PROCEEDING

FIRST ANNUAL

UNIVERSITAS MALAHA Y A TI

ON GREEN TECHNOLOGY AND

ENGINEERING

On July 25- 26t11, 2007

1. 2. 3. 4. 5. 6. 7. 8. 9.

Editor:

Drs. P. Nasoetion, M.Si Dewi Sartika, S.TP, M.Pd, M.Si Jr. Yan Juansyah, DEA Emy Khikmawati, S.T Eka Purnama Sari, S.Si, M.Si Rina Febrina, S.T Eleny Andarna, S.T Gustya Nofriady N. Nelna Atiza

10. Sugianto

UNIVERSITAS MALAHA Y ATI BANDAR LAMPUNG

2007 ..

FOREWORD

The International Seminar on Green Technology and Engineering 2007 (ISGTE 2007) Faculty of Engineering, Universitas Malahayati was conducted on 25-26 July 2007. The Seminar was organized by Faculty of Engineering and collaborated with International Islamic University Malaysia (IIUM) and University Putra Malaysia (UPM).

The participants of the seminar are about 200 participants come from more than 20 higher institutions, among others: Unhas, ITS, UI, Tri Sakti, ITB, Unila, Unsri, Unibraw, UPM (University Putra Malaysia), IIUM (International Islamic University Malaysia), UTM University Technology Malaysia), and others, which reflect the importance of Green Technology and Engineering. The concept of sustainable development based on the environmental firmament nowadays has become central issues in many development as well as developed countries. These issues are very important and the topic of this issue can create awareness of the societies to involve in the development of their country toward the sustainable development.

The seminar provide platform for researchers, engineers and academician to meet and share ideas, achievement as well as experiences through the presentation of papers and discussion. These events are important to promote and encourage the application of new techniques to practitioners as well as enhancing the knowledge of engineers with the current requirements of analysis, design and construction of any engineering concept. Seminar also functions as platform to recommend any appropriate remedial action for the ·implementation and enforcement of policies related to environmental engineering fields. Furthermore, this seminar provides opportunities to market faculties' expertise in the field environmental engineering, civil engineering, structural engineering, mechanical engineering and so on.

On behalf of Steering Committee, we would like to express our deepest gratitude to the Foundation Alih Technology, Rector Universitas Malahayati, International Advisory Board members, and also to all participants. We are also grateful to all organizing committee and all the reviewers, without whose efforts such a high standard for the seminar could not have been attained. We would like to express our deepest gratitude to the Faculty of Engineering Universitas Malahayati for conducted such seminar. This is the first International Seminar for the Faculty and we expect that this is will become annual activity for the Faculty of Engineering.

Bandar Lampung, 25 July 2007

Agung Efriyo Hadi The Organizing Chairman

FIRST ANNUAL UNIVERSITAS MALAHA Y A TI INTERNATIONAL SEMINAR

ON GREEN TECHNOLOGY AND ENGINEERING

Chair person Vice Chairperson Secretary Treasurer Special Events

On July 25- 26th, 2007

' I

(Steering Committee)

Dr. Agus Geter Sucipto Assoc. Prof. Dr. Riza Muhida Assoc. Prof. Dr. Wahyudi Drs. P. Nasoetion, M.Si Dr. Hardoyo, M.Eng

Dr. Asnawi Lubis Dr. Eng. Admi Syarief Assoc. Prof. Dr. Robiah Yunus Agung E. Hadi, M.Sc Prof. Dr. Ismail bin Mohd. Assoc. Prof. Dr. Ir. Mohd. Sapuan B. Sahit

(Organizing Committee)

Ir. Drs. Agung Efriyo Hadi,M.Sc Drs. P. Nasoetion, M.Si Rina Febrina, S.T Eka Purnama Sari, S.Si, M.Si Dewi Sartika, S.TP, M.Pd, M.Si Fither Romilado, S.T

