Method and device for calculating combustion in waste incinerator bed

A method for calculating combustion in a bed of a waste incinerator, wherein the method is based on a model of combustion in the bed of the waste incinerator, the method comprises:

• receiving initial condition data;
• inputting the initial condition data into a governing equation of the model of combustion in the bed of the waste incinerator;
• calculating the governing equation to obtain a calculation result;
• displaying the calculation result;
• wherein
• the model of combustion in the bed of the waste incinerator comprises a moisture evaporation model, a volatile matter analysis model, a volatile matter combustion model, and a fixed carbon combustion model;
• wherein volatile matters in the volatile matter combustion model comprise CO, H2, CH4, NH3 and H2S, the volatile matter combustion model comprises a combustion reaction equation for said volatile matter and O2, and respective equations for CO and CH4 of the volatile matter reacting with water vapor;
• the governing equation for the model of combustion in the bed of the waste incinerator comprise a continuity equation, an energy equation, a momentum equation, and a component equation;
• a boundary condition of said governing equation comprise:
• a equation of heat and mass transfer from an upper boundary layer of the bed to the exterior;
• and a equations of heat and mass transfer from a lower boundary layer of the bed to the exterior, and wherein
• the mass transfer equation of the upper boundary layer of the bed to the exterior is:
• D
• g
• ⁢
• A
• ⁢
• ∂
• Y
• g
• ∂
• x
• ⁢
• ❘
• s
• =
• A
• ⁢
• ⁢
• h
• s
• ⁡
• (
• Y
• ∞
• -
• Y
• g
• ,
• s
• )
• wherein A is an area of a bed interface, with a unit of m2;
• Dg is a diffusion coefficient of a gas, with a unit of m2/s, hs is a gas-solid two-phase mass transfer coefficient with a unit of m/s;
• Y∞ is a mass traction of a gas component in the hearth;
• and Yg,s is a mass fraction of a gas component in the upper boundary layer;
• a heat transfer equation of the upper boundary laver of the bed to the exterior is:
• k
• eff
• ⁢
• A
• ⁢
• ∂
• T
• ∂
• x
• ⁢
• ❘
• s
• =
• A
• ⁢
• ⁢
• h
• T
• ⁡
• (
• T
• ∞
• -
• T
• s
• ⁢
• ⁢
• 1
• )
• +
• A
• ⁢
• ⁢
• ɛσ
• ⁡
• (
• T
• rad
• 4
• -
• T
• s
• ⁢
• ⁢
• 1
• 4
• )
• wherein keff is an effective thermal conductivity of the bed, with a unit of W/(m·s), hT is a heat transfer coefficient, with a unit of W/(m2·K);
• T∞ is temperature in the hearth, with a unit of k;
• Trad is a radiation temperature with a unit of K;
• Ts1 is a temperature of the upper boundary layer, with a unit of K, ε is a radiation coefficient, ε is 0.8;
• σ is the Boltzmann's constant.