Reducing organic loading of anaerobic lagoons with high-rate anaerobic digestion : reactor performance and economic analysis

This research examined the potential of reducing dairy waste lagoon organic loading with high-rate anaerobic digestion (HRAD) systems operating at hydraulic retention times (HRT) of less than one day. An in-line approach was examined as a means of pre-treating the wastestream to reduce the lagoon organic load. An off-line approach was examined as a means to reduce the organic load within the anaerobic lagoon through the removal of volatile fatty acids. Two types of HRADs were tested, an anaerobic sequencing batch reactor (ASBR) and a downflow anaerobic filter (DFAF), both of which operated at 25 and 35° C. Initial plans were to use the HRADs for removal of organics by operating upstream of anaerobic lagoons. However, initial results of this approach were unsatisfactory, and it was suspected that the reactors were removing organic materials through settling rather than biodegradation. This possibility was tested by performing a chemical oxygen demand (COD) mass balance to determine if suspended solids settling was the main method of wastewater treatment. The mass balance demonstrated that 100% of the COD removed in the ASBRs, and 72% of the COD removed in the DFAFs, could be attributed to settling instead of biodegradation. The second experiment demonstrated that volatile fatty acids (VFA), mainly acetic (HAc), could be removed from the anaerobic lagoon if an HRAD was used in an off-line mode. Off-line operation would involve pulling HRAD influent from below the lagoon surface with the effluent being returned to the lagoon. At low loading rates (1.0 and 3.0 kg HAc m-3 d-1), both reactor types had treatment efficiencies greater than 30%. At the lowest loading there was no difference among the reactor types at the same temperature (P \u3e 0.33 for both temperatures). At the higher loading, there was a difference across reactor types at the same temperature (P \u3c 0.0001 for both temperatures). At a loading of 6.0 kg HAc -3 d-1 the ASBRs proved to be ineffective; whereas, the DFAJFs had removal efficiencies \u3e 70% for both temperatures. The DFAFs also provided \u3e 40% removal of HAc at loading rates of 24 kg HAc -3 d-1; thereby, suggesting that DFAFs are superior to ASBRs for removing accumulated VFAs at high loading rates. The high removal rates at the low HRTs allow for a smaller volumetric reactor and thereby a more feasible system. An economic model was developed to explore the feasibility of installing a DFAF system compared to expanding an existing anaerobic lagoon. The model computed the equivalent annualized annuity (EAA) of the two alternatives with a DFAF reactor operating at 0.8 kg HAc -3 d-1 and 2.4 kg HAc -3 d-1. The model was run for herd sizes ranging from 100 to 800 cows and overloads ranging from 10 to 100%. The results of the model suggests that for facilities with small herd sizes (\u3c 400 cows) and overloads less than 70%, expanding the lagoon is the preferred alternative. With large herd sizes (\u3e 400 cows) and overloads greater than 70%, the DFAF was suggested to be the preferred alternative

A History of the Pickles Gap Baptist Church

The purpose of this thesis was to gather and to get in readable form information on the origin, life, personalities, and developments of the Pickles Gap Baptist Church in Faulkner County, Arkansas. The procedure took four lines: (1) a summary history from around 1878 to the present by families, (2) a review of the organizational and functional development, (3) a listing of family contributions to the work of the church, and (4) a resume of contributions by pastors. The church began in 1878 as the Sulphur Springs Baptist Church. In 1921 the name was changed to Pickles Gap Baptist Church because there were at that time two churches by the old name in the Greenbrier Baptist Association. In the early years, the church was a quarter-time pastorate. It became a full-time pastorate in 1952. Three houses of worship have been built by the church, the present one being built in 1945. The unified budget plan of finance was developed under the Reverend T.W. Hayes\u27 leadership. The organizational development was slow and gradual. The church in 1964 has the four conventional church organizations: Sunday School, Training Union, Women\u27s Missionary Union, and Brotherhood. Such a study of the Pickles Gap Baptist Church is particularly significant this year because it comes during the Baptist Jubilee Advance devoted to Baptist Heritage

Cooled Infrared Dichroic Beamsplitters and Filters for the MIRI Spectrometer and Imager (5-29µm)

