Developmentof Empirical Model for Trade Waste Discharges to Small Treatment Plants

 Report No WSAA 18

November 1990




Thisproject has identified the availability of the computer model ‘PRELIM’,developed on behalf of the US EPA from several major studies. This steady statemodel is designed to protect the particular treatment plant under study and canbe run on an IBM compatible PC utilising a DOS operating environment. Theprogram can estimate the maximum allowable loads of various pollutants fromindustries that can be accommodated by a treatment facility, whilst ensuringplant compliance with the applicable disposal criteria which may limit eachpollutant.


Userscan select the treatment processes, disposal criteria and inhibition data tosuit their particular application. The program also incorporates extensivedefault value data bases for process removal efficiencies, inhibition data andvarious industry effluent characteristics, although system specific dataavailable through sampling and analytical programs are recommended for moreaccurate results. After making allowance for domestic contributions andsafety/future growth factors, the model will compare estimated availablepollutant loads with actual measured industrial trade waste discharges.


Underthis project, the PRELIM model has been adapted for use in Australia by:


-                   Replacement of US terminology with Australian terminology


-                   Conversion of the program to run on SI metric units


-                   Expansion and revision of the default pollutants schedule and databases to more closely reflect Australian conditions


-                   Enhancement of the model to include pollutant inhibition in tricklingfilter plants


-                   Modification of the program output routines to allow more efficientcomputer use and more convenient operation


-                   Amendment of the Users Guide to reflect the above.


Aspart of the Australian verification of the revised program, calibrated modelswere developed for three Mornington Peninsula & District Water Board(MPDWB) plants (activated sludge/biofiltration/aerated lagoons). However,budgetary limitations have pre-empted full calibration and verification ofthese models.


Seealso Report No. WSAA 19


Copiesof the Report are available from WSAA, price $A40. Orders may be placed throughthe Bookshop at or by email to