Abstract: An apparatus and method for recovery of waste heat in a boiler system, wherein heat from the low pressure steam in the feed water tank, which otherwise would be lost through dissipation, is used for other applications. Particularly, the waste heat energy recovered in the form of low pressure steam can be used to heat make-up water for the boiler system.

Abstract: A back-up boiler system for a solar thermal power plant (201) for transferring solar energy into electricity, said back-up boiler system comprising a combustion chamber (70) and a convection section (80) in fluid connection with said combustion chamber (70), wherein in the convection section (80) at least a first heat exchanger (92) is provided for heating a molten salts mixture of the solar thermal power plant and a second heat exchanger (90) for pre-heating boiler feed water of the solar thermal power plant, wherein the back-up boiler system (25) is configured to allow selection between only providing heat to the first heat exchanger (92), only providing heat to the second heat exchanger (90) and providing heat to both heat exchangers (90, 92), preferably dependent on availability of solar radiation and/or dependent on demand of power generation.

Abstract: A system providing for heat recovery from exhausted flue gas in a steam generator is described comprising a flue gas outlet conduit defining a flow path for flue gas from a flue gas outlet of a steam generator to a flue gas conduit junction point; a flue gas primary conduit defining a flow path for flue gas from the junction to a primary air preheater; a flue gas secondary conduit defining a flow path for flue gas from the junction to a secondary air preheater; wherein a steam generator process fluid heat exchanger is disposed within the flow path of the flue gas primary conduit upstream of the primary air preheater to recover some heat from the flue gas in advance of the primary air preheater. A method implementing the flow principles embodied in such a system is also described.

Abstract: A plant (10, 110) for the production of electric energy comprises a fuel boiler (11) in which a fluid is heated in order to produce steam, a turbine (15) which is connected to an electric generator (16) and to which said steam is conveyed, and a condenser unit (19) which re-condenses the fluid output from the turbine so that it may be conveyed back to the steam generator. The return fluid along the path from the condenser unit (19) to the boiler passes through a preheating unit (22) which receives heat from the turbine steam bleed-offs (23) and from a thermodynamic solar field (25). By making suitable use of the heat produced by the solar field (25) and contained in the heat-carrier fluid which passes through it, it is possible to increase the overall efficiency of the plant (10, 110).

Abstract: In a coal fired power plant (17) incorporating a feed-water heater (10), energy is provided to the feed-water heater by pumping geothermal hot water through supply and return pipes (15, 16) from a geothermal reservoir (14) located beneath an adjacent coal seam (19). The coal seam acts as an insulating layer, increasing the temperature of the geothermal reservoir (14). Solar heat collectors (21) and (25) can also be provided to boost the temperature of the geothermal hot water and/or the feed water.

Abstract: Methods and systems generate steam and carbon dioxide mixtures suitable for injection to assist in recovering hydrocarbons from oil sands based on concentration of the carbon dioxide in the mixtures as influenced by temperature of water introduced into a direct steam generator. Increasing temperature of the water to above 200° C. before introduction into the direct steam generator may utilize heat from an electrical power generation unit. Enthalpy of this preheated water impacts amount of fuel needed to burn in the direct steam generator and hence the concentration of the carbon dioxide, which may be below 11% by mass percent of the steam.

Abstract: A steam generator is provided. The steam generator has a combustion chamber having a peripheral wall formed at least partially from gas-proof, welded steam generator pipes, at least two additional inner walls formed at least partially from additional steam generator pipes which are arranged inside the combustion chamber. The inner walls are connected one behind the other on the flow medium side by an intermediate collector. The steam generator has a high service life and is reliable. The flow medium on the inlet of the inner wall upstream of the intermediate collector has a lower temperature than that of the flow medium on an inlet of the peripheral wall.

