Abstract: A system for the comminution of coal, slurry formation and feed of the coal slurry to a fluidized bed reactor.

Abstract: A fluidized bed reactor is provided with heat exchange coils for controlling the temperature of the fluidized bed, with only vertically oriented sections of the coils exposed to the erosive conditions in the fluidized bed. The vapor-liquid circuit, of which the heat exchanger coils are a part, is arranged to operate on the principle of natural circulation. At least some of the tuyere elements discharge fluidizing gas at a level substantially above the constriction plate and the bed solids below the level of the tuyere gas discharge constitute a static layer during fluidization in which the lower angle bends of the heat exchange coils are embedded and so shielded from erosion by the fluidized solids of the bed proper. The static layer of bed solids also accommodates thermal expansion of the lower angle bend due to elevated temperatures and insulates the constriction plate from the high temperatures in the reactor.

Abstract: In order to increase or maintain the capacity of fluid bed calciners in the calcination of phosphate rock containng large amounts of organic matter ("hot rocks"), the calciner is modified to permit a pyrolysis reaction to occur in the freeboard zone of the calciner. The hydrocarbons and carbon monoxide gas produced by the pyrolysis reaction are removed from the calciner and burned in an afterburner unit. Dust and fines entrained in the exhaust from the calciner are sent to a dust oxidation chamber outside the calciner for oxidation by addition of air.

Abstract: A fluidized bed heat exchanger is provided in which air is passed through a bed of particulate material containing fuel. A steam-water natural circulation system is provided for heat exchange and the housing of the heat exchanger has a water-wall type construction. Vertical in-bed heat exchange tubes are provided and the air distributor is water-cooled. A water-cooled dust hopper is provided in the housing to collect particulates from the combustion gases and separate the combustion zone from a volume within said housing in which convection heat exchange tubes are provided to extract heat from the exiting combustion gases.

Abstract: In order to increase or maintain the capacity of fluid bed calciners in the calcination of phosphate rock containing large amounts of organic matter ("hot rocks"), the calciner is modified to permit a pyrolysis reaction to occur in the freeboard zone of the calciner. The hydrocarbons and carbon monoxide gas produced by the pyrolysis reaction are removed from the calciner and burned in an afterburner unit. Dust and fines entrained in the exhaust from the calciner are sent to a dust oxidation chamber outside the calciner for oxidation by addition of air.

Abstract: Systems for the comminution, drying and dry feed of coal for combustion in fluid bed calciners, incinerators, or other combustion systems.