Article Per Year (5 Year)
p-Index From 2020 - 2025
0.751
P-Index
This Author published in this journals
All Journal Jurnal Serambi Engineering Jurnal Sains dan Teknologi Reaksi Jurnal Teknologi
Dewi, Ratni
Politeknik Negeri Lhokseumawe
Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Education Electrical & Electronics Engineering Engineering Environmental Science Materials Science & Nanotechnology Mechanical Engineering

Published : 8 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 8 Documents
Search

 1 
KINERJA REAKTOR UREA DC-101 DI PT. PUPUK ISKANDAR MUDA Wahidin, Teuku Raja; Dewi, Ratni; Yunus, Muhammad
Jurnal Sains dan Teknologi Reaksi Vol 11, No 2 (2013): Jurnal Sains dan Teknologi Reaksi
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v11i2.180

Abstract

PT. Pupuk Iskandar Muda mempunyai dua unit pabrik yaitu PIM 1 dan PIM 2. Bahan baku yang digunakan untuk memproduksi pupuk urea adalah dengan mereaksikan NH3 dan CO2 pada kondisi tekanan dan temperatur yang sangat tinggi. Tempat terjadinya reaksi antara NH3 dan CO2 tersebut adalah di dalam reaktor (DC-101). Dari hasil perhitungan diperoleh konversi reaksi pada reaktor PIM 1 adalah 72,6 %, sedangkan reaktor PIM 2 adalah 74,2 %. Hal tersebut menunjukkkan bahwa kondisi konversi reaksi pada kedua reaktor masih tergolong bagus karena pada kondisi disain persen konversi reaksi yang diharapkan adalah 75 %. Untuk neraca energi, reaktor PIM 1 Qloss yang terjadi adalah 1,008 % sedangkan untuk reaktor PIM 2 Qloss yang terjadi adalah 39,5 %,Kata kunci : CO2, Konversi reaksi, NH3, Qloss, Reaktor
PEMANFAATAN TANAH GAMBUT SEBAGAI ADSORBEN PENYISIHAN SENYAWA AMMONIA DALAM LIMBAH CAIR INDUSTRI TAHU Dewi, Ratni; Sari, Ratna
Jurnal Sains dan Teknologi Reaksi Vol 5, No 2 (2007): Jurnal Sains dan Teknologi Reaksi
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v5i2.41

Abstract

Kehadiran ammonia dalam limbah industri dapat menimbulkan masalah bagi lingkungan, khususnya kehidupan akuatik. Untuk mengatasi hal tersebut perlu dilakukan pengolahan terlebih dahulu sebelum dibuang ke badan air. Salah satu metode pengolahan tersebut adalah melalui proses adsorpsi. Tujuan penelitian ini adalah menggunakan tanah gambut sebagai adsorben untuk menyisihkan ammonia pada limbah cair industri tahu. Pada penelitian ini menggunakan sistem operasi batch. Sebelum digunakan sebagai adsorben, tanah gambut dipanaskan pada variasi temperatur, yaitu 105 0C, 300 0C, dan 450 0C. Selain temperatur, dilakukan juga variasi waktu kontak selama proses adsorpsi berlangsung, yaitu 2 jam, 4 jam, 6 jam, 8, jam, dan 24 jam. Dari hasil penelitian dihasilkan kondisi yang paling baik yaitu pada temperatur pemanasan 3000C dan 4500C dengan waktu kontak 24 jam. Sedangkan efisiensi penyisihan yang dicapai berkisar 83%-86% dengan konsentrasi awal air limbah sebesar187,745 ppm.Kata Kunci : ammonia, tanah gambut, adsorpsi, adsorben, limbah tahu
KAJIAN PENGGUNAAN METODE ELEKTROKOAGULASI UNTUK PENYISIHAN COD DAN TURBIDITI DALAM LIMBAH CAIR PABRIK KELAPA SAWIT Dewi, Ratni
Jurnal Sains dan Teknologi Reaksi Vol 7, No 2 (2009): Jurnal Sains dan Teknologi Reaksi
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v7i2.118

