Chemical Engineering & Technology
Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Every month, the Editors select two papers referring to current discussions in the scientific, public and economic communities and in view of the potential for further developments. The papers are freely accessible for one month.
Back Pressure Regulation in Continuous Flow
February 10, 2015
The use of enabling technologies is becoming an increasingly popular tactic in modern synthetic chemistry. This popularity is due to the now well documented benefits of improved heat and mass transfer, reaction control, safety, scalability and potential for automation which are characteristic of continuous chemical processes. The ability to operate under high pressure, and thus access superheated conditions, is one of the key benefits of continuous processing but currently available flow reactor back pressure regulator systems do not tolerate solid particulates and are a common blockage point in any reactor. Benjamin J. Deadman et al. developed a simple alternative method of generating back pressure in flow reactor systems. The device was constructed from commercially available components, was adaptable, and most importantly was found to be effective in the flow processing of thick chemical slurries under high-pressure conditions.
Benjamin J. Deadman, Duncan L. Browne, Ian R. Baxendale, and Steven V. Ley
Back Pressure Regulation of Slurry-Forming Reactions in Continuous Flow
Chem. Eng. Technol. 2015, 38 (2), 259–264.
Annular Photoreactor with Tangential Inlet and Outlet
February 10, 2015
Photochemical treatments based on ultraviolet radiation are promising technologies to remove pollutants from industrial and municipal wastewater or to increase their biodegradability. The performance of UV reactors relies on their fluid dynamics. The reactor geometry and the interaction between the fluid and the UV lamps generate complex structures like recirculation zones, flow separation, and vortex shedding. The fluid flow affects the distribution of chemical species and the radiation intensity throughout the reactor due to species absorption. Ardson dos S. Vianna Jr. et al. presented a combination of macroscopic and microscopic strategies to analyze flow in a U-shaped photoreactor, but with inlet and outlet tubes tangential to its body. It is a modification of the traditional U-shaped geometry intended to force flow in a helical path along the reactor and increase its residence time. The fluid flow was characterized by residence time distribution experiments, which were reproduced by computational fluid dynamics.
José Carlos G. Peres, Uirá de Silvio, Antonio Carlos S. C. Teixeira, Roberto Guardani, and Ardson dos S. Vianna Jr.
Study of an Annular Photoreactor with Tangential Inlet and Outlet: I. Fluid Dynamics
Chem. Eng. Technol. 2015, 38 (2), 311–318.