with respect to nitrification and will support the design and upgrade of this facility and numerous others considering this technology. Lee Hastings is a Rockbridge County High School student and helped Wes with his work over the summer months, and this project also includes collaboration with other graduate students at ODU and VT. Wes will have help from other cadets during the fall semester.
Phill Yi (CE/08 and VT MS student):
Phill Yi is working on a project funded by HRSD through Hazen & Sawyer, Inc., to evaluate the cause of nitrification inhibition and sporadic upsets of the biological phosphorus removal process at the Nansemond WWTP in Suffolk, Va. Phill is collecting samples at the Nansemond WWTP and several others (as controls) to evaluate the impact of several industrial dischargers and specific branches of the sewage collection system on the activity of ammonia and nitrite oxidizing bacteria and bacteria responsible for biological phosphorus removal.
Over the summer, Phill traveled to the Hampton Roads area on a weekly basis to collect samples of raw wastewater, biomass, industrial waste, and treated effluent from the WWTPs, then returning to VMI to perform experiments in four small test reactors with pH, DO and temperature control. Specifically, Phill’s objective is to pinpoint the cause of the biological process inhibition so that corrective action can occur.
The consequence of finding the cause of the problems that have been occurring at this plant for the past several years is a considerable cost savings associated with a planned upgrade of the plant for enhanced nitrogen removal. Phill’s work is continuing, but he will have some help from cadets during the fall and spring semesters.
It has been an active summer in the VMI Environmental Engineering research program at VMI with both laboratory and field projects ongoing, and it promises to be equally busy over the academic year. Thanks to the hard work and dedication of Lt. Col. Bott and his team of civil and environmental engineering cadets, alumni, and other students have the opportunity to work side by side in a state-of-the art environmental engineering research facility. The future promises to bring more projects on board and more funding for this excellent research facility.