Abstract: A gas and steam-turbine plant includes a waste-heat steam generator downstream of a gas turbine on the exhaust-gas side. The waste-heat steam generator has a high-pressure preheater connected into a water/steam circuit of a steam turbine having a low-pressure part. In order to achieve as high a plant efficiency as possible, a heat exchanger which is disposed outside the waste-heat steam generator has a primary-side inlet connected to an outlet of the high-pressure preheater, a primary-side outlet connected to an inlet of the high-pressure preheater and a secondary side connected into an overflow conduit opening into the low-pressure part of the steam turbine. A method for operating such a plant includes superheating low-pressure steam flowing into the steam turbine by indirect heat exchange with a part stream of preheated feed water extracted from the high-pressure preheater.

Abstract: A heat recovery steam generator system which includes a plurality of side waterwalls defining an enclosure and a waterwall divider extending within the enclosure to define first and second chambers within the enclosure. The first chamber has an inlet and an outlet; and the second chamber has first and second inlets and an outlet, the first inlet of the second chamber is in fluid communication with the outlet of the first chamber, and a plurality of boiler bank tubes extend through the second chamber. Some forms of the invention have ducting for connecting the exhaust of an associated gas turbine partially to the inlet of the first chamber and partially to the second inlet of the second chamber. A plurality of burners may be disposed at the inlet of the first chamber and the system may also include a forced draft blower for blowing ambient air and ducting coupling the forced draft blower to the inlet of the first chamber.

Abstract: A process and equipment for generating useful power comprising a special split stream heat recovery boiler 108 in combination with a gas turbine 20 and a steam turbine 80 to form a combined cycle. A steam-injected gas turbine 20 and alternately a condensing steam turbine 116 may be utilized. A topping high temperature and high pressure topping steam turbine 80 optionally may be included. Chemical heat recuperation via natural gas reformation may be incorporated within the boiler 108 to increase cycle efficiency further and to lower NOx formation without excess CO. The heat recovery boiler 206 yields increased efficiency and power output heretofore unexpected for the combined cycle compared to conventional combined cycle equipment.

Abstract: Combined cycle power plants are disclosed that utilize a stream of compressed flue gas and fuel that has been passed through a reformer (a thermochemical recuperator) to increase its thermal and chemical value and, along with the output of an air compressor, is fed into the gas turbine combustor. In preferred embodiments the thermochemical recuperation and flue gas recirculation are incorporated into combined cycle power plants that utilize either two gas turbines or reheat gas turbines.

Abstract: 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.

Abstract: A waste heat recovery method can provide heat recovery from exhaust gases, full firing of exhaust gases, and auxiliary burning, either simultaneously or independently. Such method is carried out by installing a tube-nested (or heat-absorbing water tube furnace-inserted type) combustion chamber in a boiler of a cogeneration system or combined cycle system or the like which generates both heat and power. The boiler is provided with a combined full firing burner and auxiliary burner confronted by the exhaust gas entrance. This structure allows for elimination of a separate auxiliary chamber and thus has made it possible to provide a waste heat boiler of a simplified structure which is smaller in size and thus occupies less space, at a reduced price and with a greatly expanded heat-to-electricity ratio. Accordingly, the boiler of the invention has a greatly extended range of applications.

Abstract: A combined combustion and steam turbine power plant which includes a steam turbine unit, a boiler unit for supplying steam to the steam turbine unit, and a combustion turbine unit with an exhaust gas duct structure for supplying the turbine exhaust gases to the boiler unit, has at least one heat recovery steam generator arranged in the exhaust gas flow downstream of the boiler unit and connected to the steam-turbine unit so as to supply any steam generated in the heat recovery steam generator to the steam turbine unit.

Abstract: A combined gas and steam turbine system includes a steam turbine having a water/steam loop and a high-pressure stage in the water/steam loop. The high-pressure stage has a preheater and a high-pressure heater connected downstream of the preheater. A gas turbine has an exhaust gas side. A steam generator is connected downstream of the exhaust gas side of the gas turbine. The steam generator includes a firing system producing flue gases flowing in a given direction, the preheater, the high-pressure heater, an intermediate superheater connected downstream of the high-pressure stage, and a medium-pressure heater connected parallel to the high-pressure stage. The medium-pressure heater is disposed in the steam generator between the high-pressure heater and the preheater, as seen in the given flow direction of the flue gases.

Abstract: The present invention has been realized in order to treat noxious and combustible gases, which are exhausted during the start-up operation of a composite coal gasification-power plant and/or released from various safety valves arranged in such power plant and which have hitherto been discharged without treatment into the atmosphere, to make it innoxious and to attain an efficient energy utilization and concerns an improvement of such a composite coal gasification-power plant, which is characterized either in that an additional combustion unit is disposed parallel to the burner of the gas-turbine electric power generating unit and is arranged so as to supply the combustion exhaust gas of this additional combustion unit to as to supply the combustion exhaust gas of this additional combustion unit to the waste heat boiler, or in that an additional combustion unit, operative to effect to burn the noxious and combustible gases exhausted from the burner during start-up and/or those released from safety valves arran

Abstract: There is disclosed an apparatus for burning a waste gaseous stream having a residual heating value represented by a heat of combustion of from 50 to 900 BTU/SCF. to heat an intermediate heat transfer fluid, and to use the thus heated heat transfer fluid to heat diverse fluids in a plurality of serially arrayed heat exchangers at descending temperature levels.

