Pengetahuan Dasar Batubara

Batubara termasuk dalam batuan sedimen yang dibentuk dari hasil pengubahan sisa-sisa tumbuh-tumbuhan yang terjadi selama puluhan atau ratusan juta tahun.Sesuai dengan bahan asalnya batubara terdiri dari elemen-elemen arang (karbon), oksigen, belerang, hidrogen, dan beberapa mineral logam dalam bentuk dan jumlah bayangan (traces). Dengan demikian kualitas batubara tergantung dari jenis bahan asalnya dan peningkatan mutu oleh faktor geologi termasuk gradien geotermal dan sebagainya.

COMPOSITION OF COALCOMPOSITION OF COAL

COAL

LOI : loss on ignition

Mineral MatterPure Coal

(C,H,N,O,S,N, Trace elements)Moisture

Ash LOI Volatile Matter Fixed CarbonInherent Moisture

Adherent Moisture

Kandungan Unsur Kimia Dalam Batubara

Secara kimia, batubara tersusun atas tiga komponen utama, yaitu:

1. Air yang terikat secara fisika dan dapat dihilangkan pada suhu sampai 105 o C disebut Moisture;

2. Senyawa batubara atau coal substance atau coal matter;

3. Zat mineral atau mineral matter

Total Moisture

FreeMoisture

ResidualMoisture

OrganicMatter

(pure coal)

VolatileMatter

Fixed Carbon

Volatile

MM

Ash

MineralMatter

Raw Coal Air-dryCoal

DryCoal

RawCoke

PureCoke

SKEMA SUSUNAN KIMIA BATUBARA

Moisture terdiri dari satu senyawa kimia tunggal , wujudnya dapat berbentuk air dalam batubara, berbentuk senyawa teradsorpsi, dan sebagai senyawa yang terikat secara kimia.Sebagian dari moisture merupakan komponen dari zat mineral dan tidak terikat pada batubara.

Moisture yang datang dari luar yaitu pada waktu batubara ditambang, diangkut atau kehujanan selama penyimpanan disebut Free Moisture (moisture jenis ini dapat dihilangkan dengan cara dikering-udarakan)

Total Moisture adalah penjumlahan dari free moisture dan moisture in air-dried sample atau residual moisture

Proses Pembentukan Endapan Batubara

Tahapan Dalam Proses Pembentukan Batubara

• TIDAK TERBARUKAN • TERJADINYA DITENTUKAN OLEH

PROSES GEOLOGI: - SIFAT KIMIA DAN FISIKA

TERTENTU - KUANTITAS DAN KUALITAS

TIDAK MERATA - PENYEBARAN DAN BENTUK

TIDAK TERATUR ( TIDAK MENGENAL BATAS

ADMINISTRASI )

• UMUMNYA MEMPUNYAI RISIKO TINGGI YANG

MEMERLUKAN TAHAPAN KEGIATAN SISTIMATIK

PEMETAAN GEOLOGI, PENYELIDIKAN UMUM,

EKSPLORASI, STUDI KELAYAKAN,

KONSTRUKSI, EKSPLOITASI, PENGOLAHAN

DAN TRANSPORTASI • NILAI EKONOMINYA SANGAT

DIPENGARUHI OLEH TEKNOLOGI,

POLEKSOSBUD, KEBIJAKAN FISKAL, INDUSTRI, PASAR

DAN GEOGRAFI ( INFRASTRUKTUR / LOKASI )

6

Cibuniasih(Pb, Au)

9

11

N

SUNDA - BANDA

C u

Tangse(Cu)

Rawas(Au)

S n

Bangkinang(Sn)

S n

S n

Lebong Tandai(Au, Ag)

Cikotok(Au)

Lampung(Au)

Singkep(Sn)

3S n

Kelapa Kampit(Sn)

G. Pongkor(Au,Ag)

S. Liat & Belinyu(Sn)

Salopa/Cineam(Au)

G. Bawang(Mo)

Sanenrejo(Cu, Au)

Selogiri(Au)

Barru(Cr)

Meratus(Ni)

MT. Muro(Au,Ag)

Cempaka(Pt)

Kelian( Au)

Sekko(Cu)

Batuhijau(Cu,Au)

Malala(Mo)

Baturape (Pb)

Sangkaropi(Cu)

Bulagidun(Cu,Au)

Tapadaa(Cu)

G. Pani(Au, Cu)

Ratatotok(Au)

