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Jurnal Sains dan Teknologi Reaksi
Published by Politeknik Negeri Lhokseumawe
ISSN : 1693248X     EISSN : 25491202     DOI : http://dx.doi.org/10.30811/jstr
Core Subject : Science, Education, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Education Engineering Materials Science & Nanotechnology
Jurnal Sains dan Teknologi Reaksi atau boleh disingkat dengan nama JSTR, berfokus pada banyak Aspek Teknik Kimia, seperti: Teknik Reaksi Kimia, Teknik Kimia Lingkungan, Energi Fosil dan Terbarukan, serta Sintesis dan Pengolahan Material.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 23 Documents
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Search results for , issue "Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI" : 23 Documents clear
ANALYSIS OF COAL QUALITY IMPROVEMENT USING CHEMICAL METHODS FOR MEETS STANDARDS OF CALORIFIC VALUE Nahar, N; Ridwan, R; Irwan, I; Pardi, P
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5423

Abstract

As a country with relatively large coal resources and reserves, Indonesia will face challenges that are not easy in the future. The large amount of coal resources and reserves as well as the continuity of the coal mining industry cannot be ignored. Coal consumption in the world is expected to continue from time to time, especially in the Asian region. Lignite coal reserves account for around 48% of total coal reserves in the world, meanwhile in Asia lignite coal reserves reach 30%, while in Indonesia they reach 60% of total coal reserves. Although the amount of lignite coal consumed accounts for around 30% of total world coal production. The amount consumed in Asia accounts for only 10% of its total coal production. Especially in Indonesia, mining practices tend to tend to be higher quality bituminous and sub-bituminous coal which is more widely mined and produced because producing lignite coal is less economical and cannot meet market criteria. Thus, it can be predicted that what will remain in the future will be a large amount of lignite coal reserves that cannot be utilized. Because the opportunity to fill the potential of the coal market is still wide open, whether used directly as an energy source in power plants or exported abroad, promotion of the use of lignite coal must be made as early as possible as a very important issue for Indonesia. To improve the quality of lignite coal to coal whose quality is like that of anthracite coal so that it can be used, therefore it is necessary to have technology to improve the quality of lignite coal, so the Industrial Innovation Research research will improve the quality of coal using the stirring method by varying the influence of temperature and mixing time. coal, residual oil and kerosene can reduce the water content contained in low rank coal by the adsorption process. The research results show that operating conditions greatly influence the distribution of coal products. Relatively good operating conditions were obtained at a temperature of 200o C and a reaction time of 70 minutes with the results of: oil: 25 ml, water content: 0.668%, ash content: 11.883%, volatile matter: 30.122%, fixed carbon: 57.377%, and calorific value : 6581 Kcal/kg. Key words: Coal; Quality; Kerosene; Calorific Value; Enhancement
ANALYSIS OF THE EFFECT OF PRESSURE AND AIR FLOW RATE ON THE PURITY OF NITROGEN GAS PRODUCTS PRODUCED BY THE PRESSURE SWING ADSORPTION (PSA) METHOD AT PT. ARUN GAS PERTA Jalaluddin, J; Yunus, M; Elfiana, E
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5522

Abstract

ABSTRACTNitrogen is a basic compound in the chemical industry. Nitrogen is an inert gas compound so it is suitable for various applications covering various aspects of manufacturing, processing, handling and shipping chemicals. The aim of this research is to analyze the influence of impurities, pressure and air flow rate on the purity of nitrogen gas products produced using the Pressure Swing Adsorption (PSA) method, then carry out a comparison or simulation of actual field data with Aspen Adsorption V.10. The research method used is descriptive qualitative, the data in this research is field operational data and data collection techniques are carried out periodically through data log sheets. From the research results, it was found that Purity in October to November 2023 on October 5 and 27 was 99.98%, with a flow of 52.2 Nm3/h, while for November there was 98.01% (purity) with flow 105.0 Nm3/h. And after carrying out simulations using Aspen Adsorption V.10 and varying the input data, Purity was obtained at 99.98%, 99.97%, 99.91% with a flow of 100 Nm3/h, 150 Nm3/h, 200 Nm3/h or 0, 4461 kmol/s, 0.6692 kmol/s, 0.8992 kmol/s in Aspen Adsorption V.10 applications.Keywords: Nitrogen, Pressure Swing Adsorption (PSA), Aspen Adsorption, Carbon Molecular Sieve (CMS) 
TESTING CHEMICAL ZINC PHOSPHATE BASE AS A CORROSION INHIBITOR ON CARBON STEEL IN THE CORROSION MEDIA OF COOLING WATER, SEA WATER AND PDAM WATER Sariadi, S; Kenady, Rengga Rahmat; Irwan, I; Zaini, Halim
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5620

