Experimental and Numerical Investigation of a Reactive Absorption Column for Chlorine Gas Mitigation

Abstract

Chlorine gas is extensively used in a variety of chemical processes as an end product or reactant, for instance, in the conversion of phthalocyanine dye. Reactive absorption (RA) columns can be applied for the treatment of the waste gas streams at the outlet of the reaction equipment, in order to satisfy the environmental regulations, and these should be prepared for potential accidents. The objective of this study was to evaluate an industrial-scale RA column for the treatment of chlorine gas stream in a phthalocyanine plant in the case of an accident. A coupled experimental and numerical study was performed. A factorial design was applied for the definition of a set of experimental conditions to be evaluated in a pilot-scale plant operated in the laboratory. The data collected were treated by means of the response surface methodology, and coupled numerical schemes allowed the determination of the mass transfer coefficient and the reaction rate constant. Finally, numerical studies were carried out to assess the industrial-scale column behavior. It was found that the industrial absorption column was able to treat a stream of chlorine at a flow rate of 900 kg/h with an efficiency of approximately 79%.

Keywords:

• Chlorine gas
• Numerical simulation
• Parameter regression
• Pilot and industrial scale
• Reactive absorption column