Gosowong(Au)

Soroako(Ni, Co)

Lerokis/Kalikuning (Au, Ag)

Pomala(Ni,Co)

Kaputusan(Cu)

Loloda(Cu,Mn)

0 600300

KilometerTanjung Buli

(Ni, Co)

P. Gebe(Ni,Co)

G. Bijih(Cu, Au)

Grasberg(Cu, Au)

A u

Peg. Cycloop(Ni,Co)

Granit Tersier

KETERANGAN

Vulkanik Tersier

Vulkanik Kuarter

Batuan Basa-Ultrabasa

Granit Pra Tersier

Vulkanik Pra Tersier

Sedimen Tersier-Kuarter

Sedimen dan VulkanikPaleozoikum - Mesozoikum

Sedimen dan VulkanikMesozoikum - Kenozoikum

Ni-Co dalam batuan Ultramafik

Au-Cu dalam batuan Asam-Intermediet

Cr-Fe dalam batuan Ultramafik

Bauksit-Timah dalam Granit

Au- Cu - Mo Porpiri dalam batuan Granit

Keterdapatan Mineral

Tambang Aktif

SIMPLIKASI ZONA MINERALISASI BERHUBUNGAN DENGAN BATUAN INDUK (DIADOPSI DARI BEBERAPA SUMBER)

Kilometer

N

0 250 500

Busur Aceh

Busur Kalimantan Tengah

Busur Sumatera - Meratus

Busur Sunda - Banda

Busur Sulawesi Timur - Mindanau

Busur Halmahera

Busur Irianjaya Tengah

C u

Tangse(Cu)

Rawas(Au)

S n

Bangkinang(Sn)

S n

S n

Lebong Tandai(Au, Ag)

Cikotok(Au)

Lampung(Au)

Singkep(Sn)

3S n

Kelapa Kampit(Sn)

G. Pongkor(Au,Ag)

S. Liat & Belinyu(Sn)

Salopa/Cineam(Au)

G. Bawang(Mo)

Sanenrejo(Cu, Au)

Selogiri(Au)

Barru(Cr)

Meratus(Ni)

Sumatera - Meratus Arc

MT. Muro(Au,Ag)

Cempaka(Pt)

Kelian( Au)

Sekko(Cu)

Batuhijau(Cu,Au)

Malala(Mo)

Baturape (Pb)

Sangkaropi(Cu)

Bulagidun(Cu,Au)

Tapadaa(Cu)

G. Pani(Au, Cu)

Ratatotok(Au)

Gosowong(Au)

Soroako(Ni, Co)

Lerokis/Kalikuning (Au, Ag)

Pomala(Ni,Co)

Kaputusan(Cu)

Loloda(Cu,Mn)

0 600300

KilometerTanjung Buli

(Ni, Co)

P. Gebe(Ni,Co)

G. Bijih(Cu, Au)

Grasberg(Cu, Au)

A u

Peg. Cycloop(Ni,Co)

KETERANGAN

MIOSEN AKHIR - PLIOSEN

PALEOSEN - TERSIER TENGAH

KAPUR AKHIR

Keterdapatan Mineral

Tambang aktif

PENYEBARAN BUSUR MAGMATIK BERHUBUNGAN DENGAN MINERALISASI DI INDONESIA

RISIKORISIKO BIAYABIAYA

WAKTUWAKTU (TH)(TH)00

PENYELIDIKANPENYELIDIKANUMUMUMUM

EKSPLORASIEKSPLORASI

22 55

STUDISTUDIKELAYAKANKELAYAKAN

SURVAI DASARSURVAI DASARGEOLOGIGEOLOGI

WILAYAHWILAYAHSURVAISURVAITINJAUTINJAU100 %100 %N HaN Ha

WILAYAHWILAYAHCADANGANCADANGAN

PERTAMBANGANPERTAMBANGAN

<10 %<10 %N HaN Ha

SUMBERDAYASUMBERDAYA TEREKATEREKA

SUMBERDAYA SUMBERDAYA TERTUNJUK/TERTUNJUK/TERUKURTERUKUR

CADANGAN CADANGAN TERBUKTITERBUKTI

ENDAPANENDAPANHIPOTETIK HIPOTETIK

77

KONSTRUKSIKONSTRUKSIDAN EKSPLOITASIDAN EKSPLOITASICADANGANCADANGANLAYAK TAMBANGLAYAK TAMBANG

1010

4040

2020

RISIKO DAN BIAYA EKSPLORASIRISIKO DAN BIAYA EKSPLORASISUMBERDAYA MINERAL DAN SUMBERDAYA MINERAL DAN

BATUBARABATUBARA

Klasifikasi Sumber Daya dan Cadangan PBB

Classification of CoalsClassification of Coals

Scientific classification

Commercial classification

Coalification High Low

Anthracite Bituminous Lignite Brown-Coal Peat

Utilization Coking coal for coke and gas

Stream coal for power generation

Anthacite for briquetting

Scientific ClassificationScientific ClassificationClassification Contents Etc.