Facility and Accomodation Consumption

Ir. Yan Juansyah, DEA Emy Khikmawati, S.T

Documentation and Publication Tumpal Ojahan R, S.T

HALAMAN JUDUL

FOREWORD

CONTENT

KEYNOTSPEAKER

CONTENT

11

Genetic Algorithm And Engineering Optimizations In Logistic

Green Nanotechnology Using SEM And AFM 11

Green Energy From Biomass Waste (Energi Hijau Dari Limbah Biomasa) 18

Evaluasi Green Productivity Pada Proses Frosting Pada Perusahaan Gelas Lampu Di Surabaya 25

Thin Film Solar Cells: Prospect And Challenges 38

Alternative Diesel Fuel And Synthetic Lubricant From Palm Oil 47

PAPER

TEKNIK MESIN

The Influence Of Intermediate Tangent On Flexibility And Stress Intensification Factors Of Shaped Steel Piping Elbows 58

Waste To Energy In Porns Biomas Power Plans In Kota Pinang Cluster North Swnatra- .Indonesia 66

Application Of Taguchi Method In The Optimization Of Turning Parameters For Surface Roughness 73

Integrated Gasification Combined Cycle (Igcc) A Clean Coal~ · Fueled Power Plant Technology 81

.. Simulation Of Thermal Efficiency Of Steam Power Plant Bukit Asam By Using Newton Raphson Method 90

Study Of Two High Starch Cassava Lines And Two Low Starch Cassava Lines As Raw Materials For Bioethanol ]n The Laboratory Scale ·· 1 0 1

Study Of Waste Of New Energy Bioethanol Use Cassava And Molasses As Raw Materials 109

11

lntemational Seminar On Green Teclmology and Engineering (ISGTE) MALAHA YATI UNIVERSITY

SIMULATION OF THERMAL EFFICIENCY OF STEAM POWER PLANT BUKlT ASAM BY USING NEWTON RAPHSON METHOD

By:

Hasan Basri

Mechanical Engineering Department, Faculty of Engineering, University ofSriwijaya

Jl. Raya Pal em bang- Prabumulih Km 32, lnderalaya Telp.{07/l) 580739, e-mail: hasan_basri@unsri.ac.id

Abstract

This research intents on increase of thermal efficiency of Steam Power Plant Bukit Asam. Method used is by making simulation in use of Newton Raphson Method The steps are, first make function of mathematical equations of test performance data up to three periods in one year and energy balance equations, second solve mathematical function equations by making simulation program in use of Newton Raphson Method

After simulation has been performed, it is acquired that thermal efficiency increases 4% and electricity production increases by 3.26 MW.

Keywords: Simulation, thermal efficiency, power plant.

1. INTRODUCTION

Based on· data specification of four units (unit 1 to 4) of steam turbine power plants, the assembled electrical power produced by each unit is 65 MW/unit. But according to the field survey of steam turbine power plant unit 4, the performance test result in one year for three periods on January, June and December, shows that electricity production yielded always changes that tends to decrease between 5 to 1 5% of assembled power (3] .

Besides electricity decreasing trend can also be seen from daily electricity production data in a year. There are some factors that influence electricity production decreases, one of them is caused by operation variables of generator system (i.e. in boiler, turbine, generator, condenser, and heater) that always change so they influence the rate of energy system accumulatively that will impact in thermal efficiency and in tum ascendant in unstable electricity production. One of impact which may happen because of unstability of electricity production is lack of

90

electricity supply that causes rotated extinction especially in peak loads [4].

To solve this problem, there are some ways can be done, e.g. replacing old to new power plant or maintaining the existing power plant. Maintenance can be meant as a coherent activity between administration and finance to keep. and or bringing back asset condition (steam power plant units) so it can reach the aim expected. One of them is having high thermal efficiency and production of electricity [5].

In relation to this, therefore thermal efficiency needs to be improved, increasing thermal efficiency will finally increase electricity production. Benefit from simulation in this research is we can modify operation variables within designed capacity limits (design condition), arrange operational condition correction or calibration to arrange improvement in more economical cost, and give opinion contribution in order to increase thermal efficiency and electricity production.

