WasteWater.ASM1.SecClar.Simple

Information

This package just provides a very simple ASM1 secondary clarifier model
with no sludge storage, no sludge sedimentation and no use of layers.
The model consists of one tank removing all particulate substances.

Main Author:
 
          Gerald Reichl
          Technische Universitaet Ilmenau
          Faculty of Informatics and Automation
          Department Dynamics and Simulation of ecological Systems
          P.O. Box 10 05 65
          98684 Ilmenau
          Germany
          email: gerald.reichl@tu-ilmenau.de

Copyright (C) 2002, Gerald Reichl

The Modelica package is free software; it can be redistributed and/or modified under the terms of the Modelica license, see the license conditions and the accompanying disclaimer in the documentation of package Modelica in file "Modelica/package.mo".

WasteWater.ASM1.SecClar.Simple.SimpleSecClarMod

Information

This component models very simple the secondary clarification process by
just using a single fully mixed tank which removes all particulate substances from the effluent
and returns the sludge. No sedimentation and compression, etc. is considered (for ASM1).

Parameters

Name	Default	Description
hsc	4.0	height of secondary clarifier [m]
Asc	1500.0	area of secondary clarifier [m2]

Modelica definition

model SimpleSecClarMod "Simple ASM1 Secondary Clarifier Model" 
  
  extends WasteWater.Icons.SecClarSimple;
  extends WasteWater.ASM1.SecClar.Takacs.Interfaces.ratios;
  package SI = Modelica.SIunits;
  package WI = WasteWater.ASM1.Interfaces;
  package WWU = WasteWater.WasteWaterUnits;
  
  parameter SI.Length hsc=4.0 "height of secondary clarifier";
  parameter SI.Area Asc=1500.0 "area of secondary clarifier";
  
  WWU.MassConcentration Xf "total sludge concentration in clarifier feed";
  WWU.MassConcentration X "sludge concentration in clarifier";
  WWU.MassConcentration Si "Soluble inert organic matter";
  WWU.MassConcentration Ss "Readily biodegradable substrate";
  WWU.MassConcentration So "Dissolved oxygen";
  WWU.MassConcentration Sno "Nitrate and nitrite nitrogen";
  WWU.MassConcentration Snh "Ammonium nitrogen";
  WWU.MassConcentration Snd "Soluble biodegradable organic nitrogen";
  WWU.Alkalinity Salk "Alkalinity";
  
  WI.WWFlowAsm1in Feed;
  WI.WWFlowAsm1out Effluent;
  WI.WWFlowAsm1out Return;
  WI.WWFlowAsm1out Waste;
equation 
  
  // total sludge concentration in clarifier feed
  Xf = 0.75*(Feed.Xs + Feed.Xbh + Feed.Xba + Feed.Xp + Feed.Xi);
  
  // ratios of solid components
  rXs = Feed.Xs/Xf;
  rXbh = Feed.Xbh/Xf;
  rXba = Feed.Xba/Xf;
  rXp = Feed.Xp/Xf;
  rXi = Feed.Xi/Xf;
  rXnd = Feed.Xnd/Xf;
  
  // ODE of sludge concentration
  der(X) = (Feed.Q*Xf - (-(Waste.Q + Return.Q))*X)/(Asc*hsc);
  
  // ODE of soluble components
  der(Si) = (Feed.Q*Feed.Si - (-Effluent.Q)*Si - (-(Waste.Q + Return.Q))*Si)/(Asc*hsc);
  der(Ss) = (Feed.Q*Feed.Ss - (-Effluent.Q)*Ss - (-(Waste.Q + Return.Q))*Ss)/(Asc*hsc);
  der(So) = (Feed.Q*Feed.So - (-Effluent.Q)*So - (-(Waste.Q + Return.Q))*So)/(Asc*hsc);
  der(Sno) = (Feed.Q*Feed.Sno - (-Effluent.Q)*Sno - (-(Waste.Q + Return.Q))*Sno)/(Asc*hsc);
  der(Snh) = (Feed.Q*Feed.Snh - (-Effluent.Q)*Snh - (-(Waste.Q + Return.Q))*Snh)/(Asc*hsc);
  der(Snd) = (Feed.Q*Feed.Snd - (-Effluent.Q)*Snd - (-(Waste.Q + Return.Q))*Snd)/(Asc*hsc);
  der(Salk) = (Feed.Q*Feed.Salk - (-Effluent.Q)*Salk - (-(Waste.Q + Return.Q))* Salk)/(Asc*hsc);
  
  // volume flow rates
  Feed.Q + Effluent.Q + Return.Q + Waste.Q = 0;
  
  // effluent, solid and soluble components (ASM1)
  Effluent.Si = Si;
  Effluent.Ss = Ss;
  Effluent.Xi = 0.0*X;
  Effluent.Xs = 0.0*X;
  Effluent.Xbh = 0.0*X;
  Effluent.Xba = 0.0*X;
  Effluent.Xp = 0.0*X;
  Effluent.So = So;
  Effluent.Sno = Sno;
  Effluent.Snh = Snh;
  Effluent.Snd = Snd;
  Effluent.Xnd = 0.0*X;
  Effluent.Salk = Salk;
  
  // return sludge flow, solid and soluble components (ASM1)
  Return.Si = Si;
  Return.Ss = Ss;
  Return.Xi = rXi*X;
  Return.Xs = rXs*X;
  Return.Xbh = rXbh*X;
  Return.Xba = rXba*X;
  Return.Xp = rXp*X;
  Return.So = So;
  Return.Sno = Sno;
  Return.Snh = Snh;
  Return.Snd = Snd;
  Return.Xnd = rXnd*X;
  Return.Salk = Salk;
  
  // waste sludge flow, solid and soluble components (ASM1)
  Waste.Si = Si;
  Waste.Ss = Ss;
  Waste.Xi = rXi*X;
  Waste.Xs = rXs*X;
  Waste.Xbh = rXbh*X;
  Waste.Xba = rXba*X;
  Waste.Xp = rXp*X;
  Waste.So = So;
  Waste.Sno = Sno;
  Waste.Snh = Snh;
  Waste.Snd = Snd;
  Waste.Xnd = rXnd*X;
  Waste.Salk = Salk;
  
end SimpleSecClarMod;