Berty-type internal recycle reactors offer great opportunities for screening catalysts and reproducing catalytic reacting conditions in multiple processes, thus approaching industrial reactions while amplifying kinetic information. However, the rational design of these requires a deeper understanding their governing hydrodynamics equations so that they can be better utilized batch or continuous...

In this paper, first we identify the destruction ways of concrete constructions and the benefits of waste management and the plans to recycle the concrete debris were investigated and it was concluded that the existence of plans to recycle the concrete debris could lead to big economic save ups and by recycling these debris we can create affordable ways for concrete making centers. By the way, ...

A mathematical model for the prediction of internal recirculation of complex impinging stream reactors has been presented. The model constitutes a repetition of a series of ideal plug flow reactors and CSTR reactors with recirculation. The simplicity of the repeating motif allows for the derivation of an algebraic relation of the whole system using the Laplace transform. An impinging stream...

Problem statement: The activated sludge system is a complex dynamic process and must account for a large number of reactions between large numbers of components. There is necessity for simulation models which describe the dynamic behavior of the activated sludge process. The application of the models in most treatment plants is limited due to lack of appropriate data acquisition and parameters ...

Factorial experiments were conducted to investigate the effect of chlorination filtrate recycle on toxicity and organically bound chlorine in the first two stages of softwood kraftpulp bleaching. The effects of the mode of chemical addition, the substitution of chlorine dioxide, and the kappa factor were also studied. A continuous laboratory-scale (6.0 o.d.g/min) chlorination apparatus was desi...

the purpose of this study was to look for carbon materials for composting with rabbit manure. rabbit manure was composted with rice straw and mushroom residues. during the composting process, different related parameters were evaluated. results showed that the rabbit manure could be normally co-composted with rice straw or with mushroom residues. the gi value showed that both composts could hel...

in this paper a new process is presented for improving efficiency of cyclone de-dusting systems. the cyclone is coupled with a specially designed cylindrical chamber which includes a rotating tube inside it with air impinging nuzzles, drilled on the peripheral surface of the tube. the nuzzles help in pushing and throwing the particles to the outer radius distances during downward flow of dust i...

geophysical fluids such as atmosphere and ocean often have stable density stratification; hence internal gravity waves are generated and propagated through them which are important in momentum and energy transfer in these media. these waves are also believed to generate layered structures in such media. recently there have been numerous theoretical, experimental and numerical studies on the way...