International Seminar On Green Technology and Engineering (ISGTE) MALAHA YATI UNIVERSITY

2. LITERATURE REVIEW

. Based on theoretical study result, it 1s stated that change of electricity production of steam power plant are· caused by some factors, amongst those are fuel consumption and operational ' variable of main component of the steam power plant. Refer to perfonnance test result, it is known that the mass flow rate of fuel in 3 periods is relatively stable for 0, 44 kg/kWh but operational conditions of main components such as temperature, pressure, enthalpy, and mass flow rate are always arbitrary. The changing of these parameters will impact in. changing thennal efficiency . that in turn will impact the electricity production becomes unstable.

There are many methods to make simulation; some of them are Bisection Iteration, Gauss- Seidel, Jacobi, and Newton Raphson method (15] . In order to get better final result from the methods above, we can use Newton Raphson Method [7]. Th~ excellence of Newton Raphson method besides we can get more accurate prediction, it can be used for functions that have either linear or nonlinear variables. ·

The perfonnance of a turbo machine can be described by using graph, the relationship among variables in that ma7hi.ne e.g. flow rate (Q), speed v~natt~n (n) and pressure change (~P) wtll m general give results in mathematical equations [11].

Simulation system is a calculation of operational variables (i.e. pressure, temperature, mass flow rate, etc.) in thennal system for steady state condition. Equations of perfonnance characteristics of components and thennodynamic characteristics of mass a~d energy balance fonn a group of stmultaneous equations of operational variables, thus simulation of thennal system solves the linear or non linear equations.

Thennal system of a steam power plant is a repetitive cycle system, that its energy flow can be analyzed by first law of thennodynamic for energy flow which penetrates in a system as mass and volume control [13]. Application of the first law of thennodynamic for volume control is shown in Figure 1.

r------ v......_r.,....,.,,.,. .. .._.,.,_,, ... ,,,

I ..... ··-.. ·-··· ·-··· ~ .. I r r -:-.1.------------, : ""'·· ,..--;J __ s--- ---------, L __

v, I t •r.--. 1.--.., -. 4'\~ -A: ~ : :.~ -----{:.;- -I;,--, r- -. I

l , '-- -------- -- J r -r=t---'----- -- r:-- -----" I

Figure 1: Energy Flow Penetrates Volume Control

By assuming process is occurred in a steady state condition therefore energy balance for volume control can be written as in equation ( 1 ). This equation can be applied to analyze boiler, turbine, condenser, pump, feed water heater, etc.

Generally working fluid used in steam power plant is water (H20). Rankine cycle is a standard cycle for steam power plant by using liquid-vapor phase (12] which are shown in Figure 2 and 3 below.

Wprocess + QL:m X h = L:mx h ..... (1) in out

. 91

SG

(4)

International Seminar On Green Technology and Engineering (ISGTE) MALAHAYATI UNIVERSITY

(1)

(:Z)

(3)

Figure 2: Ideal Rankine cycle

Where: QA : Heat enter to steam generator (SG) OR :Heat rejected from condensor (C) Wp: Work of pump (P)

Figure 2 shows that superheat steam (I) resulted by steam generator (SG) then enter turbine (T) and results turbine work (WT). Steam resulted from turbine expansion (2) goes to condenser

(C) as saturated liquid (3), this saturated liquid is pumped by pump (P) to steam generator (SG) to be evaporated and then return to (I).

r CP ( 1 )

L---~---------~·· 11

Figure 3: T-S diagram for ideal Rankine cycle

Figure 3 shows that cycle 1 - 2 - 3 - 4 - 1 is superheat Rankine cycle. The process occurred is as follows:

I - 2

2-~

3-4

4 - 1

92

=

=

=

=

Expansion of reversible adiabatic process occurs, commonly the fluid comes from turbine is in two phases. Constant temperature in two phases, heat is rejected out from condenser with constant pressure. Pumping process of reversible adiabatic, saturated liquid from condenser is pumped and the pressure is increased from P3 to P4•

Process of heat added into steam generator.

