reliable on-line sensing

w w w. c e m i s . f i

Risto Oikari

Director, CEMIS

17.9.2015

Reliable On-Line Sensing


CONTENTS

1. CEMIS – Centre for Measurement and InformationSystems

2. Sosio-Economic Benefits of Reliable On-line Sensing

3. Examples of on-line sensors developed at CEMIS

4. Vision for Future Sensor


CEMIS in a nutshell

CEMIS is a contract based joint

centre of University of Oulu,

University of Jyväskylä,

Technical Research Centre of

Finland VTT and Kajaani

University of Applied Sciences.

CEMIS is founded Kajaani in

2010 and employs around 110

professionals.

CEMIS specialises in research

and higher education in the field

of measurement and information

systems.

CEMIS´s mission is to provide r&d –services, training and education, new technology and innovations

for companies and research organizations developing and applying measurement and information systems.

•

•

•Oulu

Jyväskylä

Espoo

• Kajaani

Helsinki

•

•Finland


Its worth to measure: More than 2 % of the GDP is spent for measurements in developed

countries worldwide (3-4 billion euros in Finland), 80 % of global trade includes action

requiring measurements certificates, more than 50 % of EC directives contain requirements

for measurements.

Economic impact of measurements exceeds the cost many times, even several tens of times

Measurements build the better society: Reliable measurements improve competence,

efficiency and safety

Measurement is business: More than 200 measurement technology companies in Finland

(combined turnover around 2 billion euros, i.e. 1 % of GDP). 70 % of the companies are small

or medium in size (SME) (Statistics Finland 2009).

Investments in metrology research is worthwhile: Average number of new research –based

measurement technology companies per year is two (K. Kankaala et al., Sitra reports 72,

2007: 15 new research –based measurement technology companies were founded in years

2000-2006). In past few years much more thanks to Tekes TuTLI –funding!

Introduction


Why automatic on-line

monitoring is a good solution? To save money and save time (less people are needed to control process or pollution)

More real information is available for process control and for reporting (on-line monitoringgives possibility to know continuously, what is really happening)

You really know your current situation and process status, when you measure it on-line => reporting to the authorities/owners is easier => less need to explain!

Possibility to avoid environmental accidents and problems, since you can react immediately, when something happens – no long delays for reactions => Early Warning System

Possibility to adjust and optimize the process Big savings!

vs.


monitor process and pollution everywhere, where is the need (no need to worry about electricity and communication cables)

monitor even once a minute and thus you can really on-line control your process and emissions…and save money…!

Monitoring is possible all year around - heat or coldness are not making any problems (operates - 40….+80 °C)

The data is sent to automation system or to Internet wirelessly => very pleasant and fast system

Kari Ennola 2012


On-line monitoring system and wireless data transfer

Video on environmental monitoring by EHP-Tekniikka Solutions:http://www.youtube.com/watch?v=IvItLVyH_i8&feature=youtu.be

http://www.youtube.com/watch?v=IvItLVyH_i8&feature=youtu.be


Economic Value of On-line Monitoring

From EHP-Tekniikka Ltd. marketing material


Parameters to be monitored...

Measurand Lower limit Upper limit Accuracy

Level of surface water (mm) 0 250 000 0.1 %

Level of ground water (mm) 0 250 000 0.1 %

Discharge (flow) of the water (l/s) 0 > 1 000 l/s 0.1 %

Oil in water (μg/l) 0 200

pH 0 14

Conductivity (mS/m) 0 > 1 000 0.5-1 %

Redox (mV) - 2 000 + 2 000 0.5 %

Oxygen (mg/l) 0 20 0.1 mg/l

Temperature (°C) 0 80 ± 0.25 ° C

COD/TOC/DOC (mg/l) 0 > 100

NO3-N and NO2-N (mg/l) 0 1 000 0.1 %

NH4-N (mg/l) 0 1 000 0.1 %

PO4-P and NO2-N (mg/l) : analyser 0.1 25

Total P and total N (mg/l) : analyser 0.01 3 000

Suspended solids (mg/l) 1 1 000

Turbidity (NTU) 0 3 000

Toxic metals (mg/l): Cu, Ni, Zn, Pb, Cd … 0.01 1 000

Sulfates (mg/l)

Bacteria

Drugs residues, hormone-like subtances etc.

Others...Totally about 45 parameters !

