Wastewater Library

ADM1

Submodel

Provides the required variables, parameters, and equations to initialize an anaerobic digester model that uses the Anaerobic Digestion Model No. 1 (ADM1) reactions to calculates changes in organic carbons, hydrocarbons, and associated biomass. After you initialize the reactor, you can replace the ADM1 reaction submodel in the anaerobic digester with a custom reaction submodel with actual reaction rates for your process.

ADM1BiochParam

Submodel

Provides the biochemical parameter calculation for the ADM1 model.

ADM1GasTransfer

Submodel

Serves as a replaceable submodel that calculates the biogas transfer rate from an anaerobic digester.

ADM1PChParam

Submodel

Provides the physico-chemical parameter calculation for the ADM1 submodel.

ADM1Stoichiometry

Submodel

Provides the stoichiometric parameter values for the ADM1 submodel.

AerationTank

Model

Represents a continuously stirred tank reactor (CSTR) for biological wastewater treatment in the presence of oxygen.

An aeration tank converts its feed stream composition, which is mainly organic matter (chemical oxygen demand (COD)) and a nitrogen source (ammonia and nitrite), into a product stream composition based on component reaction rates per volume. The component reaction rates are expressed through stoichiometric relations and a formulation for the wastewater reaction kinetics.

You must provide the expression for the reaction rates through a replaceable reaction submodel in the model’s Fluid Type. Ideally, you would have a custom Wastewater FluidType and custom reaction submodel in the simulation-specific Model Library that you could then use in the AerationTank model.

By default, the AerationTank model uses the ASM3 reaction submodel, which sets all component reaction rates to default values, and the DefAeration aeration submodel, which applies the oxygen in the reactions.

AnaerobicDigester

Model

Represents a CSTR for the biological degradation of organic matter in wastewater sludge and the subsequent generation of biogas during the hydrolysis and digestion reactions. It uses the replaceable reaction submodel specified in the RxnModelType parameter for its reaction kinetics. The default value for this parameter is the ADM1 reaction submodel from the Wastewater Library.

AnoxicTank

Model

Represents a CSTR for biological wastewater treatment with no aeration.

An anoxic tank converts its feed stream composition, which is mainly organic matter (COD) and a nitrogen source (nitrite and nitrate), into a product stream composition based on component reaction rates per volume. The component reaction rates are expressed through stoichiometric relations and a formulation for the wastewater reaction kinetics.

You must provide the expression for the reaction rates through a replaceable reaction submodel in the model’s Fluid Type. Ideally, you would have a custom wastewater Fluid Type and custom reaction submodel in the simulation-specific Model Library that you could then use in the AerationTank model.

By default, the AnoxicTank model uses the ASM3 reaction submodel, which sets all component reaction rates to default values.

ASM3

Submodel

Provides the required variables, parameters, and equations to initialize a wastewater reactor that uses the ASM3 reactions to calculate changes in biomass. After you initialize the reactor, you can replace the ASM3 reaction submodel in the reactor with a custom reaction submodel with actual reaction rates for your process.

ASM3Base

Submodel

Serves as a replaceable reaction submodel for the ASM3 reactions that calculate changes in biomass.

You can use this reaction submodel in a Wastewater Fluid Type as the Base reaction submodel when you set the Reaction model for the Fluid Type to the ASM3Modular submodel from the Wasterwater Library.

ASM3CO2Ext

Submodel

Serves as a replaceable reaction submodel for the ASM3 reaction extension that calculates carbon dioxide (CO2) production.

You can use this reaction submodel in a Wastewater Fluid Type as the CO2 production reaction extension submodel when you set the Reaction model for the Fluid Type to the ASM3Modular submodel from the Wasterwater Library.

ASM3GHG

Submodel

Serves as a replaceable reaction submodel for the ASM3 reaction extension that calculates both nitrous oxide (N2O) and CO2 production, which are greenhouse gases.

You can use this reaction submodel in a Wastewater Fluid Type as the CO2 production reaction extension submodel when you set the Reaction model for the Fluid Type to the ASM3Modular submodel from the Wasterwater Library.

ASM3KineticParam

Submodel

Provides the kinetic parameter calculation for the ASM3 submodel.

ASM3Modular

Submodel

Serves as a replaceable reaction submodel that allows you to customize the ASM3 reaction calculations that are used in a Wastewater Fluid Type. This submodel includes a base reaction submodel and options to extend the base reaction submodel with a N2O production submodel, a phosphorous removal submodel, and a CO2 production submodel.

You should use this submodel as the Reaction model only for a Fluid Type with a Thermo Type of Wastewater.

ASM3N2OExt

Submodel

Serves as a replaceable reaction submodel for the ASM3 reaction extension that calculates N2O production.

You can use this reaction submodel in a Wastewater Fluid Type as the N2O production reaction extension submodel when you set the Reaction model for the Fluid Type to the ASM3Modular submodel from the Wasterwater Library.

ASM3P

Submodel

Serves as a replaceable reaction submodel for the removal of biological phosphorous. This submodel includes both the reaction rates for the regular ASM3 changes in biomass and the Activated Sludge Model No. 3, Bio-P (ASM3P) reaction extension that calculates changes in ortho-phosphate (PO4) and associated biomass.

ASM3PExt

Submodel

Serves as a replaceable reaction submodel for the removal of biological phosphorous. This is the ASM3P reaction extension that calculates changes in PO4 and associated biomass. There are no reactions (reaction rates are zero) in this submodel.

You can use this reaction submodel in a Wastewater Fluid Type as the Phosphorous removal reaction extension submodel when you set the Reaction model for the Fluid Type to the ASM3Modular submodel from the Wasterwater Library.

ASM3PKineticParam

Submodel

Provides the kinetic parameter calculation for the ASM3P submodel.

