1. Entrained-flow Gasifier Model Development Larry Baxter, Bing Liu, Humberto Garcia

2. Distinguishing Characteristcs Focus on refractory durability Chemical dissolution Fracturing Spalling Advanced inorganic coal chemistry Initial inorganic speciation Particle and gas dynamics Deposit/slag formation Numerically efficient New, rapid gas-phase convergence 1-D reactor profile 2-D slag/refractory/deposit profile

3. Capabilities and Status Estimates transient gas and particle composition, temperature, velocity, and position as a function of axial position. Estimates transient slag and refractory thickness, composition, temperature, and phase as functions of both axial and radial position. Suitable for monitoring and supervisory control, either in full or in correlated form. Steady-state version in debug mode. Validated and verified model complete by end of CY 2007.

4. Overall Concept

5. Reactor Model

6. Reactor Model Details

7. Wall Model Details

8. Mechanical Model Details

9. Mechanical Model Interface Deposit Phase Gas and Particle Phases Refractory / Metal Phase Axial temperature profiles, mass flux, particle composition Depth, phase, composition, temperature, and flow rate (radial and axial) Deposit- refractory interface composition, temperature, and properties Thermal & mechanical stresses, fracturing/spalli ng, psd of spalled particles, erosion, corrosion Gas and particle composition, velocity, and temperature (axial) Chemical dissolution Gas-deposit interface conditions (T, ε, phase, μ) Slag absorption, spall psd, T, Δx

10. Database-driven Information

11. Sequence Diagrams

12. Deposits Dissimilar to Fuel

13. Example Gasifier dimensions (length×diameter×thickness) Steel shell: 3.0×1.06×0.03 (Unit: m) Refractory: 3.0×1.0×0.3 (Unit: m) Coal: Illinois #6 Operating Temperature: ~1800 C Operating Pressure: ~40 atm

14. Gas Composition Profile dry coal, high equiv. ratio, O 2 feed

15. Corrosion Rate Dependencies Corrosion flux is calculated using the falling film diffusion model. The corrosion rate increasing with temperature results from two effects: (1) Solute diffusion coefficient increases exponentially with increasing temperature; (2) the saturated solute concentration increases with increasing temperature.

16. Δt = ∞ Δt = 100 hr Δt = 50 hr The computation is conducted at the 0.3 m from the top of the gasifier. 1800 C syngas temperature is used. 1/Δt is the assumed spalling frequency. The curves become flat at long time resulting from the decreasing hot-face temperature of the refractory with time. Refractory Thickness Dynamics