Institutional Repository | Satya Wacana Christian University: Rancang Bangun Alat Pembuat Biogas Dari Eceng Gondok

RANCANG BANGUN ALAT PEMBUAT BIOGAS DARI
ECENG GONDOK

Oleh
Agustinus Dhani Setiawan
NIM: 612008020

Skripsi
Untuk melengkapi salah satu syarat memperoleh
Gelar Sarjana Teknik
Program Studi Teknik Elektro
Fakultas Teknik Elektronika dan Komputer
Universitas Kristen Satya Wacana
Salatiga

Januari 2015

RANCANG BAI\GI,N ALAT PEMBUAT BIOGAS I}ARI ECENG GONDOK

Oleh
Agustinus Dhani Setiawan


NIM:

612008020

Skripsi ini telah diterima dan disahkan
Untuk melengkapi salah satu symat memperoleh
Gelar Sarjana Teknik
dalam
Konsentrasi Teknik Elekkonika
Prograrn Studi Teknik Elektro
Fakultas Teknik Elekhonika dan Komputer
Universitas Kristen Satya Wacana
Salatiga

Disahkan oleh

Pembimbing

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ABSTRACT

Eceng gondok are floating water plants that usually grow in a pond, swamp,
ricefield, lake, river, and slowly-flowing water. Eceng gondok has a high growth rate so it
is considered as a gulma that can damage the surrounding environments. Nowadays, eceng
gondok begins to be utilized as handicrafts, composts, even biogas. Biogas energy
conservation are still seldom because of lack of comprehension, working steps, and biogas
application which are still traditionally mannered. That include: eceng gondok must be
chopped manually to speed up fermentation process, big fermentation digester and must be
buried to keep the temperature and also lack of biogas process monitoring.
Due to those factors, we designed a biogas making tool that use chopping machine
to make the working process easier by using fermentation tank that is not buried and can be
moved as well as to provide biogas process monitoring. Working steps of this are tool:
eceng gondok that have been cleaned from manure and mud are put into chopping machine.
The result of chopped eceng gondok are then connected to fermentation tank. Then the
fermentation process last about 2 weeks. Monitoring will show the presence of methane gas
as the main biogas and show the increasing of temperature if the fermentation process
begins to produce methane gas.
The result of experiment shows that chopping tool works to chop eceng gondok
about 60 kgs in an hour with the chopped results ranging between 1 to 6 cms (adequate to
ease fermentation process). Fermentation process last for 16 days with tank if the
fermentation is always exposed to sun light in the day period. The gas that is produced in

the fermentation tank have a certain capacity about 289 liters and can be used to cook about
an hour.

KATA PENGANTAR

Puji dan syukur kepada Allah Bapa Yang Maha Kuasa atas berkat dan rahmat
karuniaNya yang senantiasa penulis terima dalam menyelesaikan perancangan dan
penulisan skripsi ini sebagai syarat untuk menyelesaikan studi di Fakultas Teknik
Elektronika dan Komputer Universitas Kristen Satya Wacana.
Pada kesempatan ini penulis juga mengucapkan terimakasih kepada berbagai pihak
baik yang secara langsung maupun tidak langsung telah membantu dalam menyelesaikan
skripsi ini :
1. Tuhan Yesus Kristus yang selalu senantiasa memberikan penulis rahmat, karunia,
dan kesehatan

sehingga penulis dapat menyelesaikan skripsi ini dengan baik.

“Segala perkara dapat kutanggung dalam Dia yang memberi kekuatan kepadaku”.
(Filipi 4:13)
2. Keluarga tercinta FA. Hartoyo, Rosalia Murni, Andreas Effry, Lucia Novitasari,

Emilia Purnamadewi, Joko Sulistyo, terima kasih untuk segala doa, dukungan dan
perhatian kalian kepada penulis untuk tetap semangat dalam menyelesaikan skripsi
ini.
3. Bapak Gunawan Dewantoro, M.Sc.M.Eng dan bapak Deddy Susilo,M.Eng selaku
pembimbing I dan pembimbing II, terima kasih atas segala bimbingan dan arahan
yang membantu menginspirasi penulis selama menyelesaikan skripsi ini.
4. Seluruh staff dosen, karyawan, dan laboran FTEK.
5. Teman teman angkatan 2008, LAB XT seperjuangan skripsi, Demas 08, Gading
08,Meyhart 08, kristo 08, Rudi 08 , catur 08, Eko 08, Dung 08, Jembling 08, Reno
08,Endro 08, Galang 07,Eko 07, Robot 07, Reno 07, DK, Ari, Trisno, Dito, Sembir.
6. Vicencia Adinda Resita Herawati dan keluarga yang selalu memberi semangat dan
doa dalam mengerjakan skripsi ini.
7. Teman teman OMK Pius X Karanganyar

