The aim of this thesis was evaluate the nutritive value of complete granulated dry food for adult dogs in normal activity. 17 dry feeds were choosen with regard to quality classes - 7 superpremium, 5 premium and 5 economy. Content of moisture, crude protein, crude fat, crude fibre, crude ash were determined in laboratory and NFE (nitrogen-free extracts - carbohydrates) and metabolizable energy were determined by calculations. The results of the analysis were compared with figures stated on the packaging of the feed. Quality classes were compared with each other. It was found that 12 from 17 feeds exceeded the tolerance limites for declarated nutrients. Not all of the feeds on the market is suitable for the dogs and an appellation superpremium isn't guarantee of good quality.

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Oceanografia Física, Química e Geológica, Instituto de Oceanografia, 2007. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2013-02-18T17:58:25Z No. of bitstreams: 1 2007_maicon_silva.pdf: 2073944 bytes, checksum: af385f9e57b56b200b854bc3856fc5a5 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-07-15T17:13:26Z (GMT) No. of bitstreams: 1 2007_maicon_silva.pdf: 2073944 bytes, checksum: af385f9e57b56b200b854bc3856fc5a5 (MD5) / Made available in DSpace on 2013-07-15T17:13:26Z (GMT). No. of bitstreams: 1 2007_maicon_silva.pdf: 2073944 bytes, checksum: af385f9e57b56b200b854bc3856fc5a5 (MD5) Previous issue date: 2007 / Áreas contaminadas com hidrocarbonetos tem sido um problema cada vez mais constante, uma vez que existe um grande crescimento na produção, distribuição e consumo de petróleo, principalmente nos últimos anos. Desta forma, é cada vez mais importante o conhecimento de técnicas que sejam eficientes na limpeza destas áreas. Com isso, o presente trabalho através da técnica de biorremediação buscou estabelecer qual o melhor tratamento para a remoção de contaminantes de um petróleo leve em solo arenoso. Para tanto, foram realizados dois experimentos (I e II), em que no primeiro se estudou a eficiência de remoção dos contaminantes pela utilização de três tratamentos distintos de bioestimulação (adição de nutrientes (C), adição de biossurfactante (D), adição de nutriente mais biossurfactante (E)), os quais foram comparados a dois controles, um de solo (A) e outro de atenuação natural de petróleo (B). O outro experimento serviu para verificar a eficiência da esterilização no biossurfactante utilizado, sendo utilizados um controle de solo (F), um controle de atenuação natural de petróleo (G), um tratamento com biossurfactante/nutrientes (H) e outro com biossurfactante estéril/nutrientes (I). Ao final de seis meses de estudo verificou-se que os tratamentos C e E apresentaram as melhores taxas de remoção de óleos e graxas (OG), respectivamente, 90,4 e 78%, e os melhores índices de remoção de hidrocarbonetos alifáticos: 96,82 e 98,35% e de HPAs: 83,58 e 72,3% respectivamente. Já em relação ao experimento II, concluiu-se que não houve diferenças quanto ao uso do biossurfactante estéril ou não estéril, recomendando-se no entanto, a utilização do biossurfactante estéril uma vez que desta forma não há a introdução de microorganismos estranhos ao ambiente. / Sites contaminated with hydrocarbons have been a problem more and more constant, a time that exist a great growth in the production, distribution and consumption of oil, mainly in the last years. Of this way the knowledge of techniques efficient in the cleanness of these sites is more and more important. With this, the present work through the bioremediation technique searched to establish which the best treatment for the removal of contaminantes of light oil in sandy ground. For in such a way, two experiments had been carried through (I and II), where in the first one if it studied the efficiency of removal of the contaminantes for the use of three distinct treatments of biostimulation (addition of nutrients (C), biosurfactant addition (D), addition of biosurfactant and nutrient (E)), which the two controls had been compared, one of soil (a) and another one of natural attenuation of oil (B). The other experiment served to verify the efficiency of the used biosurfactant, being used a control of soil (F), a control of natural attenuation of oil (G), a treatment with biosurfactant/nutrients (H) and another with biosurfactant sterile/nutrients (I). To the end of six months of study it can be verified that treatments C and E had presented the best ones resulted for OG, with rates of removal of 90,4 and 78% respectively. How much the Aliphatics and HPAs these had also been the best treatments with rates of removal of 96,82 and 98,35% for aliphatics and 83,58 and 72.3% for HPAs respectively. Already in relation to experiment II, it can be concluded that it doesn’t have differences how much to the use of the sterile or not sterile biosurfactant, however sends regards use to it of the biosurfactant sterile a time that of this form doesn’t have the introduction of strange microorganisms to the environment.