Abstract

Limbah perkebunan khususnya limbah cair PKS umumnya mengandung COD dengan kadar di atas 12.000 ppm, untuk itu limbah ini harus diolah terlebih dahulu sebelum dibuang ke badan air. Pada penelitian ini dikaji penggunaan metode elektrokoagulasi untuk menyisihkan kadar COD dan Turbiditi dari air limbah PKS yang digunakan. Tegangan listrik dan waktu kontak divariasikan, mulai 3 - 12 volt, serta waktu 30 menit – 120 menit. Elektroda yang digunakan terdiri atas 3 jenis, yaitu : sepasang elektroda Al. Elektroda besi dan gabungan keduanya. Hasil penelitian menunjukkan bahwa dengan penggunaan elektroda Al memberikan penyisihan COD dan turbiditi yang paling besar yakni 87 % dan 91 % pada waktu kontak 120 menit dan tegangan 12 volt. Dari ketiga variabel penelitian diperoleh waktu kontak, tegangan listrik, dan jenis elektroda sangat mempengaruhi proses elektrokoagulasi.Kata Kunci : Pabrik kelapa sawit, Elektrokoagulasi, Elektroda, Aluminium, Besi
PENINGKATAN OKSIGEN TERLARUT (AERASI) DENGAN MENGGUNAKAN PIPA – U Dewi, Ratni; Sari, Ratna
Jurnal Sains dan Teknologi Reaksi Vol 1, No 2 (2003): Jurnal Sains dan Teknologi Reaksi
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v1i2.64

Abstract

Water is an essential substance in the human daily life. One of the criteria of healthy water is represented by its dissolved oxygen content. In this research, the water used came from the drilled well and after being treated hopefully the dissolved oxygen in the water will increase. Dissolved oxygen contained in water originated from the air and from the photosynthesis process of water plants. The capability of oxygen to dissolve in water are effected by temperature, barometric air pressure or high and the mineral content in the water. This research‘s goal is to anylize dissolved oxygen content in the water after being treated to several different variables such as pipe length, air flow velocity and water flow velocity. From the interaction of these variable we will find which variable is most significant. The outcome of the the research show that air flow velocity has an influence on the dissolved oxygen content in which the higher the air flow velocity, dissolved oxygen in the water is increase. Water flow velocity has a significant influence on dissolved oxygen content where the lower the water flow velocity will increase the dissolved oxygen in the water.Key Word : Dissolved Oxygen
Pembuatan Grafena dengan Metode Reduksi Graphene Oxide Menggunakan Bahan Baku Grafit dan Reduktor Natrium Hipopospit Ratna Sari; Cut Dina Mastura; Teuku Rihayat; Ratni Dewi; Lukman Hakim
Jurnal Serambi Engineering Vol 7, No 2 (2022): April 2022
Publisher : Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32672/jse.v7i2.4211

Abstract

One of the new materials that has developed recently is graphene. Graphene is a new closed, strongest, and superior material in the world today which is formed from a single layer of carbon atoms which has a hexagonal structure resembling a honeycomb. This study aims to determine the effect of graphite size on the quality of graphene produced using the graphene oxide reduction method. This method uses sodium hypophosphite reductor and oxidizing agent KMnO4, sulfuric acid and hydrogen peroxide. The quality of graphene is observed by looking at the electrical conductivity produced. This study varied the size of the graphite (106 µm, 125 µm, 150 µm, 180 µm dan 250 µm) and the reductor volume variation (3 ml, 5 ml, 7 ml, 9 ml dan 11 ml). The graphene oxide solution was heated in hot water and then filtered, ultrasonically for 3 hours, and in the oven for 6 hours at 80oC. From the results of the electrical conductivity test, the best results were obtained at a graphite size of 106 µm while for the volume of the reductor the best results were at 11 ml. Graphene was characterized using FTIR (Fourier transform infrared) and SEM (scanning electron microscope). The results of the characterization of the powder samples show that there has been a change in the structure of graphite to graphene. The size of the graphite and the volume reducing agent has a significant effect on the graphene’s electrical conductivity.
Produksi Gas Hidrogen dari Air Laut Menggunakan Proses Photovoltaic-Electrolysis dengan Katalis H2SO4 Lukman Hakim; Elma Agustina Berutu; Ratna Sari; Ratni Dewi
Jurnal Serambi Engineering Vol 8, No 1 (2023): Januari 2023
Publisher : Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32672/jse.v8i1.5575

