摘要:
A package boiler having water cooled surfaces positioned relatively close to the combustion burner to improve the radiant heat transfer. Extended surfaces are added to the water cooled tube fireside surface to increase absorption rates to the limits established by water side conditions to avoid departure from nucleate boiling (DNB). The heat release rates of multiple firing rate zone burners are matched to the absorption rates of the water cooled surfaces by adjusting the size and extent of the various firing rate zones. The burner is extended or the physical shape is altered to expose a larger surface to greater areas of water cooled furnace surface. The burner is matched to cooling surface to lower combustion zone temperatures and thus thermal NO.sub.X formations. Further, recirculated flue gas, excess air, water vapor or a combination of these may be used to add mass to the fluid stream flowing through the burner. Finally, either the gas fuel or combustion air may be staged.
摘要:
An apparatus and method including a conduit with a nozzle for injecting NO.sub.x inhibiting reagent into an appropriate temperature window in the flue gas of a package, utility, or industrial type boiler to reduce emissions of NO.sub.x. A sensor mounted adjacent the nozzle to measure the flue gas temperature thereby locating the appropriate temperature window, and a controlled drive for moving the nozzle to the temperature window.
摘要:
A low NO.sub.x, integrated boiler-burner cogeneration apparatus includes a horizontally fired, factory assembled package boiler having an inlet plenum and a furnace space. A gas turbine-generator having an outlet for providing turbine exhaust gas to the furnace space is connected to the boiler. A multi-nozzle burner (MNB) array including a plurality of vertically and horizontally spaced burner nozzles is located at an entrance to the furnace space for supplying fuel for combustion into the furnace space while distributing the heat of the combustion exhaust gases across the furnace space to minimize NO.sub.x formation. One or more chill tube assemblies are located within the furnace space immediately downstream of the MNB array for rapidly reducing the temperature of the combustion exhaust gases. Laterally perforated internal duct assemblies can also be provided within the furnace space, alone or in combination with the chill tube assemblies in various arrangements to provide staging gases for completing combustion in the furnace space. A forced draft fan supplies combustion air alone or in combination with the turbine exhaust gases through the MNB array to mix with the fuel provided by the burner nozzles and produce the combustion flame.
摘要:
An apparatus for determining the relative flows of a two phase flow using differential pressure to obtain mass flow having a bend portion for concentrating the dense phase toward an outside of the bend; a perforated plate downstream of the bend for passing the portion of the light phase; a nozzle for channelling the portion of the flow having high density phase toward the center of a venturi throat which is positioned downstream of the perforated plate; and four pressure sensors strategically located for measuring pressure differences at various points in the flow meter.
摘要:
An apparatus for dispersing the relative flows of a separated two phase flow using a nozzle positioned immediately downstream from a bend in a pipe. The inlet of the nozzle is adjacent an external wall of the pipe and the outlet of the nozzle is substantially on a longitudinal axis of the pipe. The dense phase is collected and transported through the nozzle back into the center of the pipe for uniform mixing and dispersion.
摘要:
A heat recovery steam generator receives combustion gas from a gas turbine exhaust. A duct burner spans an inlet plenum of the heat recovery steam generator and staged exhaust gas is branched from the gas turbine exhaust and supplied to a chamber downstream of the plenum and the duct burner, for the purpose of reducing NO.sub.x and subsequently any CO.
摘要:
An atomizer comprises a cylindrical mixing chamber with open entry and discharge ends. An inner barrel for a slurry or fluidized dry powder is connected to the entry end for supplying the slurry or fluidized fine powder into the mixing chamber. One or more atomizing gas ports extend at an angle into the mixing chamber for supplying atomizing gas to be thoroughly mixed with the slurry or fluidized dry powder in the mixing chamber. The atomizing gas ports are spaced upstream from the discharge end by from one to five times the diameter of the mixing chamber, and downstream from the entry end. A larger diameter volume chamber communicates with the discharge end of the mixing chamber and has at least one nozzle which permits the homogenized mixture to exit therefrom. An impact surface is positioned opposite the discharge end. The at least one nozzle is positioned around the impact surface. Critical dimensional and positional features for the mixing and volume chambers, the atomizing gas ports, and the at least one nozzle produce efficient atomized sprays even at low flow velocities for the slurry or fluidized dry powder and the atomizing gas.
摘要:
A burner apparatus useful in steam producing or waste heat boilers. The apparatus includes a fuel delivery means placed between two airfoils that define an elongated venturi throat. The airfoils may be provided with a plurality of perforations to allow a secondary gas (ambient air and/or spent flue gas) to be supplied to the venturi throat for reducing NO.sub.x production.
摘要:
A low NO.sub.x, integrated boiler-burner apparatus includes a horizontally fired, factory assembled package boiler having an inlet plenum and a furnace space is provided with a multi-nozzle burner (MNB) array including a plurality of vertically and horizontally spaced burner nozzles located at an entrance to the furnace space for supplying fuel for combustion into the furnace space. The MNB array distributes the heat of the combustion exhaust gases across the furnace space for minimizing NO.sub.x formation. One or more chill tube assemblies are located within the furnace space just downstream of the MNB array for rapidly reducing the temperature of the combustion exhaust gases. Alternatively, laterally perforated internal air duct assemblies can also be provided within the furnace space alone or in combination with the chill tube assemblies in various arrangements to provide staged air for completing combustion in the furnace space. Exhaust gases from an exhaust flue of the package boiler can also be recirculated back to the inlet plenum for re-exposing the exhaust gases to the combustion process.