Analisa Heat Balance Thermal Oxidizer Dengan Waste Heat Recovery Unit (Studi Kasus Central Processing Plant Gundih)

Central Processing Plant (CPP) merupakan plant yang memproses feed gas hingga menjadi natural gas siap pakai. Pengolahan feed gas di CPP menimbulkan dampak limbah berupa waste gas, terdiri dari acid gas dan vent gas, yang diolah terlebih dahulu sebelum dilepas ke lingkungan. Thermal Oxidizer (TOX) memiliki peran penting dalam mengatasi waste gas. Kinerja TOX ditentukan dari proses pembakaran yang terjadi pada burner serta suhu oksidasi waste gas pada chamber. Energi panas gas buang (flue gas) dimanfaatkan pada Waste Heat Recovery Unit (WHRU) yang berada diatas chamber, digunakan untuk memanaskan hot oil. Kondisi operasional pembakaran TOX di CPP saat ini, jumlah input sangat berbeda dengan desain awal. Suhu pembakaran juga sangat tinggi, yaitu diatas 1.600oF (1.144,261K). Sementara itu WHRU belum berjalan secara normal, suhu hot oil pada outlet WHRU masih 330-340oF (438,706-444,261K). Analisa pembakaran TOX dilakukan dengan analisa termodinamika pada jumlah bahan bakar serta jumlah udara dan excess air untuk mendapatkan pembakaran sempurna dan suhu ideal pada chamber, yaitu 1.500-1.600oF (1.088,706-1.144,261K). Bahan bakar yang digunakan sejumlah 60%-100% dari fuel gas operasional dengan kenaikan 20%, sedangkan excess air yang digunakan 10%-35% dengan kenaikan 5%. Selain itu pemanfaatan energi panas flue gas pada WHRU dilakukan analisa supaya suhu hot oil keluar WHRU mencapai 350oF (449,817K). Analisa WHRU dilakukan dengan analisa perpindahan panas compact heat exchanger, untuk mendapatkan flowrate dari hot oil dari suhu dan laju aliran massa flue gas hasil variasi pembakaran TOX tersebut. Dari penelitian Tugas Akhir ini, suhu TOX hasil pembakaran operasional yang sesuai dengan desain awal yaitu pada 60% fuel gas dengan excess air (EA) antara 30% hingga 35%. Pada 60% fuel gas dengan EA antara 30% hingga 35% didapatkan suhu antara 1.095K hingga 1.138K. Pada hasil analisa WHRU, untuk mencapai suhu hot oil sebesar 350oF (449,817K) pada variasi TOX tersebut diperlukan laju aliran massa hot oil sebesar 1.257,720 kg/jam dan 1.481,420 kg/jam. ================================================================================================================== Central Processing Plant (CPP) is a plant that processes the feed gas into ready to use natural gas. This process cause waste which need to be treated before it released into the environment. Thermal Oxidizer has an important role in solve that problem. TOX performance determined from combustion process that occurs at the burner as well as temperature oxidation of waste gas in the chamber. The heat of flue gas is used in the Waste Heat Recovery Unit (WHRU), which located above the chamber, to heat hot oil. In the current operating conditions of combustion in TOX, the number of input supply has a significant difference from the initial design. The combustion temperature has also exceed from the design, that is above 1,600oF (1,144.261K). Meanwhile the WHRU is not running normally. The temperature of hot oil on the outlet WHRU is still 330-340oF (437.706-444.261K). TOX combustion analysis conducted by the thermodynamic analysis on the amount of fuel, air and excess air to get the perfect and ideal temperature combustion chambers, that is 1.500-1.600oF (1,088.706-1,144.261K). The amount of fuel use 60% -100% of the operational fuel gas with a rise of 20%, while excess air use 10% -35% with a rise of 5%. In addition, analysis of WHRU need to be conducted to utilize of heat in the flue gas so that the temperature of hot oil on the outlet WHRU reached 350oF (449.817K). WHRU analysis conducted by compact heat exchangers heat transfer analysis, to obtain the hot oil flow rate from temperature and mass flow rate of flue gases produce from combustion variation of the TOX. From this final project research, TOX combustion temperature that same with the inital design is at 60% of fuel gas with excess air (EA) between 30% to 35%. In 60% of fuel gas with EA between 30% to 35% obtained a temperature between 1,095K up to 1,138K. In the results of WHRU analysis, to reach the temperature of hot oil at 350oF (449.817K) on the variation of the TOX required mass flow rate of hot oil amounted to 1,257.720 kg/hour and 1,481.420 kg/hour