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"The book consists of two parts. The first part provides basic information about normal concrete, its grades used on sites and various kinds of modified concretes such as fiber-reinforced concrete, sulphur concrete, roller compacted concrete, high performance concrete, ultra- high performance concrete, and flowing concrete. . It further addresses physical properties of concrete and various types of Portland cement, blended cements, admixtures, additives including properties of aggregates and their influence. The second part of the book highlights the principal causes of concrete deterioration along with protective measures, resulting from incorrect selection of constituent materials, poor construction methods, external factors, chemical attack, corrosion problems, hot and cold weather effects, and the various errors in designing and detailing. Featuring an extensive bibliography of the highly adopted standards as well as manuals and journals critical to the construction industry at the end of each chapter, the volume offers readers an advanced understanding of the theory and practical application of concrete technology and international standards in North America and Britain."

"Teknologi proses Thiopaq rencananya akan dikembangkan pada lapangan gas alam X. Proses Thiopaq merupakan teknologi terintegrasi untuk pemrosesan gas yang efisien dan ramah lingkungan karena menggunakan bakteri dari alam. Input proses Thiopaq adalah acid gas 3 MMSCFD dengan kandungan hidrogen sulfida mencapai 12% mol berhasil memperoleh kembali sulfur lebih dari 94%. Kadar H2S pada gas buang dapat diturunkan hingga 0 ppm. Kapasitas produksi sulfur 13 ton per hari. Dengan menggunakan proses Thiopaq, apabila harga sulfur sebesar 500 USD/ton maka didapatkan IRR sebesar 33%, harga NPV sebesar USD 53.237.964 dan PBP selama 2,35 tahun. Semakin tinggi harga sulfur maka revenue akan semakin meningkat dan mengakibatkan naiknya nilai NPV dan IRR sedangkan nilai PBP semakin rendah yang berarti bahwa waktu yang diperlukan untuk mencapai angka nol (titik balik modal) akan semakin cepat. Dan analisis sensitivitas menunjukan bahwa harga sulfur yang paling berpengaruh terhadap terjadinya perubahan NPV dan IRR.

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Thiopaq process technology will be developed in the field of natural gas X. Thiopaq is an integrated process technology for gas processing. It is an efficient and friendly environmental because of using the natural bacteria. Feed stream of Thiopaq process is acid gas 3 MMSCFD with hydrogen sulfide 12% mole able to recover sulphur more than 94%. Level of hydrogen sulfide in flue gas can be reduced to 0 ppm. The production capacity is 13 ton per day of sulfur. By using technology Thiopaq, when the sulphur price of 500 USD/ton, it will obtain 33% of IRR, the price of NPV USD 53.237.964 and PBP of 2,35 years. The higher price of sulphur will also increase the amount of revenue and lead to the higher NPV and IRR. The lower value of PBP means the required time to reach zero (turning point of the capital) will be faster. And the sensitivity analysis of the increasing of sulfur price will have a significant influence in the NPV and IRR."

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Batu bara merupakan salah satu sumber energi yang bernilai ekonomis dibandingkan energi lainnya. Diperlukan kegiatan eksplorasi untuk mendapatkan cadangan batu bara. Daerah penelitian dilakukan pada lapangan Banko Barat PIT X PT. Bukit Asam, Tbk., Tanjung Enim, Sumatera Selatan. Batu bara pada daerah penelitian berada pada Formasi Muara Enim. Penelitian ini bertujuan untuk mengetahui estimasi sumber daya batu bara, persebaran kualitas bara, dan kegunaan dari batu bara. Metode penelitian yang dilakukan adalah menganalisis data lubang bor, logging geofisika, dan kualitas batu bara. Dari analisis yang dilakukan dapat diketahui bentuk pemodelan 3D, estimasi sumber daya batu bara, persebaran kualitas batu bara, dan kegunaan batu bara. Pemodelan 3D dan estimasi yang dilakukan menggunakan aplikasi Minescape 5.7. Estimasi Sumber daya pada daerah penelitian pada sumber daya terukur sebesar 109.977.726 ton, Sumber daya tertunjuk 4.091.138 ton, dan Sumber daya terukur 15 ton. Peringkat batu bara pada daerah penelitian termasuk kedalam High Volatile Bituminous B. Dari analisis persebaran kualitas batu bara pada daerah penelitian dipengaruhi oleh lingkungan pengendapan dan tingkat sedimentasi. Daerah penelitian termasuk kedalam tipe rawa raised swamp dan dipengaruhi oleh pengaruh air laut dilihat dari tingginya nilai kandungan sulfur pada seam C1. Nilai kandungan kalori pada daerah penelitian dipengaruhi oleh nilai kandungan abu, kelembapan, fix carbon, dan zat terbang. Nilai kandungan kalori dianalisis menggunakan regresi linear. Didapatkan nilai x yang positif pada nilai zat terbang dan fix carbon yang mengindikasikan nilai yang berbanding lurus sedangkan pada nilai kelembapan dan kandungan abu didapat nilai x yang negatif yang mengindikasikan nilai berbanding terbalik. Dari hasil analisis tersebut dapat ditentukan kegunaan batu bara pada daerah penelitian. Batu bara pada daerah penelitian dapat digunakan sebagai pembangkit listrik dan industrik semen.