ASM3Stoichiometry

Submodel

Provides the stoichiometric coefficient calculations for the ASM3 submodel.

Clarifier

Model

Models a solid separator based on mass balances (without holdup). It uses recovery factors to model residual sludge in the effluent overflow and solute species in the sludge underflow.

ClarifierRig

Model

Provides a discretized model for a secondary clarifier ("Takacs clarifier") to model the sludge precipitation dynamics and the solids retention time (SRT) in the wastewater treatment process.

The ClarifierRig model uses the replaceable submodel specified in the VelType parameter to define the settling velocity model. This allows you to create custom settling velocity submodels that you can then use in the ClarifierRig.

DefAeration

Submodel

Provides the required variables, parameters, and equations to introduce oxygen into the reactions for an aerated wastewater reactor. After you initialize the reactor, you can replace the DefAeration reaction submodel in the reactor with a custom reaction submodel with actual reaction rates for your process.

DefFractionation

Submodel

Serves as the default replaceable submodel model for fractionation in the ASM3 reaction submodel. This submodel converts measurable COD, ammonia, and alkalinity to particulate (X) and solute (S) mass concentrations. We have designed this submodel for use with the ASM3 reaction submodel in anoxic or aeration tanks.

EqTank

Model

Models an equalization tank that provides hydraulic and pollutant load buffering for downstream processes. This model evens out fluctuations in flow and composition of influent wastewater. It stores excess wastewater during peak times, releases the excess gradually during off-peak times, and blends different wastewater streams to create a uniform composition. These operations help optimize downstream treatment processes by stabilizing flow rates and composition, which improves treatment efficiency and effectiveness.

FluidChangeADAS

Submodel

Translates the component list for an ADM1-based fluid to the component list for an ASM3-based fluid.

FluidChangeASAD

Submodel

Translates the component list for an ASM3-based fluid to the component list for an ADM1-based fluid.

FractionationGHG

Submodel

Serves as a replaceable submodel model for fractionation in the ASM3GHG reaction submodel. This submodel converts measurable COD, ammonia, and alkalinity to particulate (X) and solute (S) mass concentrations. We have designed this submodel for use with the ASM3GHG reaction submodel in anoxic or aeration tanks.

FractionationNP

Submodel

Serves as a replaceable submodel model for fractionation in the ASM3P reaction submodel. This submodel converts measurable COD, ammonia, phosphorous, and alkalinity to particulate (X) and solute (S) mass concentrations. We have designed this submodel for use with the ASM3P reaction submodel in anaerobic, anoxic, or aeration tanks.

Inflow

Model

Defines observable measurements of a typical municipal wastewater, such as flow, COD, ammonia concentration, and alkalinity concentration.

Layer*

Submodel

Provides the variables and equations for each layer in the ClarifierRig model.

Mix

Model

Combines multiple feed streams into one product stream. It imposes a pressure balance on all streams in all modes.

NoRxn

Submodel

A replaceable reaction submodel that includes no reactions to temporarily remove reactions from a model. You can use this reaction submodel in a Wastewater Fluid Type to turn off any of the reaction extensions when you set the Reaction model for the Fluid Type to ASM3Modular submodel from the Wasterwater Library.

Outflow

Model

Identifies treated products and waste leaving the process.

pH

Submodel

Serves as the replaceable reaction submodel that calculates the pH based on the equilibrium ion molal concentration of hydrogen for any wastewater stream that contains the alkalinity variable (S[Alk]). The ionic species in this reaction submodel are available in the Chemicals Fluid Type in the Wastewater Library.

pHADM

Submodel

Serves as a replaceable reaction submodel that calculates the pH, free ammonia, and carbon dioxide based on the equilibrium ion molal concentrations for the sludge stream that contains the inorganic carbon (S[“SIC”]) and inorganic nitrogen (S[“SIN”]) variables. The ionic species in this reaction submodel are available in the Chemicals Fluid Type in the Wastewater Library.

Plantwide

Model

Provides a central location for calculating and viewing the SRT for up to 10 subsections and the total SRT for the wastewater process. You can specify the section parameters of the equipment for each section, and then observe the SRT values in the Plantwide model.

Pump

Model

Models a dynamic pump (for example, a centrifugal or axial pump). This model uses performance curves to relate pressure rise and brake power to flowrate. It also uses affinity laws (fan laws) or multi-curve interpolation to calculate the effects of speed or impeller diameter on the performance curve.

Recycle

Model

Improves the convergence of a recycle loop through iterative sequential updates rather than by solving it simultaneously. This method is commonly known as tearing. Sometimes tearing may help difficult convergence problems solve.

SettlingParams*

Submodel

Provides the settling parameters for the ClarifierRig model.

Split

Model

Models a stream splitter that allows one feed stream and multiple product streams. This model imposes a pressure balance on all streams in all modes.

Stream*

Submodel

Reports stream properties. For simulations created with the Wastewater simulation template, the simualtion automatically uses this model as the connection model for streams. This model calculates all variables based on the actual direction of flow.

TakacsVelocity

Submodel

Represents a settling velocity submodel based on Takacs that you can use in a ClarifierRig model. This submodel expects to be given an input solids concentration (Xj) and calculates a settling velocity (X) as an output. You can copy this submodel to the simulation-specific Model Library and then edit them to create your custom settling velocity submodels.

Trans

Model

Represents a transmitter that can connect to a Proportional-Integral-Derivative (PID) or other control model.

VesilindVelocity

Submodel

Represents a settling velocity submodel based on Vesilind that you can use in a ClarifierRig model. This submodel expects to be given an input solids concentration (Xj) and calculates a settling velocity (X) as an output. You can copy this submodel to the simulation-specific Model Library and then edit them to create your custom settling velocity submodels.