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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. 16 –
Sugar Refining (Extraction)
from Cane Sugar Syrup
High Temperature
Evaporation and Boiling Processes for pure sugar recrystallization
High and Ultra High Temperature
Resistant inline process pH sensors
Excellent accuracy over repeated
temperature cycling from batch process
Specially engineered custom high
temperature conductive polymer reference
Minimum cleaning and calibration
through non-porous solid state reference technology and rugged thick-wall hemispherical
hysteresis resistant pH glass
The Problem
A
sugar refining company in Venezuela wanted to reduce the cleaning and recalibration frequency
for their high temperature pH control system in their evaporation and boiling
sugar refining processes. The frequent sensor deaths slowed down the
production process efficiency due to the replacement sensor installation time.
Milk of lime Ca(OH)2 is added at various stages of the process
to optimize yield and minimize energy consumption in the refining process, making
pH control a critical factor to plant efficiency. The previously used sensors
functioned properly for only short periods of time before the high
temperature conditions and deposits from various calcium derivatives and viscous
sugar syrup necessitated an aggressive chemical and mechanical cleaning,
followed by a time consuming recalibration to ensure that the online pH
sensor would provide an accurate reading. A lower maintenance alternative
was required.
The Solution
The combination of a rugged
thick wall break and crack resistant high temperature MUGG pH glass sensing element
and a specially engineered ultra high temperature resistant non-porous
conductive polymer reference system. Because the expansion coefficients of
the plastics and other components are well matched with the solid state components
employed, temperature cycling does not result in sensor failure.
A temperature compensation
element was embedded in the sensor (compatible with the existing pH analyzer)
in a sealed design that avoids temperature compensator failure during
operation (a common mode of failure for many pH sensors). A high impedance
CMOS operational amplifier (preamplifier) converts the high impedance pH
signal input to low impedance mV output. Such a preamplifier can be readily
embedded for most transmitters (compatible with the existing pH meter)
ensuring optimum signal isolation from the surrounding equipment. The result
was greatly lowered maintenance frequency and sensor failure, resulting in
greater product yield and reduced operating costs.
The pH Sensors Used:
Model: PN 6131-1000-10 pH Sensor for Mettler Toledo 2100e
Analyzers
Description: ¾”- 1” MNPT Immersion ULTEM Bodied High Temperature
Resistant pH Sensor with integrated 1000 Ohm Platinum Temperature Element; 10
feet cable to connect directly to Metter-Toledo Transmitters (See Hook-Up
Schematic for Details)
Rated for continuous
inline use up to 135 degrees Celsius at 100 psi
Model: PN 6241-100-10 pH Sensor for Endress+Hauser
Analyzers
Description: ¾”- 1” MNPT Immersion PEEK Bodied Ultra High
Temperature Resistant pH Sensor with integrated 100 Ohm Platinum Temperature
Element; 10 feet cable to connect directly to Foxboro Endress+Hauser pH
Analyzer/Transmitter (See Hook-Up Schematic for Details)
Rated for continuous
inline use up to 150 degrees Celsius at 150 psi
Choosing the Correct pH/ORP
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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