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"Merujuk pada ketentuan ILO (International Labour Organizations) yang menyatakan bahwa industri pupuk termasuk ke dalam kategori industri dengan major hazard (kebakaran, ledakan dan kebocoran bahan kimia berbahaya). Skripsi ini membahas tentang potensi terjadinya ledakan pada pipa gas hidrogen yang disebabkan oleh pelepasan gas hidrogen ke udara dan memproyeksikan area kerusakan (threat zone) akibat ledakan jika terjadi ledakan pada pipa tersebut. Penelitian ini merupakan penelitian kuantitatif dengan disain deskriptif yang menggunakan teknik event tree analysis (ETA) dan piranti lunak ALOHA (Area Locations of Hazardous Atmosphere).Hasil penelitian menunjukkan bahwa terlepasnya gas hidrogen dapat menyebabkan jet fire, flash fire, kebocoran gas beracun dan vapor cloud explosion, tergantung pada jumlah material hidrogen yang terlepas, kecukupan bercampur dengan udara dan penundaan ignisi. Proyeksi area kerusakan (threat zone) menunjukkan bahwa area merah, yaitu area yang dapat menghancurkan bangunan dan menyebabkan kematian, berada dalam radius 214 meter dengan luas area sebesar 143.930 m2. Area oranye, yaitu area yang dapat menyebabkan cedera serius, berada dalam radius 244 meter dengan luas area sebesar 187.113 m2. Area kuning memiliki radius terjauh ledakan yaitu sebesar 407 meter dengan luas area berisiko sekitar 520.611 m2.Perkiraan jumlah korban akibat ledakan ini adalah sekitar 500 orang, sebagian besar diantaranya merupakan karyawan yang bekerja di pabrik. Orang yang berisiko menjadi korban adalah mereka yang berada dalam area kuning ketika ledakan tersebut terjadi. Untuk itu, peneliti menyarankan agar PT Pupuk Kujang Cikampek meningkatkan kualitas dan kuantitas alat detektor hidrogen, membuat sistem peringatan dini, mengadakan pelatihan penanganan kebocoran bahan kimia dan meletakkan alat pemadam kebakaran lebih dekat dengan area yang kaya akan gas flammable.According to the ILO (International Labor Organizations) rule that a fertilizer company is included into the category of a major hazard industry which contains probability of fire, explosions and toxic gas released. This paper analysis about potency of explosion happenings in hydrogen gas pipes which is caused by hydrogen gas released to the air and describes threat zone because of several explosions in its pipes. This paper is a quantitative studies with descriptive design study which uses ETA (event tree analysis) technique and ALOHA (Area Locations of Hazardous Atmospheres) software.

This studies shows that hydrogen gas released to the air can cause several outcomes, like jet fire, flash fire, toxic gas released and vapor cloud explosion depending on quantity of hydrogen released, sufficiency of mixed air volume and delayed ignition. Projection of each threat zone area caused by explosion shows that red zones is 143.930 m2 in 214 m from the centre of the explosions that can destroy several buildings and potentially most caused death. Orange area is 187.113 m2 in 244 m from the centre of the explosions which can cause serious injuries. Yellow area is 520.611 m2 in 407 m out of its threat zone. The estimation about the victims of this explosion is 500 persons that most of them are the employee who works in plant. People at risk which can be a victim of it is they who is in yellow areas when the explosion was happened.

Therefore, author suggests that PT Pupuk Kujang Cikampek has to increase the quality and the quantity of hydrogen detector tools, make an early alarm system, conduct toxic material release training and provide fire extinguisher in the position that very close with the flammable gas areas."

