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Contact Name
Alfian Qomaruddin
Contact Email
alfian@trunojoyo.ac.id
Phone
-
Journal Mail Official
rekayasa@trunojoyo.ac.id
Editorial Address
Universitas Trunojoyo Madura Jl. Raya Telang - Kamal, Bangkalan Kode Pos 69162
Location
Kab. bangkalan,
Jawa timur
INDONESIA
REKAYASA
ISSN : 02169495     EISSN : 25025325     DOI : https://doi.org/10.21107/rekayasa
This journal encompasses original research articles, review articles, and short communications, including: Science and Technology, In the the next year publication, Rekayasa will publish in two times issues: April and Oktober.
Arjuna Subject : -
Articles 504 Documents
Pemanfaatan Air Gambut Untuk Meningkatkan Kualitas Produksi Biocoal dari Limbah Tandan Kosong Kelapa Sawit Dengan Variasi Waktu dan Temperatur Proses Torefaksi Martin, Awaludin
Rekayasa Vol 14, No 3: Desember 2021
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v14i3.12226

Abstract

Efforts to increase the use of new and renewable energy continue to be carried out where the one of the programs is to seek the use of mixed fuels (co firing) in fossil fuel power plants such as steam power plant. The main fuel in steam power plant mostly uses coal and the mixed fuel can be used as biomass fuel. Palm oil empty fruit bunches are one of the potentially large biomass that can be used as mixed fuel because of its abundant availability, especially in Riau Province. However, palm oil empty fruit bunches have a low heating value of combustion, so the treatment needs to be carried out in order to palm oil empty fruit bunches as biomass fuel have a high heating value. This study aims to increase the heating value of palm oil empty fruit bunches by torrefaction process so that palm oil empty fruit bunches have a high heating value and equivalent to the heating value of coal. The torrefaction process is carried out with variations in time and temperature of torrefaction, namely 30 - 60 minutes and 200oC - 300oC. The research carried out results in the largest heating value of 7470.59 kcal/kg at a time process of 60 minutes and a torrefaction temperature of 300oC.
Studi Eksperimen Biomassa Padat Sebagai Bahan Bakar Alternatif Menggunakan Campuran Limbah Pertanian Annisa, Rullie; Wahyuni, Sri; Irawan, Ibnu; Anam, Sayidil
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.12905

Abstract

Biomass is one of the agricultural wastes that can be used as a substitute for alternative fuels. The biomass needs to be converted into briquettes first, so that it becomes an environmentally friendly fuel. Corn cobs and rice straw are the most common types of agricultural products found in East Java, therefore the potential for alternative fuels that will be obtained will also be higher. This research aims to determine the characteristics of solid fuels (briquettes) including: calorific value of briquettes, water content of briquettes, ash content of briquettes and drop test on briquettes using a mixture of corn cobs and rice straw. The variation of the mixture between corn cobs and rice straw is 1 kg, where 1 kg of corn cobs and straw using a mixture ratio of 90%:10%, 80%:20%, 70%:30% and 60%:40% using starch adhesive of 0.001 kg. In addition, it uses two pressure variations, namely: A = 2500 kPa and B = 5000 kPa which are used in briquettes. The results of the research on the characteristics of briquettes such as: The highest calorific value using a mixture of 90% corn cobs and 10% rice straw was obtain at 5546.74 cal/gram. The most optimal moisture content using a suppression load of 5000 kPa using a mixture of 90% corn cobs and 10% rice straw obtained a value of 11.30%. The optimal ash content produced also uses a suppression load of 5000 kPa by using a mixture of 90% corn cobs and 10% rice straw to obtain a value of 20.58%. While the drop test on briquettes using a pressing load of 5000 kPa by using a mixture of 60% corn cobs and 40% rice straw obtained a value of 11.10%, a large reduction in particle size when applied from a height.
Unjuk Kerja Performa Turbin Arus Laut Sumbu Vertikal Pada Berbagai Bentuk Sudu Unik Rizki Mendung Ariefianto; Rini Nur Hasanah; Wijono Wijono
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13572

Abstract

Efficiency and self-starting capability performances are the main problems in vertical axis turbines. By purposing improves its performance, vertical axis turbines have been developed with various models. One of the developments of this model is to design the turbine blades into unique shapes. This research aims to determine the performance of some unique blade vertical axis turbines conditioned on the same parameters, especially if applied in a marine environment. Turbines with helical blade (HB), eggbeater-shaped blade (ESB), diamond-shaped blade (DSB), Y-shaped blade (YSB), and arrow-shaped blade (ASB) were investigated based on efficiency and self-starting capability using QBlade software. Good performance symmetrical foils such as NACA 634021 are also applied to each turbine. The simulation results show that from the aspect of efficiency performance, turbine ASB more than HB more than ESB more than DSB more than YSB. Meanwhile, in the aspect of self-starting capability performance, the sequence is similar to efficiency performance, based on the two approaches applied. The highest efficiency achieved by the ASB turbine is 0.391 at the lowest tip speed ratio of λ = 4. The ASB turbine also achieves the best self-starting performance, which has a minimum static torque coefficient of 0.00155 and can produce the required power at the lowest marine current speed of 0.806 m/s. This performance brings the ASB turbine to produce a rated power of 52.52 kW, or more than twice the power production of the lowest efficiency turbine and has an average power gain of 3.75 kW per 0.2 m/s.
Pendugaan Umur Simpan Garam Mandi (Bath Salt) Aroma Serreh Menggunakan Metode Accelerated Shelf Life Testing (ASLT) Putri, Meilinda Cendana; Maflahah, Iffan; Supriyanto, Supriyanto; Asfan, Dian Farida
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13855

