MIOX RIO-S Series Operators Manual
102-00130-D
Page
71
t = 0
0.4
12:00 2.1
12:05 4.0
12:10
t + 30 min.
0.08 12:30 2.0
12:35 2.5
12:40
t + 60 min.
0.0 1:00 2.0 1:05 2.5 1:10
t + 90 min.
0.0 1:30 1.8 1:35 2.4 1:40
Oxidant Demand Determination
After 90 minutes, determine which sample has the FAC residual nearest to the desired
residual specified by the water system operator. If a desired residual is unknown, look for a
FAC slightly greater than 0.2 ppm, which is usually the standard required by the state.
Subtract the selected FAC reading from the initial FAC dose for the corresponding sample.
This signifies how much of the oxidants were consumed by the water and thus how much of
an oxidant demand there is in the sample water.
Example:
Determine the oxidant demand of the water. In this case, let’s assume the operator wants a
1.0 FAC residual in the water system. Looking at the bottom row (t + 90 minutes) of the
chart filled out above, note that Sample B at 1.8 ppm is closest to the desired residual. The
initial FAC dose in this case was 3 ppm, so the oxidant demand of this water is 1.2 ppm (3.0
- 1.8 = 1.2). (This means that the operator must dose at 2.2 ppm (1.2 + 1.0 = 2.2) to
achieve his desired residual of 1.0 ppm.
Chlorine Production Testing
Calculating chlorine production alone is the easiest way of checking the performance of a
MIOX mixed-oxidant or MIOX sodium hypochlorite system. A cell yielding a reading of 3200
ppm when it should be reading 3600 ppm may not be old and depleted -- the flows may
also be high.
Total Chlorine Production = Chlorine Concentration X Volumetric Flow per
unit time
Follow the steps below to correctly determine the total chlorine production of the system.
Equipment Needed
• 250 mL glass beaker
• 3000 mL, or 5000 mL glass jar with lid (depending on MIOX OSG being tested)
• Pipette that can accurately measure 0.5 mL or 1 mL samples
• Chlorine Test Kit (i.e. DPD, Color Wheel, Colorimeter or AccuVac)
• Chlorine Demand-Free Water (see below)