 

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Coal is a source of energy that has economic value compared to other energies. Exploration activities are required to obtain coal reserves. The research area was conducted in the West Banko field PIT X PT. Bukit Asam, Tbk., Tanjung Enim, South Sumatra. Coal in the research area is in the Muara Enim Formation. This study aims to determine the estimation of coal resources, distribution of coal, and usefulness of coal. The research method used are to analyze borehole data, geophysical logging, and coal quality. From the analysis, it can be seen the form of 3D modeling, estimation of coal resources, distribution of coal quality, and use of coal. 3D modeling and estimation were carried out using Minescape 5.7. Estimated resources in the research area at measured resources were 109,977,726 tons, indicated resources were 4,091,138 tons, and measured resources were 15 tons. The rank of coal in the study area is High Volatile Bituminous B. From the analysis of the distribution of coal quality in the study area is influenced by the depositional environment and sedimentation. The research area is raised swamp and influenced by sea water seen from the high value of sulphur content in seam C1.The value of the calorific content in the study area is influenced by the value of the volatile matter, moisture, fix carbon, and ash. Calorific values were analyzed using linear regression. From the linear regression obtained a positive x value of ash and fix carbon which indicates a value that is directly proportional and a negative x value of ash and total moisture which indicates a value that is inversely proportional. From the results of this analysis, it can be determined the use of coal in the study area. Coal in the research area can be used as a power plant and cement industry.

 

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"Penelitian ini mengkaji pengaruh penambahan natrium sulfat dan sulfur terhadap reduksi karbotermik selektif pada ilmenit dan bimomassa. Telah direduksi sebanyak tiga belas sampel dengan variasi persentase penambahan aditif dengan kenaikan 1,5%, jenis ilmenit dan lama waktu milling. Reduktor yang digunakan yaitu bimoassa dari pulverized cangkang kelapa sawit, sedangkan CMC sebagai binder. Sampel direduksi pada temperatur 120oC pada kondisi inert selama 60 menit. Berdasarkan karakterisasi XRD, diperoleh fasa dominan yaitu besi dan ferros-pseudobrookite.  Hasil uji SEM memperlihatkan agregasi dan pertumbuhan partikel besi lebih baik dengan penambahan natrium sulfat daripada sulfur, dan waktu proses mechanochemical yang lama. Berdasarkan analisa Image-J diperoleh nilai tertinggi untuk luas rata-rata yaitu 73,78 mm2 pada penambahan natrium sulfat. Sedangkan nilai tertinggi dengan penambahan sulfur yaitu 36,57 mm2. Selain itu, nilai recovery dan kadar pada Fe dan Ti dibedakan pada fasa metalik dan fasa terak. Untuk nilai recovery dan kadar Ti bukan dalam bentuk logam akan tetapi dalam fasa bentuk fasa TiO2, FeTiO3, FeTi2O5, dan MgTi2O5. Pada fasa metalik, nilai tertinggi recovery (%) Fe dan Ti berturut-turut yaitu 92,82 dan 22,46. Sedangkan untuk nilai kadar (%) Fe dan Ti berturut-turut yaitu 94,20 dan 18,91. Disisi lain, pada fasa terak, nilai tertinggi recovery (%) Fe dan Ti berturut-turut yaitu 42,00 dan 98,51. Sedangkan untuk nilai kadar (%) Fe dan Ti berturut-turut yaitu 17,33 dan 70,45.

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This study examined the effect of adding sodium sulfate and sulfur to selective carbothermic reduction on ilmenite and biomass. Thirteen samples have been reduced by adding additive doses with an increase of 1.5%, ilmenite type and length of milling time. The reductors used are biomass from pulverized palm oil shell, while CMC is a binder. Samples were reduced at a temperature of 1200oC in an inert condition for 60 minutes. Based on XRD characterization, the dominant phase is iron and ferros-pseudobrookite. The SEM test results show that the aggregation and growth of iron particles is better with the addition of sodium sulfate than sulfur, and the long process time of the mechanochemical process. Based on Image-J analysis, the highest value for the average area was 73.78 mm2 for the addition of sodium sulfate. While the highest value with the addition of sulfur is 36.57 mm2. In addition, the recovery and grade in Fe and Ti are distinguished from the metallic phase and the slag phase. For recovery and grade of Ti not in metal form but in phase form phase TiO2, FeTiO3, FeTi2O5, and MgTi2O5. In the metallic phase, the highest recovery (%) in Fe and Ti were 92.82 and 22.46, respectively. Whereas for the grade (%) in Fe and Ti 94.20 and 18.91, respectively. On the other hand, in the slag phase, the best recovery (%) in Fe and Ti were 42.00 and 98.51, respectively. Whereas for the grade of (%) Fe and Ti 17.33 and 70.45, respectively."

