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Features
·
Guaranteed Longest Lasting
Sensors Available with performance guarantee *
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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. 18
Measurement of Ammonia in Municipal Drinking Water
for sterilization with Monochloramines
Real-time continuous online
measurement system for ammonia
Low Initial
Procurement Cost compared to competing technologies and offerings
No need for
chemical feed and rebuilding of sensors
Lower Cost of Ownership
due to very long sensor lifetime, low maintenance & cleaning requirements
for inline, immersion & submersion ion selective sensors
Intuitive and
easy to use Rosemount 1056 and 1057 analyzer programmed and configured for
ammonia and nitrate ion selective analysis
All new systems
come preconfigured, precalibrated and fully qualified to install, plug-in and
immediately place into service especially for
compliance purposes
Only periodic
1-point grab sample offsetting is required – this “Standardize” calibration
can be performed WITHOUT removing sensor from service!
The Problem
A number of municipal drinking
water plants wish to carefully control their level of free ammonia (often
also described as total nitrogen of NH3-N) and chloramine (also called
monochloarmine or MCL) used to ensure that the water remains suitable for
human consumption. Until now, the
technologies to measure the two species of interest for this application
(free ammonia and chloramine) have been only possible with expensive sampling
analyzers that required reagents, and significant operator involvement to
ensure nominal operation. The result
has been the operator and time intensive method of periodic grab sampling to
ensure the sterilization system is working within the appropriate limits
(typically 0.1 to 0.6 ppm for free ammonia for example) continues to be used
at most facilities. The high cost of
such sampling analyzers and the process of grab sampling can often mean that not as much information about the
process is available as would be desired for control and monitoring
purposes. The labor demands or grab
sampling can be particularly problematic with smaller and remote facilities
that have less frequent operator presence due to personnel limitations. In some conditions, the pH and temperature
can fluctuate throughout the year, meaning that the percent of ammonia
(NH3-N) that will be in the measurable ionized ammonium form can vary.
The Solution
In cases where monochloramine and pH are already measured, a single
or dual channel ammonium analyzer is employed to monitor the free (residual)
ammonia levels. In cases where no
monochloramine measurement is
performed, the monochloramine and free ammonia measurement can be combined
into one dual channel analyzer to perform both measurements. For some installations a triple channel
configuration of ammonia, ammonia and pH is the most cost effective option
although other combinations are possible as well. The ability to measure in particular
ammonia online in real time with minimal calibration and cleaning
requirements makes it possible to record and control the process between grab
samples, while the low up-front commissioning costs and low residual cost of
ownership in terms of sensors and maintenance makes it possible to measure at
more points of interest without exceeding budgetary restrictions. Since the conversion of dissolved ammonia
gas to the ammonium ionized form in solution is a pH and temperature
dependent process, ASTI offers the ability for this pH and temperature
compensation to be performed in real-time as well to yield information about
the total amount of free ammonia that is present (see graph below for details
about this phenomenon). The graph
shows that ammonium is the dominant form of free ammonia under most pH and
temperature conditions common for municipal drink water facilities.
The online ammonium ion
selective measurement system can be calibrated for 1-point offset without
removing it from service, making it ideal for low maintenance continuous
use. The online ion selective
measurement systems for ammonia can readily be referenced to most any grab
sampling laboratory or portable method (including the popular colorimetric
kits and existing sampling analyzers).
Two-point calibrations need only be performed for new sensors in most
cases once again minimizing the service needs. These online ISE systems are available for
a wide variety of installation styles and can be integrated into any modern
PLC and DCS systems.
Sensors are available in a
wide variety of options including preamplifiers to support long cable lengths
up to 300 feet and fully submersible assemblies to interface with any
existing process connections and configurations. In addition, popular twist lock quick
disconnect inline styles are also supported for easy of removal for periodic
cleaning should it be required as are “plumb-and-play” low-flow panel that
minimize installation time and labor.
Sensors Used for Measurement
Sensors for in Tank Installations
with Standpipe for Immersion or Submersion (with waterproofing option) – 3/4”-
1” MNPT Immersion Sensor Body Configurations
Model: AB 6410-1000-10-TL Ammonium Ion Selective Sensor
Description: Ammonium Ion Selective Sensor with 1000 Ohm
Platinum Temperature Compensation Element; 10 feet cable to connect directly
to 1056 or 1056 ISE Analyzers
Model: PNZ 6052-1000-10-TL pH Sensor
Description: Industrial pH Sensor with 1000 Ohm Platinum
Temperature Compensation Element; 10 feet cable to connect directly to 1056
or 1056 ISE Analyzers
Sensors for Inline Installations
with Quick Disconnect Bayonet Style Fittings
- 1”
MNPT Twist Lock Quick Disconnect Sensor Body Configurations
Model: AB 8410-1000-10-TL Ammonium Ion Selective Sensor
Description: Ammonium Ion Selective Sensor with 1000 Ohm
Platinum Temperature Compensation Element; 10 feet cable to connect directly
to 1056 or 1056 ISE Analyzers
Model: PNZ 8052-1000-10-TL pH Sensor
Description: Industrial pH Sensor with 1000 Ohm Platinum
Temperature Compensation Element; 10 feet cable to connect directly to 1056
or 1056 ISE Analyzers
Analyzers Used for Measurement
Model: 1056-XX-22ISE-32-YY (Ammonium / pH)
Description: Dual Channel Ammonium & pH Analyzer, Transmitter and
Controller
Model: 1057-XX-22ISED-32ISE-42 (Ammonium / Ammonium
/ pH)
Description: Triple Channel Ammonium, pH and Nitrate Analyzer,
Transmitter and Controller
XX is the power supply option and YY is
the output option (for 1057 only 4 each 4-20 mA output is available). ISE configuration must be specified at time
of order. Complete ISE systems only
available directly from ASTI as complete online measurement systems.
Ion selective sensors are NOT available for sale without ISE analyzer
as provided by ASTI. Application must be validated by ASTI factory prior to
sale. References are available upon
request.
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