representative sampling by chuck abbott. automatic samplers
TRANSCRIPT
Representative SamplingBy
Chuck Abbott
Automatic Samplers
Industry Sampler NeedsIf sampler required, usually going to be
refrigeratedPermit determines type of sampling needed and
frequencySequential sampling in multiple bottlesComposite samples
Permit determines if any additional monitoring is neededFlow pacing for flow proportional samplespH monitoring and ability to enable sampler to
take sample on high or low pH event
Sequential Sampling Usually done when
monitoring for specific events like slugs.
Used by enforcement to check industry and determine pollutant trending
Multiple bottles are used with the standard being the 24 bottle sampler.
One or more samples collected in individual bottle each hour.
flexible enough to take samples/bottle or multiple bottles/sample
Pro Pak•Alternative to polypro bottles. •Designed to reduce bottle cleaning cost•Disposable•Sequential bags or composite bag
•Directly replaces Polypro Bottles
Pre-treatment Trends
Pre-treatment groups are moving towards Portable Refrigerated Samplers as well as compact units such as the GLS
Pre-Treatment group monitoring needs.Usually portable samplersNormally use composite but have
applications that call for multibottleNeed flexible program capabilities
May need 2 part program Flow proportional sampling Sample enabled/ triggers based on events
Stored Data
Data can be stored in either 2105 or 6712 internal data logger
•Data Collected via Flowlink 5.1
Important features for Industrial pre-treatment useAccurate and repeatable volume deliverMultiple bottle capabilitiesAccurate liquid detection systemAble to take samples based on flow input or
based on time or a combination of imputsAble to store sample, flow and other data that
can be retrieved laterEasy to maintain
Bottle Options
Sample Size and FrequencyMinimum sample volume
collected with an automatic sampler should be no less than 10 ml.
Recommended size is no less than 50 ml because of liquid detector Sample volume
repeatability Volume required by lab Bigger is better theory
Preventative SamplerMaintenancePump tubing replacementSuction line replacementContainer replacementDiagnostic routinesVolume calibration
Pump CounterCounts actual revolutionsDetermines pump time
not related to timenot affected by battery
Specifiable Feature!
6712 Pump TubingBands indicate position
bands won’t slipLabel for pump
shows installation, direction
0.29”0.25”
Tubing Life IndicatorSet for 1,000,000 countsAdjustable
site conditionsMaintenance tool
Industrial MonitoringIntegral monitoring of flow, level, pH,
temperature and SDI-12 parametersDiscreet bottle samplingFlexibility in programming
2 part programmingNon-uniform time/ random time intervalsTime enables
Volume DeliveryLD90 and pump counterMost accurate volumes
prevents biasing in samplesprevents overflows
+/- 5 ml repeatability
Types of SamplesDistribution
Composite Single Bottle
Sequential Multiple Bottles
Samples Per Bottle Bottles Per Sample
PacingTimeFlowEvent
Types of SamplesComposite
Composite samples are small volumes of sample taken over time and placed in a large container.
Composite samples can be taken in two ways, fixed volume or flow proportional
Composite
1
2
3
4
5
Sequential Sampling Usually done when monitoring
for specific events like slugs. Used by enforcement to check
industry and determine pollutant trending
Multiple bottles are used with the standard being the 24 bottle sampler.
One or more samples collected in individual bottle each hour.
flexible enough to take samples/bottle or multiple bottles/sample
Sequential Sampling
1 2 3 4 5 6
Two Part Programming
1 2 3 4 5 6
2
1
4
3
6
5
8
7
Part A Part B
1 2 3 4 5 6 10987 11-24
Sampler PacingTime
Uniform Time- Fixed Volume Uniform Time- Volume Dependent Uniform- Flow Dependent Volume Non Uniform Time Random Time
Flow Flow Paced – Time Override
Trigger and Event Pacing
Challenging sampling application accessoriesDifficult to reach locationsSampling from Pressurized linesSampling from Flumes and WeirsSampling in low flow conditionsBatch Dischargers and how to get a
representative sample.
Best Sampler LocationAccessibility
Close to source Conserve power Maintain line velocity Reduce wear Protect suction line Minimize lift
Max lift- 8.5m/28ft Auxiliary pump
Safety of PersonnelSecurity Availability of Power SourceGood mixing for representative
samples
How to get best representative sampleUse proper strainer
size and typeKeep intake tube short
and as vertical as you can
Keep sampler close to sampling point
Change Pump Tubing when needed.
Change intake tubing often and keep clean
Strainer Placement -Flumes
Strainer Placement - WeirsStrainer location here is not going to enable a representative sample to be taken.
Isco Flow Thru ChamberFlow-thru chambers are available for use in low pressure (under 30 PSI) closed pipe applications.
Suction Line RequirementsSimilar to strainerfollow most stringent requirementif glass needed, use Teflon suction lineclean and/or replace as needed
Pressurized Line SamplingTeledyne Isco now offers pressurized sampling systems to allow sample collect from pressure lines less than 300 psi.
Spa Products
Specially developed products to help meet you sampling needs:
•Black Vinyl Suction line
•Ultra Low flow strainer
•Customer support hangers such as the Pro Hanger•Remote pump option
Low Flowing PipesLow Flow Strainer
1/4” to 3/8”¼” suction line
Batch discharging and representative samplingWhen taking a sample
from any source it must be representative of the source.
Sampling a batch discharger best done with flow proportional sampling method
Liquid level indicator or trigger based on level or rate of change
Batch discharge example with flow paced sampling when triggered by level increase
AlarmingBoth discreet and digital alarms available
•SPA 697 for contact closure•SPA 1489 CDMA Modem
•SMS Alarms
Remote Communication
Remote Communication through 2105 C Module as well as SPA 1489 CDMA Modem
Any Questions?