Fabrication and test of a microwave pyrolyzer for simulated pathological waste

• Main Authors: Goco, Federico Noe, Rodrigo, Joanne, Ubanos, Romina Adalet
• Format: text
• Language: English
• Published: Animo Repository 2006
• Subjects: Pyrolysis > Analysis; Microwaves > Industrial applications; Ceramic materials > Effect of radiation on; Hazardous wastes
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/9829
• Institution: De La Salle University

With the passing of Republic Act 8749 in the Philippines, also known as the Clean Air Act, incineration has been banned. Prior to this, pathological wastes have been treated by means of incineration. New technologies must be developed to provide a solution for disposal of pathological wastes. Treatment of these wastes by microwave induced pyrolysis may offer the solution to the problem of disposal. The microwave oven for pyrolysis was fabricated by using a domestic Electrolux microwave. A controller was fitted to be able to maintain a set temperature, and modifications include a slot for the reactor and a Teflon seal. The reactor is made of quartz and nitrogen flowed inside the reactor to displace all air inside. Pathological wastes were simulated by the use of three types of chicken organs. These are namely the heart, liver, and intestines of the chicken. Each organ was treated separately with different percentages of microwave absorber in the form of activated carbon, and the total mass of the mixture being 30 grams. The percentages of absorber used are 0%, 5%, 10% and 15%. These are subjected to microwave heating to reach a temperature of 300°C for residence times of 5, 7, and 10 minutes. Testing for microbial activity is done by streaking solid agar medium with a wire loop which has been exposed to the pathological waste prior to pyrolysis. This is also done for the solid residue after pyrolysis. It was observed that for an increasing amount of absorber, the time it takes to reach the set point becomes shorter. For liver, the most amount of liquid was collected at 0% absorber and at 7 minutes, the most solid was collected at 5% absorber and at 7 minutes. For heart, the most amount of liquid is collected at 0% absorber and at 10 minutes, and the most amount of solid at 10% absorber and at 7 minutes. For intestines, the most amount of liquid was collected at 10% absorber and at 10 minutes, the most amount of solid at 5% absorber and at 7 minutes. In testing for the presence of microorganisms, all fresh samples showed growth on the agar plates, indicating microorganisms were present in the fresh sample. For all pyrolyze samples however, all samples showed no growth in agar plates. This indicated the absence of any microorganisms in the pyrolyzed sample.