Transcript PowerPoint-Präsentation

4690 Turbidity Systems
Accurate, reliable turbidity measurement
© ABB Group
April 13, 2015 | Slide 1
ABB’s Range of Turbidity Sensing Systems
In-line flow-through and in-situ dip sensors
4690 Range

A range of flow-through turbidity
systems available with optional autocleaning for reduced maintenance

EPA180.1 & ISO 7027 compliant
designs based on light scatter
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Ranges available to measure up to
400 NTU
4670 Range

A range of flow-through and in-situ dip
sensors with auto-cleaning for
reduced maintenance

Measures light absorption to calculate
turbidity value

Ranges available to measure up to
2000 FTU
All systems available with dry secondary
calibration standards for reduced cost of
ownership
© ABB Group
April 13, 2015 | Slide 2
4690 Turbidity Range
For the measurement of turbidity in drinking water
© ABB Group
April 13, 2015 | Slide 3

Turbidity is a critical measurement in
drinking water -indicates water quality
and filtration effectiveness

ABB’s 4690 range of turbidity systems
offer reliable, accurate turbidity
measurement with low cost of
ownership

Suitable for turbidity measurement
throughout the drinking water plant
Accurate, Reliable Turbidity Measurement
Throughout the drinking water plant
1. Raw Water/Source Monitoring
Provides an indication of the solids
loading entering the treatment plant to
enable adjustment of the coagulant
dose.
2. Monitoring clarified water
Clarifier supernatant turbidity
measurement monitors clarifier
efficiency to provide early warning of
floc blanket break-up or incorrect
coagulant dosing.
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3. Filter backwashing control
Monitors filter backwash curve to minimize
clean water usage.
4. Monitoring of filtered water
Ensures correct operation of the filters and
guards against turbidity breakthrough.
5. Monitoring of final drinking water quality
Provides a final quality check after
disinfection before distribution.
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© ABB Group
April 13, 2015 | Slide 4
5

The 4690 range of turbidity sensors
utilize a nephelometric design
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Light passes through the sample
where it is scattered by any
suspended particles

such as silt, clay, algae, organic matter,
microorganisms, colloidal material, and
large dissolved molecules

This scattered light is measured by a
detector that is located at a 90° angle
to the incident beam

Detector response correlates to
turbidity
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
Light
Principle of Operation
Nephelometric measurement
A higher level of scattered light
reaching the detector results in a higher
turbidity value
Ultralow back-scatter allows for very
accurate readings as only light
scattering due to turbidity is measured
Light is scattered by suspended
particles in the water
Detector
Lens
Light
Source
Lens
Scattered light is measured at a 90°
angle to the incident beam
© ABB Group
April 13, 2015 | Slide 5
Choice of Both ISO and EPA Compliant Sensors
Suitable for regulatory monitoring
1
United States Environmental
Protection Agency
2
International Organization for
Standardization
EPA1 Compliant Sensor

EPA 180.1 compliant sensor uses a
“White Light”
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White light sensor is good for low level
turbidity measurement
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Suitable for US EPA reporting of
filtered water
ISO2 Compliant Sensor
© ABB Group
April 13, 2015 | Slide 6

ISO 7027 compliant sensor uses a
“Near Infrared LED”
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The wavelength (860-890nm) is less
susceptible to color interferences

Good for both low level turbidity
measurement and for measuring
samples with color
4690 Turbidity Systems
Product overview
Wall- or panel-mounted transmitters available
Easy-to-use, ultra-stable electronics with in-built digital
filters for bubble rejection
Auto-clean system
Programmable automatic cleaning reduces
maintenance and ensures sensor accuracy and
reliability
Dry Standard Standards
Simplifies routine instrument verification, eliminates
chemical standard preparation errors and reduces cost
of ownership
Sample Flow Cell
Flow-through nephelometric design with minimal
sample residence time provides fast response to
turbidity changes for improved process control
Emitter & Receiver Assemblies
EPA180.1 or ISO 7027 Compliant design
Integral Sample Feed & Drain Valves
Provides simple installation and quick and easy calibration
© ABB Group
April 13, 2015 | Slide 7
Flow-Through Sensor Design
Fast response and reduced maintenance
Fast Response Time

