ENVIRONMENTAL IMPACT OF THE

UTILIZATION OF

GEOTHERMAL AREAS ıN TURKEY

Prof.Dr. Alper BABA Izmir Institute of Technology

Geothermal Energy Research and Application Center

alperbaba@iyte.edu.tr

WHAT IS GEOTHERMAL ENERGY?

A clean, renewable and environmentally benign energy

source based on the heat in the earth

Used in 58 countries of the world. Known in over 80

Electricity generation in 24 countries

Direct heating use in 78 countries

APPLICATION OF GEOTHERMAL

RESOURCES

Geothermal resources have long been used for direct heat extraction for district urban heating, industrial processing, domestic water and space heating, leisure and balneotherapy applications. Geothermal fields of natural steam are rare, most being a mixture

of steam and hot water requiring single or double flash systems to separate out the hot water, which can then be used in binary plants or for direct heating.

Re-injection of the fluids maintains a constant pressure in the

reservoir, hence increasing the field’s life and reducing concerns about environmental impacts

GEOTHERMAL ELECTRICITY

INSTALLED CAPACITY MWE (2013)

Kenya 167

Mexico 958

China 24

Russia 82

Philippines 1904

Indonesia 1197

Turkey 243.35

Ethiopia 7.3

Italy 843

Guadeloupe 4

Costa Rica 166

El Salvador 204

Guatemala 52

New Zealand 437

Australia 1.1

Iceland 575

Japan 536

USA 3093

GEOTHERMAL DIRECT USE

ENERGY PRODUCTION GWH/YR (2010)

Kenya

Mexico 1117

China 20931

Russia 1707

Philippines

Indonesia

Turkey 10247

Thailand

Ethiopia

Poland

Tanzania Burundi

Uganda

Eritrea Djibouti

Vietnam

Latvia

Lithuania

Slovakia Romania Ukraine

Georgia

Iran

Pakistan

Nepal

Algeria

Tunisia

Macedonia

Serbia

Guadeloupe

Costa Rica

El Salvador

Guatemala

Bulgaria

Greece

Egypt Jordan

Mongolia

USA 15710

Iceland 6767

Japan 7139

Australia

New Zealand 2654

Canada 2465

Sweden 12584

Germany 3546

Switzerland 2143

ENVIRONMENTAL CONCERNS

Surface disturbances

Physical effects - fluid withdrawal

Noise

Thermal pollution

Chemical pollution

Protection

Social and economic effects

TURKEY Turkey is one of the most seismically active regions in the world.

Its geological and tectonic evolution has been dominated by the

repeated opening and closing of the Paleozoic and Mesozoic oceans

(Dewey and Sengör, 1979; Jackson and Mc Kenzie, 1984).

It is located within the Mediterranean Earthquake Belt, whose

complex deformation results from the continental collision between

the African and Eurasian plates (Bozkurt, 2001).

The border of these plates constitutes seismic belts marked by

young volcanics and active faults, the latter allowing the

circulation of water as well as heat.

The distribution of hot springs in Turkey roughly parallels the

distribution of the fault systems, young volcanism, and

hydrothermally altered areas

GEOLOGICALLY, TURKEY IS COMPOSED OF AEGEAN AND ANATOLIAN

PLATES WHICH COVER THE WESTERN AND CENTRAL PARTS OF THE

COUNTRY.

North

Anatolian

Fault

East

Anatolian

Fault

Horst

Graben

System

Western Anatolia Central

Anatolia

GEOLOGICAL MAP OF TURKEY

MTA, 1995, Şimşek, 1982, 2010

More than 1000 hot spring can be seen in

Turkey

Geothermal Resources in

Turkey

More than 1000 hot spring can be seen in Turkey. Temperatures ranging from 25°C to as high as 287 °C, fumaroles, and numerous other hydrothermal alteration zones.

Bitlis-Nemrut-

Tendürek

Çanakkale-Tuzla (173 0C)

Aydın-Germencik 232 0C

İzmir-Seferihisar 153 0C)

İzmir-Dikili-Bergama 150 C)

Aydin-Salvatlı 171 0C)

Denizli-Kizildere 242 oC

Kütahya-Simav 162 0C

Nevşehir-Acıgöl

High enthalpy resource in Turkey Alaşehir-Manisa (287 0C

Göbekli-Manisa (182 0C

Geothermal Field (°C) Geothermal Field (°C)

