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The purpose of this paper is to present an experimental study of brick drying. For the drying experiments, industrial brick (clay) was dried in an oven under controlled conditions of air velocity, air temperature and air relative humidity. The continuous drying experiments ended when the mass reached constant weight. In order, to obtain the balanced moisture content, each sample was kept under the same drying air temperature for 48 hours inside the oven. The tests were performed under atmospheric pressure. Results of the drying and heating kinetics and volume variations during the process are shown and analyzed. It was verified that air temperature has big influence in the drying rate during process. It was verified that the largest temperature, moisture content and stress gradients are located in the vertexes of the brick. The drying process happens in the falling drying rate period.

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The importance of heavy oils in the world market for petroleum has increased very quickly in the last years. The reserves of heavy oils in the world are estimated at 3 trillion barrels, while reserves of light oils have reduced progressively in the last decade. The high oil viscosity creates major problems in the production and transportation of the oil. This situation leads to the high pressure and power required for its flow, overloading and damaging the equipment, increasing the cost of production. Due to the need to develop new alternatives that will make the production and transport of heavy oil economically viable, this work has the objective to study, numerically, the behavior of isothermal multiphase flow (heavy oil and water), type "core flow", in pipelines, using the software CFX ® 3D. The pressure drop was determinated to a core-flow in a pipe with 7 in. diameter, 2.7 Pa.s oil viscosity and water at environment temperature. Results of the pressure, velocity and volume fraction distributions of the phases are presented and analyzed. It was verified that the pressure drop was reduced 58 times when compared to that obtained with oil flow alone in the pipe.

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Environmental agencies do not allow effluents, from the petroleum productions, which contain oil concentrations that exceed the amounts permitted by the regulations. In recent time heavy oil operating petroleum industries are generating oil/water mixture by products, which are difficult to separate. Industrially, hydrocyclone is generally used to separate oil from an oil/water mixture. This is due to its high performance of separation, low cost of installation and maintenance. In the present work, therefore, the thermal fluid dynamics of water/ultra-viscous heavy oil separation process in a hydrocyclone has been studied. A steady state mathematical model which simulates the performance of a non-isothermal separation process is presented. The Eulerian-Eulerian approach for the interface of the phases involved (water/ultra-viscous heavy-oil) is used and the two-phase flow is considered as incompressible, viscous and turbulent. For carrying out numerical solutions of the governing equations the CFX11 ® commercial code was used. Results of the behavior of the two-fluid flow inside the hydrocyclone and separation efficiency are presented and analyzed. The role of the average temperature of the fluid, oil droplet diameter and the fluid mixture inlet velocity on the separation efficiency of the hydrocyclone are verified.

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