International Seminar On Green Teclrnology and Engineering (ISGTE) MALA HA YA1'1 UNIJ/ERSITY

3. METHODOLOGY

The simulation program ofthe.rmal efficiency can be described as follows:

8

II

1. The diagram of energy flow of steam power plant Bukit Asam is drawn and and analyzed by the use of Rankine cycle.

5

p

6

Figure 4: Cycle diagram of steam power plant Bukit Asam

Data available in Figure 4 are:

Pt = 87 p4 = 0.4 17a = 98% bar bar p2 = 3 Tt =510 m =4300 bar oc kgls p3 = 0.8 17r= 85% bar

Parameters that will be calculated are:

Pump

Figure 5: Energy Balance of Pump

Wr; qA; q8; qc; rnt; m2; m3; m4;

'lk; 17 P; h6; h1; hs; h9; hto; T8; T1;

Tg; 'lthermal

2. The Mathematical Equation By Use Of Energy Balance In Each Component Is Detetermined

Efficiency of Pump:

where:

17 P = Effic iency of pump

Wp = Work.ed done by pump m = Mass flow rate hs = Entalphy of condenser h6 = Entalphy of pump

..... (2)

93

llltematio11al Semi11ar 011 Green Teclrnology and Engineering (ISGTE) MALAHA YATI UNIVERSI TY

Boiler

••

r. - - - -= I

A • I &..;

-

-

:-1

I I

I :.J

Figure 6: Energy Balance of Boiler

Turbine

Figure 7: Energy Balance of Steam Turbine

Condensot

<•:z+•3 )IIIO

' r. - --- -:"I

I I I

Its mathematical equation is:

q A = ml ( h, - hs) + q g

Efficiency of Boiler:

mt(ht -hs) 7] 8 = _..;......;._ __ qA

where: qg = Heat rejected from boiler qA = Heat input to boiler h1 = Entalphy of boiler h8 = Entalphy of FWH Its energy balance equation is:

..... (3)

..... (4)

..... (5)

Uj =7Ja · TJr(~~ -~~ -~n:J~ -m4h4) .... (6)

Its energy balance equation is:

(m2 + m3 )h10 + m4h4 = m5h5 + mC/!!11 ... (7)

Where:

m2 , m3 , m4 , m5 = Mass flowrate

m =Mass flowrate of cooling water (4300 AI kg/S)

.. I I '• • mCp ~..,; __

:.J

Figure 8: Energy Balance ofCondensor FWHJ

Figure 9: Energy Balance of FWH 1

94

Ct> = Specific heat of cooling water

( 4.19 k.JikgK)

q c = Heat absorbed by cooling water (Heat

is discarded to environment)

Its energy balance equation is:

ml(h, - h6)+(m2 +m3)h,o =m2~ +m3~ ..... (8)

International Seminar On Green Technology and Engineering (ISGTE) MALAHA YATI UNIVERSITY

FWH2 Its energy balance equation is:

...._...., _ _.m2h9

Figure 10: Energy Balance of FWH 2

3. The Mathematical Equations Of Performance Test Graph On January, June And December

..... (9)

And Energy Balance Are Set Up.

4. The Flow Chart Of Simulation Program Is Shown Below.

FLOW CHART OF SIMULATION PROGRAM

C.••ral Fonfl of ExparrsioJt of Taylor

S•riu EquatioJt

Differ~tiate fi to ai:) • tt (i,:)l

ttli,jl • z~a(i,jl~ x(j,ll t b [ i,jJ

No

95

lntemational Semi11ar On Green Technology and Engineering (ISGTE) MALAHA YA Tl UNIJIERSITY

5. Run the simulation program. 9. Compare thermal efficiency and electricity production yielded before and after simulation for each period

6. Thermal efficiency of each period is determined.

7. Frum the results: 18 variables those are looked for can be determined as: 4. RESULTS AND DISCUSSION Wr,' qA,' q8,' qc: m"· mz : lnJ,'

m.J; 'lk; 7J P; h6; h7; ha: h9; Based on performance test data for three periods on January, June and December and energy balance in steam power plant Bukit Asam cycle, the mathematical function equations that can be obtained as follows:

