Modern trends in the mathematical simulation of pressure-driven membrane processes

The presented article is an attempt to evaluate the progress in the development of the mathematical simulation of the pressure-driven membrane processes. It was considered more than 170 articles devoted to the simulation of reverse osmosis, nanofiltration, ultrafiltration, and microfiltration and the others published between 2000 and 2010 years. Besides the conventional approaches, which include the irreversible thermodynamics, diffusion and pore flow (and models which consider the membrane surface charge for nanofiltration process), the application of the methods the computational fluid dynamics, artificial neural networks, optimization, and economic analysis have been considered. The main trends in this field have been pointed out, and the areas of using approaches under consideration have been determined. The technological problems which have been solved using the mentioned approaches have also been considered. Although the question of the concentration polarization has not been considered separately, it was defined that, in many cases, the sufficiently accurate model cannot be designed without considering this phenomenon. The findings allow evaluating more thoroughly the development of the simulation of pressure-driven membrane processes. Moreover, the review allows choosing the strategy of the simulation of the considered processes

The correction of the dimensionless equation for the mass transfer coefficient estimation during the membrane modules regeneration

The cleaning or regeneration of fouled membrane modules is an essential procedure in the membrane equipment operation. Despite the development of some successful cleaning techniques, the predictions of the membrane separation process operation parameters after regeneration is still an unsolved problem. In our previous works, the attempt to develop the methodology of estimating the membrane productivity after the regeneration of the fouled spiral wound membrane modules by cleaning the subatmospheric pressure has been made. However, this methodology requires some improvement, including the correction of the dimensionless equation to calculate the mass transfer coefficient. In this work, a set of additional experiments was carried out, and the corrections of the mass transfer correlation were done using both new and previously obtained experimental data. As a result, the improved dimensionless equation was contained as Sh = 0.00045Re0.8Sc0.33(de/l). This equation is valid in the range of Reynolds number variation of 0.4–60.0 for the case of the regeneration of spiral wound modules and can be used for the prediction of the permeate flux after the regeneration procedure