The spectral design and fabrication of cooled (7K) mid-infrared dichroic beamsplitters and bandpass filter coatings for the MIRI spectrometer and imager are described. Design methods to achieve the spectral performance and coating materials are discussed

Determination of the embedded thermo-optical expansion coefficients of PbTe and ZnSe thin film infrared multilayers

This paper reports the first derived thermo-optical properties for vacuum deposited infrared thin films embedded in multilayers. These properties were extracted from the temperature-dependence of manufactured narrow bandpass filters across the 4-17 µm mid-infrared wavelength region. Using a repository of spaceflight multi-cavity bandpass filters, the thermo-optical expansion coefficients of PbTe and ZnSe were determined across an elevated temperature range 20-160 ºC. Embedded ZnSe films showed thermo-optical properties similar to reported bulk values, whilst the embedded PbTe films of lower optical density, deviate from reference literature sources. Detailed knowledge of derived coefficients is essential to the multilayer design of temperature-invariant narrow bandpass filters for use in non-cooled infrared detection systems. We further present manufacture of the first reported temperature-invariant multi-cavity narrow bandpass filter utilizing PbS chalcogenide layer material

Spectral design of temperature-invariant narrow bandpass filters for the mid-infrared

The ability of narrow bandpass filters to discriminate wavelengths between closely-separated gas absorption lines is crucial in many areas of infrared spectroscopy. As improvements to the sensitivity of infrared detectors enables operation in uncontrolled high-temperature environments, this imposes demands on the explicit bandpass design to provide temperature-invariant behavior. The unique negative temperature coefficient (dn/dT<0) of Lead-based (Pb) salts, in combination with dielectric materials enable bandpass filters with exclusive immunity to shifts in wavelength with temperature. This paper presents the results of an investigation into the interdependence between multilayer bandpass design and optical materials together with a review on invariance at elevated temperatures

College Football: Doing Less With More and More With Less

There is a substantial and highly significant correlation between the performance of widely followed college football teams and the pre-college recruiting scores received by their players. This correlation implies a regression toward the mean that should be taken into account in the identification of under-performing and over-performing teams and can also be used to improve pre-season predictions of the performance of teams with highly rated and lowly rated recruits

Cooled optical filters for Q-band infrared astronomy (15-40 μm)

With a growing interest in mid- and far-infrared astronomy using cooled imaging and spectrometer instruments in high-altitude observatories and spaceflight telescopes, it is becoming increasingly important to characterise and assess the spectral performance of cooled multilayer filters across the Q-band atmospheric window. This region contains spectral features emitted by many astrophysical phenomena and objects fundamental to circumstellar and planetary formation theories. However extending interference filtering to isolate radiation at progressively longer wavelengths and improve photometric accuracy is an area of ongoing and challenging thin-film research. We have successfully fabricated cooled bandpass and edge filters with high durability for operation across the 15-30 µm Q-band region. In this paper we describe the rationale for selection of optical materials and properties of fabricated thin-film coatings for this region, together with FTIR spectral measurements and assessment of environmental durability

Comparing and Contrasting a Program versus System Approach to Evaluation: The Example of a Cardiac Care System

This paper focuses on the application of systems thinking concepts to evaluate systems. &nbsp;The terms systems and systems thinking concepts are first defined.&nbsp; The use of systems thinking concepts in program and system evaluation are then highlighted.&nbsp; It is noted that while there are methods available to assist evaluation practitioners in applying systems thinking concepts to program evaluation, there is a need for similar guidance in applying systems thinking concepts to evaluating systems.&nbsp; System Evaluation Theory (SET) is then reviewed as one evaluation theory designed to apply systems thinking concepts to evaluating systems. A case illustration is presented to help teach practitioners how to apply SET’s three steps.&nbsp; The discussion focuses on comparing the differences between evaluation questions answered by applying systems thinking concepts versus those using program logic models

Genome sequence of the Bacteroides fragilis phage ATCC 51477-B1

The genome of a fecal pollution indicator phage, Bacteroides fragilis ATCC 51477-B1, was sequenced and consisted of 44,929 bases with a G+C content of 38.7%. Forty-six putative open reading frames were identified and genes were organized into functional clusters for host specificity, lysis, replication and regulation, and packaging and structural proteins