Manisa-Alaşehir-Köseali 287 Kütahya-Simav 162

Manisa Alaşehir X 265 Aydın-Umurlu 155

Manisa-Salihli-Caferbey 249 İzmir-Seferihisar 153

Denizli-Kızıldere 242 Denizli-Bölmekaya 147

Aydın-Germencik-Ömerbeyli 239 Aydın-Hıdırbeyli 146

Manisa-Alaşehir-Kurudere 214 İzmir-Dikili-

Hanımınçiftliği

145

Manisa-Alaşehir-X 194 Aydın-Sultanhisar 145

Aydın-Yılmazköy 192 Aydın-Bozyurt 140

Aydın-Pamukören 188 Denizli-Karataş 137

Manisa-Alaşehir-

Kavaklıdere

188 İzmir-Balçova 136

Manisa-Salihli-Göbekli 182 İzmir-Dikili-Kaynarca 130

Kütahya-Şaphane 181 Aydın-Nazilli-Güzelköy 127

Çanakkale-Tuzla 174 Aydın-Atça 124

Aydın-Salavatlı 171 Manisa-Salihli-Kurşunlu 117

Denizli-Tekkehamam 168 Denizli-Sarayköy-Gerali 114

(Simsek et al., 2005)

Dora-1, Karadas,2012

Germencik, Wallace et al., 2009

(Inanli and Atilla, 2011)

Bereket, Karadas,2012 Dora-2, Tufekcioglu ,2010

2013 Update Results

-Geothermal Power Generation in Turkey-243.35MWe

Location Power plant Startup date

Reservoir temperature

(°C)

Average Reservoir

temperature (°C)

Power capacity (MWe)

Denizli Kızıldere I Kızıldere II Sarayköy

Aydın/Sultanhisar

Salavatlı Salavatlı Salavatlı

Aydın/Germencik

Ömerbeyli Hıdırbeyli Bozkoy Bozkoy

Çanakkale

Tuzla Total

Zorlu - Kızıldere Zorlu - Kızıldere

Bereket

Dora-1 Dora-2 Dora-3

Gurmat Irem

Sinem Deniz

Tuzla

1984 2013 2007

2006 2010

2013

2009 2011 2012 2012

2010

242

- -

172 176

-

232 190

- -

174

217

- 145

168 175 -

220 170

- -

160

17.4 60 7.5

7.35 11.2 17

47.4 20 24 24

7.5

243.35

Greenhouse Agriculture Thermal Tourism

• Currently, the country’s geothermal resources are primarily used for heating, which accounts for over % 90 of total direct use,

DIFFERENT APPLICATION

Powder material

Reduce the industrial waste (Copper)

Salt production

ENVıRONMENT PROBLEMS

Turkey is one of the fastest growing power markets in the world and is facing an ever-increasing demand for power in the coming decades

Geothermal development over the last forty years in Turkey has shown that it is not completely free of impacts on the environment

GEOLOGICAL MAP

OF WESTERN

TURKEY

(Baba and Sözbilir , 2012; Chemical Geology)

HYDROGEOCHEMIC

AL PROPERTIES OF

GEOTHERMAL

SYSTEM IN

WESTERN TURKEY

(Baba and Sözbilir, 2012; Chemical Geology)

HEAVY METALS

Arsenik

Stronsiyum

(Baba and Armansson, 2008; Energy Source)

(Baba and Armansson, 2008; Energy Source)

HYDROGEOCHEMIC

AL PROPERTIES OF

GEOTHERMAL

SYSTEM IN

WESTERN TURKEY

(Baba and Sözbilir, 2012; Chemical Geology)

SCALING AND CORROSıON

Turkish geothermal operators claim to have virtually overcome the consequences

of scaling and corrosion in both high and low temperature wells (Demir et al., 2013;

Geothermic)

GEOTHERMAL FLUIDS ENCOUNTERED IN TURKEY CAN BE CLASSIFIED

CHEMICALLY AS %95 INCRUSTING AND TWO TO THREE GEOTHERMAL FIELDS HAVE HIGHLY CORROSIVE

GEOTHERMAL FLUIDS.

IN THREE OF THE 140 GEOTHERMAL FIELDS, GEOTHERMAL FLUID

CONTAINING TOTAL DISSOLVED SOLIDS (TDS) EXCEEDS 5000 PPM.

Turkish geothermal

operators claim to have

virtually overcome the

consequences of scaling

and corrosion in both high

and low temperature wells,

and scientific research.

GEOTHERMAL FLUID COMPOSITIONS

The vast majority of geothermal fluids is of meteoric origin.

However, isotopic studies suggest that a small fraction (5-10%) may emanate from other sources, magmatic, juvenile, fluids or host sediments (connate or formation water)

Most geothermal fluids exhibit higher TDS contents than the original, cooler, intake waters.

