50 Process Economics Review
Important Equations
Total Capital Investment | TCI=FCI+WCTCI=FCI+WC |
Effect of capacity on equipment prices | CaCb=(AaAb)nCaCb=(AaAb)n
ln(Ca)=ln(K)+nln(Aa)ln(Ca)=ln(K)+nln(Aa) |
Effect of time on equipment prices | C2=C1(I2I1)C2=C1(I2I1) |
Preliminary Estimation of Purchased Equipment Costs | Ce=a+bSnCe=a+bSn |
Lang Factor | CTM=Flang∑ni=1Cp,iCTM=Flang∑ni=1Cp,i |
Return on Investment | ROI=revenue−COMTCI×100%ROI=revenue−COMTCI×100% |
Revenue | revenue=unitpriceofproduct×salesrevenue=unitpriceofproduct×sales |
Cost of manufacturing | costofmanufacturing=directcost+fixedcost+generalexpensescostofmanufacturing=directcost+fixedcost+generalexpenses |
Number of operating labour | NOL=(6.29+31.7P2+0.23Nnp)0.5NOL=(6.29+31.7P2+0.23Nnp)0.5 |
Cost of operating labour | # of operators=NOL×# of shifts in a year# of shifts per operator# of operators=NOL×# of shifts in a year# of shifts per operatorCOL=# of operators×salaryCOL=# of operators×salary |
Total direct cost of manufacturing | total direct cost of manufacturing=CRM+CWT+CUT+1.33COL+0.03COM+0.069FCItotal direct cost of manufacturing=CRM+CWT+CUT+1.33COL+0.03COM+0.069FCI |
Total fixed cost of manufacturing | total fixed cost of manufacturing=0.708COL+0.068FCI+depreciation(0.1FCI)total fixed cost of manufacturing=0.708COL+0.068FCI+depreciation(0.1FCI) |
Depreciation | depreciation=purchased value−salvage valuelife of equipment (n)depreciation=purchased value−salvage valuelife of equipment (n) |
General expenses | general expenses=0.177COL+0.009FCI+0.16COMgeneral expenses=0.177COL+0.009FCI+0.16COM |
Cost of manufacturing | cost of manufacturing=0.180FCI+1.23(CRM+CWT+CUT)+2.73COL+depreciation(0.1FCI) |
Feedback/Errata