The effect of temperature on the Emission Factor of air emissions from pyrolysis of used tyres

• The designed and constructed pyrolysis chamber and condenser units worked effectively as expected for tyre pyrolysis and condensation process. • Emission concentrations from the study were higher than the standard limit set by the Federal Ministry of Environment [ 4 ] which signifies great danger to the ambient environment and people's healthy living. • Higher amounts of pyrolysis oil and gases were observed at a temperature range of 250 °C and 300 °C while above 400 °C, the yield of oil decreased and thus leads to an increase in gaseous emission. Used tyres pyrolysis is an efficient solid waste management strategy for used tyres and a growing method of fuel oil production. However, the impact of air emissions associated at different temperature on ambient air quality has not been determined. To solve this problem, a pyrolysis fixed bed reactor and a condensing unit for separating liquid from produced gas were designed and constructed. 0.20 kg of used tyres were pyrolysed in the reactor and air emissions from the reactor chamber was characterized for air pollutants using the E-instrument E8500. Using a combination of measured mass of pollutants, mass of tyre pyrolzed and time taken during pyrolysis, Emission Factors of the air pollutants were established from the study at 200 °C, 300 °C and 400 °C. The concentration measured between 200 °C - 400 °C were in the range of 15 -7497 mg/m 3 , 0 – 4680 mg/m 3 , 38.25 – 103, 277.76 mg/m 3 and 2 – 293 mg/m 3 for CO, NO x , HC and H 2 S respectively. The developed emission factors were in the range of 16.52 – 8370.04 g kg -1 , 0 – 4470.26 g kg -1 , 42.126 – 104,055.9 g kg -1 and 2.20 – 322.69 g kg -1 . The designed and constructed pyrolysis reactor and condenser unit were effective for used tyre pyrolysis while the measured air pollutants concentration were higher for all pollutants except H 2 S using the Federal Ministry of Environment (FEPA, 1991) standard. Hence, it is necessary to carry out further studies on air pollution control from waste tyre pyrolysis at lower temperature.