"Kandungan senyawa sulfur pada bahan bakar Biosolar dapat menyebabkan berbagai dampak buruk seperti kerusakan mesin. Kadar sulfur pada bahan bakar Biosolar di Indonesia masih sangat tinggi sehingga perlu diturunkan untuk memenuhi regulasi internasional dan meningkatkan efisiensi penggunaan mesin diesel. Penelitian ini bertujuan untuk menurunkan kadar sulfur dengan menghilangkan senyawa sulfur aromatik pada bahan bakar Biosolar menggunakan metode Oxidative desulfurization (ODS). Hidrogen peroksida (H2O2) digunakan sebagai oksidator dengan katalis molibdenum oksida sebagai inti aktif berpenyangga gamma alumina (MoO3/γ-Al2O3). Proses ODS dilakukan pada wadah berpengaduk pada suhu 40°C sampai 70°C dengan loading inti aktif katalis 5% sampai 20%, waktu oksidasi 15 menit sampai 60 menit, dan rasio molar oksidator dengan sulfur (O/S) 90:1 sampai 240:1. Setelah proses oksidasi, senyawa sulfur dalam Biosolar berubah menjadi senyawa sulfone kemudian dipisahkan dari Biosolar menggunakan metode sentrifugasi. Kandungan senyawa sulfur pada Biosolar setelah melewati proses ODS dianalisis menggunakan metode FTIR. Nilai desulfurisasi terbaik pada penelitian ini didapat pada suhu 50°C, loading inti aktif katalis 10%, waktu reaksi oksidasi 30 menit, dan rasio O/S 120:1 dengan desulfurisasi sebesar 7,7%.

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The content of sulfur compounds in biodiesel fuel can cause various bad effects such as diesel engines damage. Sulfur content in biodiesel fuel in Indonesia is still very high, so it needs to be reduced to meet international regulations and improve the efficiency of diesel engines. This study aims to reduce sulfur content by removing aromatic sulfur compounds in biodiesel fuel using Oxidative desulfurization (ODS) method. Hydrogen peroxide (H2O2) will be used as an oxidizing agent with molybdenum oxide as an active core supported by gamma alumina (MoO3/γ-Al2O3). The ODS process is carried out in a stirred vessel at a temperature of 40 to 70°C with an active catalyst loading from 5 to 20%, oxidation time 15 to 60 minutes, and molar ratio of oxidator with sulfur (O/S) 90:1 to 240:1. After the oxidation process, the sulfur compounds in the biodiesel will turn into sulfone compounds which will be separated using the centrifugation method. The content of sulfur compounds in biodiesel after passing through the ODS process will be analyzed using the FTIR method. The best desulfurization rate in this study was obtained at temperature of 50°C, 10% active catalyst loading, oxidation reaction time of 30 minutes, and O/S ratio of 120:1 with desulfurization of 7.7%."

"Batubara pada site Gurimbang PT Berau Coal Kecamatan Sambaliung, Kabupaten Berau, Kalimantan Timur dianalisis berdasarkan pengamatan makroskopis, metode analisis petrografi organik dan analisis nilai sulfur untuk mendapatkan karakteristik dan peringkat batubaranya. Berdasarkan hasil analisis pengamatan makroskopis, dapat diketahui bahwa seam K, KU, KL memiliki ciri berwarna hitam kecokelatan dengan cerat cokelat, memiliki bentuk sub-conchoidal sampai conchoidal, kekerasan moderately hard-hard, kilap kusam, banyak ditemukan jejak resin serta mineral pirit. Berdasarkan hasil analisis petrografi maseral, seluruh sampel didominasi oleh maseral vitrinite sebanyak 83.8-94.4%, maseral liptinite sebanyak 3.2%-11.2% dan maseral inertinite sebanyak 1.3%-4.2%. Berdasarkan hasil analisis petrografi mineral, seluruh sampel didominasi oleh mineral clay dengan jumlah 0.30% – 1.60% pada sampel yang berbeda. Berdasarkan analisis nilai sulfur, seam KU memiliki kandungan sulfur dengan nilai tertinggi 2.58% dan terendah 0.41% dan dapat digolongkan ke dalam batubara high sulphur, sedangkan seam KL memiliki kandungan sulfur dengan nilai tertinggi 0.4% dan terendah 0.11% dan dapat digolongkan ke dalam batubara low sulphur. Berdasarkan hasil pengukuran reflektan dapat disimpulkan semua sampel yang ada termasuk ke dalam rank batubara lignit sampai dengan sub-bituminus C berdasarkan klasifikasi ASTM D 388-05. Berdasarkan perhitungan TPI dan GI, sampel terendapkan pada lingkungan pengendapan lower delta plain hingga upper delta plain dengan sublingkungan pengendapan telmatik dan limno-telmatic pada rawa gambut wet forest swamp dan fen.

