TM 10-4610-232-12
Figure 2-45. Sequestrant Set-Up
(a)
Fill sequestrant tank (1) half full with product water, using product utility hose. Turn sequestrant pump on.
(b)
Set speed control knob (2) to 80 and record.
(c)
Set stroke control knob (3) to 100 and record.
(d)
Pull out and hold priming knobs (4) until water is being pumped out through discharge tubing to drain.
(e)
Measure sequestrant into tank. The quantity to be transferred depends on water source. See Table 2-21.
NOTE
Sequestrant alone causes an increase in the growth rate of bacteria on the RO membranes.
Bisulfite is added to counteract this growth.
(f)
If sequestrant is added, also add one large 2 lb (.9 kg) bag of bisulfite.
(g)
Fill tank to full level (number 12 on scale) with product water and vigorously mix with mixing paddle for two minutes.
By visual observation, make sure all sequestrant is in solution. Use caution when mixing to avoid hitting fittings and
switches in tank.
(h)
Reset stroke control knob (3) to 40 and record.
Table 2-21. Sequestrant Concentration
Amount of
Sequestrant
Water Source/Condition
to be Used
Fresh surface water with under
500 ppm TDS
None*
Surface waters with over
500 ppm TDS
18 oz (1-1/2 oz per gal.)
Sea water
18 oz (1-1/2 oz per gal.)
Persian Gulf and Red Sea
36 oz (3 oz per gal.)
Well waters:
Europe or North America
None*
All others
36 oz (3 oz per gal.)
*For water sources that do not require sequestrant, fill tank with product water to
just above level switch so that yellow light on control panel goes off. Make sure
pump speed switch is off.
Change 12 2-81