Organic wastes like sewage sludge and dairy manure were subjected to microwave enhanced advanced oxidation process ( MW/H₂0₂-AOP). The MW/H₂O₂-AOP was developed to release nutrients like phosphorus and nitrogen in the soluble form from the organic waste; these nutrients could be further recovered and reused. In the past, this process has been successfully applied to a series of organic waste for the purpose of solubilizing nutrients. The objectives of this research were to: (1) improve the MW/H₂0₂-AOP in terms of nutrient release by determining the different factors that influence the treatment, (2) define the factors affecting the process in their order of significance and (3) check the efficacy of the process on various waste. In the MW/H₂0₂-AOP, the role of mixing was verified, using municipal sewage sludge (aerobic and anaerobic). It was speculated that mixing the samples during the process would facilitate uniform heating and thus promote more nutrient release. At a microwave temperature of 80 °C, heating time of 5 minutes and hydrogen peroxide dosage of 1 mL per 1% of total solids, the results showed that mixed samples gave a higher nutrient solubilization compared to the unmixed. Subsequently, mixing and solids concentration were incorporated in a screening design with the other proven important factors viz., microwave temperature and hydrogen peroxide dosage. The results showed that microwave temperature and hydrogen peroxide dosage were the most significant factors for the release of orthophosphate, ammonia and soluble chemical oxygen demand. Preliminary experiments treating anaerobic sludge using MW/H₂O₂-AOP showed a decrease in orthophosphate concentration below the initial untreated value while for ammonia and volatile fatty acids the concentrations remained same as the initial. In this case, the set microwave temperature was 80 °C with 5 minutes heating and hydrogen peroxide dosage of 1 mL per 1% total solids at pH 7. To investigate this behavior, anaerobic sludge was treated at two pH conditions (7.8 and 4) at microwave temperatures ranging from 80 to 160 °C with hydrogen peroxide dosage of lmL per 1% total solids for 5 minutes. The results showed that acid addition helped in the destruction of sludge solids and release of nutrients. TheMW/H₂0₂-AOP was used to treat separated solid dairy manure. Solid dairy manure with total solids 1.6% was subjected to microwave temperature of 120 °C for 10 minutes with a hydrogen peroxide dosage of 2 mL per 1% total solids at three pH conditions (3.5, 7.3 and 12). Only at pH 3.5, substantial quantity of orthophosphate, ammonia, soluble chemical oxygen demands and volatile fatty acids could be released. Further, a screening experiment was designed including microwave temperature, hydrogen peroxide dosage and heating time, to determine the factors most affecting nutrient solubilization from solid dairy manure. Hydrogen peroxide dosage and temperature were important factors in orthophosphate release while microwave temperature and heating time were important in the release of ammonia and volatile fatty acids. The results clearly define the efficacy of the MW/H₂0₂-AOP on various organic waste as well as the conditions under which the treatment can be optimized. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

Microalgae have been recognized as one of the most promising feedstocks for biofuel production. In the Regional Algal Feedstock Testbed (RAFT) project, scientists and engineers have been working on various topics including improving cultivation strategy, optimizing culture system, developing production models, controlling contamination, and so on. One of the objectives in this project is to improve an algae cultivation model for productivity prediction and techno-economic assessment. The model adopted in this project is the Huesemann Algae Biomass Growth (HABG) model which is based upon strain characteristics obtained from laboratory experiments. However, because the model assumed optimal growth conditions for microalgae, it over-predicted biomass growth significantly when its results were compared to outdoor raceway experimental data. For example, in an attempt to control contamination, culture salinity was raised to a high level. The high salinity may limit growth of contaminants, but it also causes stress on salinity sensitive strains of microalgae. Researchers also lowered nutrient fertilization rates in order to minimize fertilizer input and cost of production. However, this introduced nutrient stress and lowered the growth rate of microalgae. In the raceways used in the RAFT project, shade covered a large fraction of the culture surface when solar angle was low. All of these growth limiting factors were not included in the original model. In this study, salinity stress, nitrogen limitation and shading effect were incorporated into the model. Growth rate reduction due to salinity stress and nitrogen limitation were quantified through laboratory experiments. An innovative concept of nitrogen availability was introduced, which estimates the nitrogen stress factor without measuring intracellular nitrogen. The shading factor was calculated based on solar position during the day and raceway geometry. The modification greatly improved the model accuracy. In addition to HABG model improvements, this study also focused on nutrient application. Several experiments were performed in both indoor and outdoor systems to improve field cultivation practices. The nitrogen experiments provided not only the growth kinetics that improved the growth model, but also demonstrated that high lipid accumulation rate was triggered at different nitrogen stress intensities for different strains. Stress should be applied depending the saturation demand of the final lipid product. In order to quickly evaluate the nitrogen status in the culture, a nitrogen stress index using optical density was proposed. Experiments in RAFT experiments supported the feasibility of applying the method in outdoor cultivation. This study also investigated maximum biomass yields of nitrogen and phosphorus for producing S. obliquus biomass with indoor bench scale experiments. The results were tested in the outdoor raceways and demonstrated the potential of using fertilizer more efficiently in microalgae cultivation.

