Process for reducing coal consumption in coal fired power plant with fluidized-bed drying

A process for reducing coal consumption in a coal fired power plant with fluidized-bed drying, comprising steps of:

• weighing raw coal from a coal powder bunker of a coal fired boiler generating set by a weighing belt;
• feeding the weighed raw coal into a fluidized-bed drying system which comprises an air lock, a fluidized-bed dryer, a dust collector, an air lock, a heat exchanger, a recirculating blower, a condensate pot and a condensate pump;
• extracting superheated steam from a fourth section or a fifth section of a steam turbine and feeding the superheated steam into the fluidized-bed dryer to dry the coal powder;
• feeding water vapor and noncondensable gas evaporated from the coal powder into a dust collector for removal of dust, enhancing the tail gas after removal of dust in pressure via a recirculating blower and then feeding the tail gas into a heat exchanger, feeding the heated tail gas as a fluidized-wind and a drying wind into the fluidized-bed dryer for recirculation;
• feeding the dried coal powder into a coal grinding mill;
• condensing the superheated steam into water, feeding the condensed water into the condensate pot, enhancing the condensed water in pressure via the condensate pump, and feeding the pressurized water into a deaerator;
• mixing the pressurized water with condensing water which has been heated by a multi-stage low pressure heater so as to be a boiler feed water with performing removal of oxygen;
• sequentially feeding the boiler feed water into a fifth high pressure heater, a sixth high pressure heater, and a seventh high pressure heater via a feed water pump, reheating the boiler feed water by heating medium respectively from extraction steams of a third section, a second section, and a first section of the steam turbine;
• and
• feeding the reheated boiler feed water into a coal economizer so as to be further heated in the boiler system, feeding the further heated boiler feed water into a steam drum for steam-liquid separation so as to be saturated steam, discharging the saturated steam from the steam drum, and feeding the saturated steam into a superheater of the boiler and then heating the saturated steam into superheated steam in the superheater of the boiler, and feeding the superheated steam into the steam turbine for generating electricity so as to perform a Rankine cycle.