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Efek Zeolit untuk Produksi Tar dan Char pada Pirolisis Rotary Kiln Wijayanti, Widya
Jurnal Rekayasa Mesin Vol 12, No 1 (2021)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2021.012.01.6

Abstract

This study aims to investigate the effect of zeolite as a catalyst to enlarge biomass decomposition in the pyrolysis process. It absorbs a high water content in the biomass, besides it makes the easier breaking of biomass molecules to maximize the biomass decomposition into the expected pyrolysis products; tar and char. In addition, to decompose the biomass molecules, the zeolite also stimulates the rate of heat transfer due to its ability to hold and release the heat. If the previous research pyrolysis was conducted in a fixed bed reactor, in this study, it will be carried out rotary kiln as a pyrolysis furnace. If the fixed bed reactor the heat transfer was dominated by conduction, the heat transfer in the rotary kiln is more controlled by the convection and radiation transfer due to stirring and turning of biomass by the kiln. In the study, the biomass used was mahogany with an initial weight of 150 grams. The rotary kiln rotated at 10 rpm and the heating rate during the pyrolysis process was around 0.1483°C/s. The pyrolysis temperatures used were varied as 250°C, 350°C, 450°C. Meanwhile, the percentage of zeolites used from 0% to 60% with a mesh size of 80. The results showed that zeolites were able to increase tar production and maximize the reduction of char as an effect of the Bronsted-Lowry and Lewis reaction in the process of catalytic cracking. The maximum production of tar and char production was also supported by the process of convection and radiation from the rotary kiln wall increasing the rate of heat transfer to decompose the biomass. 
Efek Bentonit pada Karakteristik Pembakaran Droplet Biodiesel Kelapa Sawit Wijayanto, Vera Dwi; Hamidi, Nurkholis; Wijayanti, Widya
Jurnal Rekayasa Mesin Vol 11, No 3 (2020)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2020.011.03.4

Abstract

The blends of fuel to base liquid fuels for the enhancement of combustion properties has long generated interest since it is linked to improvement in combustion properties in biodiesel fuels. This work investigates the effect of bentonite nanoparticles on the combustion characteristics of palm oil biodiesel. These nanoparticles are added in various compositions on biodiesel which are 0% (B0), 10% (B10), 20% (B20) and 30% (B30). The insulin pen was used to make Sub-millimeter-sized spherical droplets, and the combustion process of droplets was recorded using a camera in atmosphere condition. The fuel was dripped on the tip of the thermocouple junction and ignited using a torch of the butane-air mixture on a cylindrical burner. Properties such as ignition delay, burning rate, and flame temperature of droplets were measured with post-processing of the resulting images. The results showed a decrease in ignition delay and an increase of flame temperature with the increase of bentonite percentage due to bentonite acts as a catalyst capable of accelerating the reaction rate. However, the burning rate decrease with the increasing of bentonite percentage due to the oxygen content of the mixture is getting lower.
ADVANCED TURBINE WORKING: IMPACT OF WINGLET ON VERTICAL WIND TURBINE DARRIEUS TIPE H Amir, Ahmad Ihwan; Soenoko, Rudy; Wijayanti, Widya; Setiadhi, David
International Journal of Mechanical Engineering Technologies and Applications Vol. 5 No. 1 (2024)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2024.005.01.8

Abstract

In this study, the effect of winglets on improving the performance of type h darrieus wind turbines was investigated. The aim is to determine the most suitable winglet design and find out the magnitude of the increase in wind turbine performance. The method used is experimentation to find the RPM and torque used for calculate the TSR value and turbine power. From all the trial and error experiments, the type of blended winglet that best suited the characteristics of the VAWT. The experimental results show that the addition of blended winglet increases RPM of 13.6% in the 3-blade turbine and turbine it increases of 9% in the 4-blade turbine. The increase in average torque is 13.2% in a 3-blade turbine and 9.4% in a 4-blade turbine. The average increase in power coefficient is 11% in a 3-blade turbine and 9% in a 4-blade blade. In conclusion, the addition of blended winglets produces better torque and power compared to turbine models without winglets.
Study of Thermal Behavior in Mixed Scrap Tires (ST) And Polypropylene (PP) Plastic Using Thermogravimetry Analysis (TGA) and Differential Scanning Calorimetry (DSC) Sofana, Ilyas; Wijayanti, Widya; Hamidi, Nurkholis
International Journal of Mechanical Engineering Technologies and Applications Vol. 3 No. 2 (2022)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2022.003.02.7

