Kuliah 1 Geologi Batubara

8/18/2019 Kuliah 1 Geologi Batubara

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GEOLOGI BATUBARA

2005


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Geologi batubara

exinite

vitrinite

inertinite

Polished setion o! bitu"inous oal#

http://www.newcastle.edu.au/discipline/geology/research/cfkd/macerals.htmhttp://www.newcastle.edu.au/discipline/geology/research/cfkd/undp.htmhttp://www.newcastle.edu.au/discipline/geology/research/cfkd/macerals.htmhttp://www.newcastle.edu.au/discipline/geology/research/cfkd/macerals.htmhttp://www.newcastle.edu.au/discipline/geology/research/cfkd/undp.htmhttp://www.newcastle.edu.au/discipline/geology/research/cfkd/macerals.htm


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Geologi batubaraTwo broad categories of coal

Coal is an organic sediment consisting of a complex mixture ofsubstances.

humic

More common and originates from peat deposits consisting mostly of

organic debris deposited in situ (autochthonous).

sapropelic Derived from redeposited (allochthonous) resistant plant fragments

such as spores or aquatic plants. The sapropelic coals can be further

subdivided into$ Cannel coal is made up principally of uniformly si!ed plant

fragments eg spores

$boghead coal Consists mainly of alginite (a coal maceral derivedfrom algae).

"eat is formed from the deposition of organic material with a restricted

supply of oxygen. "eat forming environments are #nown generally as

$mires$.


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Geologi batubara

Mires may be classified as limnic or paralic

Parali de%osits i"%l& that there 'as a h&drologial onnetion 'ith thesea at the ti"e o! %eat de%osition# (ires "a& be !ound along oastallo'lands) as ba* barrier lagoons+ estuaries and deltas#

Peat !or"ing environ"ents isolated !ro" the sea+ !or exa"%le slo'l&

subsiding basins %rodue li"ni oal de%osits#The t&%e o! original %lant in%ut+ the availabilit& o! nutrients+ li"ati

onditions+ the level o! the 'ater table+ the %, and Eh onditions allhel% to deter"ine the type of peat that is formed# Ever& %art o! theeos&ste" o! the %eatland or "ire "a& be re%resented in the %eat+inluding the large trees+ herbaeous shrubs+ grasses+ a-uati

%lants and the "iro.organis"s that brea* do'n the organi"aterial#

/or a oal to be develo%ed+ the %eat has to be buried and %reserved#The %roess that onverts %eat to oal is alled coalification# Thedegree o! oali!iation 'hih has ta*en %lae deter"ines the rank o!the oal#

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Geologi batubara

Coalification

The trans!or"ation o! %lant "aterial intooal ta*es %lae in t'o stages+

biochemical degradation and

physico-chemical degradation#



7/42

Geologi batubara

%iochemical degradation involves he"ial deo"%osition o! botanial "atter assisted b&organis"s# In tro%ial environ"ents+ this %roess "a& be !aster+ sine the 'ar" "oist onditionsare ideal !or the organis"s that assist in this %roess suh as bateria and !ungi# ,o'ever %lantgro'th is also "ore ra%id and so the inreased rate o! deo"%osition "a& be balaned b& %lantgro'th# In tro%ial onditions high rates o! eva%oration need to be ou%led 'ith high %rei%itationto "aintain %lant gro'th and %eat au"ulation#

In ooler li"ates the gro'th rate o! vegetation "a& be &lial in nature and slo'er sine the

seasonal variation in onditions is greater# The onditions are less ideal !or !ungi and bateria sothe slo'er gro'th rate is "athed b& a slo'er rate o! biohe"ial degradation#

,u"i!iation a!!ets the so!t ontents o! the %lants ells be!ore the ell 'alls+ 'hih onsist o!ellulose+ he"iellulose and lignin 'hih is the "ost resistant o"%ound#

