19 resultados para Fluido de corte
Resumo:
This study was conducted to evaluate the consumption and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), total carbohydrates (TC), non-fiber carbohydrates (NFC) and neutral detergent fiber (NDF) in sheep fed hay moringa (Moringa oleifera Lam) obtained with four cutting ages (28, 35, 42 and 49 days). We used 20 females Morada Nova breed, with 20kg of live weight, distributed in a completely randomized design and maintained in metabolism cages. There was a negative linear effect of age of cutting on DM intake, with an estimated maximum consumption of 0.67 kg / day for the hay produced at 28 days of cutting. It was also observed linear behavior, with an estimated maximum consumption 172g/dia, 0.36 kg / day; 18g/dia, at 35, 42 and 49 days old, for CP, OM and EE, respectively. For NDF, quadratic effect was found with advancing maturity of the plant. The apparent digestibility of DM, CP, OM and TC linearly decreased with advancing age of cutting hay Moringa oleifera. It was concluded that the hay Moringa oleifera showed better nutritional value after 28 days of cutting
Resumo:
The objectives of this research were characterizing the dairy goat production systems and model it using linear program. On the first step of this research, the model was developed using data from farms that was affiliated in the ACCOMIG/Caprileite, used a similar dairy goat production systems and have a partnership program with Universidade Federal de Minas Gerais . The data of research were from a structured questionnaire applied with farmers and monitoring of production systems during a guided visit on their farms. The results permitted identify that all farms were classified as a small and have a intensive production system. The average herd size had 63.75 dairy goats on lactation; it permits a production of 153, 38 kg of goat milk per day. It was observed that existing more than one channel of commercialization for the goat milk and their derivative products. The data obtained, on the first step of this research, was used to develop a linear program model. It was evaluated in two goat production systems, called P1 and P2. The results showed that the P1 system, with an annual birth and lactation during approximately 300 days was the best alternative for business. These results were compared with a mixed (beef and dairy) goat system in the semiarid region, which indicated merged with both systems. Therefore, to achieve profits and sustainability of the system, in all simulations it was necessary a minimum limit of funding of U.S. $ 10,000.00; this value permit earning of U.S. $ 792.00 per month and pay the investment within 5 years
Resumo:
Cutting fluids are lubricants used in metal-mechanical industries. Their complex composition varies according to the type of operation carried out, also depending on the metals under treatment or investigation. Due to the high amount of mineral oil produced in Northeastern Brazil, we have detected the need to better use this class of material. In this work, two novel formulations have been tested, both based on naphthenic mineral oil and additives, such as: an emulsifying agent (A), an anticorrosion agent (B), a biocide (C) and an antifoam agent (D). Each formulation was prepared by mixing the additives in the mineral oil at a 700-rpm stirring velocity for 10 min, at 25°C, employing a 24 factorial planning. The formulations were characterized by means of density, total acid number (TAN), viscosity, flash point and anticorrosion activity. In a subsequent study, oil-in-water emulsions were prepared from these novel formulations. The emulsions were analyzed in terms of stability, corrosion degree, percentage of foam formation, conductivity, accelerated stability and particle size. The samples were appropriately labeled, and, in special, two of them were selected for featuring emulsion properties which were closer to those of the standards chosen as references (commercial cutting oils). Investigations were undertaken on the ability of NaCl and CaCl2 to destabilize the emulsions, at concentrations of 2%, 5% and 10%, at an 800-rpm stirring velocity for 5 min and temperatures of 25º, 40º, 50º and 60ºC. The recovered oils were chemically altered by reincorporating the same additives used in the original formulations, followed by preparation of emulsions with the same concentrations as those of the initial ones. The purpose was to assess the possibility of reusing the recovered oil. The effluents generated during the emulsion destabilization step were characterized via turbidity index, contents of oil and grease, pH, and contents of anions and cations, observing compliance with the parameters established by the current environmental legislation (Brazil s CONAMA 357/05 resolution). It could be concluded that the formulations presented excellent physicochemical properties as compared to commercial cutting fluids, showing that the quality of the newly-prepared fluids is superior to that of the formulations available in the market, enabling technically and environmentally-safe applications
Resumo:
The construction of wells is one of the most important activities of the oil industry. The drilling process is the set of activities and operations to design, program and perform the opening thereof. During this process, the cuttings are removed by the drilling fluid, or mud, and carted to the surface. This fluid is injected into the drill string and returns to the surface through the annular space between the well walls and the drill string. After the descent of the column casing, the annular space between the casing string and the walls of the borehole is filled with cement so as to secure the spine and prevent any migration of fluids between the various permeable zones traversed by the well behind of the coating. To ensure the good quality of the cementation scrubbers are used mattresses which are pumped ahead of the cement slurry so as to avoid contamination of the drilling fluid paste, or vice versa, and assist in the removal of plaster, formed by drilling fluid of the borehole walls, thus enabling a better cement bond to the well. Within this context, this work aims to evaluate the efficiency of mattresses scrubbers, the basis of ionic and nonionic surfactants, on the removal of nonaqueous drilling fluid, based on n-paraffin in oil wells, and the compatibility between the Mattress relations washer / drilling fluid bed scrubber / cement paste mattress washer / cement slurry / drilling fluid and the drilling fluid / cement slurry using laboratory tests rheology, thickening time and compressive strength. Also technique was performed X-ray diffraction (XRD) for a more detailed analysis of these mixtures with hydrated cement paste. In compatibility tests the conditions of temperature and pressure used in the same laboratory procedure simulating the conditions of oil wells, the well is considered the depth of 800 m. The results showed that the compositions of the mattress washer nonionic, KMS obtained a 100% efficient in removing the non-aqueous drilling fluid, and the best formulation showed good results with respect to compliance testing