Energy-consumption diagnosis is an important technology for energy conservation of in-service power plants. Compared with regular pulverized coal boiler

the circulating fluidized bed(CFB) boiler has obvious different in combustion mode

so it requires some customized analysis and computation methods for energyconsumption diagnosis. The key point is to propose the energy efficiency index

which is the precedent of improvement suggestion. The state specification theory notes that the flow regime

called the state

depends on fluidizing velocity

circulating rate and particle size distribution. State reconstruction is to decrease bed pressure in furnace by increasing the ratio of particles with appropriate size in bed inventory. Energy-consumption diagnosis of CFB boiler means to determine the least cost of maintaining the total material balance in CFB boiler and suitable state in certain part. This technology should accord with the characteristics of CFB combustion as well. In detail

the influences of fuel

limestone

cyclone

bed pressure drop in upper furnace

high pressure fluidizing air and air distributor were discussed. Their energy efficiency indices and analysis methods were proposed.