RankVitrinte mean random refrectance (%)

Gross calorific value (MJ/kg)ECE-UN

Petrographic Content

Maceral group analysis

(vitirnite,liptinite,mmf volume %)ECE-UN

Grade Ash (mineral matter) content (%,db) ECE-UN

C% Carbon content (% daf)

Geological era Paleozoic, Jurassiera

Original plants Terrestrial, aqua plant

Scientific ClassificationScientific ClassificationESE-UN in Seam Coal Classification, 1993

R : Reflectance of vitrinite

R

High Rank Antharacite

Meta > 4.0

Ortho 2.5-4.0

Semi 2.0-2.5

Medium Rank Bituminous

Meta 1.4-2.0

Ortho 1.0-1.4

Semi 0.6-1.0

Low RankSub-bituminous

Lignite

0.4-0.6

0.4<

Commercial ClassificationCommercial Classification

1. Standard for coal classification

International classification

2. For utilization

Stream Coal, Coking Coal, Anthracite

3. By size

Run-of-mine Coal > 50 mm

Lump Coal 38-50 mm

Coarse Grain Coal 25-37 mm

Fine Grain Coal <25 mm

Small Coal >1-3 mm

Very Fine Coal < 3 mm

Proved Recoverable ReservesProved Recoverable ReservesWEC 1998WEC 1998

[Mtonnes]

Bituminous + Anthracite

Sub-bituminous

Lignite Total Share (%)

USA 111,338 97,472 33,327 246,643 25.1

Russian 49,008 33,700 10,450 157,010 16.0

Chinna 62,200 1,900 18,600 114,500 11.6

Australia 47,300 -- 41,200 90,400 9.2

India 72,733 -- 2,000 74,733 7.6

South Africa 55,333 -- -- 55,333 5.6

Germany 24,000 -- 43,000 67,000 6.8

Others 8,749 43,971 47,122 178,592 18.1

Word Total 509,491 279,021 195,699 984,211 100

Coal and Their UsesCoal and Their UsesHigh High

Carbon/Energy Content Moisture Content

(%:World Reserves)

Domestic/ Manufacture Power Generation Largely power

Uses Industrial of iron and stell Cement manufacture generation smokeless fuel Industrial isues

(Source:WCI,1996)

Coal

Hard Coal50%

Low Rank Coal50%

Sub-bituminous19%

Lignite31%

Anthracite-1%

Bituminous49%

Metallurgical(Coking Coal)

Thermal(Steam Coal)

Basis of AnalysisBasis of Analysis Received/sampled/dispatched base

Air dried base (a.d.)

Dried base (d.b.)

Dry,ash-free base (d.a.f.)

Dry,mineral-matter-free (d.m.m.f.)

LOI : loss on ignition

Ash LOI Volatile Matter Fixed Carbon Inherent MoistureAdherent Moisture

Mineral Matter Pure Coal (C,H,N,O,S,etc) Moisture

COAL

Coal Analysis by Different BaseCoal Analysis by Different Base

As received Dry basis Dry, ash free

Proximate Analysis (wt%)

Moisture

Ash

Volatile Matter

Fixed Carbon

3.4

9.5

20.6

66.5

---

9.8

21.3

68.9

---

---

23.7

76.4

Ultimate Analysis (wt%)

Carbon

Hydrogen

Oxygen

Nitrogen

Sulfur

77.29

4.59

5.61

1.73

1.31

80.00

4.36

2.69

1.79

1.36

88.69

4.83

2.99

1.98

1.51

Calorific Value (MJ/kg)

Gross 31.68 32.79 36.15

Classification of Coal in UseClassification of Coal in UseSteam Coal Direct use Pulverized coal combustion

