Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Environmental Engineering
Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson
Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson
Master's Theses
Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.
In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …
Thermal Numerical Analysis Of Vertical Heat Extraction Systems In Landfills, Michael Thomas Onnen
Thermal Numerical Analysis Of Vertical Heat Extraction Systems In Landfills, Michael Thomas Onnen
Master's Theses
An investigation was conducted to determine the response of landfills to the operation of a vertical ground source heat pump (i.e., heat extraction system, HES). Elevated landfill temperatures, reported various researchers, impact the engineering performance of landfill systems. A numerical model was developed to analyze the influence of vertical HES operation on landfills as a function of climate and operational conditions.
A 1-D model of the vertical profile of a landfill was developed to approximate fluid temperatures in the HES. A 2-D model was then analyzed over a 40 year time period using the approximate fluid temperatures to determine the …