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...

Chemical plant designs with heat or material recycle are becoming more common due to economic and environmental reasons. Underperforming control loops in chemical plants may in some cases be attributed to the presence of recycle streams. This is because recycle alters the dynamics of neighboring processes. During commissioning work, when control engineers are tuning control loops, they are ofte...

Many industrial processes, particularly in the food industry, produce slurriesor wastewaters containing high concentrations of biodegradable organicmaterials. Before these contaminated wastewaters can be dischargedthe concentration of these pollutants must be reduced. A method which has beenextensively employed to remove biodegradable organic matter is biologicaltreatment. In this process the w...

This paper presents the retrofit of five conventional distillation trains for the separation of quaternary mixtures of hydrocarbons for feed compositions with high or low content of intermediate components. The retrofit implies the incorporation of liquid or vapour recycle streams among the conventional distillation columns. Each recycle stream removes one condenser or one reboiler. The introdu...

Natural gas produced at high pressure (50-70 bar) is the only industrial source of helium (He). A membrane separation process may offer a more efficient production system with smaller footprint and lower operational cost than conventional cryogenic system. Inorganic membranes with high mechanical strength are known to exhibit good stability at high pressure. In this work, two inorganic membrane...

Many industrial processes, particularly in the food industry, produce slurries or wastewaters containing high concentrations of biodegradable organic materials. Before these contaminated wastewaters can be discharged the concentration of the biodegradable organic pollutant must be reduced. One way to do this is to pass the wastewater through a bioreactor containing biomass which grows through c...

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 du...

For the separation of azeotropic mixtures with distillation usually a number of conceptual design alternatives are generated. Instead of evaluating the economic viability of the different alternatives by repetitive simulation studies, a combination of shortcut calculations and rigorous MINLP optimization is proposed. In this two step process the shortcut calculations are used to screen and rank...

Nearly 100 tests were performed with prototypical melters and off-gas system components to investigate the extents to which technetium is incorporated into the glass melt, partitioned to the off-gas stream, and captured by the off-gas treatment system components during waste vitrification. The tests employed several simulants, spiked with 99mTc and Re (a potential surrogate), of the low activit...

Recently, on the assumption that the presence of the recycle stream in thermally coupled distillation schemes (TCDS) might origin a difficult operation, some alternate arrangements that might provide better operational properties have been proposed. In this work, on the framework of singular value analysis, control properties of two alternate schemes were assessed and compared with their corres...