Abstract Agriculture is the main source of nitrogen (N) and phosphorus (P), which are the nutrients accelerating the eutrophication of waters in Finland. Hence, mitigation measures are needed to reduce the nutrient loading from the arable land. Since Finland's accession to the EU in 1995 and the subsequent adaptation to its agri-environmental policy, constructed wetlands (CWs) have been one of the mitigation measures for which farmers may receive agri-environmental subsidies. The aim of this study was to find out how efficiently such CWs are able to retain the loading and how they should be designed and dimensioned in order to optimize their performance. Particular attention was paid to CW hydrology and hydraulics, since the dynamics of the water flowing through a CW is the major factor governing retention. Water quality and flow measurements were made in three CWs located in agricultural watersheds in southern Finland during 1999-2002. Hydraulic properties were examined in 2 of the CWs by simulations with 2-dimensional hydrodynamic and water quality models. According to the calculations of material fluxes, the maximum annual retention was 72% for solid material (TSS), 67% for total P and 40% for total N. The lowest retentions were slightly negative, because the CW with the smallest CW-to-watershed area ratio (0.5% in the Alastaro CW) sometimes acted rather as a source than a sink of nutrients. The highest percent retentions were found in the Hovi CW with the largest CW-to-watershed area ratio (5%). In terms of mass per CW area, the Hovi CW retained 25 kg of total P and 300 kg of total N per one hectare per one year. In the Hovi CW also dissolved reactive P retention was high (49% in situ and 34% in laboratory microcosm experiments), obviously due to high contents and low P saturation of Al and Fe oxides of the CW soil. The basic underlying reason behind the high retentions of both dissolved nutrients and particulate matter in the Hovi CW was the long water residence time coupled with high hydraulic efficiency. In the deep part of the Hovi CW, near-bottom increase of dissolved O2 was found in phase with diurnal temperature changes. The oxygen transport by this kind of convective circulation of CW water inhibited near-bottom anoxia and thus decreased the risk of P desorption. According to the hydrodynamic simulations coupled with simulated tracer tests made for the Hovi CW, a 40% improvement in hydraulic efficiency was achieved by baffles directing the main flow to optimally exploit the CW area. The rectangular, elongated shape of the Alastaro CW also showed fairly high hydraulic efficiency. Hydrodynamic simulations were also coupled with a sediment transport model, which proved to be a useful method in predicting the change of TSS concentrations in CWs. Hourly datasets of inflow and outflow revealed high attenuation of runoff peaks in the well-designed and -dimensioned Hovi CW. The hourly outflow modeled with the reservoir routing method corresponded to the observed with a reasonable accuracy. When carefully designed, painstakingly implemented and wisely located, CWs may – even in cold climate – efficiently contribute to agricultural water pollution control.

Current reclamation research following surface mining in the Appalachian coal region seeks to measure carbon (C) and nutrient accumulation and retention under forest vegetation to better understand the role of reforestation in the re-establishment of these ecosystem services. This study capitalized on the Controlled Overburden Placement Experiment (COPE), a 29-year-old reclamation research installation in southwestern Virginia, to estimate long-term mine soil C sequestration potentials and nutrient capitals after different reclamation strategies. The COPE includes two studies, a rock mix study (RM) comparing topsoil substitutes created from different ratios of local overburden [pure sandstone (SS), pure siltstone (SiS), 2:1 SS to SiS, 1:1 SS to SiS, and 1:2 SS to SiS], and a surface amendment study (SA) comparing organic amendments [control (CON), natural topsoil (TS), sawdust (SD), and 22 Mg ha-1 (22B), 56 Mg ha-1 (56B), 112 Mg ha-1 (112B) and 224 Mg ha-1 (224B) of biosolids] on a common 2:1 SS to SiS topsoil substitute. In the RM, overburden selection significantly affected soil nitrogen (N) and C concentrations as well as many other soil chemical [e.g., available phosphorus (P), pH, and other macro- and micronutrients) and physical (e.g., sand, silt and clay contents) properties.    C sequestration rates were also significantly different and ranged from 0.13 to 0.47 Mg C ha-1 yr-1. Many of the differences demonstrated relationships with the mineral make-up of the RM treatment. The SA mine soils also differed significantly in many properties after 29 years, including N, C, and many other nutrient concentrations and contents. C sequestration rates were also significantly different with the SD and 224B treatments having negative sequestration rates, and the remaining treatments ranging from 0.23 to 0.80 Mg C ha-1 yr-1. Collectively, the results demonstrate that topsoil substitutes and surface amendments show divergent trends in soil C and nutrient dynamics after nearly three decades of development and stress the importance of post- mining reclamation based on available materials and reclamation goals. / Master of Science

