- Document Number:
20110214427
- Appl. No:
13/039707
- Application Filed:
March 03, 2011
- Abstract:
The present invention relates to a process for reducing coal consumption in coal fired power plant with steam-piping drying, namely a steam-piping drying system is provided between a coal grinding mill and a coal powder bunker as well as a weighing belt of the prior coal fired boiler generating set, and superheated steam which have done partial work is extracted from an steam turbine and used as a drying medium, moisture contained in the coal powder is evaporated with sensible heat and latent heat of the superheated steam, water resulted from the condensation of the superheated steam is fed into a deaerator of the steam turbine via a condensate pump for recirculation. The present invention has advantages of reducing coal consumption and saving coal, recovering residual heat, reducing emission of carbon dioxide and adopting to the national industrial policy on energy saving and emission reduction.
- Inventors:
Zhao, Xu (Lanzhou, CN); Zhang, Maikui (Lanzhou, CN); Dou, Yan (Lanzhou, CN); Jiang, Yongzhong (Lanzhou, CN); Shi, Jinwen (Lanzhou, CN)
- Claim:
1. A process for reducing coal consumption in a coal fired power plant with steam-piping drying, comprising the 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 an steam-piping drying system; extracting superheated steam from a fourth section or a fifth section of a steam turbine and feeding the superheated steam into the steam-piping drying system to dry the coal powder; feeding steam and noncondensable gas evaporated from the coal powder into a dust collector for removal of dust and discharging tail gas after removal of dust completely via a tail gas fan; feeding the dried coal powder into a coal grinding mill; condensing the superheated steam for drying into water, and feeding the condensed water into a condensate pot, enhancing the condensed water in pressure via a condensate pump, and then feeding the pressurized water into a deaerator; mixing the pressurized water with condensed 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 together; 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 in turn and reheating the boiler feed water by heating medium from extraction steam 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, 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.
- Claim:
2. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 1, wherein the steam-piping drying system comprises a steam-piping dryer, the dust collector, the tail gas fan, the condensate pot, and the condensate pump.
- Claim:
3. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 1, wherein the drying medium used in the steam-piping drying system is extraction steam from the steam turbine, the extraction steam is from the first section, the second section, the third section, the fourth section, the fifth section, the sixth section or the seventh section of the steam turbine, and the extraction steam has a pressure of 0.6-0.8 MPa.
- Claim:
4. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 1, wherein the steam-piping dryer in the steam-piping drying system may be a heat conduction dryer such as a steam-pipe rotary dryer, a pipe bundle dryer or a pipe dryer.
- Claim:
5. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 1, wherein the dust collector in the steam-piping drying system is a dry dust collector or a wet dust collector.
- Claim:
6. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 5, wherein the dry dust collector is a cyclone separator, a bag dust collector, or an electrostatic precipitator; the wet dust collector is a Venturi wet dust collector, a swashing wet dust collector, or a wet washing tower.
- Claim:
7. The process for reducing coal consumption in a coal fired power plant with steam-piping drying according to claim 1, wherein the boiler in the steam-piping drying system is a coal powder boiler system requiring a coal pulverizing system or a circulating fluidized bed boiler system without pulverizing.
- Current U.S. Class:
60/653
- Current International Class:
01
- Accession Number:
edspap.20110214427
Processing Request
No Comments.