Abstract

Zinc phosphate base corrosion inhibitor which aims to determine the effectiveness of the inhibitor to provide protection to carbon steel against the rate of corrosion, with variations in inhibitor concentration at 0, 20, 40 and 60 ppm.This research uses the weight loss method and studies the performance of zinc phosphate base chemical inhibitors in the mediacooling water, sea water and PDAM waterThis is done by carrying out SEM (Scanning Electron Microscopy) testing. The type of steel specimen used in the research is Carbon Steel and deepCorrosion media are cooling water, sea water and PDAM water.The addition of zinc phosphate base carbon steel inhibitor is effective in reducing the corrosion rate of carbon steel in PDAM water and sea water. in sea water media without inhibitors, a drastic reduction in the corrosion rate was seen from 119.0457 mpy to 1.7754 mpy and in PDAM water media without inhibitors, a drastic decrease in the corrosion rate was seen from 18.5873 mpy to 3.4163 mpy, after adding inhibitors with a concentration of 60 ppm. The efficiency of the zinc phosphate base inhibitor in cooling water corrosion media was 30.262% at a concentration of 40 ppm and a soaking time of 20 days. Keywords :Inhibition efficiency, Corrosion Inhibitors, Corrosion in sea water, Corrosion in cooling water, Corrosion Rate, Zinc Phosphate base.
THE EFFECT OF UTILIZING IE KULOH SIRA, IE ASAM SUNTI, AND CORNELA ON THE CHARACTERISTICS OF SILK TOFU Salmyah, S; TA, Cut Fatmawati; Haziri, Ahmad Abrar; Rahmawati, Cut Aja
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5707

Abstract

ABSTRACTSilken tofu is a type of tofu that has a soft and compact texture. Ie kuloh sira and ie acid sunti can be used as coagulants. The lack of this coagulant results in a tofu texture that is not compact. Therefore, cornstarch is added to the making of silken tofu to improve the quality of the resulting silken tofu texture. This study aims to determine the effect of the type and concentration of coagulant and cornstarch concentration on the characteristics of silken tofu and the shelf life of silken tofu. This research method uses the Response Surface Method (RSM) and the organoleptic method. Coagulant concentration (0.5%, 1%, 1.5%, 2%, 2.5%) and cornstarch concentration (5%, 10%, 15%, 20%, 25%). The results obtained for silken tofu with coagulant ie kuloh sira and cornstarch obtained the optimal value, namely at concentrations of ie kuloh sira 2% and cornstarch 10% producing a protein content of 8.45%, texture 4.5 mm/sec. The concentration of ie kuloh sira and cornstarch did not affect the color and aroma of silken tofu, but it did affect the taste of silken tofu. Meanwhile, silk tofu with coagulant ie acid sunti and cornstarch obtained the optimal value, namely at a concentration of 1.5% ie acid sunti and 15% cornstarch producing a protein content of 7.57%, texture 4 mm/sec. The concentration of ie acid sunti and cornstarch has an effect on the color of silken tofu, but has no effect on the aroma and taste of silken tofu. The shelf life of silken tofu with coagulant ie kuloh sira and ie asam sunti only lasted 15 hours at room temperature. Meanwhile, those stored in the refrigerator can last for 3 days with a coagulant ie kuloh sira and 5 days with a coagulant ie acid sunti. Keywords: silken tofu, namely kuloh sira, namely sunti acid, cornstarch, RSM
OPTIMIZATION OF THE USE OF SCANNING ELECTRON MICROSCOPY (SEM) EQUIPMENT IN THE CHEMICAL ENGINEERING DEPARTMENT OF LHOKSEUMAWE STATE POLYTECHNIC Syafari, S
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5736

Abstract

The purpose of this training is to optimize the use of chemical engineering laboratory equipment, namely Scanning Electro Microscopy (SEM), to improve the understanding and experience of students of the Lhokseumawe State Polytechnic, Department of Chemical Engineering. The methods used in this community service activity are intensive training, preparation of efficient usage protocols, and integration of SEM analysis results in research and teaching projects. At the end of this training activity, a question and answer session and assistance in the use of the tool were held to strengthen students' understanding of the training provided. Community service activities on optimizing the use of the Scanning Electro Microscopy (SEM) tool have been running well and optimally, and training participants stated that they were able to operate the tool and understand how to analyze samples using the Scanning Electro Microscopy (SEM) tool. Keywords:Laboratory,SEM,Chemistry,Optimization
OPTIMIZING THE PERFORMANCE OF CHARGE AIR COOLER (CAC) AS A HEAT TRANSFER MEDIUM TO IMPROVE ENGINE RELIABILITY AT PT PLN NUSANTARA POWER UP ARUN Abdi, Faisal; Dewi, Ratni; Yunus, Muhammad
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6149

