Enrico Remigi WEST Product Owner

Hi,
actually the SBR model has got 3 'flow' outputs (and 1 'data' output): you can use the 'F1' key when the block is selected on the layout to access the model description (see image).
It's essentially up to you to make sure that the by-pass (terminal 'out_3') is nil at all times.
Then you will have an effluent flow ('out_1') and a sludge withdrawal ('out_4'): whether you want / need to graphically connect these terminals to other terminals, is entirely up to you, not necessary.

I don't understand why you would use a 2-combiner though: to connect what?

[quote author=Ruben link=topic=20133.msg26068#msg26068 date=1496508278]
1. As you recommend me I've tried and achieved to calculate the SRT and HRT variable states by using the Process Calculator Block but it’s not possible for me to calculate the F/M ratio (picture in attached file). What is the reason and how should I proceed? I’ve seen in the description of that block that it should be possible to calculate the F/M ratio. Could it be possible to calculate any other state variable with that block? How can I introduce its formula?
[/quote]
The snapshot shows the connection between the calculator block (out) and a data treatment block (in): this has nothing to do with the calculation of the F/M ratio which is an algebraic state variable computed within the calculator block and which needs the relevant input variables.

[quote author=Ruben link=topic=20133.msg26068#msg26068 date=1496508278]
2. I've managed to solve my problems wits the input and output general blocks but I still have problems to introduce an Iron or Alum Dosing block to the diagram. As you told me, my Dosing block doesn't display any valid output terminal but I don't know why. Should I create it previously? How and Where? I'm using the ASM2dM instance.
[/quote]
You're right: those chemical dosing models are not enabled for ASM2dM. It's a mistake: we're going to fix this as soon as possible.

[quote author=Ruben link=topic=20133.msg26068#msg26068 date=1496508278]
3. If it's only possible to use the Anaerobic Digestion Blocks when we are using the ASM1 instance, is there any option to evaluate the biological P removal and the anaerobic digester performance in the same simulation?
[/quote]
Not with the standard library.
In order to achieve that, you need to convert the ASM2 state vector into an ASM1 state vector - which then can be connected to the anaerobic digester block.

[quote author=Ruben link=topic=20133.msg26068#msg26068 date=1496508278]
4. Is there any difference betwen the use of a multiprobe sensor or an especific one to read (and the use) a variable?
[/quote]
No: the multiprobe sensor measures all quantities that are measured by the individual sensors.

[quote author=Luís Roque Silva Lopes link=topic=20174.msg26064#msg26064 date=1496404335]
I'm using the standard parameters of the secondary decanters that exist in the WEST, however my affluent has the high particulate fraction (75% - 79% of XCOD), and I find very low TSS values in the treated effluent
[/quote]
I guess it's fair to say this is a typical situation in which you need to [b]calibrate the model[/b] on your experimental data

[quote author=Luís Roque Silva Lopes link=topic=20174.msg26064#msg26064 date=1496404335]
Is there any paper / article that I can find information about sedimentation conditions due to the fractionation of the effluent, or other similar situations?
[/quote]
I am sure there's plenty of literature on the subject.
I am not an expert in this area - maybe other users can provide their input?
Otherwise, I suggest you to run a search on one of the scientific engines available

[quote author=Ruben link=topic=20133.msg26060#msg26060 date=1496387250]
1. Does WEST calculate by itself basic system operational paràmeters values like SRT or OLR? What can I do to see them? So far I've only achieved it by creating them as new algebraic variables and introducing their formula.
[/quote]
No, not 'automatically'.
Yes, one way is to create so-called [b]Calculator Variables[/b], which is what you did. This approach has advantages (it's very quick) and disadvantages (not reusable outside of the project).
Another way (as of rel.2017) is to create a [b]Top-level State Variable[/b] - with the advantage, over the Calculator Variable, that you can write complex expressions.

For SRT though, you should rather use the 'OperationalParameters' model associated with the [b]Process Calculator block[/b] - and provide the necessary quantities to it by connecting the relevant terminals in your layout.

