BOILER WITH CIRCULATING LAYER Russian patent published in 1997 - IPC

FIELD: heat-power engineering. SUBSTANCE: boiler has furnace 1 and convective shaft 2 connected by means of horizontal gas duct 3. Fitted at gas duct inlet is ash-entrapping tube bundle 4 which performs function of inner separator for return of large particles to furnace 1. Members of external separation system 5 are mounted at gas duct outlet. These members are made in the form of curvilinear guide passages 6 with dividers 7 used for crushing and turning the gas flow and introducing it into external separation system 5 which is made in the form of two and more dry inertial apparatus, type cyclone, battery cyclones, vortex traps, etc. Outlet passages of separation system are connected with collecting bin 17 which is brought in communication with furnace 1 by means of return line at adjustable flow rate through nonmechanical valves 20. EFFECT: higher efficiency. 2 dwg