Judul: Penggunaan Pelet Kombinasi Kapur Tohor (CaO) dan Serbuk Gergaji untuk Menangkap Karbon Dioksida (CO2) pada Biogas
Abstrak: Potensi biogas sangat besar sebagai sumber energi terbarukan karena kandungan metana (CH4) yang tinggi dan nilai kalornya yang cukup tinggi yaitu berkisar antara 4.500–6.300 kkal/m3. Metana yang hanya memiliki satu karbon dalam setiap rantainya, dapat membuat pembakarannya lebih ramah lingkungan dibandingkan bahan bakar berantai karbon panjang. Kemurnian biogas yang dihasilkan dari biodigester belum optimal, kandungan CH4 sekitar 50-60% serta CO2 sekitar 40-60%. Kandungan CO2 pada biogas masih cukup besar, hal ini menyebabkan efisiensi panas yang dihasilkan masih rendah sehingga kualitas nyala api biogas masih belum optimal. Optimalisasi penggunaan biogas dilakukan dengan cara pemurnian, salah satu caranya adalah dengan menggunakan pelet dari kombinasi CaO dan serbuk gergaji kayu.
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Judul: Pemanfaatan Bagase Tebu dan Limbah Nanas Sebagai Bahan Baku Penghasil Biogas
Abstrak: Perkembangan kebutuhan energi dunia yang dinamis di tengah semakin terbatasnya cadangan energi fosil serta kepedulian terhadap kelestarian lingkungan hidup, menyebabkan perhatian terhadap energi terbarukan semakin meningkat, terutama pada sumber energi terbarukan di sektor pertanian seperti komoditi tanaman pangan, hortikultura, perkebunan dan peternakan. Limbah biomassa padat dari pertanian dan perkebunan merupakan bahan baku yang potensial untuk diolah menjadi salah satu bentuk bioenergi yakni biogas melalui pemanfaatan teknologi anaerobik. Bagase merupakan limbah padat dari pabrik gula dan limbah nanas adalah sisa dari pabrik pengolahan buah. Bagase tebu masih mengandung senyawa organik majemuk, dan jika tidak dilakukan pengolahan, akan menimbulkan bau yang kurang sedap dan akan mencemari lingkungan. Sedangkan limbah nanas mengandung karbohidrat (6,41%), mineral dan protein mentah (0,6%) yang berpotensi sebagai substrat fermentasi. Biogas merupakan bahan bakar yang mengandung nilai kalori yang cukup tinggi, yaitu 4500 – 6300 kkal/ m3 .Volume biogas 1 m3 setara dengan 0,8 liter bensin, 0,52 liter solar, 0,62 liter minyak tanah, 0,46 kg elpiji dan 3,5 kg kayu bakar. Energi yang terkandung dalam biogas tergantung dari konsentrasi metana (CH4). Semakin tinggi kandungan metana maka semakin besar kandungan energi (nilai kalor) pada biogas.
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Judul: Exchange Market Pressure and Central Bank Intervention for Three ASEAN Countries
Abstrak: Two of the exchange rate systems which are adopted by many countries are the floating and the fixed exchange rate system. Both the exchange rate systems have different characteristics. Countries that implement fixed exchange rates system tend to set their domestic currency exchange rate at a certain point. On the contrary, countries which implement floating exchange rate system tend to let their domestic currency exchange rate to move flexibly and thus their value will always change according to the demand and supply of the currency in the foreign exchange market. Countries which implement floating exchange rate system are facing the risk of fluctuation in the exchange rate of their domestic currency against foreign currencies. The currency exchange rate fluctuation may be caused by economic problems such as a financial crisis. A country can also be potentially affected by other countries’ earlier financial crisis. This effect could potentially happen if these countries are in the same region, such as ASEAN. The 1997 ASEAN economic crisis was an example of a country’s financial crisis could affect other countries. At that time, some countries such as Indonesia, Malaysia and Thailand had to change their currency exchange rate system from the fixed exchange rate system to the floating exchange rate system due to the high costs which has to be incurred if they were to enforce the fixed exchange rate system. During 2002 until 2012, the domestic exchange rate of Indonesia, Malaysia and Thailand against the U.S. dollar had tended to fluctuate. If the domestic currency exchange rate fluctuated excessively then the central bank would intervene to stabilize the exchange rate in the foreign exchange market. The pressure on domestic currency exchange rate pressures has forced the central bank to intervene. The amount of those pressures can be analyzed by calculating the Exchange Market Pressure (EMP) index. Apart from that, the time when interventions are done by the central bank can be known based on EMP by calculating the Exchange Market Intervention (EMI) index. The purposes of this study were to determine the level of international pressure on the currency exchange market and monetary authorities intervene in three ASEAN countries, as well as to determine the effect of the monetary authorities intervene on the exchange rate of the domestic currency against the U.S. dollar in those three ASEAN countries. Based on the EMP index calculation results which are obtained during 2002 to 2012 period, the exchange rate of Indonesia, Malaysia and Thailand’s domestic currency had always fluctuated and the results of the EMP index indicated that each country were under diverse level of currency exchange rate appreciation and depreciation pressures. Thailand was the country with the highest currency exchange rate pressure compared to Indonesia and Malaysia. The results on the intervention index calculation showed that Indonesia, Malaysia and Thailand have intervention index between zero and one and more than one. We can also see from the intervention index that Indonesia and Thailand implement the controlled floating currency exchange rate instead of the freely floating one. Based on the calculation of the currency exchange rate by comparing
Keyword: exchange rate, exchange market pressure, intervention