Example Class - Check Elemental Balance of a Process Unit Operation

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Example Class to Check Elemental Balance of a Process Unit Operation

Class Class_UnitElemMB
    Textbreak 
    String   UnitName@{Tag}
    String   Element*{Comment("If unspecified, defalut to 'O' for Oxygen")}
    String   Stream, FlowTag
    Real     FlowIn@("Qm", "kg/h"), FlowOut@("Qm", "kg/h")
    Real     MassDiff@@("Qm", "kg/h"), TotFlow 
    integer  Count, inCount@@, outCount@@, i
    Checkbox ElemBal_OK@
	
	Sub Init()
		UnitName = ClassTag()
		if IsEmpty(Element)
		   element = "O"
		Endif	
	EndSub

	Sub Init2()
		if IsEmpty(Element)
		   element = "O"
		Endif	
	EndSub
	
    StrFunction GetStreamName(integer i, String InOrOut)
       return [Concatenate(UnitName,".Links.",InOrOut,".[",IntToStr(i),"].ConnTag")]
    EndFunct	
    
    Function GetFlow(String InOrOut)
        Count   = [Concatenate(UnitName,".Links.Summary.",InOrOut,".Count")]
        TotFlow = 0.0
        i = 1
        while (i <= Count)
            Stream  = GetStreamName(i,InOrOut)
            FlowTag = Concatenate(Stream,".Qo.QEl.",Element," (kg/h)")
            TotFlow = TotFlow + [FlowTag]
            i = i + 1
        EndWhile
        return TotFlow
    EndFunct
    
    Sub CalculateBalance()
        FlowIn     = GetFlow("In")
        inCount    = Count
        FlowOut    = GetFlow("Out")
        outCount   = Count
        MassDiff   = FlowOut - FlowIn
        ElemBal_OK = iif(Abs(MassDiff) < 0.00001, 1, 0)
    EndSub
EndClass

; ---- Using the Class ---- 
PageLabel "ElemBal" 
; Define the required number of Elemental Balance Calculations 
    Class_UnitElemMB   Cementation, AutoclaveLeach_FeedTank, Ni_Co_Filter
    Class_UnitElemMB  # CCD[4]{ez}

Sub InitialiseSolution()
    ForEachClass(Class_UnitElemMB, init())
	CCD[1].UnitName = "CCD_1"
	CCD[2].UnitName = "CCD_2"
	CCD[3].UnitName = "CCD_3"
    ForEachClass(CCD, init2())
EndSub	

; Perform the Elemental Balance Calculations at the end of project solve 
Sub TerminateSolution()
    ForEachClass(Class_UnitElemMB, CalculateBalance())
    ForEachClass(CCD, CalculateBalance())
EndSub

EndFile

NOTES:

1. Example General Controller results for the Nickel Copper Demo Project.

   

2. User may obtain an elemental balance for each unit model by turning on the Audit.On and ElemAudit.On options.

   

3. The example above shows both the class definition and the use of Class in the same PGM file.
   • In general, if the Class is useful for multiple PGM file or can be re-used, it is best to store the class definition in a separate file (e.g.: Gerenal_Class.pgm). The class definition can then be inserted into a PGM file using the include file syntax. (e.g.: >>General_Class.pgm)
   • Please see Sharing Classes between Projects for more information on how to include the class definition into a pgm file.