1. Technological Educational Institute of Crete
School of Applied Sciences
Department of Environmental & Natural Resources Engineering
Laboratory scale application of spectral induced polarization (SIP) method for environmental monitoring
Kirmizakis Panagiotis
MSc thesis
Supervising committee: Soupios Pantelis
Ntarlagiannis Dimitrios
Kalderis Dimitrios
September 30, 2016

2. Outline Introduction Methodology Experimental Details
SIP Sensitivity / Calibration
Environmental Applications - Results and Discussion
Conclusions and Future Work
Acknowledgements
September 30, 2016

3. Introduction Geophysics …
“… the application of physical theories to discover the properties of the earth ” (Society of Exploration Geophysics)
Applications
Geosoft.com
Engineering – geotechnical studies
Mineral exploration
Hydrogeology
Archaeological prospections
Environmental monitoring
September 30, 2016

4. Introduction Environmental monitoring using geophysical methods …
“… geophysical approaches into characterization and monitoring the quality of the environment ” (EEGU)
Monitoring Contamination and remediation
Groundwater
Landslides
September 30, 2016

5. Introduction huge waste production in a relatively short time OMW
1 ton olive oil production  ~1.5 ton dry organic pollutants
Physico-chemical characteristics
Dark brown color, foul-smelling and turbid liquid
Includes emulsified grease
High Biochemical Oxygen Demand (BOD g/l )
High Chemically Oxygen Demand (COD g/l)
Phenolic compounds (<700 mg/Kg)
Acid PH (<6)
High electrical conductivity ( μS/cm)
Production of olives, olive oil and olive acreage (FAOSTAT, 2012
September 30, 2016

6. Introduction Disposal of OMW Evaporation ponds
Disposal in soil and torrents
Incineration given the high organic load (fuels cost, gas emissions)
Phenolic compounds
Phytotoxic and antimicrobial effects
Serious degradation of soil and groundwater quality
Crete, Greece
Palestine
Tunis, Tunisia
September 30, 2016

7. Introduction Geophysical methods used Electrical Methods
Induced Polarization
Electrical Methods
The voltage delay after current is switched off (or turned on)
Electrical Resistivity Imaging
September 30, 2016

8. Methodology Induced Polarization Conventional resistivity arrays
Time domain (current is switched off, the IP effect is measured by measuring the area under the decay curve)
Frequency domain
Traditional variable-frequency IP (using two or more frequencies of <10 Hz) (obsolete)
Spectral IP (typically measure phases and amplitude at frequencies 10-3 to 4·103 Hz)
Conventional resistivity arrays
Most commonly dipole-dipole configuration
Schlumberger arrays for broad reconnaissance surveys
Hybrid arrays using multichannel instruments
Applications
Mineral exploration
Environmental applications (last couple of decades)
September 30, 2016

9. Methodology Origin of IP (Macroscopic)
The ground acts somewhat like a capacitor
Disseminated (poorly conductive) ore body is polarized (develop surface changes) by the imposed current;
When the current is switched off, the charges cause transient current through the conductive overburden.
These currents flow in the same direction and cause the overvoltage effect.
September 30, 2016

10. Methodology Origin of IP (Microscopic) in absence of metallic minerals
Pore throat polarization mechanisms
that are the result of ion accumulation and reduced ion mobility at pore throats
Electrical Double Layer (EDL) conduction and polarization mechanisms
Ntarlagiannis D., 2009
restricted displacement of ions within electrical double layer of interconnected pore surface following application of an alternating electric current
Slater & Lesmes, 2000
September 30, 2016

11. Methodology Measurement principles
Complex conductivity expressed by a real (σ’) and a imaginary (σ’’) component.
We measure magnitude |σ| and phase φ and calculate the real and imaginary component.
V (ω)
I (ω)
𝜎 = 1 |𝜌| = 𝜎 ′ 𝜎 ′′ 2
magnitude
polarization
ϕ=arcta n 𝜎 ′′ 𝜎 ′
(Joseph S., 2016)
phase lag
ohmic conduction
September 30, 2016

12. Experimental Details
Acrylic chambers (h = 25 cm, d = 5 cm, V = 480 cm³)
Current electrodes: Ag-AgCl electrodes
Potential electrodes: Ag-AgCl electrodes
Our sample holders:
I +
V +
V -
(A)
(B)
I -
(C)
September 30, 2016

13. Experimental set up of the measurements.
Experimental Details
Portable SIP Field/Lab Unit (PSIP)
Frequency range: 0.01 – Hz
Room temperature: 23 ± 1 C°
Our measurement set-up:
I +
V +
V -
Field/Lab Spectral Induced Polarization (PSIP) instrument
I -
Experimental set up of the measurements.
September 30, 2016

14. SIP Sensitivity / Calibration
Geometric Factor
For the purpose of measurements, three different solutions of known concentration (79.1 µS/cm, 282 µS/cm, 910 µS/cm) were prepared using the method ASTM D
𝐹𝑙𝑢𝑖𝑑 𝑐𝑜𝑛𝑑𝑢𝑐𝑡𝑖𝑣𝑖𝑡𝑦= 1 𝑅𝑒𝑠𝑖𝑠𝑡𝑎𝑛𝑐𝑒 ∙𝐾(𝑔𝑒𝑜𝑚𝑒𝑡𝑟𝑖𝑐 𝑓𝑎𝑐𝑡𝑜𝑟)∙
September 30, 2016