A dynamic, compartmental, continuously stirred tank reactor, simulation model (SET-WET) was developed for design and evaluation of constructed wetlands in order to optimize non-point source (NPS) pollution control measures. The model simulates the hydrologic, nitrogen, carbon, dissolved oxygen, bacteria, vegetative, phosphorous and sediment cycles of a wetland system. Written in Fortran 77, SET-WET models both free water surface (FWS) and sub-surface flow (SSF) wetlands and is designed in a modular manner which gives the user the flexibility to decide which cycles and processes to model. SET-WET differs from many existing wetland models in that it uses a system's approach, and limits the assumptions made concerning the interactions of the various nutrient cycles in a wetland system. It accounts for carbon and nitrogen interactions, as well as effect of oxygen levels upon microbial growth. It also directly links microbial growth and death to the consumption and transformations of nutrients in the wetland system. Many previous models have accounted for these interactions with zero and first order rate equations that assume rates are dependent only on initial concentrations. The SET-WET model is intended to be utilized with an existing NPS hydrologic simulation model, such as ANSWERS or BASINS, but may also be used in situations where measured input data to the wetland are available. The model was calibrated and validated using limited data collected at Benton, Kentucky. A non-parametric statistical analysis of the model's output indicated eight out of nine examined outflow predictions were not statistically different from the measured observations. Linear regression analysis showed that six out of nine examined parameters were statistically similar, and that within the expected operating range, all of the examined outflow parameters (9) were within the 95% confidence intervals of the regression lines. A sensitivity analysis showed the most significant input parameters to the model were those which directly affect bacterial growth and oxygen uptake and movement. The model was applied to a subwatershed in the Nomini Creek watershed located in Virginia. Two year simulations were completed for five separate wetland designs, with reductions in percentage of BOD5 (4%-45%), TSS (85%-100%), total nitrogen (42%-56%), and total phosphorous (38%-57%) comparable to levels reported by previous research. / Master of Science

Growing demand for energy worldwide has increased interest in the production of renewable fuels, with microalgae representing a promising feedstock. The large-scale feasibility of microalgae based biofuels has previously been evaluated through technoeconomic and environmental impact assessments, with limited work performed on resource requirements. This study presents the use of a modular engineering system process model, founded on literature, to evaluate the nutrient (nitrogen and phosphorus) and carbon dioxide resource demand of five large-scale microalgae to biofuels production systems. The baseline scenario, representative of a near-term large-scale production system includes process models for growth, dewater, lipid extraction, anaerobic digestion, and biofuel conversion. Optimistic and conservative process scenarios are simulated to represent practical best and worst case system performance to bound the total resource demand of large-scale production. Baseline modeling results combined with current US nutrient availability from fertilizer and wastewater are used to perform a scalability assessment. Results show nutrient requirements represent a major barrier to the development of microalgae based biofuels to meet the US Department of Energy 2030 renewable fuel goal of 30% of transportation fuel, or 60 billion gallons per year. Specifically, results from the baseline and optimistic fuel production systems show wastewater sources can provide sufficient nutrients to produce 3.8 billion gallons and 13 billion gallons of fuel per year, corresponding to 6% and 22% of the DOE goal, respectively. High resource demand necessitates nutrient recovery from the lipid-extracted algae, thus limiting its use as a value-added co-product. Discussion focuses on system scalability, comparison of results to previous resource assessments, and model sensitivity of nutrient and carbon dioxide resource requirements to system parameter inputs.

No description available.

Water management practices to reduce mass discharge are a major point of concern for aquaculture producers. This study assessed effects of consecutive low-grade weirs on chemical retention and settling of aquaculture pond effluent in a single drainage ditch. Two control and nine treatment discharges were conducted September - October 2012. Control discharge dissolved inorganic phosphorus (DIP) load increased 154%, whereas total inorganic phosphorus (TIP), ammonia, and nitrate loads decreased (47%, 43%, and 63%, respectively). Treatment discharge nutrient loads decreased across all analytes (80% DIP, 86% TIP, 89% ammonia, 89% nitrate). However, control and treatment discharges concentrations of DIP and nitrate increased, whereas TIP and ammonia concentrations decreased. All discharges reduced total and volatile suspended solid loads 72% - 94%, with removal rates of 0.02 ± 0.01 mg/L/min total and 0.02 ± 0.001 mg/L/min volatile suspended solids. Results indicate ditches fit with low-grade weirs may be an innovative management practice.