Abstract: The present invention discloses a hermitically sealed solar water heater system and operation method for generation of electricity from thermal power plant. Water storage tank (1) is hermitically sealed by diaphragm (13) to prevent feed water contamination. Solar energy based water heater (2) preheats feed water and raises water temperature close to the boiling point. The feed water heater by trapping the waste heat from the exhaust gases further heats the feed water and is pumped to the boiler and where it is converted to steam. The steam impinging on the turbine blades drives it and generates power from the generator. The steam condenses in the condenser and the water coming out of condenser is pumped to the overhead water tank and the process of power generation is continues uninterruptedly.

Abstract: Modularized, superheated steam generators comprise a steam module (46), a thermocouple module (41), and an electrode module (45) assembled within a containment enclosure (66). The multi-stage steam module (46) comprises a plurality of first stage pressure vessels (77) surrounding and feeding a second stage pressure vessel (78). The steam module (46) is coaxially surrounded by insulation (48) disposed within a cylindrical shroud (72). The electrode module (45) radiantly heats the steam module with resistive heating elements (119). The thermocouple module (41) includes thermocouples monitoring first stage temperatures within and between pressure vessels (77). PLC computer SCADA software (600) operates the generators. Thermocouple data is analyzed to control heater temperatures, the water feeding system (340), and outputted steam temperature.

Abstract: Modularized, superheated steam generators comprise a steam module (46), a thermocouple module (41), and an electrode module (45) assembled within a containment enclosure (66). The multi-stage steam module (46) comprises a plurality of first stage pressure vessels (77) surrounding and feeding a second stage pressure vessel (78). The steam module (46) is coaxially surrounded by insulation (48) disposed within a cylindrical shroud (72). The electrode module (45) radiantly heats the steam module with resistive heating elements (119). The thermocouple module (41) includes thermocouples monitoring first stage temperatures within and between pressure vessels (77). PLC computer SCADA software (600) operates the generators. Thermocouple data is analyzed to control heater temperatures, the water feeding system (340), and outputted steam temperature.

Abstract: There is disclosed a method of generating superheated steam for use in power generation. The method comprises: (a) preheating feed water to a temperature below its boiling point; (b) boiling the preheated feed water to produce steam; and (c) superheating the steam. The feed water is boiled by heat exchange with a heat transfer fluid which has been heated by heat collected in a first solar radiation absorption device. In addition, one or other or both of the preheating and superheating is carried out by direct heating in a further solar radiation absorption device or devices. The invention also relates to an apparatus for generating superheated steam for use in power generation.

Abstract: The invention provides a method of recovering heat from hot produced fluids at SAGD facilities that utilize wellpad steam generation such as Direct Steam Generators (DSG).

Abstract: The invention relates to an integrated device for separating air and heating a gas in the air resulting from said air separation, comprising: an air separation device (9); a heat exchanger (13, 43); a channel for conveying the gas in the air to the heat exchanger; and a channel for conveying water to the heat exchanger, the water-conveying channel being connected to the water inlet or water outlet of a water preheat exchanger (5) or a water deaerator (27). According to the invention, the preheat exchanger and/or the deaerator are connected to an oxy-combustion boiler (19) in order to convey water to and from the boiler, said boiler also being connected to the separation device in order to receive an oxygen-enriched gas (17).

Abstract: The invention relates to a method for operating a forced-flow steam generator operating at variable pressure and at a steam temperature above 650° C.

Abstract: One exemplary embodiment of the present invention can be a fired heater for a hydrocarbon conversion process. The fired heater includes inlet and outlet headers or manifolds, a set of heater tubes with each heater tube having an inlet and an outlet, at least one restriction orifice adjacent the inlet of at least one heater tube. The restriction orifice may be within the inlet manifold and adjacent the inlet of a heater tube, or between the inlet manifold and the inlet to the heater tube. A process may include passing a hydrocarbon stream through the fired heater described herein during the course of operating a hydrocarbon conversion process.