GEOTHERMAL FLUID COMPOSITIONS

The amount and mature of dissolved chemical species depend on temperature, pressure, minimal-fluid equilibria and mixing with other waters.

One may logically infer that hotter fluids would display higher TDSs than cooler ones, an attribute however suffers many exceptions.

THE MAJOR CONSTITUANTS OF GEOTHERMAL

WATERS ARE;

Cations: Na, K, Ca, Mg, Li, Sr, Mn, Fe

Anions: Cl-, HCO3-, SO4

2-, F-, Br-

Non ionic: SiO2, B, NH3, gases

Minor constituants: As, Hg, heavy, often

toxic, metals

Damage occurs under the form of metal corrosion and deposition on exposed material surfaces of scale species.

Both phenomena may also coexist through deposition and/or entrainment of corrosion products.

Most commonly encountered damages address CO2/H2S corrosion, alkaline carbonate/sulfate, heavy metal sulphide and silica scale.

Source mechanisms are governed by pH, solution gases and related bubble point and (CO2) partial pressures, salinity, solubility products and of thermodynamic changes induced by the production and injection processes.

Corrosion and Scaling

CORROSION AND SCALING

Whereas scaling affects mainly high enthalpy systems,

a result of fluid flashing,

steam carry over and injection of heat depleted brines,

corrosion and, at a lesser extent though,

corrosion is the major damage in exploitation of low grade geothermal heat, known as direct uses.

Micro-biological activity, particularily sulfate reducing bacteria, can also be a significant corrosion contributor in such low temperature environments.

Scale Composition

CALCIUM SCALE INHIBITION

Four inhibition groups i. Threshold effect: the inhibitor acts a as salt

precipitation retarder. ii. Crystal distortion effect: the inhibitor interferes

with crystal growth by producing an irregular structure (most often rounded surfaces) with weak scaling potential.

iii. Dispersion: the polarisation of crystal surfaces results in the repulsion between neighbouring crystal of reverse polarities

iv. Sequestration or chelation: complexation with selected cations (Fe, Mg, etc…) leads to the formation of soluble complexes.

CORROSION PHAENOMENOLOGY

General (uniform) corrosion

Pitting corrosion

Crevice corrosion

Underdeposit corrosion

Galvanic corrosion

Impingement

Stress corrosion cracking (SCC)

CORROSION GOVERNING PARAMETERS

Temperature

pH

Oxygen concentration

Fluid velocity

Suspended solids

CORROSION INHIBITION (EXAMPLE)

CORROSION/SCALING

MONITORING PROTOCOLS

hydrodynamics: control of pressures and temperatures and

subsequent well, reservoir, geothermal network and heat exchanger

performances,

fluid chemistry: general and topical (selected indicators, HS-, S2-,

Fe3+, Fe3+, Ca2+, HCO3-, etc.) liquid and PVT (dissolved gas phase,

gas-to-liquid ratio, bubble point) analyses,

inhibitor injection concentrations: volume metering, flow

concentrations via tracing of the inhibitor active principle,

solid particle monitoring: concentrations (staged millipore

filtrations) and particle size diameters and distributions (optical

counting, doppler laser velocimetry),

microbiology: sulphate reducing bacteria numbering,

corrosion: measurement of corrosion rates (coupons, corrosion

meters),

down hole line integrity: electrical measurements, pressurisation

and/or tracer tests,

periodic well logging inspection

DEPOSITION STUDY

Themodynamics. Theory

Kinetics. Practice

In line coupons

Solids

Ageing. Laboratory simulation (Bench scale study)

Suspended tank

Full scale simulation

ANALYSIS OF SCALES

Microscopy

XRD

XRF

SEM

Microprobe

Wet chemical

EFFECT

Problematic in surface equipment and in connection with

disposal

Thermodynamic study to determine minimum temperature of

possible deposition

Bench scale study prior to ponding or re-injection to study rate under

different conditions

SILICA SCALE

SILICA REMOVAL/CONTROL

l Prevention:

– t > t AS

– Inhibitors, e.g hydroxy -ethyl-cellulose, ethylene

oxide, -C-O-C- group compounds

l Removal: Difficult

– Physical: drilling, scraping, hydroblasting ,

cavitation descaling

– Chemical: HF, hot NaOH ; undesirable

IRON SILICATES (OXIDES, CARBONATES)

In high temperature brines, e.g Tuzla, Salton Sea,

Djibouti, Milos. Also where volcanic activity has

interfered, e.g Centreal and Eastern Anatolia

Temperatures at least 50°C higher than for formation

of simple silica deposits

Proposed mechanism:

