Enrico Remigi WEST Product Owner

Do you mean a Trickling Filter block (as it's currently implemented, i.e. a biofilm- + suspended-growth conversion models) coupled to a 'solid separation' block (e.g. point-settler) ?
It sounds like a reasonable approach to me, yes.

To avoid confusion with the identifiers ..

If your model is declared as follows:
CLASS ABCModel (* icon = "ABCIcon" *) extends WWTPAtomicModelWithoutVolume WITH

Then the IconName should be [b]ABCIcon[/b] - i.e. the string used for the 'icon' annotation in the above class definition.

[quote author=E.Ramin link=topic=2501.msg5831#msg5831 date=1434978150]
.. a unit process that appears [b]only[/b] if e.g. ASM1_AN model is chosen ..
[/quote]
If the icon should not be available e.g. for ASM1 then you will need to create a new Palette for ASM1_AN - because they currently use the same.
You can duplicate the "WEST.WWTP.CN.PaletteLib.xml" and call it e.g. "WEST.WWTP.CN.AN.PaletteLib.xml".
In the BlockLib.xml file, point to the new palette for the ASM1_AN instance.

[quote author=E.Ramin link=topic=2501.msg5831#msg5831 date=1434978150]
.. the IconName is set to activated_sludge_unit until I define a new model
[/quote]
No: the IconName property should be unique.

[quote author=E.Ramin link=topic=2501.msg5831#msg5831 date=1434978150]
1.  I have just first copy/pasted the activated_sludge_unit model folder and definition file and renamed them (forlder: ActiveX, msl file: wwtp.base.ABC.msl).
2.  Added the line "#include wwtp.base.ABC.msl" in the wwtp.msl file

However as soon as I refresh the treeview, I get the error "cannot find file: wwtp.base.ABC.msl).
[/quote]
Not sure how you plan to implement your model, but you certainly don't need to duplicate the entire activated_sludge_unit folder. You may want to have a dedicated sub-folder for your new unit process (e.g. "ActiveX"), ok. Then you can save the new files pertaining to your new unit process in ActiveX.
What does the "wwtp.base.ABC.msl" actually implement? Is "ABC" the unit process model? And could "DEF" be a different implementation for the same unit process? If so, then I would imagine the following structure:
[list]
[li]sub-folder ActiveX containing one or more models: ABC, DEF, etc.[/li]
[li]a 'header' file for the new unit process, "wwtp.base.ActiveX.msl" located one level above the folder "ActiveX and containing include statements for ABC, DEF, etc.[/li]
[li]one single include statement (for "wwtp.base.ActiveX.msl") in the rootfile[/li]
[/list]
If you have placed your "wwtp.base.ABC.msl" inside the "ActiveX" folder, the correct include statement should be:
#include "[b]ActiveX/[/b]wwtp.base.ABC.msl"

Sure: please send the whole WESTforOPTIMIZATION folder that you use to mikebydhi@dhigroup.com

[quote author=jfax link=topic=2496.msg5812#msg5812 date=1434361739]
.. some blocks seemingly disappear as that the Block Details window just prompts me: "The model for '.XX' is not available in the Model Library" ..
[/quote]

I assume you are using a custom model (that you have implemented, or modified from a base one).
What you report generally happens when one or more [b]interface variables[/b] are declared (in the interface section) but not assigned or used (in the equations section).

[quote author=jfax link=topic=2496.msg5812#msg5812 date=1434361739]
.. I for example entered a simple P controller for DO but when I start a steady state model it switches to a ratio controller.
[/quote]

This is very weird. Are these the standard models, or again custom ones? and which version are you using: 2014 Sp2?

[quote author=Enrico Remigi link=topic=2492.msg5794#msg5794 date=1433928607]
.. Nitrogen removal in the model i.e  less than 10%, ..
[/quote]

Is it not that you aerated too much (what's the DO in the tanks, especially anoxic)?
Or that you recycle too much of the aerated mixed liquor?

[quote author=Enrico Remigi link=topic=2492.msg5794#msg5794 date=1433928607]
Is it possible to fractionate TKN to Org_N and S_NH by using ASM2d?
[/quote]

Absolutely! The (de)fractionation models (layouts) that are shipped with WEST are only basic options that one can use. But you can certainly modify them  (or create completely new ones) and save them.
Please see another thread on this forum.

Good that you managed to solve this.
But how did it happen that the name (internal name) of the block changed from "SST_1" to "SST_2" ?
This may hide an underlying issue that may pop up at a later stage ..

[moved from "A block (flow splitter) does not receive input?"]

The existing problem now is no Nitrogen removal in the model i.e  less than 10%, I checked the recirculation of flow from deoxic tank to anoxic tank and size of the tanks.  I wonder why? the model works well on removal of COD and TP but not Nitrogen. In the model input, TKN is directly connected to S_NH with fraction ratio of 0.4. Is it possible to fractionate TKN to Org_N and S_NH by using ASM2d?

[quote author=Moses link=topic=2491.msg5788#msg5788 date=1433860473]
Q_In=285702.5 m3/d
Q_Out=285702.5 m3/d
Q_Under_Actual=0 m3/d
[/quote]

If that is the case, then it's perfectly correct that the flow splitter, connected to the sludge extraction terminal of the SST, shows no input.
What is unclear is:
[list]
[li]why do you have Q_Under_Actual = 0 ?[/li]
[li]why is X_In <> X_Out, if X_Under =0 ?[/li]
[/list]
To answer the first question, you should look at how do you set Q_Under (via a controller?) and what are the values?
For the second question: are you working with 2014 Sp2 ? (please check via the "i" blue button, on the top-right corner)

I am not sure I fully understand.
Is it that the flow splitter connected to the underflow of the clarifier does not receive any input - and the bottom layers of the clarifier show zero concentration?
What kind of plant layout are you using? Can you briefly list the values for the key parameters?