mark ledger md agua africa mark titus product manager hach
TRANSCRIPT
Mark LedgerMD Agua Africa
Mark TitusProduct Manager HACH
Original Equipment Manufacturer
Custom Design and Fabrication
Full Spectrum of FiltrationSingle Media, Dual Media
Cartridge Filtration, Bag Filtration
Decolourisation, Ion Exchange, DI
Iron Removal
Ultrafiltration
Nanofiltration
Reverse Osmosis
Disinfection
Process Chemicals
Marine Engineering
®
Biotechnology and Bio Engineering
Custom Bio Augmentation programs
Selective Bacterial / Enzyme solutions
Powders, Solids & Liquid formulations:
Industrial / Institutional
Agriculture
Waste Water Treatment
Environmental Bio – Remediation
Aqua Culture
HTH Scientific – Industrial, Municipal & Commercial
Products IndustrialHTH Chips Aquaculture Beverage
Granular Chlorine Breweries Dairy
Stabalised Chlorine Tablets Canneries Meat Process
Chlorine Tablets Vinyards Orchards
Algaecides Paper & Pulp Poultry
Metal Removers Tanneries Vegetables
Commercial MunicipalClinical Pools and Tanks Industrial Water
Miscellaneous Potable Water
Restaurant Private Water
In Line Feeder Systems
Reservoir Chlorination System
HTH Controller Units, On line Control & Dosing
On line chlorine monitoring and control
Automated dosing systems
Cal Hypo chips, TCIA, HTH granules
Reservoir treatment scientific floaters
HACH Scientific Analytical Laboratory Equipment
Laboratory Chemicals,Reagents and MediaAll parameters ( Acidity – Zinc )
Fine chemicals and Supplementary Reagents
Single Parameter Test Kits
Multi Parameter Test Kits
Test Kit Replacement Parts & Reagent re orders
Microbiological Laboratory supplies
Laboratory and Field instrumentsMeters and Probes
Spectrophotometers and Colorimiters
Sample Cells
Laboratory and Portable Turbidity Meters
General Laboratory Equipment SuppliesA – Z of laboratory requirements
Linkages & Considerations……
• No plant can be designed to be effective without correct analytical information
• No plant can be operated correctly without accurate analytical information
• No process can be properly managed without correct analytical information
• Environmental impact cannot be evaluated without correct analytical information
• Effective chemical treatment programs cannot be managed and assessed without accurate analytical information.
• Key is…… understanding and following the correct methodology, process selection, procedures, interpretation and management of your results and information.
Application and desired quality of analysis
LDO – Luminescent Dissolved Oxygen
HACH IntelliCAL Probes
• Why measure DO ?• Applications / Where ?• Considerations / Factors• Technology / Uniqueness• How ?• Benefits / Advantages
What is Dissolved Oxygen?
• Dissolved oxygen (DO) is simply a measurement of the amount of oxygen gas dissolved in water.
O2
O2
O2
Why Measure Dissolved Oxygen?
• Important indicator of water quality
• Related to:– Water pollution– Water treatment processes– Chemistry of metals– Biological activity
Where is DO Measured?
• DO Monitoring Points:– Equalization
Basin
– Aeration Basin
– Nitrification Basin
– Aerobic/Anaerobic Digester
– Plant Effluent
EqualizationBasin
PrimaryClarifier
Aerobic / AnaerobicSludge Digester
Gravity SludgeThickener
SecondaryClarifier
NitrificationBasinAeration Basin
Plant Inlet(Influent)
FinalFiltration
Disinfection
Plant Effluent
Return Activated Sludge (RAS)
Waste Activated Sludge (WAS)
SludgeDewatering
SludgeDisposalSludge
Disposal
Centrate
1
1
1
1111 1
Why is DO Measured?
• Wastewater collection – H2S control– Aeration control – i.e. Compressors– Chemical control – i.e. Hydrogen peroxide
• Equalization basin & Raw junction chamber– Odor control– Pre-aeration to reduce BOD loading– Sudden DO drop may indicate industrial discharge
Why is DO Measured…?
• Aeration basin– Maintain adequate DO level for aerobic organisms,
yet low enough DO to conserve energy!
• Oxidation ditch– Maintain rotor depth and speed
• Sequencing batch reactor– Use DO levels, rather than time, to control process
Where is DO Measured?
• Trickling filter/RBC effluent channel– Measure effluent channel DO to ensure low recycle
rates while maintaining adequate aeration– Ensure proper aeration exists from zoogleal slime
development
• Biological nutrient removal process– Nitrification process maintains DO between 2 - 3 mg/L– Anoxic zone DO < 0.5 mg/L– Anaerobic zone DO < 0.2 mg/L
Where is DO Measured…?
