High-density polyethylene(HDPE)pipes have gradually become the first choice for gas networks because of their excellent characteristics.As the use of pipes increases,there will unavoidably be a significant amount of w...High-density polyethylene(HDPE)pipes have gradually become the first choice for gas networks because of their excellent characteristics.As the use of pipes increases,there will unavoidably be a significant amount of waste generated when the pipes cease their operation life,which,if improperly handled,might result in major environmental contamination issues.In this study,the thermal degradation of polyethylene materials is simulated for different pressures(10,50,100,and 150 MPa)and temperatures(2300,2500,2700,and 2900 K)in the framework of Reactive Force Field(ReaxFF)molecular dynamics simulation.The main gas products,density,energy,and the mean square displacement with temperature and pressure are also calculated.The findings indicate that raising the temperature leads to an increase in the production of gas products,while changing the pressure has an impact on the direction in which the products are generated;the faster the temperature drops,the less dense the air;both temperature and pressure increase impact the system’s energy conversion or distribution mechanism,changing the system’s potential energy as well as its total energy;the rate at which molecules diffuse increases with temperature,and decreases with pressure.The results of this investigation provide a theoretical basis for the development of the pyrolytic treatment of polyethylene waste materials.展开更多
基金supported by the sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2022D01C389)the Xinjiang University Doctoral Start-Up Foundation(No.620321029)the Science and Technology Planning Project of State Administration for Market Regulation(No.2022MK201).
文摘High-density polyethylene(HDPE)pipes have gradually become the first choice for gas networks because of their excellent characteristics.As the use of pipes increases,there will unavoidably be a significant amount of waste generated when the pipes cease their operation life,which,if improperly handled,might result in major environmental contamination issues.In this study,the thermal degradation of polyethylene materials is simulated for different pressures(10,50,100,and 150 MPa)and temperatures(2300,2500,2700,and 2900 K)in the framework of Reactive Force Field(ReaxFF)molecular dynamics simulation.The main gas products,density,energy,and the mean square displacement with temperature and pressure are also calculated.The findings indicate that raising the temperature leads to an increase in the production of gas products,while changing the pressure has an impact on the direction in which the products are generated;the faster the temperature drops,the less dense the air;both temperature and pressure increase impact the system’s energy conversion or distribution mechanism,changing the system’s potential energy as well as its total energy;the rate at which molecules diffuse increases with temperature,and decreases with pressure.The results of this investigation provide a theoretical basis for the development of the pyrolytic treatment of polyethylene waste materials.