Under development at CEMIS

Typical values


Need: Ability to measure simultaneously different trace metals at concentration levels down to the fractional parts per billion (sub-ppb), using inexpensive, versatile, reliable, small size instrumentation, with no requirement of special installation

Conventional electrochemical detection: Stripping voltametry based on amalgamation on a mercury electrode

Our key solution is anodic stripping voltametry by

1) Screen printed mercury electrode

2) Screen printed mercury-free electrode (based on graphene or bismuth)

3) Gold wire electrode

We have also expertise on:

1) Amperometric method based on an enzyme biosensor for complex forming metal ions like nickel

2) Strip test with colormetric analysis

3) Plasma discharge atomic absortion and emission spectroscopy

4) Plasma, spark or laser induced breakdown spectroscopy

5) Optical transmission spectroscopy with complex forming reagents

On-line detection of toxic metals in waste water streams


Anodic stripping voltametry by screen printed electrodesBased on screen printed electrodes developed originally by University of Rome

Detection limit: ppb -level

•WORKING ELECTRODE

•COUNTER ELECTRODE

•REFERENCE ELECTRODE


Gold wire electrodeBased on a 3-electrode configuration with microwire technology originally developed byUniversity of Liverpool. The solution has an integrated solution to prevent contamination of the sensor surface and to increase the selectivity, sensitivity and stability

First prototype

Detection limit: sub-ppbPotential

Cu

rren

t

tap water

0.00 0.05 0.10 0.15 0.20 0.25

V

20

40

60

80

nA

Cu 104,37 ± 5,85 ppb

Three metal simultaneously5, 10, 20 ja 50 ppb


Calibration curve for Ni

[Ni] (ppm)

0 1 2 3 4 5 6

Re

lative

cu

rre

nt

(%)

0

20

40

60

80

100

120

140

Calibration curve for Ni using sarcosine oxidase

Linear regression

Enzyme-based sensors

Enzyme (Sarcosine oxidase) produces hydorgen peroxide that can be measuredamperometrically using a modified electrode (Prussian Blue). Nickel inhibits enzymeactivity, resulting in lower response detected.


Ni sensorNi detection based on regenerable bismuth coated electro chemical sensor


Field usable optic online measuring instrument for liquidsThe instrument can be used to measure metal concentrations in liquid samples with a reagent that forms complexes with metals. The formed complexes absorb light in the visible area. Measurements are based on optical spectroscopy within wavelength range 200 … 850 nm. Fouling of optical surfaces is controlled with a cleaning solution.

Figure shows the spectra of several concentrations of nickel with PAR (4-(2-pyridylazo)resorcinol) reagent.


2011

2012

2013

CEMIS has develop a fast and reliable on-line measurement system fordetermination of trace metal content in water. The measurement devicehas passed several field tests in order to evaluate the compatibility of thetechnique in harsh conditions. The solution will be commercialized by theend of year 2015.

Key features:

Analysis is based on electrochemical technique (square wave anodic stripping voltammetry/potentiometry/electrical impedance spectroscopy)

Several metal analytes (e.g. Cu, Pb, Zn, Ni, Hg …)

Low detection limit < µg/L (sub-ppb) for metals

Fast analysis < 5 minutes

No toxic reagents used, Mercury-free operation

Automated sampling

Integrated sample pre-treatment technology

Low maintenance and running costs

Wireless data transfer + remote control

Battery-operated

Robust design, suitable for field use

Automated online analyzer


0

0,5

1

1,5

2

2,5

3

6.10. 7.10. 7.10. 8.10. 8.10.

Continuous Chloride Measurement

mg/

l

0

10

20

30

40

50

60

70

6.10. 7.10. 7.10. 8.10. 8.10.

Continuous Sulfate Measurement

mg/

n=244 SO₄²¯ mg/l

Average 57,5

StDev 1,79

%StDev 3 %

Min 54,0

Max 62,8

On-line Capillar ElectrophoresisAnalyzer

n=244 Cl¯ mg/l

Average 2,2

StDev 0,25

%StDev 11 %

Min 1,7

Max 2,8


A technique to detect fouling on optical sensorsA technique has been developed to detect contamination on optical surfaces and correct theoptical measurement signal accordingly.

Measured reflectance Index of contamination

0 20 40 60 800.15

0.2

0.25

0.3

0.35

Aika

R

37

likaantunut puhdas

0 20 40 60 800

0.01

0.02

0.03

Aika

Lik

ain

dek

si

0.0058


Mobile Monitoring Station


Focus on reliable measurements

Evaluation of the combined measurement uncertainty of Cu-sensor


Interoperability

Reliability

Sensitivity

Selectivity

Specificity

Detectionspeed

Remote use

Wide detection

rangeLow

invest.&oper. costs

Small size

Minimalenergy

consumption

Reagentfree

No moving

parts

Real-time

Multi

sensing

Robust

ness

”Ultimate”Sensor

Vision of Future Sensor…


Just one dream…

… wireless, self-powered, robust, reliable, self-calibrating sensor network for water quality.

…Vision of Future Sensor


Implementing Results of Cleen/MMEA -Programme


Director Risto Oikari

CEMIS (Ketunpolku 3, FIN-87101 KAJAANI, FINLAND)

Tel.: +358-44-7101410, e-mail: [email protected]

Thank you!

Reliable On-line Measurements for Demanding Conditions

reliable on-line sensing

Environment