title: Numerical simulation of gas concentration and dioxin formation for MSW combustion in a fixed bed.
abstract: A numerical model was employed to simulate the combustion process in a fixed porous bed of municipal solid waste (MSW). Mass, momentum, energy and species conservation equations of the waste bed were set up to describe the incineration process. The rate of moisture evaporation, volatile matter devolatilization, char combustion, NOx production, and reduction and dioxin formation were calculated and established according to the local thermal conditions and waste property characteristics. Changes in the bed volume during incineration were calculated according to the reaction rate of the process. The simulation results were compared with experimental data, which shows that the incineration process of waste in the fixed bed was reasonably simulated. The simulation results of weight loss and solid temperature in the bed agree with the experimental data, which shows that the waste combustion rate is nearly constant in the middle of the incineration process, and that moisture evaporation takes up most of the time for the overall incineration experiment. The emission of gas species from the bed surface is also agreeably simulated, with O2, CO2, and CO concentrations in flue gas agreeing with the experimental data. The simulation results benefit the understanding of the combustion process in the waste bed as well as the design of incinerator grates.
authors.affiliation: School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001, PR China. Electronic address: Sunsr@hit.edu.cn.
authors.forename: Rui
authors.initials: R
authors.lastname: Sun
authors.affiliation: Department of Mechanical Engineering, Suez Canal University, Ismailia, Egypt. Electronic address: temoil@aucegypt.edu.
authors.forename: Tamer M
authors.initials: TM
authors.lastname: Ismail
authors.affiliation: School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001, PR China.
authors.forename: Xiaohan
authors.initials: X
authors.lastname: Ren
authors.affiliation: Department of Basic Science, Cairo University, Giza, Egypt.
authors.forename: M
authors.initials: M
authors.lastname: Abd El-Salam
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D002248:Carbon Monoxide / Q000737:chemistry; D004147:Dioxins / Q000737:chemistry*; D006801:Humans; D017745:Incineration / Q000379:methods*; D008962:Models, Theoretical; D010100:Oxygen / Q000737:chemistry; D012037:Refuse Disposal; D062611:Solid Waste
chemical_list: D004147:Dioxins; D062611:Solid Waste; D002245:Carbon Dioxide; D002248:Carbon Monoxide; D010100:Oxygen
keywords: Dioxin formation; Fixed bed; Municipal solid waste; Numerical simulation models; Waste incineration