GPS-X Technical Reference

361 Operating Cost Models
CHAPTER 13
Operating Cost Models
INTRODUCTION
GPS-X contains operating cost models for most of the objects in the process table. Each object
can be set up to calculate costs for energy, chemical dosage and sludge handling (as appropriate
to that object).
This chapter discusses the structure of the operating cost models, and their use and calibration.
MODEL STRUCTURE
For each of the wastewater unit process objects in GPS-X, a set of operating costs has been
assigned. These costs reflect the typical operating costs associated with that particular unit
process.
GPS-X can be used to dynamically simulate these operating costs in the same way that it
dynamically simulates the wastewater unit process itself.
The 5 different types of operating costs modelled are:
Aeration energy cost
Pumping energy cost
Miscellaneous energy cost
Chemical dosage cost
Sludge handling cost
The following sections described each cost in detail.
Aeration Energy Cost
An aeration energy cost can be calculated for unit processes that have aeration, such as
the CSTR, plug flow tanks, SBR, etc. The amount of energy required to supply the
calculated level of aeration depends on several factors, including blower/compressor
efficiency, headloss, etc., and the factors included in the oxygen transfer model (See
Modelling of Oxygen Transfer in Chapter 6).
GPS-X Technical Reference