Degradation and filling modification of plastic waste for improvement of the slurryability of coal-plastic-water slurry. (15th July 2023)

• Record Type: Journal Article
• Authors: Zhai, Junjie; Xu, Renfu; He, Qihui; Pan, Shenglin; Wang, Xin; Zhang, Ran; Feng, Yahui; Hu, Baixing
• Is Part Of: Fuel. Volume 344(2023)
• Publication Date: 2023-07-15
• Subjects: Coal-water slurry (CWS) -- Plastic waste -- Degradation -- Filling modification -- Particle size distribution -- Rheological behavior; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2023.128137
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: Plastic wastes underwent a tough-brittle transition by degradation and modification. The coal-plastic-water slurry (CPWS) exhibited a pseudo-plastic rheological behavior. The CPWS with a high solid concentration and calorific value could be obtained. The comprehensive approach opens up a new way for the utilization of plastic wastes. Abstract: In this paper, coal-plastic-water slurry (CPWS) was prepared by blending plastic waste with coal in water. To enhance the grindability and density, the plastic waste containing polyethylene (PE) and polypropylene (PP) was treated by degradation and filling modification. The structures and properties of degraded and modified plastic waste were characterized by electron paramagnetic resonance (EPR) spectroscopy, differential scanning calorimetry (DSC), polarizing optical microscope (POM), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). Also, the mechanical properties of modified plastic waste were tested. It was suitable to use 1.0 wt% K2 S2 O8 as an assistant to degrade the plastic waste at 260° C for 3 h, and 35 wt% CaCO3 as the filling agent to modify the plastic waste. The results proved that the plastic waste underwent a tough-brittle transition by the combined treatments of degradation and filling modification. When the blending ratio range of plastic waste was from 0 to15 wt%, the CPWS with a high solid concentration greater than 66 wt% and high calorific value could be achieved by using the degraded and modified plastic waste. Additionally, CPWSs exhibited pseudo-plastic rheological behaviors. Based on the research results, a reasonable method for preparation of CPWS and a new way for utilization of plastic waste were proposed.