n this paper, a mathematical model has been derived to predict the granulation time of anaerobic sludge in UASB reactors. In the proposed model, some physical, chemical and biological parameters affecting the granulation phenomena have been considered. To validate the model, 12 pilot-scale experiments in 4 UASB reactors are carried out and the results are discussed here. The reactors are starte...

Although the operation under unsteady state is generally avoided and continuous operation is preferred in the chemical industry, this mode of operation can often lead to a better performance. Because of this, forced unsteady state reactors are object of increasing interest. In particular, the systems based on the periodic reversal of the feed flow direction, called reverse flow reactors (RFR), ...

submerged breakwaters are one of the shore protective structures. any discontinuity in these breakwaters causes changes on current parameters including speed and water surface profile. in this paper, discontinuous submerged breakwaters were modelled to investigate the changes in the wave and flow pattern.to investigate the phenomenon, three models including a shore with constant slope, a shore ...

In this paper wave transformation in a submerged sloped breakwater and its hydraulic performance was simulated by developing a numerical model in Fortran. The code was established by combining porous flow and a two-phase model using VOF method. Modified Navier-Stokes and k-ε equations implemented to the model to simulate the flow in porous media. Cut cell method was modified to simulate...

Submerged membrane bioreactors (MBRs) have been gaining in popularity in various types of wastewater treatment. One drawback of submerged MBRs is the difficulty in removing nitrogen because intensive aeration is usually carried out in the tank and the MBRs must therefore be operated under aerobic condition. In this paper, feasibility of a baffled MBR (BMBR), treating municipal wastewater partic...

Submerged aquatic vegetation can dramatically alter the drag, turbulence and diffusivity characteristics of flow in aquatic systems. As a result, the diffusion and advection of contaminants and particulates are greatly influenced. However, modeling efforts generally treat submerged vegetation merely as a source of drag. This study explores the idea that flow through submerged aquatic vegetation...

Laboratory scaled flow-through processes have seen an explosive development over the past decade and have become an enabling technology for improving synthetic efficiency through automation and process optimization. Practically, flow devices are a crucial link between bench chemists and process engineers. The present review focuses on two unique aspects of modern flow chemistry where substantia...

Scour around hydraulic structures is an inevitable phenomenon . Recognition of this phenomenon and dealing with it is an issue considering which will ensure the project success . Local scour at piers has been reported as the most important factor in the destruction of the bridges . The use of submerged and non-submerged piles is one of the scour control methods . Submerged piles have been rarel...

The constraints and advantages in cellulolytic enzymes production by fungal biofilms for a consolidated bioconversion process were investigated during this study. The biofilm cultivations were carried out in reactors designed for consolidated bioprocessing Multispecies Biofilm Membrane reactors, (MBM) where an aerobic fungal biofilm produces the lignocellulolytic enzymes while a fermenting micr...