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WATER9, Version 3.0

**The WATER9 model was developed using a software that is now outdated. Because of this, the model is not reliably functional on computers using certain operating systems such as Windows Vista or Windows 7. We are anticipating that additional problems will arise as PCs switch to the other operating systems. Therefore, we can no longer provide assistance to users of WATER9. The model will remain on the website to be used at your discretion and at your own risk.

Description and Background

Released June 29, 2006
(This program supersedes WATER8, Chem9, and Chemdat8, and WATER9 version 1.0)

Version 3.0 is an update and upgrade to the previous version.

WATER9, the wastewater treatment model, is a Windows based computer program and consists of analytical expressions for estimating air emissions of individual waste constituents in wastewater collection, storage, treatment, and disposal facilities; a database listing many of the organic compounds; and procedures for obtaining reports of constituent fates, including air emissions and treatment effectiveness.

WATER9 is a significant upgrade of features previously obtained in the computer programs WATER8, Chem9, and Chemdat8. WATER9 contains a set of model units that can be used together in a project to provide a model for an entire facility. WATER9 is able to evaluate a full facility that contains multiple wastewater inlet streams, multiple collection systems, and complex treatment configurations. WATER9 provides separate emission estimates for each individual compound that is identified as a constituent of the wastes. The emission estimates are based upon the properties of the compound and its concentration in the wastes. To obtain these emission estimates, the user must identify the compounds of interest and provide their concentrations in the wastes. The identification of compounds can be made by selecting them from the database that accompanies the program or by entering new information describing the properties of a compound not contained in the database.

WATER9 has the ability to use site-specific compound property information, and the ability to estimate missing compound property values. Estimates of the total air emissions from the wastes are obtained by summing the estimates for the individual compounds.

The EPA document, AIR EMISSIONS MODELS FOR WASTE AND WASTEWATER includes the equations used in the WATER9 model. 

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WATER9 Files for version 3

WATER9 Version 3 Changes and Documentation

Changes to WATER9 Version 3

WATER9 version 3 is an update and an upgrade of the previous version of WATER9. New features have been added to improve the use of WATER9.

Upgrades include:

-More extensive reporting of results,
-floating roof model capability was expanded,
-update of stripping/mixing ratio,
-capability to load a project from a set of recent projects,
-model multiple DAF units in parallel,
-biological removal in a DAF unit,
-capability to specify mass transfer coefficient,
-an updated project manual in a compiled help file,
-updated context sensitive help during WATER9 use,
-improved project editing,
-improved waste spreadsheet editing,
-enhanced recycle capability and property editing,
-additional compounds in the data base,
-upgraded compound property search procedures, and
-additional unit types for modeling.

Corrections to WATER9 include:

-Incorrect Acetone pKa specification,
-error for very low water content of waste stream,
-problem with cooling tower blow down for some units, and
-reviewed and updated compound properties.
Additional information for features, upgrades, and error correction is available in WATER9 under the menu item "Upgrade information"

Example Scenarios(549 K, 6/29/2006)

Example scenario files contain information that will assist you in modeling units with WATER9. A series of example scenarios are provided in the guidance files. Topics include:
-general guidance,
-concentrated animal feeding operations,
-municipal treatment with recycle,
-external operations (emissions elsewhere, results merged with WATER9),
-open pipe discharge,
-cross flow cooling tower,
-collection system elements, and
-floating roof tank.

Each guidance topic typically includes:
-an example project,
-a discussion of the technical approach,
-the use of input parameters, and
-comparisons of the model results with measured results (validation).
These guidance files may be used from the WATER9 main menu, or they may be used independently as a Windows help file. If you wish to use these scenarios in WATER9, you must save them to the WATER9 folder that you create when you download the model. You may print the information, search for a topic, or use the contents file.

WATER9 Training Video

An WATER9 Training Video(38 MB, 2006)  (ZIP 38M) can be downloaded to your PC. Copy the ZIP file to a folder on your PC. Unzip all of the files to the folder and double click on the file Water9Complete.html. You will need Adobe Flash Player in order to view the movie.

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