Abstract

AbstractHydrogen is a new and renewable energy that has advantages over other energies. Among the hydrogen gas production methods that have the potential to be developed is seawater electrolysis, which is an abundant source. The electrolysis method uses a Direct Current (DC) electric current source. In this study, DC electric current was used from the results of solar panels (photovoltaic) with a volume of seawater as an electrolyte solution of 3500 ml. The electrolysis process times were 15, 30, 45, and 60 minutes using graphite electrodes with variations in voltages of 5, 10, 15 and 20 volts and H2SO4 catalyst concentrations of 0.1M, 0.25M, 0.5M and 0.75M at ambient conditions and 1 atm. The study results showed that the voltage and catalyst concentration of H2SO4 showed the effect of the formation of hydrogen gas. Where the effect of the loading voltage is reversed with the catalyst concentration of H2SO4. The higher voltage, the flow rate of the hydrogen gas produced also increases and the higher the concentration of H2SO4 catalyst used, lower the flow rate of the hydrogen gas produced. Based on the research results, the highest hydrogen gas flow rate was obtained at a catalyst concentration of 0.1M H2SO4, at a voltage of 20 volts with a flow time of 60 minutes, a flow rate of 20.5 ml/minute and in seawater electrolysis using H2SO4 catalyst did not produce NaOCl as a byproduct.Keywords: electrolysis, energy, graphite, hydrogen, catalyst
Studi Kasus Pengaruh Perbedaan Spesifikasi Fuel Gas terhadap Kinerja Pembakaran Thermal Oxidizer Unit di PT X Muhammad Fiqih Alif Utama; Ratni Dewi; Sariadi Sariadi
Jurnal Teknologi Vol 23, No 2 (2023): Oktober 2023
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/teknologi.v23i2.4334

Abstract

Fuel gas is a term used by the industry to refer to fuel in physical form or gas form. The type of fuel used in the thermal oxidizer at the Sulfur Recovery Unit (SRU) plant is fuel gas. The thermal oxidizer is a device that functions to oxidize residual H2S, elemental sulfur, and CO2 derived from the sour gas purification process. Currently, the reliability of the thermal oxidizer in operation needs special attention by management and the operations team because the ability of the refractory in the Thermal Oxidizer unit to maintain combustion heat is not optimal and stable so the combustion heat has touched the thermal oxidizer at several points to cause cracks and leaks. The purpose of this study is to analyze the effect of differences in fuel gas specifications on combustion performance and heat energy formed in the thermal oxidizer unit, to analyze the effect of differences in fuel gas specifications on increasing the operating temperature and reliability of the thermal oxidizer and to analyze the impact of the risk of implementing different gas usage on operations at the SRU plant. The method used in the research is causal comparative where observations are made of data from factors that are thought to be the cause as a comparison of differences in the use of fuel gas. In this study LP fuel gas is the best fuel usage option because it is more efficient and controlling the risk level can be done optimally with the use of LP fuel gas.
Produksi Gas Hidrogen dari Air Laut Menggunakan Proses Photovoltaic-Electrolysis dengan Katalis H2SO4 Lukman Hakim; Elma Agustina Berutu; Ratna Sari; Ratni Dewi
Jurnal Serambi Engineering Vol 8, No 1 (2023): Januari 2023
Publisher : Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32672/jse.v8i1.5575

Abstract

AbstractHydrogen is a new and renewable energy that has advantages over other energies. Among the hydrogen gas production methods that have the potential to be developed is seawater electrolysis, which is an abundant source. The electrolysis method uses a Direct Current (DC) electric current source. In this study, DC electric current was used from the results of solar panels (photovoltaic) with a volume of seawater as an electrolyte solution of 3500 ml. The electrolysis process times were 15, 30, 45, and 60 minutes using graphite electrodes with variations in voltages of 5, 10, 15 and 20 volts and H2SO4 catalyst concentrations of 0.1M, 0.25M, 0.5M and 0.75M at ambient conditions and 1 atm. The study results showed that the voltage and catalyst concentration of H2SO4 showed the effect of the formation of hydrogen gas. Where the effect of the loading voltage is reversed with the catalyst concentration of H2SO4. The higher voltage, the flow rate of the hydrogen gas produced also increases and the higher the concentration of H2SO4 catalyst used, lower the flow rate of the hydrogen gas produced. Based on the research results, the highest hydrogen gas flow rate was obtained at a catalyst concentration of 0.1M H2SO4, at a voltage of 20 volts with a flow time of 60 minutes, a flow rate of 20.5 ml/minute and in seawater electrolysis using H2SO4 catalyst did not produce NaOCl as a byproduct.Keywords: electrolysis, energy, graphite, hydrogen, catalyst
Co-Authors Cut Dina Mastura Elma Agustina Berutu Lukman Hakim Muhammad Fiqih Alif Utama Muhammad Yunus Ratna Sari Ratna Sari Sariadi Sariadi Teuku Rihayat Wahidin, Teuku Raja