Modelling Pressure Drop to Calculate Conversion of Silicon and Methyl Chloride in a Fluidized bed Reactor


Three experiments were curried out at different reaction temperatures [ 250, 300,330 oC ], for the reaction of silicon with methyl chloride in a fluidized bed reactor, inorder to evaluate a new predicted model that calculate both conversions of reacted solid(silicon) and reacted gas (methyl chloride) as function of pressure drop along the bed.The reacted gas velocity was selected to be above the minimum fluidizationvelocity [velocity selected 2.6 cm/s, minimum fluidization velocity 1.8 cm/s] for the solidparticles (size used 130 μm). A digital pressure drop measuring device was used at threepoints of the reactor (before and after the distributor and finally 50 cm above thedistributor), to determine the pressure drop along the column, also an online GC wasconnected to the outlet reacted gas to analyze the product.A comparison between the conversions of methyl chloride and silicon calculatedfrom pressure drop data and that detected by the online GC, show a proper agreementwith less than 5 % absolute average error.Two equations [16, 18], derived analytically, were equation [8, 18] used tocalculate the conversion of silicon and methyl chloride as function of pressure drop,equation [16] used to calculate the conversion of silicon as function of conversion ofmethyl chloride.