Higee distillation process

Ramshaw C. Higee distillation—an example of process intensification. Chem Eng 1983 389 13-14. 

Ramshaw, C. (1983). Higee distillation-an example of process intensification. Chemical Engineering, 389, 13-14. 

Ramshaw, C., Higee Distillation— An Exanple of Process Intensification, Chem. Engr., (389), 13 (1983). 

The amount of hazardous chemicals on-site can be reduced by methods other than altering the scale of production. For example, the amount of hazardous material stored on-site can often be significantly reduced, and if not, the hazardous materials can be stored in many small containers in separate facilities rather than in a single container. Therefore, if a container fails, the size and catastrophic potential of the release are much reduced. In addition, the amount of material needed in the production process can be reduced by using specially designed equipment (such as Higee columns, which replace conventional distillation columns). 

A number of approaches can be adopted to reduce energy use in the columns, two major examples of which can involve process intensification. The first of these, improvements to the distillation column population to make the units more efficient rather than wholesale replacement by intensified alternative separation methods, is the most likely route in the short- to medium-term, covered briefly below. In the longer term, alternative plant or separation techniques are needed. Potentially the most important of these is HiGee. 

Three HiGee units were installed by Dow Chemicals in the US for stripping hypochlorous acid, used as the reactive chemical in a process. The rotating packed-bed used for stripping was selected after other alternatives such as a spray distillation tower were rejected for capital cost reasons. The packing selected was a woven wire screen, with the gas flowing counter-current to the liquid. Various packing surface areas were tested, with 2000-3000 m /m area densities, but these exhibited no performance differences so the lower value was used. 

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