Experimental study on preparation of fuel by low-temperature pyrolysis of plastic waste combined with desiccated sludge after preforming

¹ MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Beijing University of Technology, Beijing, 100124, China
² Beijing Key Laboratory of Heat Transfer and Energy Conversion, Beijing University of Technology, Beijing, 100124, China

Abstract

Take plastic waste and dried sludge as raw materials, use pressure testing machine and high temperature hot pressing mold to test under different parameters. The effect of raw material ratio, low-temperature pyrolysis temperature, molding pressure and heating time on the physical properties of the molded fuel after low-temperature pyrolysis, such as relaxation density, fall strength, compressive strength and water permeability, are studied. Single factor tests show that the general range of mixed molding parameters is: mixture ratio (dry sludge: composite plastics) 85:15~75:25, temperature 150~250°C, heating time 20~40min, compaction pressure 2~6MPa. Orthogonal test is designed on the basis of single factor test. The results show that the most important factor affecting the relaxation density of molding fuel is molding pressure, the most important factor affecting compressive strength is the ratio of raw materials, and the most important factor affecting water permeability is heating time. The fall strength is less affected by various factors. It is due to the stickiness of the molded plastic after softening, which strengthens the “cohesion” between the raw materials, and will not be explored in the orthogonal experiment. The optimal combination of relaxation density molding parameters is the ratio (dry sludge: composite plastics) 80:20, temperature 250°C, heating time 30min, compaction pressure 6MPa; the optimal combination of compressive strength molding parameters is 75:25, 250°C, 30min, 6MPa; the optimal combination of anti-moisture absorption performance molding parameters is 85:15, 150°C, 30min, 2MPa.