Abstract

Salt contains compounds of magnesium chloride, magnesium sulfate, magnesium bromide, and other trace compounds. In general, salt is divided into consumption salt and industrial salt. Bath salt is a salt product that dissolves in water and reduces wrinkles on the hands. The constituent components of bath salts are Epsom salt, sodium bicarbonate, SLES, cornstarch, olive oil, citronella oil, and alcohol, the packaging used is glass packaging. Shelf life is done by accelerating the degradation reaction using high temperature storage and simulating the data obtained. The purpose of this study was to determine the quality characteristics of bath salts before and after storage and to determine the shelf life of bath salts with the aroma of lemongrass. This research was conducted at the Quality Analysis Lab of the Agricultural Industrial Technology Study Program, Faculty of Agriculture, Trunojoyo University, Madura from September to October 2021. Shelf life was estimated using the Arrhenius method. Based on research at a temperature of 28, the shelf life of bath salts is 180.86 or 6 months 1 day, while at a temperature of 35 is 85.85 or 2 months 26 days. It is proven by the value of the shelf life which is getting shorter with the higher the storage temperature. An increase in temperature causes a greater rate of reaction
Aktivitas Antioksidan dan Antibakteri Ekstrak Daun Kersen (Muntingia Calabura L) dengan Metode Microwave Assisted Extraction Mutammimah, Siti; Supriyanto, Supriyanto; Mu’tamar, Mohammad Fuad Fauzul
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13229

Abstract

Kersen (Mutingia calabura) is a wild plant that is not cultivated and not many people know its benefits. So far kersen plants are only used as a shade even though the plant has the potential as an antioxidant and antibacterial. The purpose of this study is to find out the antioxidant and antibakeri activity of kersen leaf extract. The method used for extraction is Microwave Assited Extraction (MAE) with variations in temperature and extraction time. Analysis of antioxidant activity uses the DPPH method by calculating IC50 values while for analysis of antioxidant anctivity using the bland zone method. The results showed that the temperature and time of extraction affect antioxidant and antibacterial activity. The best treatment is obtained from low temperature treatment and extraction time for 7 minutes with IC50 and bland zone values of 44.21 ppm and 11.05 mm respectively.
Analisis Emisi CH4 dan Potensi Energi dari Tempat Pembuangan Akhir (TPA) Muara Fajar 2 Kota Pekanbaru Sasmita, Aryo; Asmura, Jecky; Nurmaida, Betharia
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13284

Abstract

The city of Pekanbaru as an economic center and a destination for urbanization in Riau province has also experienced an increase in population. This is the cause of the increase in the amount of waste that enters the Muara Fajar 2 TPA Pekanbaru City. Solid waste that is stockpiled in the TPA undergoes a degradation process resulting in greenhouse gases in the form of CH4 which contribute to global warming, but have the potential to be utilized as alternative energy. The purpose of this study was to calculate CH4 emissions from landfilling activities at TPA 2 Muara Fajar Pekanbaru City and the potential energy produced. The method for calculating landfill gas emissions uses the IPCC 2019 method. The amount of waste that goes to the TPA in 2011-2020 is obtained from the Pekanbaru City Environment and Forestry Office. The highest estimated values of CH4 gas emissions resulting from landfilling activities at the Muara Fajar 2 TPA Pekanbaru City occurred in 2049 with CH4 emissions of 34,847 Mg/year and CH4 volume of 48,560,479 m3/year. The daily electricity generated is 52,052.84 kWh which can meet the electricity needs of 9,362 households in Pekanbaru City.
Efisiensi dan Fouling Factor Sealtube Heat Exchanger Pada Proses Pendinginan Refined Bleached Deodorized Palm Oil Panjaitan, Jabosar Ronggur Hamonangan; Nurhasanah, Nurhasanah; Atikasari, Laela Febby; Ponilawati, Ponilawati
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13247