,u"i!iation begins 'ith the oxidation o! %lant "atter and atta* b& aerobi organis"s suh as !ungi+insets and aerobi bateria# ,&droarbons are extrated !ro" the tissue and the "aterial le!tbehind is relativel& enrihed in ox&gen and arbon# e"i!usinite+ an inertinite "aeral "a& be!or"ed in this "anner#

1arious hu"i substanes are !or"ed at this ti"e+ these are aidi in nature# I! this ontinues the

%lant "aterial 'ill be o"%letel& degraded into arbon dioxide and 'ater# hen the %lant "aterialor degraded %lant "aterial is buried belo' the ground 'ater table aerobi organis"s andoxidation an no longer atta* the "aterial# Anaerobi bateria "a& still deo"%ose the %lant"atter until it reahes a de%th or onditions unsuitable !or these organis"s# Anaerobi bateriautilise the ox&gen in the %lant "atter+ so all "oleules "a& be atta*ed even the "ore resistanto"%ounds# ,o'ever the so!ter tissue "a& be "ore ra%idl& a!!eted#

Biohe"ial oali!iation ends at the ran* o! sub.bitu"inous oal+ 'hen hu"i substanes have%ol&"erised#


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Geologi batubara

"hysico&chemical coalification 'hih !ollo's is ausedb& onditions o! burial# The overburden 'hih isde%osited+ the heat !lo's in the earth3s rust and tetoniheat and %ressure hange the he"istr& and struture o!

the altered organi "aterial# The sa"e onditions area%%lied to all the "aerals#

ater is s-uee4ed out and %ore si4e is redued as%ressure inreases and ox&gen and h&drogen arereleased during ther"al ra*ing# ater and arbon

dioxide are the !irst %roduts released#hen ran* reahes "ediu" volatile bitu"inous oal

de"ethanation begins#



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Geologi batubara

Concept of Coal 'an#

The ran* o! a oal re!ers to the degree o!oali!iation endured b& the organi

"atter# It is esti"ated b& "easuring the"oisture ontent+ s%ei!i energ&+re!letane o! vitrinite or volatile "atter

these are *no'n as ran* %ara"eters6#ee Table 7 !or details o! the di!!erent ran*stages#

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Geologi batubara

Table 7# /ro" 8iessel 79926 indiates the

di!!erene in ran* %ara"eter 'ith inrease

in ran*#


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Geologi batubaraClassification of organo&petrographic constituents

:oal is used industriall& !or a nu"ber o! %ur%oses+ sine it is a highl& variable%rodut its use is de%endent on the individual %ro%erties o! a sea" or %artthereo!# :oal is as variable as the onditions in the "ire+ during and a!ter%eat au"ulation# To ao""odate this a nu"ber o! classification systems have been develo%ed so that the oal is used a%%ro%riatel The !our "osto""onl& used s&ste"s are the ; International Organisation !or tandardisation IO6 ; A"erian oiet& !or Testing (aterials AT(6 ; Australian tandard A6 ; British tandards Institution BI6 lassi!iations#

:oal bene!iiation engages "ethods to i"%rove oal -ualit& !or a %artiularindustrial a%%liation+ i! the oal needs to be altered be!ore use # The "ost

i"%ortant o! these inlude+ 'ashing to re"ove ash and desul!urisation#Petrogra%h& is the "iroso%i stud& and desri%tion o! oal and ro*s# The

%etrogra%h& o! oal is i"%ortant sine it a!!ets the %h&sial and he"ialnature o! the oal# :oal rushing+ grinding+ handling+ 'ashabilit&+gasi!iation+ li-ue!ation o"bustion and arbonisation are a!!eted b& the%etrogra%h& o! the oal#

:oal 3t&%e3 re!ers to the %etrogra%hi onstituents in oal#



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Geologi batubara

Macerals

The s"allest "iroso%iall& reognisable entities in oal are alled macerals+ the& are analogous to "inerals in ro*s# ,o'ever the&di!!er sine "inerals have an ho"ogeneous he"istr& and an orderl&

internal struture+ 'hile oal "aerals onsist o! a "ixture o!o"%ounds#

The he"ial and %h&sial %ro%erties o! "aerals var& 'ith oal ran*#:oal "aerals are distinguished b&< ; their o%tial harateristis o! olour ; relie! o! the %olished sur!ae