Abstract

ABSTRACTEquipment performance is one very important thing to be maintained by a company or related agency in order to keep production or work activities running smoothly. Heat Exchanger is a common equipment that we find in many companies and related agencies. Leakage, corrosiveness is common in a heat exchanger or heat exchanger equipment. PT PLN Nusantara Power has a Charge Air Cooler (HE) as a heat exchanger medium between air for the combustion process and cooling water in each engine to help the electricity production process. For this reason, this analysis aims to see the reliability of engines 1 to 10 seen from the ratio of the effectiveness value of the calculation results to the effectiveness value of the commissioning results and compare the operational parameters in the field with the results of the hysys simulation. From the results of the calculation analysis, the highest effectiveness value on engine 3 was 92.759 % which was influenced by the ratio of the actual heat transfer rate value compared to the maximum heat transfer rate value. This result is of course as expected where the effectiveness value of the air cooler charge must be greater than 90%. Similar to engine 3, the other nine engines also have an effectiveness value of 90%, meaning that in terms of performance the charge air cooler is still able to work optimally. In the input of hysys simulation data, a difference in data between the incoming air temperature data from the data input in hysys and operational data in the field was obtained. This can be caused by the large value of the discharge of the two flows, readings in the field, as well as the need for calibration data in the field for the reading of equipment performance indicators such as flow indications, pressure indicators, temperature indicators, and so onKeywords : Engine, Corrosion, Heat exchanger, effectiveness, hysys
CREATION OF LOCAL MICROORGANISMS (MOLES) WITH THE USE OF HOUSEHOLD VEGETABLE WASTE AS A STARTER/DECOMPOSER FOR COMPOST FERTILIZER MAKING Mukarramah, Cut; Harunsyah, H; Nahar, N
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6145

Abstract

ABSTRACTLocal Microorganisms (MOL) are microorganisms made from natural materials as a medium for the development of microorganisms that are useful for accelerating the destruction/decomposition of organic matter (the process of decomposition into compost/organic fertilizer). In addition, it can also function as additional nutrients for plants, Local Microorganisms contain macro and micro nutrients and also contain microbes that have the potential to be a catalyst for organic matter, growth stimulants and as plant disease pest control agents. Based on the content contained in the MOL, MOL can be used as a decomposer, biofertilizer, and as an organic pesticide. This type of research is an experiment, by making a formulation of MOL solution based on the content/concentration of coconut water in the MOL solution, the bacterial content in the sample based on laboratory testing of Samples 1.2 and 3 with values (3.57 x 106 CFU/ml, 3.86 x 106 CFU/ml and 3.94 x 106 CFU/ml). The purpose of making the formulation of MOL solution in this study is to see the effectiveness of local microorganisms (MOL) in accelerating/shortening the time of the decomposition process of organic waste in making compost, the fastest decomposition value/time in samples 1-4 with the amount of stsrter/decomposer solution used 1 liter requires a decomposition time of 5 weeks.Keywords: Local Microorganisms, Starter/Decomposer, Compost Fertilizer
ANALYSIS OF COAGULANT NEEDS AND OPERATIONAL COSTS IN THE WATER PURIFICATION PROCESS ON CLARIFIER (Z-9451) IN THE UTILITY UNIT OF PT PERTA ARUN GAS LABORATORY SCALE USING THE JAR TEST METHOD Mahrizal, M; Elfiana, E; Pardi, P
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6146

Abstract

ABSTRACTThis study discusses the analysis of coagulant needs and operational costs in the water purification process on the clarifier (Z-9451) in the utility unit of PT Perta Arun Gas on a laboratory scale using the jar test method. This research is expected to provide benefits in improving the efficiency of chemical use, producing water quality that meets standards and estimating operational costs. This study aims to test the effectiveness of coagulants using jartest on clarifier inlet water samples at PT Perta Arun Gas. The parameters tested include pH, turbidity, and conductivity. Experiments were carried out with variations in the doses of coagulants and polymers. The results of the experiment will be used to determine the optimal dose of coagulant for raw water treatment. The best efficiency In the first week of November 7, 2023, the results of the analysis of the clarifier feed raw water (Z-9451) were obtained, namely a decrease in turbidity of 98.74%. In the second week of November 14, 2023, the decrease in turbidity was 98.42%, in the third week of November 21, 2023, the decrease in turbidity was 98.33%, and in the last week of November 28, 2023, the decrease in turbidity was 98.50%. The results showed the best efficiency in the first week with a concentration of aluminum sulfate of 24 ppm and polymer 0.20 ppm. The use of this concentration is able to produce good water quality and save the company's operational costs. However, weather conditions can affect the quality of raw water, so further research is needed to obtain the optimal conditions for the addition of aluminum sulfate and polymer. It is recommended to conduct a weekly Jartes analysis in order to provide recommendations on the use of aluminum sulfate and polymers as coagulants in utility units. Keywords : Aluminium Sulfat, Clarifier , Jartest, Koagulan, Polymer, Turbidity
ENGINE 5 FUEL RATIO OPTIMIZATION WITH LOAD FEEDBACK CORRECTION USING VAMPSET SOFTWARE TO REDUCE SPECIFIC GAS CONSUMPTION (SGC) AT PT PLN NUSANTARA POWER ARUN GENERATION UNIT Yusrizal, Y; Zulkifli, Z; Rihayat, R
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6147

