Patent ID: 7287477

Claim:
A method of operating a circulating fluidized bed reactor having a furnace for combustion, a discharge port connected to the furnace for conducting combustion exhaust gas, a discharge duct connected to the discharge port, and a particle separator connected to the discharge duct for separating solid particles from the exhaust gas, wherein connected to the particle separator are a return duct connecting the particle separator to the furnace and an exhaust duct for discharging exhaust gas from the particle separator, the method comprising the steps of: arranging a bypass duct connected to the furnace and the exhaust duct, wherein the bypass duct bypasses the particle separator; conducting a partial flow of exhaust gas and solid particles entrained with the exhaust gas along the bypass duct for increasing the solid particle content in the exhaust gas after the particle separator, wherein the entrained particles are not returned back to the furnace; and controlling the exhaust gas flow in the bypass duct to adjust the quantity of solid particles bypassing the particle separator, wherein the exhaust gas flow in the bypass duct is controlled by feeding additional gas to the bypass duct.