Sampling Rev F Feb 2011

7/30/2019 Sampling Rev F Feb 2011

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sampling



sampling solutions

engineeredrepresentative

samplingsystems



principles of sampler design

All particles must have an equalchance of being sampled

No loss or contamination of thesample

Sample cutter must move at aconstant speed

Cutter blades must be sharp andstraight

Cutter must have sufficient capacityto hold the sample

Cutter opening must be constant



linear cross stream sampler drives

< ball screw

belt drive >

samplers using chain, pneumaticor hydraulic drives always haveissues associated with potential

‘elasticity’ of oil and air and thehigh wear of chains



typical ball screw sampler BSLS40

The installation of the

falling stream linearsampler at thedischarge end of abelt conveyor is theinternationallypreferred method of

sampling the conveyor



ball screw linear sampler advantages

constant drive speed

electric power

rapid acceleration /deceleration

minimal maintenance



ball screw linear cross stream sampler

Primary, secondary or

tertiary samplingapplications

Feed rate: <500 TPH

Max. belt width: 700mm

Also suitable

for slurrysampling

Model BSLS 25-1000



ball screw linear cross stream sampler

Model BSLS 40-1800

Primary or secondarysampling applications

Feed rate: <3,000 TPH

Max. belt width: 1,400mm

Also suitablefor slurrysampling



belt drive linear cross stream sampler

Model BDLS 80-3500

Feed rate: 7,000-

16,000 TPH

Max. belt width:2,500mm

Primary samplingapplications



synchronous belt drive linear cross

stream sampler

Model SBD 3700

Primary samplingapplications

Feed rate: 7,000-16,000 TPH

Max. belt width:

2,000 mm



vezin sampler

rotary cross streamsampler forprimary,

secondary ortertiary samplingfrom a falling

stream of slurry orfree flowing solids



vezin sampler

mainproduct

flow

sample

rotatingcutter



rotary sample collector (RSC)

an indexing carouselfor the automaticcollection and securestorage of samples

each sample

container isautomatically sealedfrom contaminationand moisture loss

ergonomic design androbust construction



designing sampling systems

what do we need to help design a system for aclient?

material conveyor rate (TPH)

maximum particle size

sample requirements number cuts per hour/ tons sample period/ length of shift

desired sample mass at end of period

conveyor details belt width sampler location



fines

6 mm

lump

31.5 mm

typical ship

loading

sampling

systemflowchart

primary sampler

hopper

feeder

secondary

sampler

reversible feederdiverter

hopper

feeder

tertiary

sampler

physical sample chemical sample

primary

crusher

BSLS 50/2300 flow rate = 3000 tph cutter aperture = 150 mm primary sample size = 260 kg/cut min. requirement = 1 cut/12 min.

BSLS 40/1300 feed over 5 min. effective flow rate = 3.1 tph cutter aperture = 150 mm secondary sample size = 269 g/cut take 20 cuts = 5.38 kg

Wescone 300 product = 80% < 6 mm crush time = 30 sec.

Vezin 300/2/10 1 x 10% cutter = 504 g sample

RSC 4/20

collect hourly 6.04 kg chemicalsamples= 337 kg total sample



typical sampling station design



Iron ore ship loading sampling

Rio Tinto, Australia



Iron ore receiving port sampling

CIQ, China



Steel plant sampling

ThyssenKrupp, Brasil

retrofit cross stream samplers to systemoriginally designed to accommodatecross belt samplers



sampling slurries

the basic principle of sampling isthat all particles should have equalopportunity of being sampled

for slurries in pipes a complete cutof the stream must be made toavoid variations within the pipe

this cut can be made directly in thepipe or at a launder discharge



pipe sampler for gravity fed slurries

slurry entry

slurry exitsample

rubberlining

samplecutter



dual slurry

sampler

mainproductflow

primarysample

secondary

sample

primary cutter

sample agitator

secondary cutter

metering valve

cutter wash downsprays

cutter washdown sprays



slurry “extractors”

poppet valve samplers can onlybe considered as “extractors” and

the sample should only be usedfor internal process control, neverfor metallurgical balance



pipe sampler for pressure fed

slurriesslurry entry

mixer

sample

pneumatic actuator



considerations when sampling slurries

allow sufficient vertical pipe height toinstall samplers... even if later

understand the value of the head,

concentrate and tails sample...only these can give you a truemetal balance.

use “extractors” and online analysisto maintain plant control but not todefine performance

i b fit f li



46% Mn= $345/tonne

acceptable limit at46% Mn is +/- 1%

supplier can deliver product at 45.5 – 46.5%

without penalty supplier intended to supply 45.5% butactually supplied 46.5% = loss $7.50 per tonne 40,000 tonne shipment = $300,000 loss

50 shipments/year = $15 million/year risk

economic benefits of sampling

… manganese case study

sell price = $7.50/1% Mn per tonne



how easy is it for such a loss to occur?

2 tonne composite sample is takenduring vessel loading

1 x 70 mm particle = 140 g =

0.00007 of the composite sample average grade of large

particle = 0.5% higher

than the average for theentire stream of ore

what happens if a single large particle

fails to enter the sample cutter?



1 x single particle failing to enter thecutter would cause a bias of the gradedifference (0.5% Mn) x proportion by

which large particles were underrepresented:

0.5% Mn x 0.00007 = 0.000035% Mn

therefore, to end up with a 0.1% loss of Mn you only need 0.1/0.000035 = 2850particles or 400 kg of material lostduring sampling




since lost material

simply rejoins theproduct stream youwould never know

about it!




laboratory sampling

1. Scoop Sampling 21.0%

2. Cone & Quartering 19.2%

3. Table Sampling 7.0%

4. Riffle Splitting 3.7%

5. Rotary Sample Dividing 0.9%

I n c r e a s

i n g

a c c u r a

c y

estimated maximumsample error *

* based on a sugar-sand mixture



manual samplers

Riffle Splitters

Mild and stainlesssteel

Laboratory unit

Field unit (multi

tiered)

Sampling Probes

Hand Slurry Samplers



rotary sample dividers

segmental bucket typefor the accurate division of bulklaboratory samples into multiplerepresentative samples

5 L

1600 L




bulk batch sampling andblending systems




residue typeFor the accurate and representativedivision of a specific portion of bulklaboratory samples into a retained

sample while allowing the residue topass to reject



www.essa.com.au

[email protected]

ASX code: ESS

The information contained in this document isprovided for promotional purposes. Essa does notwarrant its accuracy or completeness.While Essa attempts to ensure that the informationis accurate, Essa reserves the right to changefeatures or specifications at any time. Performancecharacteristics will vary depending on the

application. Please check with Essa at the time of

Sampling Rev F Feb 2011

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