In this study we designed a cost-effective solar photovoltaic (PV) powered reverse osmosis (RO) desalination plant for Masdar Institute of Science and Technology. The proposed system allowed us to design a RO plant that does not rely on expensive batteries or extra land and drastically decreased the government expenses to subsidize the water production cost to 84% of the current expenses. In additional, the system allowed to reduce the emission of GHG by 1,035 tCO2 annually. The equity payback time was found to be 23.3 years and the benefit-cost ratio to be 0.72. Comparing the results obtained with the conventional values, it can well be said that this system would definitely provide a much needed efficient alternative to the current method of water purification making it more sustainable and economically feasible at the same time.

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With the passage of time for chemical operations involving packed-bed reactors, especially in petroleum refining and petrochemical industries, non-filterable fines such as coke, corrosion products and fine clay in oilsands bitumen deposit on the catalyst particles. The gradual entrapment and deposition of fine particles of range 0.7-20 mm cause the poreplugging phenomenon to occur which consequently blocks the flow passages inside the porous medium. To understand the plugging phenomenon and its effect on hydrodynamic of the reactor, we developed a computational fluid dynamics model which is based on reactor collection efficiency, filtration rate, Brownian motion and interfacial momentum exchange terms to simulate the pressure drop due to deposition of fine particles in real conditions. With the help of this model, we have studied the effect of fines deposition on bed porosity and clogging. This is for the first time that Ansys Fluent has been used to simulate fine-particle deposition in packed-bed conditions. The result was a EulerianEulerian 2-D computational fluid dynamics model which considered all the three phases, i.e. liquid, catalyst and fine particles. The results were validated against the experiments reported in the literature and reached good agreement.

We present a comparative study of the onset and propagation dynamics of the fingering phenomenon in uniform porous media with a radial configuration. With the help of the Finite Element Method (FEM)-based 2D simulations and image processing techniques, we investigate finger morphology, growth rate, interfacial length, finger length and the number of fingers which are affected due to inertial forces and convective acceleration in a two-phase porous media flow. We considered a modified Darcy’s law with inertial force coupled with convective acceleration and investigate their impact on interfacial instability with different velocity-viscosity combinations. Interestingly, the consequences of inertial corrections become significant with changes in viscosity at high Reynolds numbers. Due to the intrinsic bifurcation nature of inertial forces in the radial flow geometry, finger morphology is changed mostly at high viscosity ratios. We find that the effects of inertia and convective acceleration are markedly significant at relatively high Reynolds numbers while the interfacial length and the number of fingers—which are important parameters for Enhanced Oil Recovery (EOR)—are most affected by the neglecting of these forces. Moreover, at high Reynolds numbers, the rate of growth of fingering instabilities and the fractal number tend to deviate from that for Darcy’s law.

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