Minimal sample residence time allows
fast response time to process
changes
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Typically 90% step change in <45
seconds
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Up to 75% faster response time than
some competitor turbidity designs
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Offers improved process control
Reduced Maintenance
© ABB Group
April 13, 2015 | Slide 8
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Flow-through design does not act as a
“sediment trap”
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Removes requirement for manual
cleaning of settled particles in the
sensor body
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Reduces cost of ownership
Automatic Cleaning of Optical Cell
Reduces maintenance and ensures accuracy
© ABB Group
April 13, 2015 | Slide 9

Optical cell fouling greatly reduces
accuracy of turbidity measurement
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ABB’s 4690 Sensors feature an Autoclean system that overcomes the
problem of optical cell fouling

Mechanical wiper assembly physically
wipes clean the optical cell at userprogrammable intervals

No need to regularly disassemble the
sensor to inspect/manually clean the
photocell window

Reduces maintenance and lowers
cost of ownership whilst ensuring
accuracy and reliability
Dry Secondary Calibration Standard
Simplifies routine instrument verification

Optomechanical filter that diverts a
fixed quantity of light to the detector
corresponding to a known turbidity
value
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Each secondary standard is factory
calibrated and certified against a
primary formazine standard

Quick & simple verification/calibration
procedure that minimizes instrument
downtime

Reduces cost of ownership by
reducing chemical standards and the
time taken on-site to prepare such
standards

Minimise employee’s exposure to
Formazine which is highly toxic and a
suspected carcinogen

Simple to use, repeatable and reliable
Available in different turbidity
concentrations to suit the application
Insert directly into sensor body
during calibration procedure
© ABB Group
April 13, 2015 | Slide 10
Patented User Replacement Bulb Design
Allows lamp replacement in under a minute
© ABB Group
April 13, 2015 | Slide 11
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Changing incandescent bulbs to
ensure peak performance used to be
a laborious process
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With ABB’s replacement bulb design
you can throw those cotton gloves
away!

Each bulb is supplied fully protected in
a patented assembly with integral light
guide
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No direct contact with the bulb

Ensures maximum lamp life
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No threading of wiring
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No waiting for the bulb to cool
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Simply plug and play
Low Maintenance
Minimises cost of ownership
Task
Recommended frequency
Visual check - check sample flow, check for any leaks
Weekly
Calibration verification1 with secondary standard2
Monthly
Calibration2 with primary standard4 – as per regulatory
guidelines
Quarterly*
Wiper blade replacement
Quarterly
“White Light” source (EPA 180.1) replacement
Annually
“Infrared” LED source (ISO 7027) replacement
Every 5 years
1Calibration
verification means a procedure used to check whether or not the calibration of the instrument is within certain limits
2Secondary
standard means a standard that the manufacturer has certified will give instrument calibration results equivalent to the
results obtained when the instrument is calibrated with primary standard such as formazin
3Calibration
means a procedure which checks or adjusts an instruments accuracy by comparison with a defined standard or
reference
4Primary
standard means a standard, such as formazin, used to calibrate the instrument response with respect to analyte
concentration
*Based on EPA guidelines for individual filter effluent
All service tasks can be quickly and easily performed on site without the
need for a skilled technician
© ABB Group
April 13, 2015 | Slide 12
4690 Turbidity Systems
Accurate, reliable turbidity measurement
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© ABB Group
April 13, 2015 | Slide 13
Flow-through turbidity design

Fast response to process turbidity
changes due to minimal sample
residence time

Choice of EPA or ISO compliant
methods
Automatic sensor cleaning
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Reduces maintenance requirements

Optimises performance sensitivity
Dry secondary calibration standard

Accurate, repeatable, simple, safe

Realise significant cost savings by
reducing the use of primary standards
Simple to use and maintain
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Intuitive, user-friendly design
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Simple-to-perform annual service
Reliable and accurate measurement

Ultralow back scatter for accurate
measurement of low turbidity values
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Automatic bubble rejection to
compensate for erroneous readings
due to degassing
© ABB Group
April 13, 2015 | Slide 14