Abstract: The invention provides a method and system for conducting a continuous operation, flowing vapor phase decontamination in either an open loop or a closed loop. Using the method, a multi-component liquid decontaminant is vaporized and delivered into, through and out of a sealable enclosure by means of a carrier gas that is flowing into, through and out of said sealable enclosure. After leaving the enclosure, the vapor is captured in a cold-water bath and decomposed. The invention humidifies the carrier gas by passing it through a temperature controlled water bath to warm, or to cool, the carrier gas as necessary in order to bring the carrier gas to the desired temperature and humidity before it is combined with the vaporized sterilant and allowed to flow into the sealable enclosure. The concentration of the vapor sterilant and the percent saturation of the vapor sterilant are simultaneously controlled by controlling the rate at which the carrier gas flows and the rate at which the liquid sterilant is vaporized.

Abstract: The present invention relates to a water warming system and method for warming a hot water heater supply line that includes: a s-shaped piping connected to a water supply line; an insulating compartment surrounding the s-shaped piping; a warm wastewater input into the insulating compartment and a wastewater output from the insulating compartment; and an output from the s-shaped piping connected to a hot water heater. The water supply line inputs either ambient water or cool water into the s-shaped piping. The warm wastewater generated within a home provides a source for the warm wastewater.

Abstract: The steam generator includes a feedwater delivery device at an upper axial end of an annular space between an outer shell and a bundle wrapper of the steam generator. The feedwater, delivery device includes a header (11) having a shell of toroidal general shape, at least one feed pipe for the header and feedwater distribution means (14) in the upper part of the annular space of the steam generator. The feedwater distribution means (14) include a plurality of openings (17) that pass through the upper part of the shell of the toroidal header (11) and are distributed circumferentially on the wall of the header and a plurality of tubes (15) fixed via a lower end part at an opening (17) of the header (11). Each of the straight tubes (15) includes an upper end part through which openings (20), such as water passage slots, pass and a cap (16) fixed to the upper end of the tube (15) surrounding, with a radial clearance, the upper end part of the tube (15).

Abstract: A raw fuel vaporizing apparatus comprising: a vaporizer for vaporizing liquid raw fuel; a raw fuel introducing device for introducing the liquid raw fuel into the vaporizer; a catalyst combustor into which fuel and air are supplied for catalytic combustion, the catalyst combustor generating heat in the presence of a catalyst and supplying the resulting heat to the vaporizer to vaporize the liquid raw fuel; a fuel introducing device for introducing the fuel into the catalyst combustor; an air introducing device for introducing the amount of the air suitable for catalytic combustion into the catalyst combustor; a heat transferring gas introducing device introducing heat transferring gas into the catalyst combustor to transfer heat retained by the catalyst combustor to the vaporizer; and a controller increasing the amount of the heat transferring gas through the heat transferring gas introducing device when the amount of vapor generated in the vaporizer is increased.

Abstract: A Pressure Relief System for attachment to pressurized vessels, containers, reactors, boilers, etc., utilizing liquid(s) as a working part of the Pressure Relief System.

Abstract: A combustion apparatus for use as a boiler wherein RDF is burned as the fuel, or as an incinerator for burning municipal waste. The apparatus is diminished in the quantities of NOx produced, permits a dust collector to achieve an improved efficiency in separating off a free-flowing medium and assures a fluidized-bed furnace of effective fluidization of a medium. The apparatus comprises a fluidized-bed furnace (1), a cyclone (2) disposed downstream from the furnace (1) for separating a free-flowing medium and a combustion residue discharged from the furnace (1) from combustion gases and collecting these solids, and a medium-residue return channel (3) provided between the cyclone (2) and the furnace (1) for returning the free-flowing medium and the combustion residue collected by the cyclone (2 )to the furnace (1) therethrough.

Abstract: The present invention is drawn to a device for heating liquid feed for veal calves, although this device may have wider application. The present invention is a pre-heater system used to raise the temperature of liquid feed that is being pumped from cold storage to a mixing tank prior to being fed to an animal. Additionally, the present invention is arranged to independently supply heated water externally of the system.