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Coal at the Gurimbang site of PT Berau Coal, Sambaliung District, Berau Regency, East Kalimantan was analyzed based on macroscopic observations, organic petrographic analysis methods and analysis of sulfur values to obtain the characteristics and rank of the coal. Based on the results of the macroscopic observation analysis, it can be seen that the K, KU, KL seams have a characteristic black-brown color with brown streaks, have a sub-conchoidal to conchoidal shape, moderately hard-hard hardness, dull luster, many traces of resin and pyrite minerals are found. Based on the results of maseral petrographic analysis, all samples were dominated by vitrinite maceral as much as 83.8-94.4%, liptinite as much as 3.2%-11.2% and inertinite as much as 1.3%-4.2%. Based on the results of mineral petrographic analysis, all samples were dominated by mineral clay with an amount of 0.30% - 1.60% in different samples. Based on the sulfur value analysis, seam KU has a sulfur content with the highest value of 2.58 and the lowest 0.41 and can be classified as high sulfur coal, while seam KL has a sulfur content with the highest value of 0.4 and the lowest 0.11 and can be classified as low sulfur coal. Based on the results of reflectance measurements, it can be concluded that all samples are included in the rank of lignite coal to sub-bituminous C based on ASTM D 388-05 classification. Based on TPI and GI calculations, the samples were deposited in the lower delta plain to upper delta plain depositional environments with telmatic and limno-telmatic depositional environments in wet swamp forest and fen peat swamps."

"Kandungan sulfur yang terdapat di dalam Biosolar B-30 menyebabkan kerugian karena memperpendek umur mesin kendaraan. Untuk mengatasi hal tersebut, salah satu proses untuk menurunkan kadar sulfur adalah Oxidative Desulfurization (ODS) yang memiliki keunggulan menggunakan kondisi operasi tekanan dan suhu yang rendah. Pada penelitian ini, dilakukan proses ODS menggunakan katalis karbon aktif-asam format, dan oksidator hidrogen peroksida yang memiliki kinerja terbaik menurut peneliti sebelumnya. Proses ODS dilakukan pada wadah berpengaduk pada suhu 30°C sampai 70°C dengan rasio komposisi katalis antara karbon aktif dan asam format 0,01:1 hingga 0,06:1, di oksidasi selama 40 sampai 90 menit, dan rasio molar oksidator terhadap sulfur (O/S) sebesar 6:1 sampai 80:1. Setelah proses oksidasi, dilakukan proses sentrifugasi untuk memisahkan Biosolar dengan sulfur yang telah teroksidasi. Kandungan senyawa sulfur pada biosolar sebelum dan sesudah proses ODS dianalisis dengan metode FTIR. Hasil dari penelitian yang dilakukan, katalis yang digunakan mampu mendesulfurisasi hingga 7,6%, dilakukan dengan menggunakan komposisi katalis antara Karbon Aktif-Asam Format sebesar 0,7 g-1 mL dalam 100 mL Biosolar pada suhu proses ODS sebesar 30℃, waktu oksidasi selama 60 menit, dan rasio molar H2O2/S yaitu 12.

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The sulfur content in Biosolar B-30 causes losses because it shortens the life of the vehicle engine. To overcome this, one of the processes to reduce sulfur content is Oxidative Desulfurization (ODS) which has the advantage of using low pressure and temperature operating conditions. In this study, the ODS process was carried out using an acid-activated formic carbon catalyst, and hydrogen peroxide as an oxidizing agent which had the best performance according to previous researchers. The ODS process is carried out in a stirred vessel at a temperature of 30℃ to 70°C with a catalyst composition ratio between activated carbon and formic acid 0.01:1 to 0.06:1, oxidized for 40 to 90 minutes, and a molar ratio of oxidizing agent to sulfur (O/S) of 6:1 to 80:1. After the oxidation process, a centrifugation process was carried out to separate the biodiesel from the oxidized sulfur. The content of sulfur compounds in biodiesel before and before the ODS process was analyzed by the FTIR method. The results of the research conducted, the catalyst used was able to desulfurize up to 7.6%, carried out using a catalyst composition between Activated Carbon-Formic Acid of 0.7 g-1 mL in 100 mL Biosolar at an ODS process temperature of 30℃, oxidation time for 60 minutes, and the molar ratio of H2O2/S is 12."