; "or%holog& ; re!letane and !luoresene

(aerals di!!er beause the& re%resent di!!erent %arts o! the original%lant "aterial and "iro.organis"s that ontributed to the %eat# The mode of preservation+ that is 'hether or not the organi !rag"ents'ere oxidised be!ore being %reserved+ is also onsidered in thelassi!iation o! "aerals#

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Geologi batubara

Inertodetrinite set in a

vitrinite ground"ass# Inertodetrinite set in vitrinite

ground"ass# Re!leted light+

=>0 oil ob?etive#2 20* ?%egs6

http://www.newcastle.edu.au/discipline/geology/research/cfkd/mac2.jpg


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Geologi batubara

$ There are three maceral groups vitrinite+inertinite and li%tinite exinite6# These are allsubdivided into "aeral subgrou%s and"aerals# everal s&ste"s o! no"enlature exist 'orld 'ide# The Australian [email protected] is "odi!ied !ro" the s&ste"used b& the International :o""ittee !or :oaland Organi Petrolog&+ 'hih is ontinuall&revie'ing their ter"inolog& and lassi!iation#Table 2 gives a lassi!iation based on the

Australian standard s&ste"#

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Geologi batubara

The li%tinite grou% is relativel& enrihed in h&drogen o"%ared 'ith theother t'o grou%s+ inertinites have a greater arbon ontent andvitrinites have an inter"ediate he"istr As ran* inreases thedi!!erenes in the he"istr& bet'een the grou%s di"inishes#

The vitrinite grou% generall& re%resents the 'ood& %lant "aterial eg#

ste"s + trun*s+ roots and branhes# Li%tinite inludes the "oreresistant %arts o! %lants li*e s%ores+ utiles and resins and inertiniteis "aterial that has been oxidised %rior to oali!iation#

1itrinite and inertinite are subdivided into "aeral subgrou%sde%ending on si4e and the degree o! geli!iation# Three %re!ixes areused to divide the "aerals into "aeral subgrou%s# Telo- and

detro- di!!erentiate bet'een the si4e o! the individual %artiles and gelo- "eans the "aterial has been geli!ied#



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Geologi batubara

Table 2< :lassi!iation o! "aerals into

subgrou%s and grou%s+ based on the

Australian tandard s&ste" o!

no"enlature A25.796CD re!ers to

bro'n oal "aerals


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Geologi batubara

1itrinite in bitu"inous oal is dar* to light gre& inolour+ de%ending on the ran*# Telovitrinitere%resents intat !rag"ents o! %lant "atter+ theoriginal %lant ell struture "a& be visible in this

"aeral subgrou%# 8etrovitrinite results !ro"s"aller !rag"ents "ust be F20" in greatestdi"ension [email protected] that o!ten !or" aground"ass !or other "aerals# Geli!ied"aterial %rodued be!ore or during oali!iationbeo"es gelovitrinite 'hih is relativel&uno""on# The vitrinite "aeral grou% isdesirable tehnologiall



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Geologi batubara

The inertinite "aeral grou% originates !ro" the sa"e "aterial as thevitrinite grou% ho'ever the oxidation endured be!ore oali!iationhas hanged its o%tial %ro%erties and he"istr It is "uh lighteroloured var&ing !ro" light gre&+ to 'hite+ to &ello'6 in o"%arison'ith vitrinite# :ell struture is visible in telo.inertinites 'hih aresubdivided aording to the degree o! oxidation# These "aerals"a& exhibit a high degree o! relie!# The oxidation "a& haveourred at an& ti"e be!ore %eat %reservation# /orest !ires 'hihoxidise 'ood+ an our during %eat au"ulation+ burnt leaves and'ood haroal6 result in the !or"ation o! the "aeral !usinite# ineit has a high arbon ontent to start 'ith the o"%osition o! this"aeral does not var& 'ith ran* Plant "aterial "a& have alread&

started to geli!& and brea* do'n be!ore oxidation+ this oxidised gelan !or" the "aeral "arinite#



