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TheBlueprintof Water

Weigh the dose, read the rise. The volume nobody documented falls out.

Operating Case

Enter your system parameters. Results update automatically.

TracerPTSA on a fluorometer, molybdate on a test kit, or plain salt by chloride titration. Same dilution equation throughout.
System TypeOnly affects the notes shown and which calculators offer to receive the result.
System volume≈ 13,200 gal 50,000 L
Standard tracer concentrate is about 10% PTSA. Read the label.
%

% active PTSA, off the label.

Weigh it if you can; a $20 scale beats a graduated cylinder. If measuring by volume, enter the specific gravity (about 1.05 for a 10% solution).
g
Specific gravity of the tracer solution, used only for a dose by volume.
SG

Only used for a dose by volume.

Reading before dosing, on the system water with the feed paused. Loops on a moly program start high; dose enough to rise 5 to 10 ppm above kit noise.
ppb

Feed paused, before the dose.

Stable reading after full circulation. Two readings in a row within about 5%.
ppb

ppb PTSA, not ppb of a product.

Optional. The classic estimate is three times the recirculation rate; enter it to see how far the rule sits from the measurement.
gpm

Optional, for the rule of thumb.

Click on any stream to learn more.

Volume by Tracer Dilution

All quantities are live and update with your inputs.

Operating Conditions
Tracer
PTSA
System
Cooling tower
Added
50.0 g
Background
0 ppb
After
100 ppb
Recirc
none

Key Results

Primary outputs and operational context based on your inputs.

Based on a rise of 100 ppb; a ±1 ppb reading error changes this by ±1.0%.

System Volume The dilution solved backward, to three significant figures.

13,200 gal

13,209 gal unrounded, 50,000 L

PTSA into a cooling tower, to three significant figures.

Tracer Added The active tracer that went in, on the basis the kit reads.

5.00 g PTSA

50.0 g as added

Solution grams times the active fraction.

Rise After mixing less background, in the reading's unit.

100 ppb

0 → 100 ppb

Clear of the 1 ppb resolution.

Uncertainty What a one-resolution reading error does to the answer.

±1.0 %

per 1 ppb of reading error

About ±132 gal either way.

Rule of Thumb Three times the recirculation rate, the tower rule of thumb.

n/a

enter a recirculation rate

The classic estimate is three times the recirculation rate.

Before You Trust It The procedure decides whether the number is right.
  • Towers: stop the blowdown for the test. Blowdown removes tracer and makes the system look bigger.
  • Wait for full mixing. Towers 15 to 30 minutes, large loops an hour or more, two readings within 5%.
  • Read the background first with the feed paused, and subtract it.

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