Estudos foram desenvolvidos para dimensionar e adaptar o injetor do queimador principal de um aquecedor de água tipo acumulação de 75 L. O diâmetro do injetor foi redimensionado em função da pressão de serviço de 100 mm H2O e poder calorífico inferior do biogás de 21.600 kJ m-3 n, garantindo a manutenção da potência calorífica do equipamento de 20.900 kJ h-1. Os resultados demonstraram que o queimador adaptado operou com biogás adequadamente, com chama estável. A eficiência média do aquecedor foi de 68%, para ganho térmico de 36,7 ºC, correspondendo à temperatura final da água igual a 62,7 ºC, sendo consumido 0,796 m³n de biogás, aquecendo 75 L de água em 72 minutos.<br>Studies had been developed to project and to adapt the injector of the main burner of water heater accumulated type of 75 L. The diameter of the injector was project in function of the pressure of service of 100 mm H2O and inferior calorific power of biogas of 21,600 kJ m-3 n, having guaranteed the maintenance of the calorific power of the equipment of 20,900 of kJ h-1 .The results had demonstrated that the adapted burner to operate with biogas operated adequately with a steady flame. The average efficiency of the heater was of 68%, for a thermal profit of 36.7 ºC, corresponding the final temperature of the water of 62.7 ºC being consumed 0.796 m³ n of biogas, heating 75 L of water in 72 minutes.

RESUMEN. El objetivo del presente estudio fue analizar los niveles de plomo (Pb), cadmio (Cd), aluminio (Al), zinc (Zn), cobre (Cu) y cromo (Cr) en agua de bebederos de presión distribuidos en el Campus de la Universidad de San Paulo, Ribeirão Preto, Brasil. Fueron colectadas 30 muestras aleatoriamente obtenidas en diferentes instancias del Campus y analizadas por Espectrofotometría de Absorción Atómica. De acuerdo con la Guía de Valores Máximos Recomendados de la Organización Mundial de la Salud (OMS), plomo, cadmio y zinc se detectaron en concentraciones superiores a las recomendadas en 40%, 20% y 13% de las muestras, respectivamente. Los resultados son analizados considerando aspectos nutricionales y toxicológicos, referente a la presencia de metales esenciales y tóxicos para el hombre. Comparando los límites reglamentados en diez países de América, se pone de manifiesto la necesidad de un consenso en el establecimiento de las concentraciones máximas de metales en agua potable. La Ingesta Diaria Tolerable, debe ser la base para el establecimiento del nivel máximo de metales en agua, con la finalidad de prevenir la aparición de enfermedades asociadas a largo plazo.<br>SUMMARY. The purpose of this study was to analyze the levels of lead (Pb), cadmium (Cd), aluminum (Al), zinc (Zn), cooper (Cu) and chromium (Cr) in the water of drinking fountains distributed in the Campus of the University of São Paulo, Ribeirão Preto, Brazil. Thirty random samples were collected in different parts of the Campus that were analyzed by Atomic Absorption Spectrophotometry. According to WHO’s Drinking Water Guidelines; lead, cadmium and zinc were found in concentrations higher than those recommended in 40%, 20% and 13% of the samples, respectively. The results were analyzed considering nutritional and toxicological aspects related to the presence of essential and toxic elements for the human being. Reviewing the regulatory limits established in ten countries of America, authors focus in the necessity to find a consensus in the establishment of the higher levels of heavy metals in potable water. The tolerable daily intake, have to be the basis to assure the prevention of diseases associated with a long-term ingestion of these elements through foods.

Se utilizaron 22 cerdos machos y hembras en iguales proporciones de 17.5 kg de peso vivo promedio distribuídos de acuerdo a un diseño de clasificación simple en dos tratamientos y 11 réplicas. Los tratamientos experimentales consistieron en: I-Suministrarles a los cerdos agua de beber normal y II- Suministrarles agua tratada magnéticamente (T.M.A) a 2542 gauss y una velocidad de flujo de 1 m/s, para estudiar la influencia que ejerce el agua tratada magnéticamente sobre los principales rasgos de comportamiento de los cerdos en ceba alimentados con dietas basadas en miel B y harina de soya. No se encontraron diferencias significativas entre tratamientos para los pesos finales (kg), ganacias de peso (g/día), consumo MS (kg) y conversiones alimentarias (kg MS/kg aumento) siendo sus valores de 96.70 y 95.70; 727 y 719; 3.0 y 3.0; 4.15 y 4.14 respectivamente. No se observó efecto sobre el comportamiento animal al utilizar agua tratada magnéticamente a los niveles de inducción y flujo empleado en esta prueba. | Twenty two male and female pigs with 17,5 kg live weight as average were distributed according to a single classification in two treatments and 11 replications. The experimental treatments consist in: I- suppling normal drinking water to the pigs and IIMagnetical 2542 gauss treated water and a speed flow 1 m/s, in order to study the influence of magnetical treated water on the main trait performance of fattening pigs fed with diets based in type B molasses and soy bean meal. No significant differences were found betwen treatments for the final weight (kg), daily gains of weight (g/day), feed intake of DM (kg) and feeding conversions (kg DM/kg gains). The values were: 96,70 and 95,70; 727 and 719; 3,0 and 3,0; 4,15 and 4,14 respectively. No effect was encountered in the use of magnetical treated water under the parameter probed in this trial.