"This research has the effort to develop catalyst for steam reforming of bio oil. The bio oil is liquidproduct that iv produced _from biomass pyrolysis. The reforming of bio oil produces hydrogen gas. The mainchallenge in reforming of organic compound especially aromatic, in bio oil as phenol, is carbon formationat the catalyst surface resulted in uncomplete reaction. The catalyst formulation resulted is expected to havehigh resistance to catalyst deactivation because of carbon formation. Beside that, it is expected too to havehigh stability and activity, compared to commercial nickel based catalyst. For those purposes, research ofsteam reforming of m-cresol in bench scale has been done. m-cresol is one of phenol compounds in bio oil,that has stable properties, difficult to react and disturb the catalyst activity. The catalyst formulation used isRu-Ni/MgO.La;O3.Al2O3 mixture. This research has succeed to develop catalyst of reforming from Ni-Rumetal combination that having the good stability and activity to reform m-cresol. The best catalystcomposition resulted is 2%Ru-15%Ni. In Ni and Ru catalyst combination, Ni catalyst is the mainly activecomponent in reforming of oxygenated aromatic compound in bio oil The Ru catalyst function is to increaseNi metal dispersion on support, by then increasing the catalyst stability."

"ABSTRACTDalam proses pengecoran aluminium, suhu leleh yang tinggi dapat meningkatkan kelarutan gas hidrogen dalam logam cair, oleh karena itu pembentukan porositas gas selama pemadatan aluminium tidak dapat dihindari dan menyebabkan kelemahan utama pada sifat mekanik. Metode yang paling umum untuk mengurangi porositas gas dalam produk casting adalah degassing. Dalam studi ini proses degassing konvensional dilakukan menggunakan tablet degasser berdasarkan NaNO3 dan NaF, dengan variasi tablet degasser menggunakan komposisi tambahan KCl atau NH4Cl. Al-Si12 dilebur pada suhu 750 oC kemudian degasser dimasukkan ke dasar tungku dan ditahan selama tiga menit kemudian logam cair dituangkan ke dalam cetakan pada suhu 690 oC. Hasil penelitian menunjukkan bahwa menggunakan tablet degasser dapat mengurangi porositas gas dan meningkatkan sifat mekanik produk casting. Dengan membandingkan variasi tablet degasser, penggunaan tablet degasser dengan penambahan NH4Cl menghasilkan produk casting dengan kandungan porositas gas terendah sekitar 0,04% dan sifat mekanik tertinggi, termasuk kekuatan tarik pamungkas hingga 203,414 MPa, nilai dampak 0,641 Nilai J / mm2 dan kekerasan sekitar 73.667 BHN. Tablet degasser dengan penambahan NH4Cl dianggap paling cocok dalam casting Al-12Si, karena senyawa tersebut menguap pada 520 oC yang sesuai dengan suhu leleh Al-12Si sehingga lebih efektif dalam membentuk gelembung untuk mengikat gas hidrogen dari aluminium cair.

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ABSTRACTIn the aluminum casting process, high melting temperatures can increase the solubility of hydrogen gas in liquid metals, therefore the formation of gas porosity during aluminum compaction is unavoidable and causes major weaknesses in mechanical properties. The most common method for reducing gas porosity in casting products is degassing. In this study the conventional degassing process was carried out using a degasser tablet based on NaNO3 and NaF, with a variation of the degasser tablet using an additional composition of KCl or NH4Cl. Al-Si12 is melted at 750 oC then the degasser is put to the bottom of the furnace and held for three minutes then the molten metal is poured into a mold at 690 oC. The results showed that using a degasser tablet can reduce gas porosity and improve the mechanical properties of the casting product. By comparing variations of degasser tablets, the use of degasser tablets with the addition of NH4Cl results in casting products with the lowest gas porosity content of around 0.04% and the highest mechanical properties, including ultimate tensile strength up to 203,414 MPa, impact value 0.641 J / mm2 value and hardness around 73,667 BHN . Degasser tablets with the addition of NH4Cl are considered to be the most suitable in casting Al-12Si, because the compound evaporates at 520 oC which corresponds to the melting temperature of Al-12Si so that it is more effective in forming bubbles to bind hydrogen gas from liquid aluminum."