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Features
·
Guaranteed Longest Lasting
Sensors Available with performance guarantee *
·
Sensors are compatible with most
existing pH/ORP Meters, Transmitters & Analyzers **
·
Application Specific Engineering
results in optimum Lifetime & Performance ***
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Integrated Temperature
Compensation, Preamplifiers & Solution Ground Elements
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Solid State Reference System offers superior resistance to Fouling
& Dehydration
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Applications such as Acid/Fluoride,
Hi-Temp, Saturated Sodium and Sulfide Resistant are available as standard
options
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Custom Applications are available,
often at no additional charge
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Most Installation Styles are
Supported Including: Immersion, Twist Lock, Valve Retractable
& Sanitary
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Available in a wide range of plastics,
from cost effective CPVC to thermally & chemically resilient ULTEM®
and PEEK thermoplastic
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High Pressure Applications up to
100 psi for Valve Retractable & 150 psi for Inline Installations can be
supported for continuous use
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Operating Temperatures from -30
to +150 ºC (-22 to +302 ºF) can be supported
for continuous use
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Case Study No. 13 – Fluoride
Ion Monitoring in Drinking Water and Water Applications (or non Acid/Etching
Wastewater)
Online Fluoride Ion
Monitoring for Water Districts and other Water Authorities
Simple to use inline fluoride
ion monitoring system operates just as easily as any inline low flow pH
system
Reliable menu driven Industrial
Ion Selective Analyzer calibrates, displays, outputs and controls all in fluoride
ppm units
Inline fluoride ion sensor is completely
sealed from both sides and requires no chemical addition -- unlike many
popular competing sampling fluoride analyzers
The Problem
A
water district was required to monitor the levels of fluoride in the city
drinking water supply. If the levels were too low, fluoride was required to
be added. If fluoride levels were too high, fluoride must be removed.
Because of the natural temperature variance at the measurement point, the
existing sampling fluoride analyzer gave erratic results. The constant
requirement of adding reagents to the sampling analyzer placed a high burden
on the busy maintenance staff, and resulted in reduced plant efficiency.
When the problems with the sampling fluoride analyzer could not be addressed,
grab sample analysis was used. The use of constant grab sample during times
of problems with the online equipment created an undue burden on the
maintenance staff, and defeated the purpose of having an online fluoride
monitoring system.
Since
multiple measurement points were required, a complex system of piping was
installed to deliver sample to the few sampling analyzer available. One a
few sampling analyzer were installed due to their prohibitively high cost.
This caused the two fold problem of a delay in the measurement due to the piping
of the sample to the analyzer (not real time) and the centralization cause
the entire system to go down at once when problems occurred with any of the
few analyzers that were installed.
The Solution
An inline fluoride ion
selective sensor, specially engineered to water and wastewater application
was chosen, with a rugged fluoride mono-crystal ion sensing element, and a virtually
maintenance solid state reference system. In order to optimize the stability
of the inline fluoride sensor measurement, a low flow sample bypass system
was employed. A menu driven, simple to use, industrial ion selective
transmitter and analyzer that was capable of calibrating, displaying,
outputting and controlling in ppm units was selected. A convenient bayonet
style twist lock inline installation style was selected for its ease of
removal, facilitating the required calibration and cleaning. Calibration
solutions were formulated that were ten fold (one decade) apart in value and
would bracket the target concentration range. The calibration solutions were
designed to closely mimic the expected ionic background of the measured
solution. The calibration system simplified the validation of the online
fluoride analysis system and reduced the need for grab sample calibration all
while replacing the cumbersome sampling fluoride analyzer.
The Fluoride Sensor Used:
Model: AB 8100-100-10 Fluoride Ion Selective Sensor
Description: 1” MNPT Twist Lock (Quick Disconnect) ULTEM Bodied Fluoride
Ion Selective Sensor; Integrated 100 Ohm Platinum Temperature Element; 10
feet cable to connect directly to Rosemount 54e-ISE
Analyzer/Transmitter/Controller
Choosing the Correct pH/ORP/ISE Sensor
1.
Choose a sensor body type that
suits the physical parameters of the
installation (refer to the Configurations
Portion of pH/ORP and Ion Selective webpages).
2. Choose
a sensor that suits the process application, temperature,
chemistry, and physical
parameters of the installation (refer to Sensor Selection Guides
and call factory or local sales agent for support)
3. Choose a sensor housing material that is compatible
with the process chemistry, temperature & pressure (refer
to Chemical Resistance Charts as posted under the Technical
Documents portion of the website).
4.
Select suitable temperature compensation element, solution
ground & integrated preamplifier based upon the mating pH/ORP Instrument (refer to Electrochemical Instrumentation
Page & ask for factory support).
5.
Specify the required
cable length based
upon installation
location (refer
to Part Numbering Guide).
*
Subject to application qualification and review by an approved ASTI sales
agent and/or factory. Performance guarantee is posted on the ASTI online
application questionnaire page.
**
See list of supported pH/ORP/ISE Instruments webpages as posted on the ASTI website.
***
Completion of Application Questionnaire form is required. Other restrictions
may apply.
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