15. SIP Sensitivity / Calibration
Sensitivity Impact of changes in grain size
Induced polarization dependence on grain size
September 30, 2016

16. SIP Sensitivity / Calibration
SIP response at different contaminant concentrations
Different concentration OOMW solutions.
Dilution
Conductivity
TDS
OOMW Sol. 1
0 %
12090 μS/cm
6.40 ppt
OOMW Sol. 2
25 %
10000 μS/cm
5.00 ppt
OOMW Sol. 3
50 %
7140 μS/cm
3.57 ppt
OOMW Sol. 4
75 %
4000 μS/cm
2.01 ppt
September 30, 2016

17. Environmental Applications - Results and Discussion
1. Phytoremediation …
… uses plants to clean up contaminated sites
24 h ambient conditions
4 outflow solution samples in period of 12 days
Phytoremediation tank (TUC)
Phytoremediation process (Phytoremediation Citizens’ Guide, EPA)
September 30, 2016

18. Environmental Applications - Results and Discussion
1. Phytoremediation - Results
Chemical results from phytoremediation treatment
Day
TDS (ppt)
COD (mg/L)
EC (μS/cm) 
6.2
49723
12400  3
3.75
10410
 7500 6
4.3
13821
 8700 9
3.91
12657
 7840 12
3.8
8478
 7780
Future Research ?
in-situ SIP measurements in the phytoremediation tank that could give us information about the interface changes during the phytoremediation processes.
Μπορείς να εξηγήσεις γιατί με το phytoremediation πέφτει το EC ?
September 30, 2016

19. Environmental Applications - Results and Discussion
2. Biochar - “black gold of agriculture” (ACS) …
… a highly porous charcoal made from organic waste. It is derived as a by-product of pyrolysis (heating biomass with little or no oxygen).
Properties …
High carbon content
Resistant to biodegradation
Significant adsorptive qualities (similar to activated carbon)
Nutrients (& contaminants) essentially lock on to the structure
Increases moisture holding capacity
Enhances microbial biomass
Biochar used in potting mix
September 30, 2016

20. Environmental Applications - Results and Discussion
2. Biochar
Prepare from blending of paper sludge (50%) and wheat husks (50%) (Bachmann et al., 2015)
3 biochar amended columns (5%, 10%, 25) and 1 control column (100% Ottawa sand)
10 days treatment
Different concentrations of biochar in the measured columns
Different Concentrations of Biochar
Permeability
Column 1
Ottawa sand + 0% w/w biochar
4.27 · 10-4 m/sec
Column 2
Ottawa sand + 5% w/w biochar
4.13 · 10-4 m/sec
Column 3
Ottawa sand + 10% w/w biochar
3.73 · 10-4 m/sec
Column 4
Ottawa sand + 25% w/w biochar
3.04 · 10-4 m/sec
Mixture of biochar with Ottawa sand
September 30, 2016

21. Environmental Applications - Results and Discussion
2. Biochar – SIP response
September 30, 2016

22. Environmental Applications - Results and Discussion
2. Biochar – Chemical analysis
Chemical analysis to the initial OOMW and the outflows after 10 days treatment in the different biochar concentrations.
Initial OMW
0% w/w Biochar
5% w/w Biochar
10% w/w Biochar
25% w/w Biochar
After 10 days pH
4.88
4.92
6.57 8
5.9
DO (dissolved oxygen), mg/L
1.47
4.1
4.3
3.5
4.6
EC (electrical conductivity), mS/cm
9.4
9.6
10.9
9.1
12.5
Phenols, mg/L
2485
1921.6
850.7
310.9
1059.6
Total COD, mg/L
39400 -
Soluble COD, mg/L
37600
36500
27100
16500
30600
NO3, mg/L 98 37 28 14 33
P, mg/L
194
164
106
29.5
120
Total Dissolved Solids, ppt
4.8
4.84
5.5
4.57
6.26
Visual evident suggest that 10% w/w biochar succeed the decontamination results.
September 30, 2016

23. Environmental Applications - Results and Discussion
2. Biochar – Further chemical analysis
XRD diagram for the 4 samples
SEM images of the biochar samples
September 30, 2016

24. Conclusions and Future Work
SIP method usually applied to biogeophysical (combination of geophysical and microbial interactions) surveys and can be used as a non-destructive way for environmental monitoring and significantly contribute to determine the progress step between of aerobic - anaerobic digestion without using the conventional chemical approaches.
This work is very innovative since only few times (in national and international level) the integration of SIP method with biochar is presented.
Future works : Use of SIP to determine the biochar quality.
September 30, 2016

25. Acknowledgments
Prof. Pantelis Soupios and Asst. Prof. Dimitrios Kalderis for their substantial assistance with problems encountered during my thesis. The encouragement during my under-graduate level was continuous and I thank them for the confidence they showed me at the Master.
Prof. Lee Slater and Assoc. Prof. Dimitrios Ntarlagiannis for supporting my research visit to Rutgers University and their willingness to teach me the SIP method.
Prof. E. Gidarakos from TUC and the PhD candidate F. Pellera for their help in the Chemical analysis during the biochar treatment.
Prof. N. Kalogerakis from TUC and the Ph.D. candidate M. Petousi for the provision of ΟOMW samples from the phytoremediation experiment performed on an experimental tank.
Assoc. Prof. Evert Elzinga from Rutgers University for the IR and XRD analysis.
September 30, 2016

26. THANK YOU FOR YOUR ATTENTION
September 30, 2016