Abstract

The world's rapid population growth, technological progress, and industrialization lead to an increase in fossil energy demand such as oil, coal, and natural gas. It is feared that this could lead to a scarcity of fossil energy in the future, therefore the use of alternative energy must be considered. One interesting concept to develop is waste to energy by utilizing plastic waste and also tires on vehicles. This is very possible because the two wastes contain elements of hydrocarbons which are also contained in fossil fuels so they can be processed to become alternative energy which can simultaneously reduce the population of the waste due to the increase in the world's population. This study aims to investigate the thermal behavior of scrap tires (ST) and polypropylene (PP) plastic using thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). TGA thermogram showed that the feedstock samples were degraded in the temperature range of 331,97 oC to 448,08 oC. The interpretation of the DSC thermogram that showing information about the glass transition point and the melting point of the feedstock polymer will also be presented in this study.
Pengembangan Media PowerPoint IPA Untuk Siswa Kelas IV SD Negeri Samirono Wijayanti, Widya; Christian Relmasira, Stefanus
Jurnal Penelitian dan Pengembangan Pendidikan Vol. 3 No. 2 (2019): Juli
Publisher : LPPM Undiksha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jppp.v3i2.17381

Abstract

Penelitian ini merupakan penelitian Research and Development yang menghasilkan media  berupa media pembelajaran berbasis teknologi terutama media PowerPoint IPA untuk siswa kelas IV.  Penelitian ini bertujuan untuk kebutuhan sekolah, meningkatkan ketertarikan dan menghasilkan media PowerPoint untuk peserta didik yang layak. Pengembangan media PowerPoint dilakukan dengan 3 langkah pokok yang harus dilakukan yaitu yang Pertama, studi pendahuluan untuk mengetahui kebutuhan Sekolah Dasar dan pentingnya media. Kedua, penyusunan draft produk memulai tahap pembuatan desain PowerPoint, validasi materi, validasi media. Ketiga,  uji coba produk untuk siswa kelas IV. Hasil penelitian ini berupa media pembelajaran berbasis Teknologi terutama PowerPoint yang berisi materi pendidikan IPA Subtema 2 yang telah divalidasi oleh ahli media, ahli materi, dan dinyatakan layak. Media PowerPoint telah diuji cobakan kepada siswa Sekolah Dasar dan siswa mampu memahami materi IPA tentang Selalu Menghemat Energi. Pada tujuan Pengembangan Media PowerPoint IPA menggunakan model AADIE untuk mengetahuo seberapa tinggi validasi produk model oleh ahli. Valdasi materi pembelajaran oleh ahli materi diperoleh sebesar 75,5% dengan kategori tinggi dan validasi media pembelajaran oleh ahli media diperoleh sebesar 46,25% dengan kategori tinggi. Selain mengetahui seberapa tinggi validasi ahli juga untuk melihat apakah media PowerPoint dapat menarik siswa dalam pembelajaran menggunakan teknologi.
Enhanced Hydrogen Production from Biomass Pyrolysis using Surfactant-Modified Na-Bentonite Catalyst Irawan, Dwi; Wijayanti, Widya; Wahyudi, Slamet; Kusumo, Herma Nugroho Rono Adi; Yani, Ahmad; Wardana, I.N.G.
ASEAN Journal of Science and Engineering Vol 5, No 3 (2025): AJSE: December 2025
Publisher : Universitas Pendidikan Indonesia (UPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/ajse.v5i3.88898

Abstract

This study investigates the improvement of hydrogen gas production in biomass pyrolysis through the use of Na-bentonite catalysts modified with methyl ester sulfonate (MES), a biodegradable anionic surfactant. Corn cob powder was used as the biomass feedstock in a fixed-bed pyrolysis reactor at 550°C. The MES modification introduced alkyl, ester, and sulfonate functional groups, increasing the catalyst porosity, surface area, and acidity. Structural and chemical changes were confirmed by FTIR, XRD, UV-Vis, SEM, and EDX analyses. The MES-modified Na-bentonite catalyst significantly enhanced hydrogen production, reaching 876 ppm (a 25.11% increase compared to pyrolysis without a catalyst) and also lowered the reaction temperature and shortened the reaction time. Methane production decreased as MES improved catalyst selectivity toward dehydrogenation pathways. The results indicate that MES-modified Na-bentonite is a low-cost, efficient, and environmentally friendly catalyst suitable for improving hydrogen yields in biomass pyrolysis, offering a promising alternative to conventional metal-based catalysts.
Study of Thermal Behavior in Mixed Scrap Tires (ST) And Polypropylene (PP) Plastic Using Thermogravimetry Analysis (TGA) and Differential Scanning Calorimetry (DSC) Sofana, Ilyas; Wijayanti, Widya; Hamidi, Nurkholis
International Journal of Mechanical Engineering Technologies and Applications Vol. 3 No. 2 (2022)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2022.003.02.7

