Vortex Cyclone Reactor

The advantage of the vortex/cyclone reactor, as with other reactors based on solid-solid contact, is that the reaction takes place primarily at the surface of the particles, allowing large particles to be used as long as they are light enough to be carried by the incoming gas. As a consequence, the overall heat transfer rate is primarily 

As with any other reactor that is based on heating biomass by contacting it with a hot surface, the vortex rector pyrolysis is surface area-controlled. That means the scale-up of these systems is very difficult, and they are t3 pically only used for small scales. 

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Ablative reactors are those in which heat transfer takes place primarily by solid-solid contact. In these reactors, biomass particles or entire wood rods are heated up by direct contact with a hot metallic surface. The solid-solid contact is an advantage from the perspective of increasing heat transfer rates. The main drawback with these reactors, however, is that the process is limited by the surface area of contact, which makes the scale-up very difficult. Ablative reactors should only be considered for small-scale applications. The main ablative reactors are the vortex (or cyclone) reactor and the cone reactor. 

Figure 1 is a sketch of the cyclone reactor. The liquid is fed tangentially into it (A). A gas mixture of SO3 and N2 is introduced into the reactor via a porous section of the cylindrical wall. The liquid phase is the continuous phase in the reactor, except near the cyclone-axis. Here, a gaseous core is found, due to a strong centripetal field, generated by the rotating liquid. This field causes gas bubbles to spiral from the wall to the cyclone-axis. Gas leaves the reactor via the upper outlet which is known as the vortex. Liquid leaves the reactor via the bottom outlet which... 

Figure 1. Cyclone reactor. Unit of length 10 m. ( A) liquid inlet (4 10 m), (B) gas outlet (vortex) (3 10 m),...

The product stream contains gases and soflds. The soflds are removed by using either cyclones, filters, or both in combination. Cyclones are devices used to separate soflds from fluids using vortex flow. The product gas stream must be cooled before being sent to the collection and refining system. The ALMA process uses cyclones as a primary separation technique with filters employed as a final separation step after the off-gas has been cooled and before it is sent to the collection and refining system (148). As in the fixed-bed process, the reactor off-gas must be incinerated to destroy unreacted butane and by-products before being vented to the atmosphere. 

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