8. Berbagai pihak yang tidak dapat dituliskan satu persatu, penulis mengucapkan
terima kasih atas bantuan dan keterlibatan dalam pengerjaan skripsi ini.
Penulis menyadari bahwa skripsi ini masih jauh dari kata sempurna, oleh karena itu penulis
mengharapkan kritik maupun saran dari pembaca sekalian sehingga skripsi ini dapat
berguna untuk pengembangan selanjutnya dan bagi kemajuan FTEK.


Salatiga, Januari 2015

Penulis

DAFTAR ISI

INTISARI ............................................................................................................................... i
ABSTRACT........................................................................................................................... ii
KATA PENGANTAR .......................................................................................................... iii
DAFTAR ISI.......................................................................................................................... v
DAFTAR GAMBAR ........................................................................................................... vii
DAFTAR TABEL.................................................................................................................. ix
DAFTAR GRAFIK ................................................................................................................ x
DAFTAR SINGKATAN ...................................................................................................... xi
BAB I

PENDAHULUAN ............................................................................................. 1
1.1 Tujuan ........................................................................................................... 1
1.2 Latar Belakang .............................................................................................. 1
1.3 Spesifikasi Sistem ......................................................................................... 2

1.4 Sistem Penulisan ........................................................................................... 3

BAB II

DASAR TEORI ................................................................................................. 4
2.1 Biogas ........................................................................................................... 4
2.2 Sensor Gas TGS2610 .................................................................................... 7
2.3 Sensor Suhu Termokopel .............................................................................. 8
2.4 Sensor Tekanan MPX 5500D ..................................................................... 12
2.5 Mikrokontroler AVR Atmega 8535 ............................................................ 13
2.6 LCD Karakter 20x4..................................................................................... 14

BAB III

PERANCANGAN SISTEM ........................................................................... 16
3.1 Gambaran Sistem ........................................................................................ 16

3.2 Perancangan dan Realiasasi Perangkat Keras ............................................. 16
3.2.1 Kontroler Utama ............................................................................. 17
3.2.1.1 Catu Daya ............................................................................. 17

3.2.1.2 Board Mikrokontroler........................................................... 18
3.2.1.3 ADC ..................................................................................... 18
3.2.1.4 LCD Karakter 20x4 .............................................................. 19
3.2.1.5 Perancangan Modul Sensor Gas ........................................... 20
3.2.1.6 Perancangan Modul Sensor Suhu ......................................... 21
3.2.1.7 Perancangan Modul Sensor Tekanan ................................... 23
3.2.2 Mekanik .......................................................................................... 23
3.2.2.1 Mesin Pencacah .................................................................... 24
3.2.2.2 Tabung Digester Fermentasi ................................................ 26
3.3 Perangkat Lunak ......................................................................................... 27
BAB IV

PENGUJIAN DAN ANALISIS ...................................................................... 30
4.1 Pengujian Sensor gas TGS 2610 ................................................................. 30
4.2 Pengujian sensor suhu termokopel.............................................................. 32
4.3 Pengujian sensor tekanan MPX 5500D ...................................................... 35
4.4 Pengujian Led Indikator Air ....................................................................... 36
4.5 Pengujian Mesin Cacah............................................................................... 36
4.6 Pengujian Hasil Biogas ............................................................................... 38


BAB V

KESIMPULAN DAN SARAN ....................................................................... 41
5.1 Kesimpulan ................................................................................................. 41
5.2 Saran .......................................................................................................... 41

LAMPIRAN PANDUAN PENGGUNAAN ..................................................................... 42
DAFTAR PUSTAKA .......................................................................................................... 46

DAFTAR GAMBAR

Gambar 2.1 Skema digester biogas tipe fixed dome plant ..................................................... 5
Gambar 2.2 Digester Dar Es Salaam, Tanzania dan model yang sama dari BIOTECH ....... 6
Gambar 2.3 Desain digester kementrian negara lingkungan hidup ....................................... 6
Gambar 2.4 Sensor gas TGS 2610 ......................................................................................... 7
Gambar 2.5 Skema sensor gas ............................................................................................... 7
Gambar 2.6 Diagram skematik termokopel ........................................................................... 8
Gambar 2.7 Pengukuran EMF ............................................................................................... 8
Gambar 2.8 Ilustrasi hukum termoelektrik ke 2 .................................................................... 9
Ganbar 2.9 Ilustrasi hukum termoelektrik ke 3 ..................................................................... 9