Abstract

ABSTRACTFuel Ratio Optimization with 3% Load Feedback Correction to Reduce Specific Gas Consumption (SGC) at PLTMG Arun is a test in the field of power plants that focuses on optimizing the SGC Engine of PLTMG by looking for a fuel mixture composition that produces optimal efficiency of the generating engine and is safe for the reliability of the plant. In 2023, the SGC target is 8600 BTU/kWh. The highest SGC value of one of the engines in 2023 is in Engine 5 of 9327.27 BTU/kWh with an average exhaust gas temperature of 528°C, while the lowest SGC value in Engine 10 is 8,481 BTU/kWh with an average exhaust gas temperature of 532°C. The difference in exhaust gas temperature shows that there is an unused potential for heat energy in engine 5, causing a significant difference in SGC. This test aims to optimize the combustion point using a structured method calculation reference, maintain the engine exhaust gas temperature in accordance with the commissioning limits, lower the SGC and increase efficiency, then it will be obtained as a reference as the basis for changes from the AFR. For AFR tuning from the initial condition, i.e. load feedback = load output generator, it will then be converted to load feedback load output generator. The method used is to use the load feedback correction method by modifying the analog value scale of the output of the Power Monitoring Unit (PMU) from the initial condition of 4-20 mA = 0-12000 kW to the modified condition of 4-20 mA = (0-(12000+x%) kW, where this condition adjusts from the allowable combustion results according to the lean burn diagram from the manufacturer. From the implementation in October 2023, the SGC value decreased from the previous 9327.27 BTU/kWh to 9177.87 BTU/kWh. In addition, there was an increase in plant efficiency from 36.54% to 37.14, an increase in EAF from 98.34% to 98.91%, a decrease in EFOR from 1.37% to 0.09% and a decrease in GPHR from 2350,473 Kcal/KWh to 2312,673 Kcal/KWh.keyword: Engine, fuel ratio, specific gas consumption, commissioning, load feedback, efisiensi, exhaust gas temperature.
CALCULATING THE NUMBER OF GAS PILOTS AND LNG CIRCULATING IN THE MABOG LINE (MARINE BOIL OF GAS) COOLING SYSTEM AT PT. PERTA ARUN GAS Birri, Chairul; Sariadi, S; Elwina, E
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6144

Abstract

ABSTRACTAlong with the development of PT. Perta Arun Gas, the challenges to refinery operations also have a significant impact, the company is expected to be able to minimize even the slightest losses that may occur during the industrial process. One of them is that in the flow of the LNG distribution (loading) process to ships, the formation of Boil-Off Gas (BOG) as a result of the expansion in the loading room is inevitable. So that the BOG that forms must be eliminated so as not to cause overpressure in the ship's tank, the B-6803/4 marine flare facility is available to burn the formed BOG so as not to pollute the environment if the gas is directly discharged into the atmosphere. The main tool in this recovery system is the Atomizer, which aims to reduce the temperature of the BOG by atomizing a certain amount of LNG with pressurized vapor gas into the BOG input flow so that heat transfer occurs so that it is in accordance with the specifications of the compressor feed temperature. After a series of calculations, it was found that the total LNG and gas buffer needed to be able to cool the MaBOG line during the loading process with an estimated time of 12.3 hours was 305.6 m3 for LNG and as much as 0.069 mmscfd for gas buffer. This need is in the background with the adjustment of the outlet temperature setting of the second section atomizer (V 6805/13-24) is -140 °C and with the input temperature in HV-68108 which is -80 °C. In addition, after obtaining a calculation model to obtain the value of LNG and gas buffer requirements, the author also tried to conduct some systematic analyses on the influence of LNG and gas buffer requirements on changes in BOG inlet temperature using MS. Excel.keyword : LNG, Boil-Off Gas, Buffer Gas

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