Hybrid boiler-dryer and method

A hybrid boiler-dryer for drying and burning particles of a solid fuel, comprising:

• a furnace including a firing system configured to combust the particles of the solid fuel and thereby create a flue gas;
• a flue in fluid communication with the furnace arranged to receive the flue gas therethrough;
• a sieve operative to receive the particles of the solid fuel and to separate the particles of the solid fuel into a first portion of solid fuel particles and a second portion of solid fuel particles based on a size of the particles of the solid fuel, wherein the size of the particles in the first portion of solid fuel particles are smaller than a predetermined size, and the size of the particles in the second portion of solid fuel particles are larger than a predetermined size;
• a first fuel-dryer portion comprising a first duct arranged to receive the first portion of solid fuel particles therein and to convey, via a first conveyor, the first portion of solid fuel particles therethrough to the furnace for burning by the firing system, the first duct arranged in fluid communication with the flue to receive a first portion of the flue gas therefrom to dry the first portion of solid fuel particles;
• a second fuel dryer portion disposed in the furnace including a grate disposed in a lower portion of the furnace;
• a second duct arranged in fluid communication with the flue to receive a second portion of the flue gas therefrom and to convey the second portion of flue gas therethrough to the second fuel dryer portion;
• a second conveyor to convey the second portion of solid fuel particles to the second fuel dryer portion within the furnace;
• a third conveyor to convey the second portion of solid fuel particles from the second fuel dryer portion to a mill, the mill disposed outside the furnace and configured to reduce a size of the particles of the second portion of solid fuel particles;
• and
• a fourth conveyor configured to provide the second portion of solid fuel particles from the mill to the furnace for burning by the firing system.