Abstract

The world's rapid population growth, technological progress, and industrialization lead to an increase in fossil energy demand such as oil, coal, and natural gas. It is feared that this could lead to a scarcity of fossil energy in the future, therefore the use of alternative energy must be considered. One interesting concept to develop is waste to energy by utilizing plastic waste and also tires on vehicles. This is very possible because the two wastes contain elements of hydrocarbons which are also contained in fossil fuels so they can be processed to become alternative energy which can simultaneously reduce the population of the waste due to the increase in the world's population. This study aims to investigate the thermal behavior of scrap tires (ST) and polypropylene (PP) plastic using thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). TGA thermogram showed that the feedstock samples were degraded in the temperature range of 331,97 oC to 448,08 oC. The interpretation of the DSC thermogram that showing information about the glass transition point and the melting point of the feedstock polymer will also be presented in this study.
ADVANCED TURBINE WORKING: IMPACT OF WINGLET ON VERTICAL WIND TURBINE DARRIEUS TIPE H Amir, Ahmad Ihwan; Soenoko, Rudy; Wijayanti, Widya; Setiadhi, David
International Journal of Mechanical Engineering Technologies and Applications Vol. 5 No. 1 (2024)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2024.005.01.8

Abstract

In this study, the effect of winglets on improving the performance of type h darrieus wind turbines was investigated. The aim is to determine the most suitable winglet design and find out the magnitude of the increase in wind turbine performance. The method used is experimentation to find the RPM and torque used for calculate the TSR value and turbine power. From all the trial and error experiments, the type of blended winglet that best suited the characteristics of the VAWT. The experimental results show that the addition of blended winglet increases RPM of 13.6% in the 3-blade turbine and turbine it increases of 9% in the 4-blade turbine. The increase in average torque is 13.2% in a 3-blade turbine and 9.4% in a 4-blade turbine. The average increase in power coefficient is 11% in a 3-blade turbine and 9% in a 4-blade blade. In conclusion, the addition of blended winglets produces better torque and power compared to turbine models without winglets.
Pemanfaatan sifat Wettability Minyak Nabati untuk meningkatkan Cleanability pada kasus Fouling Rizza, Muhammad Akhlis; Wardana, I Nyoman Gede; Hamidi, Nurkholis; Wijayanti, Widya
Prosiding SNPBS (Seminar Nasional Pendidikan Biologi dan Saintek) 2017: Prosiding SNPBS (Seminar Nasional Pendidikan Biologi dan Saintek)
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (243.781 KB)

Abstract

Fouling menjadi permsalahan pada proses produksi di suatu industri, terutama industri yang memiliki prosesperpindahan panas. Fouling dapat mengurangi perpindahan panas yang terjadi. Oleh karena itu terjadinyafouling harus diatasi dengan cleaning yang cepat. Untuk mempercepat proses cleaning, terutama pada foulingdengan material droplet minyak nabati dapat dilakukan dengan memanfaatkan sifat wettability. Sifatwettability dapat diatur dengan mengatur temperatur pada droplet. Tujuan analisis ini adalah mengetahuifaktor-faktor yang berpengaruh pada wettability, sehingga dapat dipakai untuk memudahkan proses cleaning. Berdasarkan analisis, diperoleh kesimpulan bahwa wettability dipengaruhi oleh temperatur minyak nabatiserta kerataan permukaan substrate-nya.
Investigasi Terhadap Hasil Proses Pyrolisis Sampah Plastik Jenis Pet Dengan Katalis Alam Dari Klaten Jawa Tengah Indonesia Nuryosuwito, Nuryosuwito; S., Sudjito; Wijayanti, Widya; Hamidi, Nurcholis; Mufarrih, Am.
Prosiding SEMNAS INOTEK (Seminar Nasional Inovasi Teknologi) Vol. 2 No. 1 (2018): PROSIDING SEMNAS INOTEK Ke-II Tahun 2018
Publisher : Universitas Nusantara PGRI Kediri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29407/inotek.v2i1.466

Abstract

Produksi plastik global meningkat selama bertahun-tahun karena banyaknya aplikasi plastik di banyak sektor. Permintaan terus menerus dari plastik menyebabkan akumulasi limbah plastik di TPA menghabiskan banyak ruang yang berkontribusi terhadap masalah lingkungan. Meningkatnya permintaan plastik menyebabkan pelepasan minyak bumi sebagai bagian dari bahan bakar fosil yang tidak terbarukan karena plastik adalah bahan berbasis minyak bumi. oleh karena itu dalam penelitian ini akan dilakukan studi terhadap karakteristik pirolisis, material Sampah plastik PET dengan katalis alam Klaten, Jawa Tengah, Indonesia. Dari hasil proses pirolisis menunjukkan bahwa jenis bahan baku sangat mempengaruhi hasil produk dan kualitas produk cair dan padat Sampah plastik PET menghasilkan fraksi cairan tertinggi. Paduan katalis mengurangi fraksi cairan dan meningkatkan fraksi gas. Selanjutnya, sampah plastik kotamadya menghasilkan produk dengan nilai lebih tinggi dari pada produk biomassa sampah plastik bisa digunakan sebagai bahan bakar alternatif.