h,o; T8; T7; Ts 8. Determine thermal efficiency by

use of equation, Wr -w,

7J1h = x100% qA

Table I: Mathematical.function of equations

January 2003

T8 = -0,14 Wr2 + 18,3 Wr -406

71 p = 0,008 m12

- 4,0499 m1

+ 582,52

mt =- 0,0197 qA2 + 22,604 qA- 620l,J

T, =- 0,1136 Wr2 + 13,932 Wr-8,29

718 = 0,005 Wr2- 0,637 Wr

+ 111 ,8

June 2003

T8 =- 0,6 W/ + 71,8 Wr-1959

l]p= 0,0059 m12

- 2,9533 m1 +

442,63

m1 =- 0,0203 qA2 + 23,40) qA -6477,2

T7 = 0,0334 Wr2- 3,775 Wr +

298,26

'7 8 =- 0,0078 Wr2 + 0,98:}. Wr + 60,48

December 2003

T8 = 1,3018 Wr2- 145,69 Wr

+ 4246,8

l]p=- 0,0389 m12 + 19,309

m1 -2323,7

mt = 0,046 qA2- 50,97 qA +

14349

T, = 0,0202 Wl- 22,718 Wr -t: 818,91

178 =- 0,0205 Wr2 + 2,3268

Wr + 25,625

Wr = 0,0037 q/ + 4,3563 qA Wr =- 0,0037 q/ + 4,3519 qA -202,6 -1213, 1

Wr = 1,8867 qA2- 210,57 qA + 6413,5

Ts =- 0,722 Wr2 + 90,97 Wr-2466,3

T s - T 7 = - 2,2651 m2 2 +

832,35 mz- ...... -76356

Ts = 0,132 Wr2- 14,247 Wr + T8 = -2,5984 Wi + 307,6

770,9 Wr- 8670,1

Ts-T7=-8,8181 m/+3251,5 mz- ... ...- 299532

Ts-T7 =- 0,0072 m22 + 2,642

mz + 51,976

Table 2: Mathematical Function Equations of Energy Balance of Steam Power Plant Bukit Asam

I.

2.

96

Mathematical Equation of Balance of Energy (January, June and December) 2003

International Seminar On Green Technolov and Engineering (ISGTE) MALAHA YATI UNIVERSITY

3.

4.

5.

6.

7.

8.

9.

m1(h1 -hg) 17s = --'-----;...;...

qA m1 =m2 +m3 +m4

Wr =7Ja ·7Jr(m.Jr, -~~ -ml~ -m4h4)

(m2 + m3 )Jl.0 + m4h4 = m5h5 + mC,Ilt

~(h, -'%)+(~ +~)~o = ~~ +ml~

m.(hs -h? )=m2(h2 -~)

hg- h, = m.c p!lt

- Wr 10. qA - q8 + qc + --1'/arJr

After program runs, the operational variables for January, June and December 2003 are obtained (see Table 3) as fo llows:

Table 3: Results of Simulation Program, Operational Variables of Steam Power Plant

Year 2003 Varible Code Variable ·-

January June December x, Wr (MW) 58,594 61,018 60,594

x2 qA (MW) 327,589 4045,864 230,8.45

x3 q11

(MW) 22,668 146,653 128,635

x4 1'J B (%) 0,828 0,892 0,885

Xs "'" (%)

0,796 0,863 0,685

x6 Tg(°C) 174,900 175,687 198,675

X? T7 (°C) 212,223 188,204 197,562

Xs T8 c <>c) 341,021 239,605 223,502

x9 h6 (MJ/kg) 2,877 2,780 2,827

XIO h1 (MJ/kg) 4,667 4,366 2,545

x •• h8 {MJ/kg) 0,805 0,909 1,794

xl2 h9 (MJ/kg) 1,109 0,990 0,935

xl3 h10 MJ!kg) 2,202 1,705 1,679

Xt4 m1 (kgls) 86,832 85,476 83,580

Xts m2 (kgls) 169,607 180,550 181 ,099

Xt6 m3 (kg!s) 140,507 123,364 147,434

XI? m4 (kgls) 194,174 197,027 189,658

Xts qc (MW) 123,126 160,818 106,848

Based o.n the simulation results, comparison among each variable in each period is as indicated on Table 4 below:

97

lttlem atiottal Semittar Ott Greett Tecltnology and Engineering (JSGTE) MALAHAYATI UNIVERSITY

