The Batch Process Used in China

All reactors have a diameter of 1.5 m and a height of 8 m. Rather oddly, they are made of mild steel and have an enormous wall thickness of 50 mm to sustain the corrosion. There is no lining, but the inside wall gets covered, and somewhat protected, by furfural polymers naturally formed in the process. The raw material usually consists of ground corncobs from which the fines were removed by sifting. The particle size is between 20 and 30 mm, and the initial moisture content of the raw material is in the order of 15 percent. 

Instead of using a secondary steam generator, the Chinese process passes the reactor vapor directly through the reboiler of the azeotropic distillation column, and instead of using a recovery column for low boilers, most of the latter are flashed into the atmosphere before distillation starts. 

As in the case of the batch process of QUAKER OATS, the furfural yield in the distillate is in the order of 50 percent. 

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