Modelagem e simulação do tratamento de água produzida usando um separador ciclônico filtrante.

Abstract

The oil industry, in general, function with elevated produced water volumes, which, present great complexity in its composition, presenting high oil content, which makes it potentially damaging to the environment. The oil/water separation process that utilizes hydro-cyclones has been being an alternative to attend the requirements of the environmental agencies. However, such equipment is not efficient for the treatment of very diluted oily waters. In this sense, the present work proposes the use of an equipment, denominated as a filtrating cyclone separator, which has functioning principles similar to a hydro-cyclone, which has a conical wall formed by a ceramic membrane, and two outlets (concentrate and dilute) at the bottom of the equipment. For the study of the oi/water flow in the filtrating cyclone separator, the computational package ANSYS CFX® 15 was used, adopting an eulerian-eulerian approach for the solution of the mass and momentum conservation differential equations. The constitutive equations pertinent to the closure of the involved phases were adopted. The SST turbulence model was adopted. The Grid Convergence Index was used to analyze the independence of the numerical results from the utilized mesh. The dynamics of the flow, as well as the influence of the variation of the inlet velocity, the mixture’s oil volume fraction, the influence of the concentration polarization layer and the membrane rejection coefficient in the separation process were analyzed. The numerical results confirm the three dimensional behavior of the multi-phase flow at the interior of the filtrating cyclone separator. The formation of a concentration polarization layer was shown to be influenced by the hydrodynamic behavior of the flow, mixture properties and the porous media. The high levels of turbulence at the interior of the filtrating cyclone separator substantially favor the mass transport and the dispersion of the concentration boundary layer. These results have shown that the filtrating cyclone separator has good potential for oil/water separation.