Abstract: There is disclosed an apparatus for burning a waste gaseous stream having a residual heating value represented by a heat of combustion of from 50 to 900 BTU/SCF. to heat an intermediate heat transfer fluid, and to use the thus heated heat transfer fluid to heat diverse fluids in a plurality of serially arrayed heat exchangers at descending temperature levels.

Abstract: An apparatus for generating electrical and/or mechanical energy from at least a low-grade fuel comprises a closed circuit in which steam is formed in a steam boiler fired with low-grade fuel, the steam formed in superheated in a superheater with the aid of heat originating from a heat source in which high-grade fuel is burned, the superheated steam is fed to a steam turbine in which the steam is expanded, thereby delivering work, the expanded steam is condensed in a condensor and the condensed steam is fed back to the steam boiler via a condensate degasser. The combination of forming steam with the aid of heat originating from low-grade fuel and superheating said steam with the aid of heat originating from high-grade fuel provides a process for converting fuel into electrical and/or mechanical energy with a relatively high overall efficiency.

Abstract: A process for low NOX cogeneration to produce electricity and heat which involves combusting fuel to produce a gaseous stream of combustion products, passing the gaseous stream through a turbine to generate electricity, and to produce a gaseous exhaust stream, adding additional fuel to the exhaust stream, to provide a combustible gas stream having fuel in excess of the oxygen in the combustible gas stream, combusting the combustible gas stream in a reducing atmosphere to produce a heated oxygen-depleted gaseous stream, converting at least a portion of the heat in the oxygen depleted stream into steam, adding air to the oxygen-depleted stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel present in the resultant stream, passing the resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, removing heat from the oxidized stream, and venting the resultant cooled stream. An apparatus system for carrying out this process is also provided.

Abstract: In a combined cycle plant boiler an inlet temperature is adjusted or controlled while concurrently modulating the IGV's and the load of the gas turbine and the attemperator of the boiler, and concurrent modulation of the IGV's, the gas turbine load, the attemperator is effected as upon three independent control variables to adjust and/or maintain the boiler outlet temperature independently of steam turbine operation and to maximize gas turbine load control range. Control of the output temperature of one boiler is also managed in relation with the mixed temperature of steam from other boilers fluidly connected to the steam turbines.

Abstract: A steam generator assembly, particularly for use in connection with the mechanical preparation of pulp, for generating pure steam required in a subsequent process, such as drying of proper in a paper machine, by utilizing the condensation heat of contaminated steam coming from a preceding process, such as a grinding process, includes a steam converter and electrical boiler arranged in a common housing to form a unified structure. The steam converter utilizes the condensation heat of the contaminated steam to generate pure steam from water supplied to the converter. The electric boiler is connected in parallel to the steam converter and includes electrodes adapted to generate steam when moistened by water supplied to the boiler from a separate water container in the housing. Selective control of the supply of water to the electric boiler and the extent to which the electrodes are moistened regulates the amount of pure steam generated by the electric boiler.

Abstract: Disclosed is a method, a system and an improved butterfly valve usable therein for recovering energy from a continuous supply of hot pressurized particulate-laden flue gas. This gas is conducted to the atmosphere via a selected one of a plurality of ducts equipped with separate purgable butterfly cut-off valves each located upstream both from the point of gas disposal to the atmosphere and from separate energy recovery devices. Each duct has provision downstream from an associated cut-off valve for insertion of a slip blind crosswise of that duct after closure of the cut-off valve thereby permitting servicing operations on the energy recovery device deactivated by the closed valve or valves. One or more of the recovery devices is usable to supply operating power for components of the system or to other equipment.

Abstract: In a combined cycle power plant having one or more combustion turbines and a steam turbine, a dry catalytic NOx removal module is disposed in each of the turbine exhaust stacks. A waste heat exchanger system includes an economizer coil and a pair of high pressure evaporator coils on upstream and downstream sides of the NOx removal module to generate steam for injection into the turbine combustors and for delivery to a superheater coil upstream from the upstream evaporator coil. A bypass stack across the upstream evaporator coil is damper controlled to regulate the exhaust gas temperature at the entry to the NOx removal module. A downstream low pressure evaporator coil generates steam for induction into the low pressure section of the steam turbine. Superheated steam is supplied to the high pressure section of the steam turbine.

Abstract: In a single cycle combustion turbine power plant, a dry catalytic NOx removal module is disposed in the turbine exhaust stack. A waste heat exchanger system includes an economizer coil and a pair of evaporator coils on upstream and downstream sides of the NO.sub.x removal module to generate steam for injection into the turbine combustors. Bypass stacks across the coils are damper controlled to regulate the exhaust gas temperature at the entry to the NOx removal module. The compressor inlet guide vanes are closed to increase exhaust gas temperature as required after the upstream evaporator bypass flow reaches zero and no longer controls gas temperature. If the inlet guide vanes reach the fully closed position, reductant injection flow is shut off to terminate the NOx removal process under low exhaust gas temperature conditions. A plant afterburner is operated to add heat to the exhaust gas if gas temperature is too low.