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Geologi batubara

Inertinite+ "arinite hori4ons+

se"i!usiniteH!usinite !rag"ents#

In !luoresent "ode+ inertinite bodies

dis%la& var&ing degrees o! !luoresene

intensit&+ 'ith "arinite hori4ons

"arginall& "ore intense than

se"i!usinite and !usinite !rag"ents# It

has been !ound that !luoresent inertinite

!uses during arbonisation#2x20* ?%egs6

http://www.newcastle.edu.au/discipline/geology/research/cfkd/mac1.jpg


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Geologi batubara

The !inal "aeral grou% is li%tinite+ these "aerals inludethe %arts o! %lants that beause o! their he"istr& are"ore resistant to %h&sial and he"ial degradation#uantitativel& this "aeral grou% is usuall& "uh lesso""on+ than the other t'o "aeral grou%s# Abovea%%roxi"atel& 7#25J "ean rando" vitrinite re!letaneli%tinite is indistinguishable !ro" vitrinite# %ores+ utiles!ound on the sur!ae o! leaves and ste"s6+ 'axes andresin are inluded in this grou%+ as is alginite 'hih is there"ains o! algae and rarer substanes that "a& onl& be

deteted using !luoresene "iroso% In general thisgrou% has a gre& to bro'nish a%%earane 'ith distintive"or%holog& and is highl& !luoresent 'hen irradiated'ith short 'ave ultra violet or blue6 light#


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Geologi batubara

In !luoresent "ode+ exinite li%tinite6

bodies !luorese "ar*edl Inertinite

hori4ons dis%la& "ini"al !luoresene#

/luoresent light# >0x dr& ob?etive#

72* ?%eg6#


22/42

Geologi batubara

Using a "iroso%e individual s%eies o! %lantsand "iro.organis"s that ontributed to the %eatde%osit have been identi!ied+ b& stud&ing thet&%e o! s%ores and %ollen+ %lant tissue or !ungal

s%ores# This an then be used to orrelate so"esea"s or sea" s%lits+ gain a rough esti"ate o!the age o! the de%osit or %rovide so"e insightinto the environ"ent o! de%osition# Kno'ing theenviron"ent o! de%osition "a& be use!ul to%redit hanges in oal -ualit /or exa"%leantii%ating high sul!ur and nitrogen values andhanges in ash ontent#


23/42

Geologi batubara

The -uantit& o! eah "aeral grou% varies both

bet'een and 'ithin oal sea"s# Tehnologiall&

vitrinite is usuall& the "ost desirable "aeral

grou%+ sine it ontains "ore h&drogen andox&gen+ but these ele"ents derease 'ith

inreasing ran*# The na"e inertinite is a

"isno"er as it is not all inert# The lo'er

re!leting inertinite 'ithin a sa"%le has been!ound to be reative during arbonisation

8iessel ol!!./isher + 79M6#


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Geologi batubara

(aerals di!!er in their s%ei!i gravit&+ this

an be used to se%arate the oal !ro" the

"ineral "atter in rushed sa"%les and

also to se%arate out so"e inertinite eg#!or oal li-ue!ation6# Li%tinite "aerals

are the lightest grou% !ollo'ed b& vitrinite

then inertinite# /usinite the "ost arbonrih inertinite has a s%ei!i gravit& F7#5#


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Geologi batubara

The ,ardgrove grindabilit& o! a sa"%le is

also a !untion o! the %etrogra%hi

o"%osition+ !usinite is the easiest to

grind+ vitrinite is the next so!test 'hileli%tinite "aerals are the hardest to grind

beause o! their 'ax& nature Tsai 7926#


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Geologi batubara

MicrolithotypesInreasing in sale the "aerals o! oal !or"