Abstract: A hot water heating system having a water tower with a cold water inlet at the upper end and a hot water outlet at the lower end has a large diameter combustion inlet opening in the sidewall. A combustion chamber is secured to the water tower at the combustion inlet so that products of combustion of fuel consumed in the combustion chamber pass into the water tower and are exhausted through a vent. An outer shell surrounds the combustion chamber providing an annular chamber having a water inlet. A port communicates the upper interior of the annular chamber with the interior of the water tower. Water is circulated from a hot water storage through the annular chamber and through the port into the interior of the water tower. The recirculated water thus accomplishing the dual functions of cooling the combustion chamber and salvaging heat extracted from the combustion chamber to augment the heat of the water in the storage tank.

Abstract: A fuel cell and a boiler are coupled in such a manner that the water used to capture excess heat generated by the fuel cell is used for boiler feedwater heating. In one embodiment, steam generated by the boiler is used in an operation that converts the steam to condensate, and the condensate is returned to the fuel cell for use as a heat sink for the thermal energy generated within the fuel cell unit.

Abstract: A method of controlling the reheat steam temperature in a circulating fluidized bed combustion system wherein the circulating solids are cooled in a heat recovery fluid bed system containing reheat heat exchange surface. The rate of heat transfer and thus the reheat steam temperature are controlled by adjusting the flow rate of fluidizing air to the portion of the heat recovery fluid bed system containing the reheat surface.

Abstract: A distillation apparatus includes a heating device, an inlet for medium to be distilled, a vapor outlet, a distillation space between the distillation medium inlet and the vapor outlet and a drain for the separate components of the solvent, arranged in the bottom part of the distilling space and extending from same. In a heating vessel, which is able to be filled with a heating medium to be heated by the heating device, there is a downwardly extending down tube joined with the inlet and an up tube extending upwards to the vapor inlet. During operation the two tubes are surrounded by heating medium and form the distillation space. The drain is arranged under the junction between the up and down tubes and is provided with a U-trap.

Abstract: A compact and maintenance-free means and method of regenerating the sensible heat from flue gases of fossil fuel furnaces by heat exchange through two circular layers of rock beds rotating under two semi-circular mantles with the first mantle applying hot flue gases to the beds and the second withdrawing preheated ambient air needed for combustion by said furnaces. When used for power plant flue gas treatment, layers of acid-resistant pipes containing boiler feedwater are sandwiched between the two rock bed layers to usefully recover the heat units arising from moisture condensation. The enormous water of condensation collects flyash and sulphur dioxide thus removing these pollutants from the stack gases. The heavy rock beds rotate slowly beneath the fixed mantles in a circular, pan-shaped, steel vessel floating on and cooled by a circular pond of water. Friction of rotation is minimal and gas leakage principally prevented by liquid seals. When flue gas temperature rises, as above 600 degrees F.

Abstract: Device for preventing thermal stratification for a steam generator feed pipe. A fixed helix (14) downstream of a rising break (12) of the pipe subdivides its interior into twisted channels. The cold water entering at a low flame rate is blocked upstream until a predetermined height (h) is reached and completely fills an upstream part (11) to be protected against thermal gradients.

Abstract: An oil and gas fueled hot water heater system having improved efficiency and performance embodies water and air supply jackets, cold and hot water insulating check valves, and flow directors and restrictors for the hot combustion gas generated by the heater burner which gas passes through a central flue in a water storage tank and is then exhausted through an exhaust vent to atmosphere. The water supply jacket closely surrounds the central flue and receives supply water at the top thereof and discharges same to the bottom of the storage tank thereby increasing the heat transfer characteristics of the heater. The air supply jacket surrounds the exhaust vent and air is drawn in through the top of the jacket along the exhaust vent for preheating and then is directed to the burner to support combustion. The cold and hot water insulating check valves are positioned in the water supply and outlet lines to reduce heat transfer through such lines when the heater is idle.

