Superheated Steam Drying with Heat Recovery used to Pre-dry Green Wood Chips
| Pre-drying | Turbo Drying | ||
| Green Wood | 50,000 | 40,000 | lbs per hour |
| Moisture Content | 50% | 38% | MC |
| Water in Wood | 25,000 | 15,000 | lbs/hr |
| Bone Dry Wood | 25,000 | 25,000 | lbs/hr |
| Moisture Content after Drying | 38% | 8% | MC |
| Wood after Drying | 40,000 | 27,174 | lbs/hr |
| Water Removed in Dryer | 10,000 | 12,826 | lbs/hr |
| Heat Load for Drying | 1,447.00 | 1,401.85 | Btu/lb water |
| Total Heat Load for Drying | 14.5 | 18.0 | MMBtu/hr |
| Dryer Inlet Steam Temp | 428 | F. | |
| Dryer Inlet Steam Enthalpy | 1,253.18 | Btu/lbm | |
| Density of Inlet Steam | 0.0279 | ft3/lbm | |
| Dryer Outlet Steam Temp | 302 | F. | |
| Outlet Steam Enthalpy | 1,193.56 | Btu/lbm | |
| Density of Outlet Steam | 0.0327 | ft3/lbm | |
| Change in Enthalpy | 59.62 | Btu/lbm | |
| Steam Recirculated | 301,563 | lbm/hr | |
| Steam Vented at 302 F. | 12,826 | lbs/hr | |
| Vented Steam Enthalpy | 1,193.56 | Btu/lbm | |
| 15.31 | MMBtu/hr | ||
| Calculation of Heat Input to Superheated Steam Dryer | |||
| Heat 1 lb of moisture from 68 F. to 212 F. | 144 | 144 | Btu/lbm water |
| Heat 1 lb of dry wood from 68 F to 212 F Cp = 0.3 | 43.2 | 43.2 | Btu/lbm dry wood |
| Evaporate 1 lb water at 212 F. | 970.4 | 970.4 | Btu/lbm water |
| Superheat 1 lb of vented steam from 212 to 302 F. | 43.08 | 43.08 | Btu/lbm steam |
| Moisture Content of Feed | 50% | 38% | |
| Heat Water to 212 F. | 72.00 | 27.00 | reduce 50% via Preheat |
| Heat Wood to 212 F. | 21.60 | 13.50 | reduce 50% via Preheat |
| Evaporate Water at 212 F. | 485.20 | 363.90 | |
| Superheat Steam to 312 F. | - | 16.16 | |
| 578.80 | 420.56 | Btu/lb of wet Wood | |
| 1157.60 | 1121.48 | Btu/lbm water | |
| Incl. 20% for Structural Losses | 1447.00 | 1401.85 | Btu/lbm water |
