Describes non-ideal flow in reactors.
RTD E(t) describes how long fluid elements stay in a vessel; characterised by tracer experiments (pulse, step). Mean residence time τ=V/v and variance reveal mixing, dead zones and bypassing. Models: tanks in series, dispersion model.
A tracer test on a reactor shows bypassing as an early peak.
Residence time distribution describes how real reactors deviate from ideal mixing, which explains lower conversion or unexpected products.
Describes non-ideal flow in reactors.
Residence time distribution describes how real reactors deviate from ideal mixing, which explains lower conversion or unexpected products.
Adding a small pulse of an inert tracer at the inlet and measuring its concentration at the outlet over time to find the residence time distribution.
A reactor with a wide spread of residence times lets some material leave too early, which lowers the average conversion.
Typical applications include diagnosing poor performance of a reactor with dead zones, using a tracer test to find the mixing behaviour of a vessel and estimating the conversion in a reactor with known mixing from its tracer curve.
Study "Heterogeneous catalysis" first (topic 86 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
Cumulative F(t). Peclet number. Segregation vs maximum mixedness.
A tracer test on a reactor shows bypassing as an early peak.
The next topic is "Mass transfer", which builds directly on this one.
It is classed as Advanced in Materials & Chemical (topic 87 of 100). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Materials & Chemical.
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