Characterization and energy recovery of fuels from medical waste via thermal pyrolysis

This research studies the potentiality of recovering alternative fuel from the pyrolysis of syringe waste (SW) and saline bottle waste (SBW). Plastic-based medical wastes can cause severe environmental and human health damage if not properly managed. Lab-scale experiments were conducted in a batch-type fixed-bed reactor by fluctuating the temperature within the 0-600°C range at an interval of 50°C. The effect of temperature on product yield has been investigated. Various properties of pyrolytic oil extracted from SW and SBW, such as density, kinematic viscosity, pour point, boiling point, and cloud point were measured. The respective values were in the range of 726-758 kg/m³, 3.19 to 4.75 cSt, -12 to -16°C, 86-95°C, -2 to -5°C and GCV was around 42-44 MJ/kg. The GCV of pyrolytic char was around 42-43 MJ/kg. GC-MS and FT-IR tests suggested the presence of higher amounts of alcohols and organosilicons in pyrolytic oils, which evolved from SW and SBW, respectively. TGA-DTG curve indicated the thermal fracture range of SW and SBW pyrolytic oil was 50-280°C. Oil and char obtained in this study can be used as alternative fuel or chemical feedstock in different industries after some treatment. Results also showed that the properties are like low-grade liquid fuels and high-grade solid fuels. During COVID-19 and post-pandemic, a large amount of clinical waste has been used, and thus, it has become colossal waste. Pyrolysis of such waste (syringe/saline bottle) can reduce environmental contamination to a degree as well as be a substitute source of energy.