OFeOH•H2O + Si(OH)4 Fe(OH)3•SiO2 + 2H2O

When formation starts extent is great

IRON COMPOUNDS: Fe/Si RATIO,

CONTROL AND REMOVAL

Fe/Si RATIO (mole/mole):

0.15 at 105°C, 1.00 at 220°C (Tuzla)

Control and Removal

Pressure control

Acid

Reducing agents, e.g. Na formate, as

inhibitors

Drilling out

SULPHIDES

PbS (galena), ZnS (sphalerite), CuS covellite), Cu2S

(chalcocite), SbS2 (stibnite, in Mt Amiata, Italy),

CuFeS2 (chalcopyrite), FeS2 (pyrite), FeS (pyrrhotite)

by reaction of metal(s) with H2S.

Saline solutions, effect of volcanic gas

Lower temperature lower solubility

Milos: Not directly on metal. Order of scales from

wellhead to outflow: Galena, sphalerite, Fe-Si, SiO2

BLACK DEATH Galena on deposition coupon

Black death Picture from Haldor Arrmansson

Deposition at different pressures

Branched line

Pressure controlled by orifices.

Coupons inserted after each orifice

Flow regulated by RJ-pipes,

critical lip pressure monitored

Pictures from Haldor Arrmansson

Fe-Si deposit Pseudo scales

Pictures from Haldor Arrmansson

CALCITE SCALING

Flashing CO2 stripping and pH increase,

causing calcite deposition

Ca+2 + 2HCO3- CaCO3 + CO2 +H2O

Increasing temperature decreasing solubility

Extent of supersaturation can be calculated

Control Inhibition:Organic phosphonates (success claimed);Synthetic polymers

(e.g. polyacrylamide); Organic polymers (e.g. polycarboxylic acids);Sequestering

agents (e.g. EDTA, polyphosphates (successful in low temperature situations));

HCl: Success claimed but care needed

Removal Drilling out

HCl treatment

CALCITE

MAGNESIUM SILICATES

Formed upon heating of silica containing ground water or

mixing of cold ground water and geothermal water

Form at relatively high pH

Well known where

geothermal water used to

heat groundwater

Avoid mixing and keep pH

low

CORROSIVE SPECIES

O2: at low temperatures; H+ (pH): Low pH favours cathodic half-reaction; Cl: Fe+2 + Cl- FeCl+ favours anodic half-reaction; CO2: Controls pH and favours last cathodic half-reaction. H2S attacks Cu, Ni, Zn, Pb

H2S, CO3-2 and SiO2 may form protective films on

steel

Fe+2 + HS- FeS + H+

Fe+2 + H3SiO4- FeSiO3 + H+ + H2O

Fe+2 + HCO3- FeCO3 + H+

MODES OF CORROSION

Uniform

Pitting

Crevice

Stress cracking

Erosion

Sulfide stress cracking

Hydrogen blistering

Intergranular

Galvanic

Fatigue

Exfoliation

MONITORING AND CONTROL

COUPONS

Wellhead fluid

Two phase flow lines

Flashed liquid

Steam

Condensate

Cooling water

KEEP OXYGEN OUT

INSULATE Cl-RICH DRY STEAM

SPECIMENS Type

Coupons

U-bend specimens

Notched specimens

Fatigue specimens

Number

Vendor of installation, plant owner,

contractor 1 set each

Test period. ½ year, 1 year, long-term: 1

set each

Fuji, 13% Cr

stainless steel

DIN X 20 Cr 13

(uncondensed

steam)

Virkir-Orkint

CrNiMo steel

30 CrNiMo 8

(DIN 17200)

(uncondensed steam)

Fuji CrMoNiV

steel

DIN 30 CrMoNiV

5 11

(uncondensed steam) Fuji Stainless steel

405

(uncondensed steam)

Fuji CrMoNiV

steel

DIN 30 CrMoNiV 5 11

(condensed steam)

Fuji Stainless steel

405

(condensed steam)

Fuji Stainless steel

304L

(condensed steam)

Fuji, 13% Cr

stainless steel

DIN X 20 Cr 13

(condensed steam)

Pressure Forces Acting on Casing

BURST COLLAPSE

24 May 2012

ALASEHIR

Geothermal development in the last forty years has shown that it is not completely free of adverse impacts on the environment.

These impacts are causing an increasing concern to an extent that may now be limiting development

The scarce data available shows that the thermal fluids contain trace elements (As, Cd, and Pb), which may affect soil and water.

Corrosion and Scaling still a big problem in the most geothermal fields.

All possible environmental effects should be clearly identified, and mitigation measures should be devised and adopted to avoid or minimize their impact.

Result and Conclusion