Abstract

Refined Bleached Deodorized Palm Oil (RBDPO) is a product of the crude palm oil (CPO) refining process. RBDPO is one of Indonesia's strategic commodities for low price cooking oil production. The cooking oil processing uses a heat transfer device such as heat exchanger. Heat exchanger sealtube 881X is a tool that used in the heat recovery unit at PT. Tunas Baru Lampung, Tbk refinery plant. Heat exchanger sealtube 881X used to cool refined bleached deodorized palm oil (RBDPO) to 95 – 105oC from the deodorization process by utilizing cooling water. In this research, the efficiency and fouling factor of the heat exchanger sealtube 881X were calculated at PT. Tunas Baru Lampung, Tbk refinery plant. Based on the results, it can be seen that the actual efficiency of Heat exchanger sealtube 881X was between 71-87%. Changes in the value of fouling factor affect the thermal efficiency of the heat exchanger sealtube 881X which from the calculation results, the highest fouling factor value was 0.0017.
Model Aplikasi Structural Equation Modelling (SEM) Untuk Kebijakan Profesionalisme Perwira TNI Angkatan Laut Nugroho, Sukmo Hadi; Suharyo, Okol Sri; Chrys, Aang
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13945

Abstract

The development of the Indonesian Navy's strength is carried out through a strategic planning process manifested in four activity programs, namely (1) the Marine Readiness Support Program; (2) Modernization Program for Alutsista and Non-Alutsista as well as the Development of Facilities and Infrastructure for the National Defense for Marine; (3) Professionalism Enhancement Program for Marine Personnel; (4) Marine Management and Operation Implementation Program. The Indonesian Navy realizes that the main strength of all force-building programs lies in the quality of the human resources (HR) possessed by the Indonesian Navy. However, the existing reality reveals various kinds of problems and obstacles that hinder the process of improving the quality of existing human resources. For this reason, the Indonesian Navy seeks to improve the pattern of training for personnel by issuing policies that spur the performance of the personnel development system within the Indonesian Navy. From these problems, a research or modeling is needed that can represent how the influence of the Indonesian Naval Personnel Development Pattern and Indonesian Navy Policy on Officer Professionalism to create superior navy personnel in line with the Indonesian Navy development program towards the World Maritime Axis. The method used in this research is Structural Equation Modeling (SEM). There are 27 indicators consisting of 5 indicators of Angkatan Laut policy variables, 13 indicators of personnel development variables and 9 indicators of professionalism. The results showed that there was a significant direct influence between the Angkatan Laut policy variables on personnel development, personnel development on professionalism and Angkatan Laut policies on professionalism. In addition, there is an indirect influence between Angkatan Laut policies on professionalism through personnel development as a mediating variable.
Studi Gasifikasi Pengembangan Tongkol Jagung dengan Jerami Padi Menggunakan Reaktor Downdraft Dengan Dua Masukan Udara Tekan Irawan, Ibnu; Samlawi, Achmad Kusairi; Budiarto, Hairil
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.12895

Abstract

The production of corn and rice produced by farmers in East Java has the potential to cause agricultural waste, therefore corn cobs are waste that requires special processing in order to be used optimally. Agricultural waste corn cobs and rice straw can be converted into gas fuel (Syngas). The purpose of this study was to determine the performance of gasification seen from the temperature distribution and composition of combustible gases such as CO, H2 and CH4. The downdraft gasifier type is used and applies the AR and E.R ratio to the temperature. For the pyrolysis and oxidation regions, the intake air varies (ARpir-oxi) 80%; 70%; and 0% at 14.5 air intake; 19.3; and 24.1 Nm3/hour from E.R 0.3, 0.4, and 0.5. Air intake in the adjust area using a valve. Temperature measurement using the type K thermocouple. The results show that the maximum temperature using ARpir-oks = 80%, the drying zone temperature is 187°C, the pyrolysis zone is 488°C, the oxidation zone is 895°C and the reduction zone is 585°C. Meanwhile, the highest production of CO gas is 20.50% and H2 gas is 14.55% using an ER of 0.4. Meanwhile, CH4 decreased for all ER values using ARpir-oks = 80%.
Model Gelombang di sekitar Hexagonal Artificial Reef sebagai Submerged Breakwater Menggunakan DUALSPHYSICS Armono, Haryo Dwito; Manurung, Adelbert; Sujantoko, Sujantoko
Rekayasa Vol 15, No 1: April 2022
Publisher : Universitas Trunojoyo Madura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21107/rekayasa.v15i1.13484

Abstract

The functions and uses of artificial reef have evolved from a method of coral reefs restoration to a coastal protection system. Artificial reef can reduce the hydraulic load on the coast to the level required to maintain shoreline balance. Various materials and shape of artificial reefs have been introduced. This paper discussed the wave transmission over hexagonal-shaped artificial reef with 6 holes on each side. The study was conducted using the Smoothed Particle Hydrodynamic (SPH) method integrated in DualSPHysics software to see the effect of gaps between structures with a predetermined configuration to the value of the transmission coefficient (Kt). It was found that the configuration with no gap was able to absorb waves better than the configuration with a gap of 0.15 m and 0.112 m based on the Kt value obtained. In terms of hydrodynamics, it was found that: (1) The increment of the wave steepness, the smaller the Kt value obtained, (2) The larger the wave height, the smaller the Kt value at 0.1 m freeboard depth, while on the freeboard with a depth of 0.2 m and 0.3 m, it was found that the greater the wave height, the greater the Kt value, (3) the increment of the wave period, the Kt were higher, and also (4) the higher the freeboard, the higher the Kt.