"irolithot&%es+ these are bands F50" 'ide# Thereare three "ain lasses o! "irolithot&%es those thatontain one t&%e o! "aeral "ono"aerali6+ t'o t&%eso! "aeral both 'ith a %ro%ortion F5J bi"aerali6 andF5J o! all three "aeral grou%s tri"aerali6#

(irolithot&%e o"%osition sho'n in Table @ ada%ted !ro"tah et al# 7926# The arrange"ent o! "irolithot&%es

is i"%ortant tehnologiall& beause o! loalisedreations during o"bustion+ arbonisation+ li-ue!ationand gasi!iation# /or exa"%le vitrinertite sine it ontainsso"e inertinite is "ore li*el& to %rodue a stronger o*e#


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Geologi batubara

Table @ < :lassi!iation and o"%osition o!

"irolithot&%es+ !ound in oal ada%ted

!ro" tah et al# 7926


28/42

Geologi batubaraithotypes

In hand s%ei"en oal is o!ten banded+ re!leting hange in "aterialand onditions in the "ire# These bands are ter"ed lithot&%es andthere are several s&ste"s o! lassi!iation aording to ran* and%re!erene#

:lassi!iation o! bro'n oals "a& be based on olour+ texture+desiation %attern+ strength and degree o! geli!iation#

The lassi!iation o! bla* oal lithot&%es is given in Table > !ro"8iessel 79926# The %ro%erties o! lustre+ t&%e o! !rature+ %ro%ortiono! banding and "ineral "atter ontent are used to distinguish theoal lithot&%e# Eah individual band "ust be greater than 5"" in'idth#

The ter"s vitrain+ larain+ durain and !usain re!er to the lassi!iation o!to%es 79796 'hih has been extended to a%%l& to a 'ider range o!oals# In %ratie during logging o! ore or a oal !ae+ an esti"ateis "ade o! the %erentage o! oal brightness + this is use!ul as aguide to the o"%osition o! the oal and tehnologial a%%liation#The brightness log "a& also be used in deter"ining roo! and !loorli"its o! "ining #


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Geologi batubara

'outine nalyses


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Maceral nalysis

A "aeral anal&sis is arried out on %re%ared %olishedgrain "ounts or %ellets6+ the oal is rushed ande"bedded in a "ounting "ediu" and the sur!ae is

%olished !or "iroso% The anal&sis usuall& involvesounting a thousand %oints on a grain "ount 'hih isovered b& evenl& s%aed traverses using a "ehanialstage# Eah ti"e the entre o! the i"age !alls on a"aeral+ that "aeral is entered into a %oint ounter#

The result is a volu"e %erentage o! eah o! thedi!!erent "aerals %resent in the sa"%le#

Geologi batubara


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*itrinite 'eflectance

/or bitu"inous or bla* oals the "ost o""onl& usedran* %ara"eter is vitrinite re!letane+ 'hih is "easuredroutinel tandards are !ollo'ed !or the %re%aration o!sa"%les# The sa"%le is rushed to a %artiular si4e thene"bedded in a "ounting "ediu"+ the sur!ae is ut and%olished and vie'ed under a "iroso%e using re!letedlight light is direted onto the sur!ae o! the %olishedsur!ae and re!leted ba* to the e&e %iee and"easuring devie6# Re!letane is "easured on the

"aeral telovitrinite and standards indiate the "ethodto be used) International IOM>0> 79> %art 56+

Australian tandard A 2>.7996 and AT( 82M9.6#

Geologi batubara


32/42

Geologi batubara

This gra%h illustrates the

inreasing+ then

dereasing relative!luoresene intensit&

'ith inreasing oal

ran* Ro6# The

"axiu"u" o!