Gambar 2.10 Bak es sebagai reference junction.................................................................. 10
Gambar 2.11 Jenis junction termokopel .............................................................................. 11
Gambar 2.12 MPX 5500D CASE case 867-08 .................................................................... 13
Gambar 2.13 Konfigurasi pin mikrokontroler Atmega 8535............................................... 13
Gambar 2.14 LCD 20x4 karakter ........................................................................................ 15
Gambar 3.1 Blok diagram sistem kontroler utama .............................................................. 16
Gambar 3.2 Realisasi boks kontroler utama ........................................................................ 17
Gambar 3.3 Perancangan catu daya ..................................................................................... 18
Gambar 3.4 LCD karakter 20x4 .......................................................................................... 19
Gambar 3.5 Skema sensor gas ............................................................................................. 20
Gambar 3.6 Termokopel tipe K ........................................................................................... 20
Gambar 3.7 Blok diagram AD595 ....................................................................................... 21
Gambar 3.8 Blok diagram sensor tekanan ........................................................................... 23
Gambar 3.9.A Realisasi alat yang dirancang ....................................................................... 24
Gambar 3.9.B Penampang letak sensor yang dirancang ...................................................... 24
Gambar 3.10 Mesin pencacah .............................................................................................. 25
Gambar 3.11 Pisau pencacah ............................................................................................... 25
Gambar 3.12 Motor mesin listrik AC .................................................................................. 26

Gambar 3.13 Digerster dengan passive solar heat .............................................................. 27

Gambar 3.14 Sub rutin program mikrokontroler ................................................................. 28
Gambar 4.1 Tempat pengujian sensor gas ........................................................................... 30
Gambar 4.2 Pengukuran dengan gas detector seri 7291 ..................................................... 31
Gambar 4.3 Pengujian dengan FLUKE 287 true RMS multimeter ...................................... 34
Gambar 4.4 Pengujian sensor tekanan ................................................................................. 36
Gambar 4.5 Hasil cacahan ................................................................................................... 37
Gambar 4.6 Pengujian biogas .............................................................................................. 38

DAFTAR TABEL

Tabel 2.1 Konfigurasi pin LCD 20x4 .................................................................................. 14
Tabel 3.1 Konfigurasi penggunaan pin/port mikrokontroler Atmega 8535 ........................ 18
Tabel 3.2 Pengukuran arus keluaran TGS 2610 .................................................................. 20
Tabel 3.3 Nilai perubahan tegangan termokopel dan tegangan AD595 terhadap suhu ....... 22
Tabel 4.1 Nilai ADC terhadap konsentrasi biogas .............................................................. 31
Tabel 4.2 Hasil pengujian sensor suhu ................................................................................ 33
Tabel 4.3 Pengujian sensor tekanan ..................................................................................... 35

DAFTAR GRAFIK

Grafik 2.1 Tegangan keluaran dengan tekanan ................................................................... 12
Grafik 4.1 Nilai perbandingan ADC dan ppm gas ............................................................... 32
Grafik 4.2 Perbandingan suhu dengan tegangan terbaca ..................................................... 34
Grafik 4.3 Pengujian tekanan dan tegngan keluaran dari sensor MPX5500D .................... 35
Grafik 4.4 Tekanan dan tegangan keluaran dari sensor MPX5500D pada datasheet .......... 36

DAFTAR SINGKATAN
BLH

Badan Lingkungan Hidup

LCD

Liquid Crystal Display

LED

Light Emitting Diode

PLN

Perusahaan Listrik Negara

AC

Allternative Current

AVR

Alf and Vegard’s Risc Processor

ADC

Analog to Digital Converter

EMF

Electromotive force

CJC

Cold Junction

RISC

Reduced Instruction Set Computing

EEPROM

Electrically Erasable Programmable Read-Only Memory

SRAM

Static Random Access Memory

USART

Universal Synchronous/Asynchronous Receiver/Transmitter

I2C

Inter-Integrated Circuit

PPM

Part Per Millions

kPa

kilo Pascal

HP

Horse Power

RPM

Rotation Per Minute

RMS

Root Mean Square

IC

Integrated Circuit