PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

STUDY ESTIMATE DISTRIBUTION VARIABILITY OF TOTALMOISTURE IN SEAM COAL USE METHOD OF GPR

Eddy Ibrahim, Lilik Hendrajaya, Gunawan Handayani, Umar Fauzi, Syaiful Islam

INTRODUCTION

This article depict development of technique ofGPR for the measurement of total moisturecontent at coal either through temporal andspasial. Measurement technique the developed istechnique of reflection profiling acquisition bydetermining orientation both of antennaunshielded to yield the polarization ofpropagation perpendicular to bedding plane ofseam coal and place direct both of antennaabove outcrop coal ( figure 1) at same of rank ofcoal which is definition with path length 6.05 m( figure 2) while at outcrop coal with differentof rank of coal by lateral with path length is 3.12m ( figure 3) used by geometry height ofantennas is 0,1 λ ( figure 3 a).

Usage of this technique with frequency ofantenna 100 MHZ where the analysis of usingattribute interval have succeeded determined oftotal moisture content in seam coal at samenessrank of coal where by lateral zone 1 havingcompared to higher total moisture content ofzone 2 due to result of analysis of proximate (laboratory test) by channel sampling ( figure 4, 5). To result of clear process that quantitativelydue to amplitude value of zone 2 the magnitudeintensity storey level of compared to higher ofzone 1 where the value show highly lower totalmoisture content of seam coal by lateral ( figure6 ). While from attribute interval to entire tracefocussed at seam coal for time window ( 4.2 ns- 22.5 ns) can more show total moisture contentlateral variability of seam coal and according toafter validated with result testing of laboratory (analyse of proximate) (figure 7 and 7a). While toclarify boundary of lateral difference of thephysical used by phase spectrum analysis wherevalue phase angular of average vertically toentire trace focussed at seam coal for timewindow ( 4.2 ns - 22.5 ns) hence earning seenclear of boundary area of lateral between coal of

high total moisture content with coal of totalmoisture content low where lower right side thephase angular value of expressing highamplitude value while the boundary area ofexpressed by the happening of phase inversion (figure 8 and 8a)

For the determined of seam coal which bylateral differ rank of coal also succeed to beconducted by using frequency of antenna 200MHZ where because of this traverse line do notbe conducted by analysis of proximate ( test oflaboratory) hence boundary information of rankof coal obtained from PTBA and data drillclosest ( figure 9 ). As for process result earnseen that ( figure 10) visually still difficultdifferentiate between coal of antharacite ( leftside) from trace 1 - 50 and coal of dry coal (right side) from trace 51 - 104. Becauseamplitude intensity and pattern either throughlateral and vertical cannot quantified directly,more than anything else phase angle able to beused for determined of seam coal boundary bylateral. To overcome this problem of usageattribute interval in the reality can differentiateexpressly due to measurement of peak ofamplitude value at coal of anthracite ( trace 1 -50) is 726,53602 DN happened at trace 11 whileat coal of dry coal ( trace 51 - 104) peak of valueof is 380,74705 DN at trace 56 and 598,15242DN at trace 90 (figure 11). Thus can beconcluded by that because of peak of valueyielded amplitude is result of from level averageassess per trace and per sample hence can clarifythat total moisture content for the coal of loweranthracite far than coal of Dry coal. While todetermine boundary area by lateral between bothrank of coal earn determined by using phaseangle value where frontier both of rank of coal attrace to 52 with phase angle value - 1.4012radian of trace to 53 with phase angle value1,15244 radian ( figure 12).

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

REFERENCE

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SEG meeting, Houston, USA, ExpandedAbstracts, 540-543.

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PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

Figure 1. Mode of acquisition of reflection profiling for frequency antenna 100 MHz direct above outcrop coal

coal

I

Figure 2 . : Outcrop coal physical model measured. This coal seam by lateral at the rank of coal is sameness. That is bituminuous coal( seam B2)

Figure 3. : Outcrop coal physical model with path This seam coal by lateral is difference of

Antracite

Line boundacoal) (from P

Indicatorboundary

nterburden

length of 3.12 M rank of coal

Dry coal

ry (rank ofTBA)

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

.

Figure 4. : Schematic of acquisition of channel sampling

Figure 3a. : Mode of acquisition of reflection profiling at path length 3.12 M Frequency of antenna 200 MHz with height 0,1 λ above outcrop

coal.

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

High

Low

Zona 1 Zona 2

Figure 5.: Profile result of analysis of proximate from channel sampling ‘ direction of horizontal expressed position take channel sampling and direction of vertical is thick of coal seam and scale bar expressing obstetrical gradation of total moisture in coal seam

Figure 6.: Profile result of process at physical model outcrop coal with path length 6.05 M

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

Figure 7 :

Figure 7a : .

. Graph of average amplitude value by vertical to entire trace at outcrop coal model with path length 6.05 M

Graph of peak of amplitude values per trace at outcrop coal model with path length is 6.05 m

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

Figure 8.: Graph of average phase angle values by vertical to entire trace at outcrop coal model with path length is 6.05 M

Figure 8a : Graph of peak of phase angle values per trace at outcrop coal model with path length is 6.05 m

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

Figure 10 : Profile result of process use frequency of antenna 200 MHz At outcrop coal model with path length is 3.12 M

Figure 9 : Data information of lithology at mine Air Laya Where Outcrop coal model with path length 3.12m The model is lay in seam C.

Seam coalmeasured

Antracite Dry coal

PROCEEDINGS OF JOINT CONVENTION JAKARTA 2003The 32nd IAGI and The 28th HAGI Annual Convention and Exhibition

Figure . 11 : Average of amplitude values by vertical to entire trace ( trace 1 – 104) at seam coal zone with path length is 3.12 m by using frequency of antenna is 200 MHz

Figure . 12 : Average of phase angle values by vertical to entire trace ( trace 1 – 104) at seam coal zone with path length is 3.12 M by using frequency of antenna 200 MHz