[quote author=Ruben link=topic=20133.msg26060#msg26060 date=1496387250]
2. I have some problems to connect some input and output blocks to the flow diagram (please find the attached file):
  error 1) I've been trying to define a temperature cycle through an input block connected to the ASU unit but when I execute the simulation it's not reproduced.
  error 2) It’s not possible to connect an output bock for a variable to be shown (OD for instance) from the ASU block.
  error 3) It’s not possible to connect an Iron dosing or Alum dosing block to a flow line (same error message as in error 2).
How should I proceed to do that properly?
[/quote]
[1] Are you sure you're executing the Dynamic Simulation and not the Steady-State Simulation - which will use the computed average temperature, which may very well be 20 degC?
Or: are you sure the Input block is connected to the Temp variable of the tank - which is the one you're plotting?
[2] The reason why it does not allow you to finalise the connection is because you haven't defined a top-level interface variable of type 'Output'.
Anyway, why do you need an explicit Output block? this is not necessary to e.g. plot a variable, or send it to a file output ...
[3] It should not be the case. Why does your Iron Dosing block not display a valid output terminal? which Instance are you using?


[quote author=Ruben link=topic=20133.msg26060#msg26060 date=1496387250]
3) Is it possible to use an anaerobic digester in all the models (instances)? How can I see how WEST does the conversion of ASM1 or ASM2d variables into ADM1 variables?
[/quote]
No, it can only be used in the scope of an ASM1 Instance.
The Models Guide contains a detailed description of every model.

[quote author=Ruben link=topic=20133.msg26060#msg26060 date=1496387250]
4) I haven't seen any specific block for the aerobic digesters. Are we supposed to model it like a norma ASU unit?
[/quote]
Yes, that would be my approach as well.

I would guess 10-15% of the particulate COD, or less

You write BCOD and BOD: I am confused ...
If 0.85 is BOD / COD, I would say it is rather high.

[quote author=Luís Roque Silva Lopes link=topic=20169.msg26050#msg26050 date=1496276209]
A) The COD / BOD ratio you are talking about, the BOD is the total, or the first five days, or the first few days?
[/quote]
I would say BOD5

[quote author=Luís Roque Silva Lopes link=topic=20169.msg26050#msg26050 date=1496276209]
B) I saw a work in which the input fractionation scheme is similar to the standard fractionation scheme of the WEST, however, it had a connection of TSS and X_TSS with a ratio of 1.
[/quote]
When you say "standard fractionation scheme of WEST", I presume you are referring to the ASM1 fractionation model.
X_TSS is a component of ASM2(dModTemp), which is equally "standard".

Bottom line is: if you have BOD measurements as well, you need to ensure that the '[b]calculated BOD[/b]' is as close as possible to your measurements; or in fact, the ratio close to 1.

I mean Biological or Biochemical Oxygen Demand.
Yes, in ASM1, BOD is the combination of S_S, X_S and part of X_BH, X_BA.

Not at all !
Those values are completely unrealistic.
I cannot say what may go wrong because I don't know what your process looks like or the data you are using, I can only speculate.
If you are talking about alternatives for the influent fractionation (the COD to TSS conversion), I assume you are attempting to calibrate a (complex or not) process model only based on influent data. This is a 'dangerous' approach which is bound to result in completely awkward estimates of kinetics parameters - the relation between those and the influent specs is kind on loose ...
You should first calibrate your influent model to make sure that you feed your process with a [b]'correct' influent[/b]; then you should probably look at the steady-state behaviour of your system (sludge age, MLSS, etc.); and only then, if necessary and if you have data to support that, calibrate the kinetic model.
I don't know which data you have for your influent (e.g. COD, TSS, TN, .. ? BOD, TSS, .. ? rbCOD, ..? several combinations are possible), but you need to perform, at least (!) some continuity checks.
For instance: if you have COD and TSS and derive soluble and particulate COD based on F_TSS_COD (the standard fractionation in WEST), you need to make sure that the [b]calculated BOD[/b] (combination of COD components that contribute to BOD) is reasonable, i.e. 2-2.5 or so COD / BOD; or even better, if you have a BOD measurement as well, close enough to your measurement.

Correct.
Temp_Ref is the reference temperature at which the temperature-dependent kinetic [b]parameters[/b] (e.g. growth rates) are given.
For instance, mu_H (parameter) is given at 20 degC (reference temperature) and the actual mu_H_Temp ([b]variable[/b]) is computed using the Arrhenius function.

I don't fully understand what you are trying to achieve.
How do you control the input power?
And how do you set up the Parameter Estimation experiment? What are your degrees of freedom, i.e. model parameters that will be varied during the PE? what's the objective function?

You can fix the DO by either using the FixVolumeFixOxyASU model; or controlling the aerator (e.g. using a PI controller) and fixing the set-point of the DO.