Whirling bed

The Blowdec depolymerization process from Slovakia converts waste plastics into low-sulphur diesel fuel [35]. The main principle is the processing of waste plastics in a hot whirling bed of hot sand in the BLOWDEC reactor (Figure 15.19). The plastic is heated to 430°C. The process allows for simultaneous cracking of hydrocarbons and inhibition of coke formation. The fluidized sand bed products three types of cracking reactions mechano-activation thermal and catalytic (Si02/aluminosilicates). The process is covered under the US Patent 6,165,349. The process enables the economical conversion of mixed waste plastics into liquid hydrocarbons, mainly low-sulphur (25 ppm) diesel... 

The kinetics of a mixed platinum and base metal oxide catalyst should have complementary features, and would avoid some of the reactor instability problems here. The only stirred tank reactor for a solid-gas reaction is the whirling basket reactor of Carberry, and is not adaptable for automotive use (84) A very shallow pellet bed and a recycle reactor may approach the stirred tank reactor sufficiently to offer some interest. 

Stop the eluent flow when the meniscus of the supernatant liquid has reached the bed surface. Carefully add the sample and avoid whirling up the gel, open the outlet until the liquid has retracted and then start the elution. 

Blowdec A process for converting waste plastics into diesel fuel. The plastic is injected into a bed of hot whirling sand. Developed in Slovakia from 1997. 

During 1970 Operation Euroka was performed in Queensland, Australia [645], This fire was principally of brigelow, a heavy dense hardwood. The slash was arranged by bulldozers into fire beds that had very little fine material hence the peak combustion rates were considerably later and lower than those of the U.S. A. fires. The fire had peak energy release rates of about 120 kW/m2. During Operation Euroka maximum winds were 20 m/s, and after 30 minutes a fire whirl developed. Winds tended to spiral inward from around the fire which covered an area of about 2 ha. 

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