19-08-2014, 10:38 AM
Rotational speed and disk diameter control the values of residence time and level of mixing. The centrifugal force creates highly sheared thin film, which generate high heat transfer between the liquid and disc and high mass transfer between the liquid and air (or gas). The waves also produce intense local mixing and form an almost pure plug flow. Due to such advantages, reactions with fast intrinsic kinetics, exothermic reactions and heat sensitive materials can be handled efficiently.
A Spinning Disc Reactor (SDR) is a novel reactor, consisting of a horizontal disc rotating at high speed.
Rotational speed and disk diameter control the values of residence time and level of mixing. The centrifugal force creates highly sheared thin film, which generate high heat transfer between the liquid and disc and high mass transfer between the liquid and air (or gas). The waves also produce intense local mixing and form an almost pure plug flow. Due to such advantages, reactions with fast intrinsic kinetics, exothermic reactions and heat sensitive materials can be handled efficiently.
In the present work, synthesis of magnetite (Fe3O4) particles in both spinning disk reactor (SDR) and conventional stirred tank reactor is carried out. In spinning disk reactor, reactants (ferric chloride, ferrous chloride and sodium hydroxide) dissolved in water are fed according to stoichiometry of the reaction to the centre of the rotating disc. The reaction takes place in the thin film along the radius of the disk.
The effects of rotational speed, diameter of the disk, surface characteristics of the disk and flow rate of reactants on conversion of ferric chloride are found out. Using the obtained results, operational window for a given disk is suggested. Better particle size distribution compared to stirred tank reactor is obtained in SDR.