Abstract: An evaporating apparatus includes an evaporator (E) for converting a liquid into vapor and a preheater (2) for heating the liquid before it is fed to the evaporator (E). A pump (6) for feeding the liquid to the preheater (2) and another pump (8) for pressurizing the liquid passing from the preheater (2) to the evaporator (E) are provided, where the former maintains the liquid at a saturation pressure with respect to a temperature slightly higher than a saturation temperature (t.sub.o) at the preheater outlet, and the latter serves to raise the liquid pressure to a saturation pressure with respect to a desired evaporation temperature (t.sub.2). Rate of flow of a heating medium for the preheater (2) is controlled so that its temperature (t.sub.w3) is slightly higher than a liquid preheater outlet temperature (t.sub.ex). Thus, in the preheater (2), the liquid temperature (t.sub.ex) is maintained lower than saturation temperature (t.sub.o), ensuring a greater amount of heat transfer by subcool boiling.

Abstract: A vacuum vapor transport control system and method for controlling the rate of vapor flow from a reagent reservoir into a vacuum system through an orifice calibrated as to size or flow rate using a high purity fixed gas and vapor provided from multiple reservoirs or mixed vapor provided from a single reservoir.

Abstract: A high efficiency gas hot water heater has a vertical cylindrical water tower and a cylindrical combustion chamber secured to the wall of the vertical water tower and extending horizontally therefrom. The combustion chamber has means at the outer end for the injection of gas and air therein, the products of combustion of gas and air produced in the combustion chamber flowing into the vertical water tower which has, at its upper end, a flue. A generally horizontal water distributor is positioned within the water tower adjacent to the top. A water jacket surrounds the combustion chamber with piping providing a water inlet into the water jacket and from the water jacket into the water distributor so that the products of combustion of the gas and air in the combustion chamber flow into the vertical water tower and upwardly therethrough as water flows downwardly therethrough.

Abstract: An automatic water heater system having, contained in a tank, a plurality of vertically extending spiral flame tubes surrounded by substantially vertically extending heat tubes which join the top ends of the spiral flame tubes to form a common exhaust outlet for both sets of tubes, thereby greatly increasing the surface area contact between the water and transfer medium. The heat tubes are especially designed to provide an outlet drain for possible condensation that can develop so as not to drain out through the flame tubes and onto the flame. A heat trap, to capture heat from the hot flue gases otherwise lost by normal passage up through the chimney, may be provided, as well as a blower in the exhaust outlet. The above described structure can be assembled either as a combination heating and storage tank in a single unit, or as a separate component heating unit connected to the storage tank located alongside it.

Abstract: A steam generator has a pressure vessel containing a stack of exchange tubes and a feedwater header of ring shape connected to a feed water intake pipe passing through the wall of the vessel. A horitzontal section of the pipe contains at least one deflector comprising an axial hub and several helical blades connecting the hub to the wall of the pipe. The blades have a length which represents at least half a winding pitch if the deflector is to counteract thermal stratification only, at least 1.5 winding pitch if for avoiding pressure surges.

Abstract: A heat exchanger with straight tubes for convenient cleaning and repair is constructed with superior heat exchange capabilities. The heat exchanger has an outer shell with a fluid entry and exit and end plates which support one or more tubes with a fluid entry and fluid exit for each tube, the tubes having both an internal turbulence inducing structure and an external fin structure with periodic baffles for maximizing the heat exchange surface area and the contact of the exchange fluids with the exchange area.

Abstract: A heat exchanger for the cooling of hot gases from the synthesis of ammonia. The heat exchanger has tubes which are bent into U-shape and are arranged within a shell. The tubes are inserted into a tube plate. An exit chamber and an entry chamber are arranged therein for the gases to be cooled adjacent the tube plate. Separating walls are arranged within the shell for the formation of closed preheating chambers and enclose the exit limbs of all tubes. The entry limbs extend within a separated middle space. A preheating chamber and the middle space are provided with separate connections for their own water passage.

Abstract: The invention relates to a process and to a heat exchanger (8) intended in particular for performing the process, for operating a high-pressure boiler (1), having consuming units (3', 3", 3'") connected to the high-pressure boiler (1), the condensate from which units is returned to a condensate tank (5). By means of a feed water pump (7), feed water is fed to the boiler (1) and the condensate and the feed water are then fed to a heat exchanger (8) upstream of the condensate tank (5). According to the invention, the hot condensate is fed to the free space of the heat exchanger (8), and the feed water which is to be heated is pumped to the heat exchanger (8), passed helically from the cold to the warm zone in the heat exchanger (8) and carried from the heat exchanger (8) into the boiler (1). As a result of this heating up of the feed water, the heat contained in the condensate becomes economically useable, resulting in substantial savings in heat medium for the boiler.