!luoresene intensit&is at 7#7J Ro "ax#


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Table >< The lassi!iation o! bla* oal

lithot&%es !ro" 8iessel 79926#

Geologi batubara


34/42

"roximate nalysis

The degree o! %h&sio.he"ial oali!iation o! a oal is indiated in a%roxi"ate anal&sis# There are international standards !or the%roedure o! the %roxi"ate anal&sis) British tandard B 707+ %art@+ 79M@6+ Australian tandard A 70@#@.7996 AT( 8@[email protected]#

A sa"%le is heated to a%%roxi"atel& 900o: so that all the ox&gen+h&drogen+ sul!ur and nitrogen are released as volatile "atter 1(6#The a"ount o! residual har re"aining is inversel& %ro%ortional tothe volatile "atter and is alled the a"ount o! !ixed arbon /:6#The "oisture o! the sa"%le is also "easured in this anal&sis b&"easuring the di!!erene in "ass o! the sa"%le be!ore and a!terheating# The !inal variable "easured in this anal&sis the ash

ontent# Ash is deter"ined b& heating oal in a !urnae at a%artiular rate u% to 75o: in the Australian and British tandardsand M50o: in the AT( %roedure#

Geologi batubara


35/42

+ltimate nalysis

An ulti"ate anal&sis is %er!or"ed on oal sa"%les 'hen !urther in!or"ation is re-uired#The !ollo'ing standards outline the %roedure to be ado%ted !or the deter"ination o!an ulti"ate anal&sis) British tandard B 707+ %art + 79MM6+ Australian tandardA 70@#6 and AT( [email protected]# The -uantit& o! the %rini%al ele"ents in oal)arbon+ h&drogen+ ox&gen and sul!ur+ are deter"ined# Usuall& the results o! a%roxi"ate and ulti"ate anal&sis are enough to indiate ho' the oal "a& be utilised#ul!ur and nitrogen an be %ollutants 'hen the oal is o"busted or arbonised# Alternativel& so"e sul!ur "a& be use!ul as a atal&st during oal li-ue!ation#

$ :arbon and h&drogen are !ound in oal as h&droarbons# The -uantit& o! these isdeter"ined b& heating an air dried sa"%le in a strea" o! ox&gen and olleting the:O2 and ,2O %rodued#

$ Nitrogen is deter"ined using the K?eldahl "ethod# The nitrogen is onverted toa""oniu" sul!ate in sul!uri aid# Titration is then used to !ind the a"ount o!a""oniu" sul!ate#

$ /our -uantities are usuall& -uoted !or the sul!ur ontent# ; Total sul!ur inludes the three !or"s o! sul!ur "easured# ; Organi sul!ur is that 'hih is bound in organi "oleules h&droarbons6 and originates

!ro" the sul!ur in the %lant "atter that ontributed to the %eat de%osit# ; ul!ide sul!ur is that usuall& !ound in the !or" o! %&rite and "arasite and is "ost easil&

re"oved b& rushing+ !ollo'ed b& 'ashing or !loat sin* "ethods#

$ Ox&gen is usuall& alulated !ro" the di!!erene o! the other ele"ents !ro" 700J

Geologi batubara


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Mineral Matter

(ineral "atter is di!!erent to the ash -uantit& o! a %roxi"ate anal&sis# (ineral"atter is the -uantit& o! "inerals observed in a grain "ount and is usuall&inluded in a "aeral anal&sis# Ash is a s"aller -uantit& sine it is !ound b&heating the sa"%le and the h&drous "inerals are altered in the %roess#

(inerals "a& be 'ashed into the "ire during %eat de%osition+ or "a& result

!ro" air !alls due to volani ativit Other "inerals %rei%itate out o!ground 'ater solution# 8issolved "inerals "a& also our in the sur!ae and%ore 'ater o! the sa"%le# This t&%e o! "ineral "atter is re!erred to as $adventitious$#

Plants the"selves ontain inorgani o"%ounds and organo."etallio"%lexes+ that an be added to the %eat# This t&%e o! "ineral "atter !or"s $inherent ash3#