Abstract: A combined cycle electric power plant includes gas and steam turbines and a steam generator for recovering the heat in the exhaust gases exited from the gas turbine and for using the recovered heat to produce and supply steam to the steam turbine. The steam generator includes a superheater tube through which a fluid, e.g. water, is directed to be additionally heated into superheated steam by the exhaust gas turbine gases. An afterburner further heats the exhaust gas turbine gases passed to the superheater tube. The temperature of the gas turbine exhaust gases is sensed for varying the fuel flow to the afterburner by a fuel valve, whereby the temperatures of the gas turbine exhaust gases and therefore of the superheated steam, are controlled. A plant load demand error signal is utilized for correcting a coordinated gas turbine load reference and for trimming a feedforward afterburner control signal derived from the sensed gas turbine exhaust temperatures.

Abstract: The waste heat steam generator employs two parallel channels for receiving flows of exhaust gas from a gas turbine. In one channel, the exhaust gas flow is heated by a supplemental burner to a temperature less than 900.degree. C while the flow of exhaust gas in the second channel is heated to a temperature above 900.degree. C. The amount of fuel supplied to each burner is controlled by various control means responsive to the temperature within the steam generator or the temperature of the live steam or by the pressure of the live steam. A distribution means is provided at the entrance to the channel in which the exhaust gas is heated to a temperature above 900.degree. C so as to control the flow therein. The steam generator can be easily adapted to partial load operation by regulating the amount of fuel to the supplemental burners.

Abstract: There is always a danger of slagging on and/or corrosion of the tubes of the highest temperature superheater bank and, if present, reheater bank when burning heavy bunker fuel oil. Therefore a clean fuel burning furnace is provided which is separate from the heavy bunker fuel oil burning furnace and only the combustion gases from burning the clean fuel are used to heat the highest temperature superheater bank and, if present, reheater bank. The clean fuel is preferably provided by a gasifier in which a portion of the heavy bunker fuel oil is pre-combusted to give a clean combustible fuel gas.

Abstract: Described herein is a waste heat steam boiler which is capable of using as secondary combustion air, the exhaust gases from a steam turbine. The boiler has burners which are fed with primary combustion air by an air blower. This air is cool and can be used to keep part of the burners cool. The burners have throats supplied with secondary combustion air from a windbox which receives this secondary air either from the gas turbine or from a forced draught fan. The burner throats are adjustable between an open full quarl position when the secondary air is the gas turbine exhaust and a partially closed position where the effective quarl diameter is reduced when the secondary air is supplied by the forced draught fan.

Abstract: The invention is a valve especially a divertor valve for diverting hot gas to a boiler or to a duct by-passing the boiler and for controlling the amount of gas flowing through the boiler. The valve enables changeover from one flow path to another by rotary movement. The valve member is of plate construction having scraping action on the wall of the valve chamber and allowing 45.degree. angle of flow between inlet and outlet ports.

Abstract: A stem generator with its sections arranged for the limited space available in a marine installation. The heated surfaces are exposed to both the products of combustion of original fuels and the discharge from the prime movers of marine propulsion. The water being vaporized is positively pumped up through the heated surfaces to the short length upper steam separator drum. The superheat surfaces are arranged in modular form so they may be readily replaced and can also be drained of collected liquid when maintenance is required.

Abstract: A combined cycle electric power plant includes gas and steam turbines and a steam generator for recovering the heat in the exhaust gases exited from the gas turbine and for using the recovered heat to produce and supply steam to the steam turbine. The steam generator includes a superheater tube and a steam drum from which heated steam is directed through the superheater to be additionally heated into superheated steam by the exhaust gas turbine gases. An afterburner serves to further heat the exhaust gas turbine gases passed to the superheater tube and a bypass conduit is disposed about the superheater tube whereby a variable steam flow determined by a bypass valve disposed in the bypass conduit may be directed about the superheater tube to be mixed with the superheated steam therefrom, whereby the temperature of the superheated steam supplied to the steam turbine may be accurately controlled.

Abstract: In a combined cycle power plant, gas turbine exhaust gas is passed through a heat recovery steam generator (HRSG) wherein it may be reheated upstream from a boiler tube section prior to passing through the boiler tube section in a non-contact heat exchange relation with a feedwater supply to produce steam for driving a steam turbine. A plurality of air-atomized, liquid fuel wall burners are utilized, each in combination with a "vee"-shaped flameholder to heat the gas turbine exhaust gas. Each wall burner may be disposed in a recessed opening in the HRSG duct wall and each wall burner has a nozzle portion which may be directed upstream relative to the exhaust gas flow. Each flameholder is approximately parallel to its respective wall burner nozzle axis having one end fixed to the duct wall, upstream from the nozzle axis, and a free end disposed within the HRSG duct.