Existing and proposed regulations requiring organic waste diversion from landfills, as well as public interest, are driving an ever-increasing need for sustainable waste management technologies for handling organic wastes. Diverted organic wastes are often composted however, composting alone does not harness the renewable energy generation potential of organic wastes, and in many cases there is not a large enough demand for composted solids to justify these programs. Alternatively, anaerobic digestion (AD) can be employed for bioenergy generation, and digestate can be subsequently composted to generate marketable soil amendments. A recently conducted life cycle assessment demonstrated that AD represents the most environmentally sustainable waste management technology for food waste.
Upon completion of this course, the attendee will be able to:
- Describe digester performance
- Discuss biogas applications including electricity production and combined heat and power, purification and injection into natural gas pipelines and its use as a transportation fuel
- Demonstrate the elements of post-digestion composting and nutrient recovery
- Describe steps for sustainability and AD
- Discuss the economics of AD for municipal solid waste (MSW)
SUSAN K. DE LONG, Ph.D. has served, since 2009, as a faculty member at Colorado State University (CSU), where she has been conducting research focused on biological conversion of wastes to energy and bioremediation processes. Her area of expertise is in environmental biotechnology and applied molecular biology. She obtained bachelors degrees in Environmental Science and Molecular and Cell Biology from the University of California at Berkeley and subsequently obtained her masters and doctorate in Environmental Engineering from The University of Texas at Austin. Her masters and doctoral research was focused on development of biotreatment processes for application to hydrocarbon and perchlorate contamination, as well as on the development and application of molecular biology assays to guide development of these biotechnologies. Dr. De Long’s recent work has been focused on development of specialized microbial cultures for hydrolysis of organic wastes that are capable of rapid waste conversion under non-ideal conditions, such as in the presence of the microbial inhibitors ammonia and salinity. She utilizes molecular biology tools to guide development of such advanced microbial cultures and for the development of advanced anaerobic digestion technologies designed to increase biogas production from municipal and agricultural wastes. Dr. Susan De Long is joining the Department of Civil and Environmental Engineering this Fall Semester as Assistant Professor. Her area of expertise is environmental biotechnology. She was born and raised in the city of Los Angeles, California where she observed the negative impacts of human activities on the environment from a young age and decided to pursue a career working to address environmental issues. Dr. De Long obtained a bachelor’s degree from the University of California at Berkeley in Environmental Science. While at UC Berkeley, she discovered a fascination with molecular biology because she loved learning about the molecular-scale processes that allow living organisms to function. Hence, she decided to pursue a second bachelors’ degree in molecular and cell biology.
SYBIL SHARVELLE, Ph.D. has served as a faculty member at Colorado State University (CSU) since 2007 with research on anaerobic digestion for methane capture and use. Her expertise is in the area of biological process engineering. While pursuing a M.S. degree at the University of Colorado Boulder, she worked on a project funded by NASA to develop a biological processor for treatment of urine-soap wastewater expected to be generated at the International Space Station. This research led Dr. Sharvelle to the Ph.D. program at Purdue University where she was part of the NASA Specialized Center for Research and Training (NSCORT) focused on advanced life support (ALS) research. The goal of center was to recycle valuable resources such as water and air, while recovering important nutrients. Her specific project was a biological processing unit for simultaneous treatment of graywater (laundry and hygiene wastewater) and waste gas contaminated with high levels of ammonia and hydrogen sulfide. Dr. Sharvelle’s previous research experience in closed loop life support led her to research in the area of sustainable water and waste management. Dr. Sharvelle was hired by CSU to provide expertise and serve as an extension specialist in the area of livestock waste management. She has developed an online decision tool for feasibility of on-farm anaerobic digestion. She is also developing a new technology for anaerobic digestion of dry waste, including municipal and agricultural wastes, which would improve the feasibility of waste conversion to methane biogas. Dr. Sybil Sharvelle has nine years of experience working on graywater projects. Her graduate studies were funded by NASA to optimize biological waste processing systems that would treat graywater with the end goal of potable reuse. The waste treatment concept employed entailed separate source collection and treatment of graywater, urine, and fecal material. Dr. Sharvelle’s experience in closed loop recycling of resources is very valuable for implementation of sustainable development concepts for urban water management. Dr. Sharvelle is currently working on sustainable urban water management including graywater reuse, reclaimed water reuse, development of models to estimate water savings associated with urban water conservation practices. Dr. Sharvelle also has several years of experience working on waste conversion to methane through anaerobic digestion.