Fuel gases from pyrolysis of waste Polyethylene sachets

Evaluation of fuel gases produced from pyrolysis of waste polyethylene was carried out. Waste polyethylene (pure water sachets) was pyrolysed at low and high temperatures. Pyrolysis of the waste for 300secs at temperatures of 25°C -140°C produced 2.53% ethane, 21.67% propane and 75.82 % propylene. The volume of the gaseous products at this low temperature is far less than the initial volume of the waste resulting into over 80% reduction in the volume of waste generated by discarding the polyethylene waste. Fresh samples of the waste were pyrolysed at higher temperature range from 50°C – 250°C and cooled in a condenser. The non-condensable gas produced were collected and analyzed with Shimadzu gas chromatography. The analysis shows that C₁ – C₆, and other alkenes and isoparaffins (18 ethylene monomers) were produced. The gaseous products being 75.82% propylene at low temperatures and 48.6% (normal and Iso) butane at higher temperatures. The flame test carried out shows that the gaseous products burns with a blue flame at lower temperature range. Above 300°C the flame becomes more luminous and production of fuel gases stops at 550°C. Production of fuel oil from waste polyethylene led to production of large volume of gaseous products, some of which are non-condensable at room temperature. The gaseous products can serve as feedstock and as fuel gas.