• Final effluent channel– Ensure plant effluent meets
discharge/permit /legislative requirements
• Up and downstream from plant effluent– Ensure effluent does not damage receiving
waters
Factors Affecting DO
DO Saturation tables provide DO saturation concentration
based on temperature and pressure
Factors Affecting DO
DO Solubility as a function of temperature and salinity
DO Meter intelliCAL
• DO meter and probe are used to measure dissolved oxygen concentration electrochemically.
DO Meter Advantages
• Ease of use
• Limits exposure to chemicals
• Safe disposal of samples
• Fast
• Accurate measurement in colored samples or samples containing suspended solids
The Hach LDO™ Sensor :
Thermistor
Blue LED
Red LED
Photo diode
Luminescent Dissolved Oxygen
How Does HachLDO™ Work?
• A sensor is coated with a luminescent material.
• Blue light from an LED strikes the luminescent chemical on the sensor.
• The luminescent chemical instantly becomes excited.
LEDPhoto Diode
Probe
Sensor
LED
0,0
0,2
0,4
0,6
0,8
1,0
1,2
0 10 20 30 40 50 60 70 80 90 100
Zeit [us]
Normierte IntensitätExcitation Pulse
How does HachLDO™ work ?
LDO™ Sensor
Sensorcap
LEDPhoto Diode
Sensor
LED
How Does HachLDO™ Work?
• As the excited chemical relaxes, it releases red light.
• The red light is detected by a photo diode.
• The time it takes for the chemical to return to a relaxed state is measured
LEDPhoto Diode
Probe
Sensor
LED
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0 10 20 30 40 50 60 70 80 90 100
Time [us]
Normierte Intensität
1without O2
Emission Profile
Excitation Pulse
How Does HachLDO™ Work?
LDO™ Sensor
Sensorcap
LEDPhoto Diode
Sensor
LED
How Does HachLDO™ Work?
• When oxygen contacts the luminescent chemical, the intensity of the red light decreases
• The amount of time it takes for the material to relax is reduced
LEDPhoto Diode
Probe
Sensor
LED
Oxygen
LuminescentIndicator
Molecules Gas PermeablePolymer Matrix
Clear, GasImpermeable
Substrate
0,0
0,2
0,4
0,6
0,8
1,0
1,2
0 10 20 30 40 50 60 70 80 90 100
Time [us]
Intensity (normed)
1
without O2
Emission profile
Excitation
Pulse
2with O2
How Does HachLDO™ Work?
LDO™ Sensor
Sensorcap
LEDPhoto Diode
Sensor
LED
Oxygen
How Does HachLDO™ Work?
• The higher the oxygen concentration, the less red light that is given off by the sensor.
Oxygen Concentration
Red Emission Light
How Does HachLDO™ Work?
• The intensity of the red light is not what’s being measured.
• What’s being measured is the time it takes after excitation for red light to be given off. – Lifetime of
luminescence
LEDPhoto Diode
Probe
Sensor
LED
How Does HachLDO™ Work?
• A red LED is also present in the probe.
• Between flashes of the blue LED, a red LED of known intensity, is flashed on the sensor.
• The red LED acts as an internal standard (or reference) for a comparison to the red light given off by the luminescent chemical.
LEDPhoto Diode
Probe
Sensor
LED
Advantages of LDO
• Reduced Maintenance– No membrane to replace
• No more stretching of Teflon and worrying about air bubbles
– No electrolyte to foul or poison• No H2S poisoning of the electrolyte
• No more punctured membranes
Advantages of LDO
• Reduced Maintenance
– No anode or cathode• No cleaning of anodes• No more coating of electrodes
Advantages of LDO
• Frequent Calibration Not Required– No anode to consume and no electrolyte to
deplete means extremely stable measurements
– Internal standard with Red LED– No interference from pH swings, wastewater
chemicals, H2S, or heavy metals
Advantages of LDO
• Accurate and Stable Readings – With nothing to interfere with the readings,
HachLDO™ produces more stable measurements for a longer time
• Speed!– Turn it on and it’s running!– Response time of less than 30 seconds to 90%!
Simple Operation and Maintenance
Only one replacement partInexpensive sensor cap is simple to replace quickly
TNTplus – Auto detecting and running of analytical methods
BarcodingMultiple cell capabilityAutomatic method detectionAutoblanking240 pre programmed water analysis methods50 possible user entered calibrations
The selection criteria……application and results
What’s the benefit of correct and accurate analytical testing
and reporting?• Regulations or Permits
– Am I in compliance?
• Process control– Is my plant operating correctly?– Is it time for preventative maintenance?
• Problems and Troubleshooting– What is wrong with my system?– How can I fix it?
Thank you for your attention
Mark LedgerMD Agua Africa
Mark TitusProduct Manager HACH