Abstract: Support points (15) are provided in the duct-shaped portions (17-22) of the desuperheater casing, at which points the serpentine tubes (25) of the preheater tube-bundle are fixed in a direction, at right-angles to the longitudinal direction of the tubes, by means of support strips (24) which bear against the tubes in a manner permitting movement in the longitudinal direction. The support strips (24) are composed of sheet steel, and possess spacer tabs (26) which extends at right-angles to the plane of the sheet steel. The ability of the support strips to shift relative to the serpentine tubes (25) is limited by supporting crosspieces (22) on two opposite web sheets (21) belonging to the support point (15).

Abstract: A novel low C-Cr-Mo steel having an excellent weldability and a high erosion-corrosion resistance under wet steam, which consists of, in % by weight, 0.02-0.14% of C, not more than 0.90% of Si, 0.30-0.80% of Mn, 0.70-1.60% of Cr, 0.40-0.70% of Mo and the remainder being substantially Fe. This novel steel is a very excellent material for fabricating the portions in the feed-water heater, for example, for a nuclear power generation plant, the portions being used under wet steam condition. The above described weldability and erosion-corrosion resistance can be improved by additionally adding the second components of Cu, N, or B, the third components of Nb or V or the fourth components of Al, Ti or Zr in the respectively defined amounts.

Abstract: A once-through steam generator has both radiant and convection sections. The flue gases discharged from the convection section are passed through a wet scrubber to remove both sulfur oxides (SO.sub.x) and particulate matter. The feedwater to the convection section has its temperature controlled by the temperature of the flue gases discharged from the convection section, reducing the temperature of the feedwater by the use of a feedwater exchanger, as the convection section progressively fouls due to particulates in the flue gases. An additional heat exchanger upstream of the feedwater exchanger and convection section which scavenges additional heat from the wet scrubber liquids while the temperature of the flue gases into the scrubber are lowered to a temperature equal to or less than the water dew point temperature of the flue gases entering the scrubber.

Abstract: A cyclic velox boiler is described wherein solid carbonaceous fuels are burned in pressure vessel containers by cyclic compression and expansion with air or with air and steam as usual gas reactants. During compression air is forced deeply into the pores of the solid fuel and rapid primary burning to carbon monoxide results due to the large internal pore area available. During expansion the primary reacted gases emerge from the pores to mix and react fully with secondary air retained outside the pores in the container. Rapid and complete burning of the char fuel can be obtained in this two step, cyclic burning process and net useful mechanical work can be obtained from an expander engine. The containers and portions of the expander are cooled with water and the resulting steam can be used to generate additional work output via a steam power cycle.

Abstract: Disclosed are methods and apparatus for heating and utilizing fluids by the use of vapor generators of the kind in which a flowing fuel/air mixture is combusted in the presence of a stream of feed water to produce a stream of steam and non-condensibles, preferably at low pressure. This hot stream is then heat exchanged with a stream of the fluid desired to be heated and utilized, to heat it to the level desired for use, including partly or completely vaporizing it, if the use so requires. The fluid may be divided into two or more streams during the heat exchange, with different amounts of heat delivered into each stream. Preferably, the heat exchange is so conducted as to condense the steam from the stream of steam and non-condensibles, and the condensate so formed is selectively recycled to the vapor generator as feed water.

Abstract: Disclosed are methods and apparatus for the controlled heating and utilization of fluids by the use of vapor generators of the kind in which a flowing fuel/air mixture is combusted for heating a stream of feedwater to produce a stream of steam and non-condensibles, preferably at low pressure. The hot stream is then heat exchanged with a stream of the fluid desired to be heated and utilized, to heat it to the level desired for use, including partly or completely vaporizing it, if the use so requires. The fluid may be divided into two or more streams during the heat exchange, with different amounts of heat delivered into each stream. Preferably, the heat exchange is so conducted as to condense the steam from the stream of steam and non-condensibles, and the condensate so formed is selectively recycled to the vapor generator as feedwater.