Temperature affects the physical, chemical and biological processes involved in the transport of drinking water, conditioning its water quality. Different works have revealed the role of this variable in specific phenomena. At the same time, research has been carried out to characterize temperature behaviour in water supply systems and assess its modelling possibilities. All of them are independent contributions, but there is not a global and joint vision about the role of temperature in the behaviour of a water network, even though this variable is one of those that will be most affected by climate change. The aim of this work is to revise the importance of water temperature in the different processes that occur during water distribution and to compile what is known so far about temperature modelling in water supply systems. This literature review highlights the importance of thermal conditions in the different dynamics within a distribution network, detecting a need to improve knowledge about its behaviour. This is important not only to better understand water quality at present, but also to evaluate the potential complications that may arise in future climate change scenarios. | La temperatura afecta a los procesos físicos, químicos y biológicos involucrados en el transporte del agua potable, por lo que condiciona la calidad del agua suministrada. Diferentes trabajos han puesto de manifiesto el papel de esta variable de modo específico en cada proceso o fenómeno. A su vez, se han desarrollado investigaciones sobre el comportamiento de la temperatura en las redes de agua y las posibilidades para su modelización. Todas ellas son contribuciones independientes, pero no se cuenta con una visión global y conjunta del papel de la temperatura en el comportamiento de una red de distribución, aun cuando esta variable es una de las que más se verá afectada por el cambio climático. El objetivo de este artículo es revisar la importancia de la temperatura en los diferentes procesos a los que se ve sometida el agua a lo largo de la red de distribución y recopilar lo que se conoce hasta el momento sobre modelización de temperatura en redes de abastecimiento. Esta revisión de la literatura resalta la importancia de las condiciones térmicas en las diferentes dinámicas dentro de una red de distribución, detectando la necesidad de mejorar el conocimiento sobre su comportamiento, no solo para caracterizar la calidad del agua suministrada en la actualidad, sino también para evaluar las posibles complicaciones que pueden surgir en futuros escenarios de cambio climático.

A crescente demanda de água para garantir seus múltiplos usos tem gerado escassez dos recursos hídricos e conflitos entre usuários em diversas bacias hidrográficas, sendo necessário otimizar o uso da água para garantir a sustentabilidade das gerações futuras. O objetivo deste trabalho foi analisar a adequação entre a oferta dos recursos hídricos superficiais (Q7,1o e Qm) e as demandas de complementação hídrica para fins de irrigação na agricultura, para a bacia do Entre Ribeiros. Através do balanço hídrico determinou-se os períodos de excesso e déficit hídrico. Para os períodos de déficit hídrico foram determinadas as vazões unitárias requeridas pela irrigação, as quais foram relacionadas com as disponibilidades hídricas superficiais. A disponibilidade hídrica foi caracterizada pela vazão mínima de sete dias de duração e período de retorno de dez anos (Q7,1o), quantificada em base anual e mensal atraves do estudo de regionalização de vazões para Minas Gerais (MG). A metodologia proposta foi aplicada a bacia do ribeirão Entre Ribeiros, localizada na região noroeste de MG, que já apresenta um quadro de escassez e conflitos pelo uso da água. A partir da análise dos resultados, conclui-se que a consideração da disponibilidade hídrica estimada em base anual não garante o suprimento das demandas de complementação hídrica para a área atualmente irrigada na bacia e para nenhuma data de semeadura proposta. Entretanto, quando considerada a disponibilidade hídrica estimada em base mensal, esta garante o suprimento da área atualmente irrigada para a data de semeadura atualmente praticada na bacia. | The increasing demand for water to ensure the multiple uses has generated scarcity of water resources and conflicts between users in many river basins, so, is necessary to optimize the use of water to ensure the sustainability future generations. The aim this study was to analyze adequacy between supply of surface water resources (Q7,1o e Qm) and the demands of water to supplement irrigation purposes in agriculture, for the basin Entre Ribeiros. The water balance determined the periods of excess and water deficit. For periods of water deficit were determined unitary streamflow required for irrigation, which were related to surface water availability. The water availability was characterized by the minimum stream flow of seven days and 10 years of return period (Q7,1o), and their quantification was achieved on an annual and monthly basis through the study of regionalization of streamflow for Minas Gerais. The proposed methodology was applied in the Entre Ribeiros creek basins, located in the northwestern MG region, which already presents a framework of scarcity and conflicts over water use. From the analysis of the results, it is concluded that the consideration of the estimated annual basis, water availability does not ensure the supply of water demands of completion for the currently irrigated area in the basin, nor for any proposed date of sowing. However, when considering the estimated water availability on a monthly basis, this ensures the supply of currently irrigated area for sowing date currently practiced in the basin. | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior