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You searched for +publisher:"University of Vermont" +contributor:("Drizo, Aleksandra"). Showing records 1 – 2 of 2 total matches.

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University of Vermont

1. Twohig, Eamon. Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate.

Degree: MS, Plant and Soil Science, 2012, University of Vermont

Treating elevated nutrients, suspended solids, oxygen demanding materials, heavy metals and chemical fertilizers and pesticides in agricultural wastewaters is necessary to protect surface and ground waters. Constructed wetlands (CWs) are an increasingly important technology to remediate wastewaters and reduce negative impacts on water quality in agricultural settings. Treatment of high strength effluents typical of agricultural operations results in the production of methane (CH4), a potent greenhouse trace gas. The objective of this study was to evaluate CH4 emissions from two subsurface flow (SSF) CWs (223 m2 each) treating dairy wastewater. The CWs were implemented at the University of Vermont Paul Miller Dairy Farm in 2003 as an alternative nutrient management approach for treating mixed dairy farm effluent (barnyard runoff and milk parlor waste) in a cold, northern climate. In 2006, static collars were installed throughout the inlet, mid and outlet zones of two CWs (aerated (CW1) and a non-aerated (CW2)) connected in-series, and gas samples were collected via non-steady state chambers (19.75 L) over a nine-month period (Feb-Oct 2007). Methane flux densities were variable throughout the nine-month study period, ranging from 0.026 to 339 and 0.008 to 165 mg m-2 h-1 in CW1 and CW2, respectively. The average daily CH4 flux of CW1 and CW2 were 1475 and 552 mg m-2 d-1, respectively. Average CH4 flux of CW1 was nearly threefold greater than that of CW2 (p = .0387) across all three seasons. The in-series design may have confounded differences in CH4 flux between CWs by limiting differences in dissolved oxygen and by accentuating differences in carbon loading. Methane flux densities revealed strong spatial and seasonal variation within CWs. Emissions generally decreased from inlet to outlet in both CWs. Average CW1 CH4 flux of the inlet zone was nearly threefold greater than mid zone and over tenfold greater than flux at the outlet, while fluxes for CW2 zones were not statistically different. Methane flux of CW1 was nearly fifteen fold greater than CW2 during the fall, representing the only season during which flux was statistically different (p = .0082) between CWs. Fluxes differed significantly between seasons for both CW1 (p = .0034) and CW2 (p = .0002). CH4 emissions were greatest during the spring season in both CWs, attributed to a consistently high water table observed during this season. Vegetation was excluded from chambers during GHG monitoring, and considering that the presence of vascular plants is an important factor influencing CH4 flux, the potential CH4 emissions reported in our study could be greatly underestimated. However, our reported average CH4 fluxes are comparable to published data from SSF dairy treatment CWs. We estimate average and maximum daily emissions from the entire CW system (892 m2) at approximately 1.11 and 6.33 kg CH4 d-1, respectively, yielding an annual average and maximum flux of 8.51 and 48.5 MtCO2-e y-1, respectively. Advisors/Committee Members: Drizo, Aleksandra.

Subjects/Keywords: Methane; Constructed wetlands; agricultural wastewater

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Twohig, E. (2012). Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate. (Thesis). University of Vermont. Retrieved from https://scholarworks.uvm.edu/graddis/231

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Twohig, Eamon. “Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate.” 2012. Thesis, University of Vermont. Accessed November 12, 2019. https://scholarworks.uvm.edu/graddis/231.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Twohig, Eamon. “Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate.” 2012. Web. 12 Nov 2019.

Vancouver:

Twohig E. Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate. [Internet] [Thesis]. University of Vermont; 2012. [cited 2019 Nov 12]. Available from: https://scholarworks.uvm.edu/graddis/231.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Twohig E. Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate. [Thesis]. University of Vermont; 2012. Available from: https://scholarworks.uvm.edu/graddis/231

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Vermont

2. Bird, Simon. Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse.

Degree: MS, Plant and Soil Science, 2009, University of Vermont

Around the world, the eutrophication of freshwater lakes and streams by the excess loading of phosphorus (P) has become one of the most important water quality issues. In Vermont, P pollution from urban and agricultural non-point sources has led to severe blooms of toxic cyanobacteria in Lake Champlain, and the degradation of the lake’s value as a drinking water source and its recreation potential. Electric arc furnace (EAF) steel slag has been identified as an effective material for use as a filter media for the removal of P from both point and non-point sources of pollution. In order to further assess the feasibility of this technology for use in Vermont, several investigations were carried out starting in the winter of 2006. Three objectives for research were identified: 1) to construct 2 EAF steel slag filters in-series at the Constructed Wetlands Research Center (CWRC) and investigate their efficiency in P, TSS and metals reduction from dairy waste water in a cold climate; 2) investigate the potential for reuse of P saturated EAF steel slag as a soil amendment and plant fertilizer by testing bioavailability of sorbed P and quantities of P released to surface runoff; 3) To elucidate the principal mechanisms responsible for the removal of P in EAF slag filters when used for the treatment of dairy effluent. The results indicated that 2 EAF steel slag filters constructed in-series are an effective method to increase the treatment efficiency and longevity of a filter system. Additionally, parameters for the concentrations of total suspended solids (TSS) and biological oxygen demand (BOD) were developed, both important factors for design of filter systems. In greenhouse trials, Medicago sativa plants achieved greater above ground biomass growth with P fertilization by triple super phosphate (TSP) than EAF steel slag at the shorter growth period (5 weeks). However, by the end of the longer growth period (10 weeks) except at the highest amendment rate, the plants treated with EAF steel slag had a higher growth rate than the TSP, suggesting that EAF steel slag is an effective slow release P source. Using a rain simulator, the amount of P lost to surface runoff from both a saturated and a semi-saturated EAF steel slag was found to be negligible, and except for total P in the saturated slag, to be below 1 mg L-1. Voltammetric analysis and geochemical modeling were used to identify possible mechanisms for the removal of P from waste effluent. The Ca mineral hydroxyapaptite and the Fe(II) mineral vivianite were both shown to be likely mechanisms given the chemical conditions in EAF steel slag filters. This research represents the first investigation of cold weather performance of EAF steel slag filters for the treatment of dairy parlor and milk house waste effluent. Additionally, it was also the first research on the bioavailability of P sorbed to EAF steel slag, and of the possibility of its reuse as a soil amendment, and of the mechanisms involved in P removal from dairy waste effluent. Advisors/Committee Members: Drizo, Aleksandra.

Subjects/Keywords: electric arc furnace slag; phophorus

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Bird, S. (2009). Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse. (Thesis). University of Vermont. Retrieved from https://scholarworks.uvm.edu/graddis/24

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Bird, Simon. “Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse.” 2009. Thesis, University of Vermont. Accessed November 12, 2019. https://scholarworks.uvm.edu/graddis/24.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Bird, Simon. “Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse.” 2009. Web. 12 Nov 2019.

Vancouver:

Bird S. Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse. [Internet] [Thesis]. University of Vermont; 2009. [cited 2019 Nov 12]. Available from: https://scholarworks.uvm.edu/graddis/24.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bird S. Investigations of Electric Arc Furnace Slag Filters: Phosphorus Treatment Performance, Removal Mechanisms and Material Reuse. [Thesis]. University of Vermont; 2009. Available from: https://scholarworks.uvm.edu/graddis/24

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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