A bioreactor which and be used with substrates which are difficult to attain sufficient dispersion is made up of a reaction vessel 1 having a reaction chamber 2 surrounded by a water jacket 3 for maintaining a predetermined constant temperature. The reaction chamber 2 is provided in the vicinity of the inner wall surface 2a of the reaction vessel 2 with a plurality of upright screws 6 and 7 in an adjoining relationship to each other, each screw having a screw thread or a helical fin 6b, 7b of reverse turning sense with each other so that the reactor vessel contents are subjected to a convectional flow induced by the rotation of the screws in the reverse sense to each other by a gearing 14, 15. The substrate therein is subjected to a uniform agitation and to a milling and sieving actions in the portion 13 where the fins of the screws face each other, before the reaction product is removed by a screw conveyer 25.
Horigane, A., Matsukura, U., & Kamio, M. (1997). Bioreactor. Biotechnology Advances, 15(3–4), 705–706. https://doi.org/10.1016/S0734-9750(97)87664-1