I need to calculate a linear velocity (cm/ml) parameter for fixed bed column studies. Please let me know the formula and how to carry out the calculations.
Linear velocity for fixed beds (m/min) can be calculated in several ways. The simplest way is by dividing the volumetric flow rate (m3/min) by the cross sectional area of the fixed bed (m2). However, bear in mind that this allow you to know an AVERAGE linear velocity.. If your flow rate is varying within the column (as usual), you should require a previous integration step to know the linear velocity at each position.
One of the easiest method to find the linear velocity is given by Daniel Beneroso.
But there are 3 types of fixed bed studies. 1. Fixed head and variable flow method 2. Fixed flow and variable head method 3. constant head and flow method. Generally the third method is adopted for the processes like adsorption. In this case dividing the volumetric flow rate (m3/min) by the cross sectional area of the fixed bed (m2) will give the linear velocity of the fixed bed. But during the experiments, the flow rate of the system reduces, especially in downward flow mode of operation. This is mainly due to the reduction in permeability by the sorption of pollutant. Therefore, during experiments the researchers should take care on the flow rate.
I have a column length of 30 cm and diameter 1.5 cm, flow rate is 100 ml/min. What will be the linear velocity. Is linear velocity and superficial velocity are same.