Abstract: In a method of heat extraction from an aqueous carrier medium through its expansion, the expansion is undertaken step by step in a number of expansion stages arranged consecutively as regards the flow of the medium. The vapor produced in each expansion stage is removed from the stage, and the individual vapors are subjected, respectively, parallel to each other, to a thermal utilization or revalorization.According to one embodiment, the carrier medium is boiler feed water, which is circulated via a heat absorption zone and through the expansion stages. The vapor produced undergoes thermo-compression and is fed to a common steam bar. The heat absorption zone, heat exchangers are heated by a source of waste energy. A produce of this method is a pure water vapor.

Abstract: In order to improve upon the prior arrangement of a valve within a liquid distributor head for a mixing pre-heater degasifier it is proposed that a valve containing a valve plate, valve shaft, valve spring and spring plate, is arranged within the mixing pre-heater centrally within a deflection screen or baffle and at the same time the valve is surrounded by a protective housing in order to prevent that, in the event of possible rupture of the valve spring any broken pieces thereof will drop into the mixing pre-heater.

Abstract: A thermodynamic method is described and claimed for improving the quality of wet steam produced by conventional and once through type boilers. Moisture entrained with such steam is first separated in a steam-water separation vessel. The separated moisture is thereafter vaporized by pressure reduction and flashed to form lower pressure steam and condensate containing dissolved solids. The condensate is utilized to preheat fresh boiler feedwater. The lower pressure steam is condensed and supplements the boiler feedwater to form a hotter combined net feedwater stream containing reduced quantities of dissolved solids. Practice of the method, in association with commercially available boilers producing saturated to moderately superheated steam at temperatures of up to about 970.degree. F. and steam pressures of up to about 2,900 psig, has resulted in increases in the quality of the steam produced from about 70% to about 99% (substantially dry steam).

Abstract: A boiler economizer includes a first heat exchanger disposed in a boiler flue and a second heat exchanger which is external. Boiler feedwater is delivered in series to the first and second heat exchangers before passage to the boiler. A flow controller directs a first portion of the boiler feedwater directly to the first heat exchanger and a second portion is first delivered through the second heat exchanger where it is passed in a heat exchange relation with the feedwater exiting the first heat exchanger. The flow controller is positioned by a temperature transponder which is responsive to the temperature of the discharge flue gases and the feedwater entering the first heat exchanger.

Abstract: A method of pre-heating feed water for boilers is disclosed which utilizes the exchange of heat between the tube side of a heat-exchanger which contains de-salinated and de-ionized water and the shell side which contains hydrocarbon vapors boiling in the range of 90.degree. to 150.degree. C. The tubes are made of carbon steel with their outer surfaces aluminized.

Abstract: A closed pressurized feed water system supplying flash steam to a lower pressure process and with no steam loss in the closed system. The flash steam delivered to the lower pressure process is sufficient to reduce the pressure in the feed water system so that a steam trap in the closed system will operate and permit the hot condensate to be returned to the boiler. Also, new make up water may be added to the system to compensate for any steam loss. In the high pressure closed system about 96.68% of the condensate is returned to the boiler and only about 3.32% is needed for new make up water.

Abstract: A feed water preheater has an integral desuperheater and an integral supercooler through which passes the feed water tube bundle. To prevent the penetration of steam into the supercooler at the point where the feed water tube bundle passes from the supercooler into the condensation space through a support plate, the tubes of the tube bundle are surrounded by sleeves which are fixed to the support plate. Steam flowing through the sleeves condenses and fills the sleeves to prevent the entry of steam into the supercooler. Sleeves are also provided at points where the tubes pass between the desuperheater and condensation space to reduce the velocity of steam traveling from the former to the latter. The latter sleeves can be oriented vertically in the case of a vertical preheater, as long as they are longer than the thickness of condensate disposed on the support plate in the condensation space.