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Kevin Bacon
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This is a homework problem that was posted in another forum, so there is no template
I have this problem for my reactor design course and I need some help wrapping my head around it.
We have to design a plug flow reactor (PFR), which can be modeled as five equal volume CSTR's in series. The PFR has an inlet volumetric flow rate of ##q_{in}## which contains species ##A_i, i = 1...n## having concentration ##C_{Ai,in}## (also the whole PFR is operated at a constant temperature ##T_{ref}##).
The PFR is initially filled with solution containing species at concentration ##C_{Ai,0}##. The density of the inlet stream is constant at ##\rho##. There are ##m## reactions taking place within the PFR, each defined by the stoichemetric coefficients ##v_{i,j}## where ##i = 1...n, j = 1...m##.
Our goal is to design the smallest possible PFR to achieve steady state conversion of ##X_{A1} = 0.75##.
We are given a matrix of the stoichometric coefficients:
<br /> v = <br /> \begin{bmatrix}<br /> -a & -b & 0 & d\\<br /> -a & 0 & 0 & d\\<br /> a & 0 & -c & -d\\<br /> 0 & b & c & 0<br /> \end{bmatrix}<br />Basic rate laws:
<br /> r_{A1,1} = -kC_{A1}C_{A2}^2\\<br /> r_{A5,2} = kC_{A1}\\<br /> r_{A4,3} = -kC_{A4}^2\\<br /> r_{A3,4} = -kC_{A3}^2C_{A4}^2<br />
All k = 1, the inlet volumetric flow rate is given and a vector of five values for ##C_{Ai,in}## and ##C_{Ai,0}## are given. My approach so far is to create the net generation term being:
r = [-k*(c(1)*c(2)^2+c(1)^2+c(3)^2*c(4)^2-0.5*c(4)^2);
k*(c(1)-c(1)*c(2)^2);
k*(c(1)-c(4)^2);
k*(c(1)*c(2)^2-c(1)^2+c(3)^2*c(4)^2-0.5*c(4)^2)]
But do I take the CSTR approach or the PFR approach? A general idea would be very helpful. Thank you!
We have to design a plug flow reactor (PFR), which can be modeled as five equal volume CSTR's in series. The PFR has an inlet volumetric flow rate of ##q_{in}## which contains species ##A_i, i = 1...n## having concentration ##C_{Ai,in}## (also the whole PFR is operated at a constant temperature ##T_{ref}##).
The PFR is initially filled with solution containing species at concentration ##C_{Ai,0}##. The density of the inlet stream is constant at ##\rho##. There are ##m## reactions taking place within the PFR, each defined by the stoichemetric coefficients ##v_{i,j}## where ##i = 1...n, j = 1...m##.
Our goal is to design the smallest possible PFR to achieve steady state conversion of ##X_{A1} = 0.75##.
We are given a matrix of the stoichometric coefficients:
<br /> v = <br /> \begin{bmatrix}<br /> -a & -b & 0 & d\\<br /> -a & 0 & 0 & d\\<br /> a & 0 & -c & -d\\<br /> 0 & b & c & 0<br /> \end{bmatrix}<br />Basic rate laws:
<br /> r_{A1,1} = -kC_{A1}C_{A2}^2\\<br /> r_{A5,2} = kC_{A1}\\<br /> r_{A4,3} = -kC_{A4}^2\\<br /> r_{A3,4} = -kC_{A3}^2C_{A4}^2<br />
All k = 1, the inlet volumetric flow rate is given and a vector of five values for ##C_{Ai,in}## and ##C_{Ai,0}## are given. My approach so far is to create the net generation term being:
r = [-k*(c(1)*c(2)^2+c(1)^2+c(3)^2*c(4)^2-0.5*c(4)^2);
k*(c(1)-c(1)*c(2)^2);
k*(c(1)-c(4)^2);
k*(c(1)*c(2)^2-c(1)^2+c(3)^2*c(4)^2-0.5*c(4)^2)]
But do I take the CSTR approach or the PFR approach? A general idea would be very helpful. Thank you!