Fluidized bed combustionStoker combustionPulverized coal injection

Processing CWM Atomizing combustionCCS Pulverizing coal combustion

Conversion Gasification Combined cycle generationRaw material for chemicals

Liquefaction Alternative fuel

Coking Coal Carbonization Coke Iron making

Tar Raw material for chemicals

Anthracite Carbon material, Briquette

Example of Coal Quality for Power GenerationExample of Coal Quality for Power Generation

Evaluation Items Unit LimitGross calorific value (a.d.) Kcal/kg > 6,200

Total moisture (a.d.) Wt% < 20

Fuel ratio (FC/VM) --- < 2.2

Nitrogen (d.b.) Wt% < 1.7

Total sulfure Wt% < 1.0

Size distribution(-2mm) Wt% < 30

Ash / Initial deformation temp. °C > 1,150

Ash / Hemisphere temp. °C > 1,150

Na2O in ash Wt% < 2.0

Basicity of ash (CaO+MgO) / Fe2O3 --- < 1.0

Ash electric resistivity Ohm-cm < 1013

Coal Properties Required for CombustionCoal Properties Required for Combustion

Chemical Properties :

1. Total moisture

2. Ash content

3. Volatile matter

4. Calorific value

5. Sulfur content

6. Chlorine content

7. Trace element

8. Swelling and agglomerating behavior

9. Reflectance and petrographic content

Ash Properties :

1. Ash composition

2. Ash fusion temperature

3. Slagging and fouling Indices

4. Ash electric resistivity

Physical Properties :

1. HGI

2. Abrasion index

3. Friability

4. Dustiness

Evaluation Indices for CombustionEvaluation Indices for Combustion

Evaluation Items Indices

Combustibility (burn out) Fuel ratio (FC/VM), VM

NOx emissions Nitrogen content, Fuel ratio

Slagging property Ash fusion temp.,B/A ratio, Slagging index

Heat transfer property (Slagging&Fouling property)

Electrostatic precipitabilityAsh composition, Particle size profile, Intrinsic electric resistance

Grindability HGI

Handling property Moisture, Particle size profile, Fine particle

Spontaneous combustibility O/C, VM, Fuel ratio

Coal dust dispersion Moisture, HGI, Fine particle

Coal Properties for Other UsesCoal Properties for Other Uses

1. Gasification

More active sites

Higher porosity

Higher calcium content

Low ash fusion temperature

2. Liquefaction

High volatile matter

High vitrinite content

Low ash content

High ash fusion temperature

Environmental Impact of CoalEnvironmental Impact of Coal

3. Steel-making1) Chemical properties

2) Rheological properties

3) Petrographical composition

4) Coke strength prediction

Environmental Impact of CoalEnvironmental Impact of Coal

1. Coal production

Dust, Mine waste disposal, Mine water drainage

2. Coal preparation

Solid waste disposal, Liquid waste disposal,

Noise and vibration, Process water,

Particulate and gaseous effluents

3. Coal transportation and storage

Dust, Pipeline slurry, Spontaneous combustion,

Surface water run - off

4. Coal utilization

CO2, SOx, NOx, Solid waste disposal

ENVIRONMENTAL REGULATIONENVIRONMENTAL REGULATION

NOx, Sox, Dust Trace Element

Present Regulation Present Regulation (ash Disposal) NOx ≈ 20 ~ 50 ppm Pd < 0.3 mg/l, Cd < 0.3 mg/l SOx ≈ 20 ~ 50 ppm Se < 0.3 mg/l, Hg < 0.005 mg/l Dust ≈ 10 ~ 20 mg/Nm3 As < 0.3 mg/l, Cr < 1.5 mg/l

Future Regulation Future Regulation NOx ≤ 10 ppm SOx ≤ 10 ppm Waste Water B, F, Ni, Mo,……. Dust ≤ 10 mg/Nm3 Air Pollution Cl, F, Hg

Triple Ten

CHANGE OF REQUIRED COAL QUALITYCHANGE OF REQUIRED COAL QUALITY

√ At Present √ In The Future

Customer Needs Customer Needs Decrease of fuel cost Decrease of fuel cost Expansion of supplying country New environ mental regulation

Required Coal Quality Required Coal Quality Low sulfur and nitrogen Low rank coal High volatile matter Low Na, Ca Non-trouble handling Low Cl, F, Trace elements(Se….)

Combustion Process Combustion Process Pulverized coal combustion PFBC Fluidized bed combustion IGCC etc