Judul: Desain dan Uji Kinerja Alat Pembakar Sampah (Incinerator) Tipe Batch Untuk Perkotaan Dilengkapi dengan Pemanas Air
Abstrak: Municipal solid waste (MSW) management is very important in order to keep the city clean, beautiful, and health. The waste could be utilized by various process that suitable each kind of waste. Organic waste can be utilized by composting process or biogas generation. While an-organic waste can be recycled. Incinerator was needed for toxic and medical waste utilization, due to its capability to burnt off the toxic materials. Small incinerator seems an important solution for urban household waste management due to the shortage area for composting or other waste utilization. Beside that, heat energy which produced by combustion process in the incinerator could be use for several purposes to fulfill household demand such as drying process or water heater process. The aim of this study is to design an incinerator which can be implemented in the urban household. Those incinerator combined with water heating system as utilization of heat energy produced by the combustion process and smoke cyclone which can be used for drying or carbonization process Result of the performance of the incinerator shows that the incinerator working well. The capacity of the incinerator is 0.294 m3. The weight of the waste that filled the incinerator is 10.5 to 18.3 kg. The maximum burn temperature is 413 to 478 oC. The incineration rates of the incinerator around 2.81 to 6.82 kg/hour. Quality of smoke is good, showed by the colour of the smoke (near white). Heat energy produced by the system has been used for water heating and coconut shell carbonization process. Using water flow rate 3 l/minutes, the temperature of the water can be raised 14-18 oC per batch process. While carbonization process only produce 10% charcoal from 5 kg coconut shell which has been feed in the smoke cyclone room Modification of the gas hole can increasing the temperature of incineration and modification of the length and relocation of pipe can increasing the water heater performance.
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Judul: Modification design of incinerator multifunction continue type
Abstrak: Incinerator is an equipment to incinerate trashes with high temperature control to ensure that the combustion process was done completely. The previous design of batch type incinerator which has been designed by Pradipta (2011) has some disadvantages, such as heat transfer system, loading and unloading system, air supply system and utilization of heat energy. So, those design should be modified to improve its performance. The performance parameters of incinerator are temperature of combustion, the rate of combustion, quality of exhaust gases, safety factor, and utilization of heat energy. Modified incinerator has eight sections (combustion chamber, chimney, air inlet, hopper, boundary plate, ash chamber, charcoal chamber, and water heater pipe). The performance test shows that the highest combustion temperature is 689.6 ⁰C, with combustion rate 5.78 kg / hour. The incinerator is safe for operator and the exhaust gasses has good quality. Utilization of thermal energy could increasing water temperature up to 32 ⁰C. Air inlet position was not in the proper place, so combustion temperature could not reach as high as expected. Therefore it need improvement.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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