SLOW PYROLYSIS OF SELECTED AGRICULTURAL WASTES: ANALYSIS OF THERMAL DEGRADATION BEHAVIOR

The use of fossil fuels produces carbon dioxide (CO2).  Carbon dioxide is one of the greenhouse gasses that contributes to global climate change. Due to this issue, there is increasing the requirement for the use of renewable materials and development of the additional sustainable process. Agricultural waste that has the property of fast growth, is an alternative renewable energy. In this work the slow pyrolysis of selected agricultural wastes mixture (cassava peel-rice straw, rice straw-rice husk, and cassava peel-rice husk) were studied to determine thermal degradation behavior of the biomass. The process was conducted in a fixed bed reactor at temperatures 325 °C, at 10 °C/min heating rate and at 10 min holding time. Results revealed that the moisture content of agricultural wastes were 4.40 % (cassava peel-rice husk), 5.48 % (rice straw-rice husk) and 8.12 %  (cassava peel-rice straw). The devolatilization process of the biomass was taken place in the temperature range from 189 oC to 325 oC. The volatile matter of each sample was 61.5%  for cassava peel-rice husk, 58.5 %  for rice straw-rice husk and 52.5 % for cassava peel-rice straw

Effect of Time and Frequency of Magnetic Field Application on MRF Pressure Performance

This research was conducted to determine the effect of the time and frequency of magnetic field application on MRF pressure performance. It was carried out by placing magnetorheological fluid (MRF) in a U-shaped, glass tube and then repeatedly applying a magnetic field to it for a certain time period with a particular frequency set by the generator frequency. The length of the application period of the magnetic field, the frequency of the application of the magnetic field, and the magnitude of changes in fluid pressure that occurred and changes in pressure in the MRF were recorded with a data logger for a specific time, which was 60 s. From the field tests that were carried out, it was found that during the application of a continuous magnetic field, there was pressure on the MRF until it reached the maximum pressure; then, there was a gradual decrease in pressure when the magnetic field was turned off, but the pressure was intense. It was shown that the pressure decreased rapidly as the magnetism disappeared, even causing the pressure to drop below the initial pressure, which, in turn, gradually rose again toward the equilibrium pressure. Meanwhile, during the repeated application of a magnetic field, it appeared that the MRF effectively produced pressure in response to the presence of a magnetic field up to a frequency of 5 Hz. The higher the applied magnetic field frequency, the smaller the pressure change that occurred. Starting at a frequency of 10 Hz, the application of a magnetic field produced more minor pressure changes, and the resulting pressure continued to decrease as the liquid level decreased toward the initial equilibrium position

Sistem Interkoneksi Data Antar Unit Guna Mendukung Keberhasilan Akreditasi Program Studi Pada Fakultas Teknik UNS

The research was carried out in  order   to   build   a   web­based   computer  application systems to support the smooth  process of accreditation of study programs by  BAN PT at the Faculty of Engineering, Sebelas  Maret University of Surakarta. It is planned to build a system that support the  accreditation   process   of   study   programs,  particularly   in   preparation   of   Borang  Akreditasi.   The   system   was   built   for   the  purpose of a database system to accommodate  the extraction data from administrative units  in   the   Faculty   of   Engineering,   University  Sebelas   Maret   Surakarta.   Development   of  systems and applications is done using open­ source software Linux­Ubuntu Server operating  system, the MySQL database server, and PHP  as programming language. The end result of this engineering­research is  developed   a   system   that   can   support   the  implementation of the accreditation in the  Faculty   of   Engineering   Universitas   Sebelas  Maret Surakarta

Sistem Interkoneksi Data Antar Unit Guna Mendukung Keberhasilan Akreditasi Program Studi Pada Fakultas Teknik UNS

The research was carried out in order to build a web-based computer application systems to support the smooth process of accreditation of study programs by BAN PT at the Faculty of Engineering, University Eleven March Surakarta. It is planned to build a system that support the accreditation process of study programs, particularly in preparation of Borang Akreditasi. The system was built for the purpose of a database system to accommodate the extraction data from administrative units in the Faculty of Engineering, University Sebelas Maret Surakarta. Development of systems and applications is done using open-source software Linux-Ubuntu Server operating system, the MySQL database server, and PHP as programming language. The end result of this engineering-research is developed a system that can support the implementation of the accreditation in the Faculty of Engineering Universitas Sebelas Maret Surakarta

Magnetically-Induced Pressure Generation in Magnetorheological Fluids under the Influence of Magnetic Fields

This study aims to observe the magnitude of the Magnetorheological Fluids (MRFs) pressure due to the application of a magnetic field. This was accomplished by placing the MRFs in a U-shaped tube, then applying a magnetic field generated by a magnetic coil. A finite element simulation for the magnetic field was carried out to estimate the magnetic field strength generated by the coil variable to the current input given in the simulated apparatus. Changes in MRFs pressure were recorded using a data logger to better observe the fluid pressure phenomena occurring in the MRFs with respect to current input variations. The results showed that the magnetic field influences the MRFs fluid pressure proportionally. The slope is not constant as the magnetic field effect to the fluid pressure gets stronger when the current input is higher. However, there are also an adverse effect of heat generated in the coil in higher current, which results in coil performance degradation and reduces the magnetic field strength

ANALISA THERMOGRAVIMETRY PADA PIROLISIS LIMBAH PERTANIAN

Penelitian ini bertujuan untuk menemukan karakterisasi degradasi termal dari limbah pertanian untuk dijadikan suatu bahan bakar padat alternatif. Penelitian diawali dengan tahap pengumpulan bahan yang dilanjutkan penyeragaman ukuran sampel uji hingga berukuran 20 mesh. Setelah itu masing-masing sampel dikeringkan hingga kadar air maksimal 12 %. Sebelum Sampel seberat 20 gram diuji pirolisis dengan menempatkan sampel dalam reaktor yang telah dialiri nitrogen dengan laju 100 ml/menit. Sampel diuji dengan kondisi heating rate 15 oC/menit, temperatur akhir 600 oC dan holding time 10 menit. Data yang didapat berupa penurunan massa dan perubahan temperatur dicatat dalam laptop dengan menggunakan software RS-Key, Ms Excel dan Adam.NET Utility. Dari penelitian yang telah dilakukan, maka dapat disimpulkan campuran serbuk gergaji dan jerami memiliki temperatur pirolisis paling rendah, sementara campuran sekam padi dan kulit singkong memiliki massa arang paling banyak