Table 4: Comparison of Operational Variable before and after Simulation

Year2003 Variable

January June December Code

New Old New Old New Old

Wr(MW) 58,594 57,1 61,018 60 60,594 57,33

qA (MW) 175,893 296,33 166,359 386,59 230,845 240,551

qg (MW) 22,668 21,347 146,653 146,723 128,635 128,635

TJs (%) 0,828 0,915 0,892 0,907 0,885 0,912

TJ I' (%) 0,796 0.704 0,863 0,713 0,684 0,704

Tg(°C) 174,900 185,66 175,687 179 198,675 187,4

T, (°C) 212,222 380,66 188,204 393,9 197,562 373,76

Ta (oC) 341,021 362,33 239,605 362,82 223,502 356,42

h6 (MJ!kg) 2,877 2,384 2,780 2,3129 2,827 2,321

h1 (MJ/kg) 4,667 36,04 4,366 36,06 2,545 37,66

h8 (MJ!kg) 0,805 0,90761 0,909 0,101 1,794 1,683

h9 (MJ!kg) 1,109 1,201 0,989 0,888 0,935 0,726

h10 MJ!kg) 2,202 2,320 1,705 1,605 1,679 1,255

m1 (kgls) 86,832 85, I 63 85,476 84,132 83,580 80,513

m 2 (kgls) 169,607 185,4 180,550 184,43 181,099 183,84

m3 (kgls) 140,507 141,563 123,364 133,277 147,434 139,257

m4 (kgls) 194,174 23 1,43 197,027 231,81 189,658 248,48

qc (MW) 123,126 143,502 160,818 158,827 106,848 106,688

From the results above, W 1'::: ml (h6 - hs) accumulatively one variable component

will regard the other ones that eventually T/p will impact in thermal efficiency of

· where: power plant. Thermal efficiency can be m1 =X14

calculated by using equation h6 = x9

WT -Wp 17th = hs = 2,2 78 MJ/kg

qA By assuming, 7]p= Xs

WT =XI The thermal efficiency before and after simulation is obtained as shown in Table

qA =X2 5.

98

International Seminar On Green Technology and Engineering (ISGTE) MALAHAYATI UNIVERSITY

Table 5: Comparison of thermal efficiency before and after simulation

Year 2003 Variable January June December Code

New Old New Old New Old x, 58,594 57,1 61 ,0180 60 60,594 57,33 x2 327,589 · 269,33 404,586 386,59 230,845 240,551 Xs 0,796 0,7034 0,863 0,713 0,684 0,704 Xg 2,877 2,384 2,780 2 313 2,827 2,321 x,4 86,832 85,163 78,475 84, 132 83,580 80 513

17th(%) 17,666 16,512 15,070 14,450 25,899 21,776

From the results above, it is 5. Sudarna, 2002, Optimasi Efisiensi acquired that the most profitable thermal

Boiller PLTU Suralaya, edisi efficiency increase is in December 2003 Januari. for 4% with electricity production http/www.eng.ui.ac.idlmesin increase to 3,26 MW. research/s2/ammar/resum % 20

5. CONCLUSION jurnal htm.

6. 1999, Sis tim This research has been conducted by Pembangkit Uap dengan

simulation of thermal efficiency of menggunakan Pembakaran steam power plant Bukit Asam. The Batubara Lignit, Puslitbang PT. method used in solving mathematical Bina Utama Asli, Jakarta. function equations of test performance 7. Wahyudin, 1999, Metoda Ana/isis data up to three periods fn one year and Numerik, Tarsito, Bandung. energy balance equations. After simulation has been performed, it is 8. Soemartoyo, N., 1997, Kalkulus acquired that thermal efficiency Lanjut, Universitas Indonesia. increases 4% and electricity production 9. John Mac Douglas, 1995, Potensi increases by 3,26 MW. Energi di Sumatera Selatan,

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10. Harjo. B, 1992, Simulasi Efisiensi

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Thermodinamika Teknik, Erlangga.

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llllernailollal S emitrar o, Green TechnologY. and Engineering (ISGTE) MALAHA YATI UNIVERSITY

14. Robert L. Ketter Sherwood P. Prawel, Jr, 1986, Modern Methods of Engineering Computatlon, Me. Graw Hill Book Company, New York.

100

15. Stoecker W. F, 1980. Design of Thermal System, Me Graw - Hill Kogakusha LTD.

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