WaterSolutions Normalization of Membrane Systems ("FTNORM")

It is normal for operating conditions of reverse osmosis and nanofiltration systems to fluctuate causing permeate flow and salt passage to change. To effectively evaluate system performance, comparing permeate flow and salt passage data at the same conditions is vital. Since this is not always possible, converting the actual data conditions to a set of selected normalized conditions is necessary.

Thorough record keeping is required to follow the performance of a membrane system. Good operating data helps with troubleshooting and is also necessary for warranty claims.

Analyzing the data will determine if the membrane system's performance has changed over time. This process is called normalization.

FTNORM - Software to Normalize Membrane Operating Data
In order to help with data collection, Dow offers FTNORM, a spreadsheet-based program. The program is Microsoft^® Excel 97^® based and provides for automatic standardization of operating data. Charts are created showing standardized permeate flow, standardized salt passage / salt rejection and differential pressure. One spreadsheet should be used for each train in the system.

Downloading FTNORM
FTNORM spreadsheets are available in U.S. and metric units for One-Stage or Two-Stage systems. Choose the option appropriate to your system and download before proceeding.

One-stage system:
	US Units (gpm – psig)
	Metric Units (m3/hr – bar)
	Metric Units (m3/hr – kgcm2)
Two-stage system:
	US Units (gpm – psig)
	Metric Units (m3/hr – bar)
	Metric Units (m3/hr – kgcm2)

1. Download and open the FTNORM spreadsheet.
2. At the top of the spreadsheet, enter the "plant identification" and "start-up date" in the designated cells.
3. The cells requiring data entry contain red lettering. Blue lettering is used for calculated values.
4. The operating data is entered beginning in row 11 with the date. Overwrite the existing sample data. The equations performing the standardization calculations will allow approximately one year (365 days) of data entry. You will need to copy the equations for each column when additional operating data is entered.
5. When data entry is completed, save the spreadsheet using a unique name associated with the train.

Graphing Data
The charts in the template are designed to show the first five data points in cells 11 through 15. As additional data is entered, update the chart using the chart/source data portion of the menu. In this section, you will increase the maximum values for the X-axis and Y-axis to reflect the operating data entered. This will update the chart to include the new data.