초록 ▼

A fluidized bed combustion system is disclosed and in particular a fluidized bed combustion system particularly well suited for the combustion of oil shale, generating steam thereby. The fluidized bed combustion system includes a furnace volume having a multi-chambered upper segment thereof, a deent

A fluidized bed combustion system is disclosed and in particular a fluidized bed combustion system particularly well suited for the combustion of oil shale, generating steam thereby. The fluidized bed combustion system includes a furnace volume having a multi-chambered upper segment thereof, a deentrainment zone, a fluidized bed having a plurality of isolatable segments thereof, a fluidized bed ash cooler having a plurality of isolatable segments thereof wherein the fluidized bed ash cooler is in fluid communication with the furnace volume, a fuel supply means in fluid communication with the furnace volume for delivering oil shale thereto for combustion therein, a backpass volume defined by a plurality of backpass wall tubes integral to a thermodynamic steam cycle and in fluid flow relation with the furnace volume and a plurality of circulatory fluid flow paths integral to a thermodynamic steam cycle and operative to conduct the flow of steam or water therethrough.

대표청구항 ▼

[ What is claimed is:] [1.] A fluidized bed combustion system having a thermodynamic steam cycle and a flue gas flow path acting in cooperative association therebetween for effecting the combustion of fuel therein including oil shale and the generation of steam thereby, said fluidized bed combustion

[ What is claimed is:] [1.] A fluidized bed combustion system having a thermodynamic steam cycle and a flue gas flow path acting in cooperative association therebetween for effecting the combustion of fuel therein including oil shale and the generation of steam thereby, said fluidized bed combustion system comprising:a. a furnace volume defined by a plurality of waterwall tubes integral to the thermodynamic steam cycle and embodying therewithina lower segment thereof for the combustion of oil shale therein generating upwardly mobile flue gases thereby andan upper segment thereof in fluid flow relation with said lower segment;b. a fluidized bed ash cooler operative as a heat exchanger in fluid communication with said furnace volume;c. fuel supply means in fluid communication with said furnace volume for delivering oil shale thereto for combustion therein;d. a deentrainment zone disposed in said lower segment of the furnace volume for deentraining particulate matter generated from said combustion and entrained within said upwardly mobile flue gases such that substantially all of said particulate matter is retained within the furnace volume, said furnace volume including a fluidized bed composed of bed solids and underbed air inlet means connected to said lower segment of the furnace volume and operative to inject upwardly flowing fluidizing air thereinto at a velocity of at least 10 feet per second, and the deentrainment zone being disposed above said fluidized bed in which some of said bed solids rise and subsequently return downwardly to said fluidized bed and said fluidized bed having a height below which said bed solids do not rise into said deentrainment zone;e. a backpass volume defined by a plurality of backpass wall tubes integral to the thermodynamic steam cycle, said backpass volume connected in fluid flow relation with the furnace volume and said furnace volume being operated such that a fraction of said particulate matter does not exit said furnace volume via said backpass volume and another fraction of said particulate matter exits said furnace volume via said backpass volume such that the percentage of the particulate matter which does not exit said furnace volume via said backpass volume is at least ninety-five percent of the total quantity of the particulate matter and the particulate matter which has exited said furnace volume via said backpass volume is subjected to electrostatically based separation before a selected one of additional separation by cyclonic based separation and no additional separation by cyclonic based separation, said backpass volume including means disposed therein for preheating air, said means having operatively connected thereto air inlet means and fluidizing air outlet means, said fluidizing air outlet means in fluid flow relation with said underbed air inlet means;f. a plurality of circulatory fluid flow paths integral to the thermodynamic steam cycle and operative to conduct the flow of steam or water therethrough, said plurality of circulatory fluid flow paths including a steam drum for separating steam from water, at least one circulatory fluid flow path integral to the thermodynamic steam cycle and operative as a water-evaporative steam loop including said waterwall tubes, means for conveying water from the steam drum thereto, means for conveying a mixture of water and steam therefrom to the steam drum, a circulatory fluid flow path integral to the thermodynamic steam cycle and operative as a water-superheated steam loop including at least one superheat heat exchange means, means for conveying steam from the steam drum thereto, a high pressure turbine, means for conveying steam from the at least one superheat heat exchange means thereto, a condenser, means for conveying steam from the high pressure turbine thereto, a fluid conveying means, means for conveying steam from the condenser thereto, at least one economizer heat exchange means, means for conveying steam from the fluid conveying means thereto, means for conveying steam from the at least one economizer heat exchange means to the steam drum, feedwater supply means, and means for conveying feedwater from the feedwater supply means to the steam drum; andg. ash discharge means for discharging ash from the fluidized bed into an area other than the backpass volume, said ash discharge means being operative to discharge the particulate matter from the furnace volume such that said height of the fluidized bed does not increase more than twenty percent during operation of the fluidized bed combustion system.