Pyrolysis of Waste Plastics: Effect of Heating Rate on Product Yields and Oil Properties

Abstract

Selecting typical waste plastics, polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC), and their mixture PE/PP/PVC as experimental samples, pyrolysis experiments were conducted on tubular furnace reactor at heating rates of 3.7 ℃•min -1 , 9.0 ℃•min -1 , 20.6 ℃•min -1 and 33.3 ℃•min -1 respectively to investigate effect of heating rate on yields of pyrolysis product (cracking oil, cracking gas and residue) and oil properties. The results showed that cracking oil yield was increased, but both the yields of cracking gas and residue were decreased, together with increasing heating rate. The decrease of residue yield was negligible. With the rise of heating rate, calorific value of cracking oil produced from PE and mixture of plastic was decreased and calorific value of oil produced from PP was increased, while that of PVC was decreased at first and increased later. Variations in components distribution of cracking oil generated from different kinds of plastics were different from each other. The results are probably supposed to provide reference for the optimization of pyrolysis process parameters of waste plastics.

Influence of Residence Time to the Properties of Liquid Product From Plastic Waste Pyrolysis

“…The trend of oil and gas production has increased and the solid product has decreased from the pyrolysis process is in agreement with the research conducted by Pei et al (2013) [13]. They reported that pyrolysis can be seen as a process for removing volatile materials from plastic waste.…”

“…The highest heating value was produced by the pyrolysis process with 90 min residence time, which was 20.047 BTU/lb. This condition is in accordance with Pei (2013), where the heating value of oil formed from PE plastic will decrease with a decrease in the residence time, which was due to a decrease in the smaller number of hydrocarbon fractions that had high heating value in pyrolysis oil; therefore, the total calorific value of oil was smaller.…”

Design of a Simple Pyrolysis Reactor for Plastic Waste Conversion into Liquid Fuel using Biomass as Heating Source

“…The quite similar range also applies for HDPE, at 378-539 °C (Anuar Sharuddin et al, 2016). Besides temperature, the heating rate also brings a significant effect, either for conversion rate or product composition and calorific value (Tao et al, 2013).…”

Proses Pirolisis Sampah Plastik dalam Rotary Drum Reactor dengan Variasi Laju Kenaikan Suhu

“…Hasil penelitian menunjukkan bahwa rendemen minyak akan meningkat seiring dengan kenaikan laju pemanasan, akan tetapi rendemen gas dan residu padatan akan menurun. Variasi dari distribusi senyawa di dalam minyak yang dihasilkan dari bermacam-macam plastik juga berbeda antara satu sama lain [18].…”

“…Lebih spesifik lagi, jika suhu proses sangat tinggi, maka bahan organik dengan titik didih dan berat molekul yang besar, yang selama ini tertinggal sebagai bagian dari residu padatan, akan terlepas dalam bentuk gas yang menguap. Pada akhirnya, gas-gas yang menguap tersebut akan terkondensasi menjadi minyak [18].…”