INTRODUCTION.
A15/79 Total Chlorine Monitor uses the standard iodometric
method for the determination of total chlorine in highly contaminated
samples. A unique sensing technique is used to determine total chlorine concentration,
while minimizing system maintenance requirements. The system takes the
reacted sample containing iodine and uses a membraned gas sensor rather than
exposed electrodes. The gas permeable membrane allows only iodine to permeate
into the sensor. Sample contaminants are eliminated from coming in contact with
measuring electrodes, providing better stability and reducing sensor
maintenance. This method is ideal for very low range measurement of
dechlorinated wastewater, where biological growth from sulfur reducing bacteria
can cause severe fouling problems in contact systems.
This system brings a
sample of water to the chemistry module where pH 4 buffer and potassium iodide
solutions are added. All of the various chlorine compounds in the sample
water react with the iodide to form an equivalent amount of molecular iodine.
The reacted sample then enters an air-stripping chamber where the
released iodine is stripped from the sample, with the resulting air stream
directed to the iodine gas sensor located in a separate chamber. A
membrane across the face of the sensor allows iodine to diffuse to the active
electrode surface. Iodine is reduced to iodide, generating a current
proportional to total chlorine concentration.
Chlorination of
potable water, wastewater effluent, and cooling water is widely used throughout
the world to control biological activity in the water. Disinfection of potable
water with chlorine ensures that tap water is safe to drink once it has passed
through the distribution system. Wastewater disinfection helps to ensure that
receiving streams are safe for recreational use, and cooling water chlorination
reduces biofouling that can degrade heat transfer efficiency. In addition to
these common uses, there are many other applications where chlorine addition
helps to reduce biological contamination.
Want to learn more about our A15/79 Total Chlorine Monitor?
Click the "Product Literature" link above the product image.