(ineral "atter "a& our in thin bands+ !ill ra*s or !issures or be inti"atel&assoiated 'ith the oal "atrix# :ell lu"ens o!ten ontain "inerals or"ineral "atter "a& re%lae the ell struture eg# siderite and %&rite# It "a&also our !inel& dis%ersed 'ithin the oal "atrix# 8isrete bands o! "ineral"atter and in!illings are "ore easil& re"oved during oal 'ashing#

Geologi batubara


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Table 5< /ro" tah et al# (inerals that are

!ound in oal#

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(ineral "atter in oal is ino"bustible and so is le!t as aresidue !ro" tehnologial a%%liations# (ineral "attera!!ets the oal %roessing and handling# ,ard "ineralsinrease the 'ear and tear on e-ui%"ent duringhandling and rushing# The -uantit& o! ash and its

o"%osition is i"%ortant to deter"ine the "ethod o! itsre"oval+ either as a dr& ash or a slag# The o"%ositiono! oal ash an a!!et the %rodut !or"ed# In the ase o!o*ing+ the -ualitit& o! the steel %rodued is a!!eted b&the ele"ents in the ash eg# %hos%horous is

undesirable6# Other ele"ents are %ollutants eg# sul!ur#Ten ele"ents are routinel& deter"ined and areex%ressed as oxides+ thes are iO2+ Al2O@+ :aO+ Na2O+K2O+ /e2O@+ TiO2+ (gO +P2O@ and O@#

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The "ost abundant "inerals in oal are la&s+ these are variable intheir he"istr 8o"inant "inerals inlude *aolinite+ illite"ont"orillonite and illite."ont"orillonite "ixed la&er la&s# Bands o!la& "inerals are use!ul as "ar*er beds to orrelate sea"s aross aoal!ield# :la&s 'hih have s'elling %ro%erties suh as those in the"ont"orillonite grou%+ ex%and in ontat 'ith 'ater# This redues

strength and an be ha4ardous during "ining# :la& "inerals areonverted to silia and alu"ina during ashing#

:arbonates are the next "ost o""on "inerals# The "ain "ineralsare siderite+ an*erite + alite and dolo"ite# These deo"%ose togive "etal oxides and arbon dioxide#

ul%hides and oxides are o""onl& !ound in oal# Table 5# !ro" tah

et al#+ 7926 lists "inerals !ound identi!ied in oal and theira%%roxi"ate abundane#

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sh ,usion

The te"%erature at 'hih the ash "eltsdeter"ines 'hether ash 'ill be re"oved

dr& or as a slag during o"bustion# I! theash !usion te"%erature is lo'er than!urnae te"%erature + the ash "elts and isre"oved as a slag# ,o'ever the visosit&o! the slag is also de%endent on the asho"%osition#

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'eferences

Baile& #G#799@6 Training :ourse o! :oal Prodution+ Utilisation andEnviron"ental %rotetion# Baile& #G#799@6 Training :ourse o! :oalProdution+ Utilisation and Environ"ental %rotetion# UN8PHPA:E.E

8iessel :#/#K# 79926 :oal. bearing de%ositional &ste"s# %ringer.

1erlag#8iessel :#/#K# ol!!./isher E# 79M6 :oal and :o*e %etrogra%hiinvestigations into the !usibilit& o! :arboni!erous and Per"ian:o*ing :oals# International ournal o! :oal Geolog& 9< M.70#

tah E#+ (a*o's*& (.Th#+ Teih" ller (#+ Ta&lor G#,#+ :handra 8#+Teih" ller R# 7926 tah3s Textboo* o! :oal Petrolog @rd

edition# Gerbr der Bortraeger+ Berlin+ tuttgart#

Tsai #:# 7926 :oal iene and Tehnolog& 2. /unda"entals o! oalBene!iiation and Utilisation# Elsevier ienti!i Publishing :o#

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Geologi batubara

Kuliah 1 Geologi Batubara

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