Abstract: A furnace for heating a process fluid stream which includes means for efficiently controlling a flow of the process fluid stream through an adjunct loop of the fluid stream. The adjunct loop comprises a heat exchange system in which a portion of the process fluid stream collects heat from flue gases being emitted from the furnace and donates heat to combustion air being used in the furnace. Valve means is positioned downstream of a pump and in connection with the fluid stream in order to constantly replenish a small portion of fluid in the adjunct loop with fresh process fluid. The positioning of the valve means downstream of the pump permits more efficient control of the heat exchange system. One form of valve means may be a valve which will permit a small amount of fluid to continue to flow between the fluid stream and the adjunct loop during a non-operating mode of the adjunct loop heat exchange component.

Abstract: Transfer waste water from wash cycle of dishwasher to collection tank beneath heat exchanger surrounding hollow central space, pass waste water through dual tube heat exchanger in countercurrent relation to cool feed water for hot water heater in central space of heat exchanger, supply heat to water in heater, then hot water to dishwasher rinse. May circulate feed water downwardly through outer space of heater, formed by partition, to lower end of inner space, in which heat is supplied by electrical immersion heaters. Ends of tank of hot water may be semi-oval, semi-elliptical or the like, while partition may be sufficiently close to bottom of tank to produce a wire-drawing effect as inlet water flows from outer to inner space, thereby maintaining light or small particles which fall off electric heaters in circulation, so that such particles will be removed with hot water. Heavier particles will collect in bottom of tank and may be drained periodically.

Abstract: Exhaust gas treatment method and apparatus extract heat from an exhaust gas by operating in a water-condensing mode which allows more heat to be recovered, removes particulate matter and condensed acid from the exhaust gas, and washes heat exchange surfaces to keep them clean and wet to improve heat transfer. Systems for heating water, air, and both water and air are disclosed. Methods of constructing and assembling improved heat exchangers are disclosed.

Abstract: A method and an apparatus for the heat recovery from plants in which waste heat is produced at different waste heat sources and fluids are emitted at different temperatures, said method and said apparatus striving after a total optimization of the heat recovery without efficiency losses caused by missing instantaneous compensation between the amount produced waste heat and the need thereof. Said method comprising the steps of collecting waste heat in emitted fluid or fluids at every waste heat source of group of mutually similar waste heat sources and assorting said waste heat with regard to temperatures and as required accumulate it at the highest temperature as possible. Collected heat is then fed back directly or indirectly via the accumulators to the heat requiring unit the temperature need of which is with as low value as possible below the temperature of the feed-back heat. Said apparatus is characterized in that said waste heat sources (M.sub.1 -M.sub.

Abstract: A heat exchanger system exhibits an improved coefficient of heat transfer over a conventional convection heat exchanger while maintaining the beneficial high temperature driving force of conventional convection heat exchanger. A plurality of heat extraction means are provided in heat flow communication with a plurality of shallow beds of particulate matter, which beds are fluidized by a heat-laden gas stream.A method for extracting heat from a heat-laden gas stream is also disclosed.

Abstract: An energy recovery ventilator adapted to be mounted on a roof and adapted to be connected to the outlet of an exhaust air duct of a building ventilation system and the inlet of an air supply duct of a building ventilation system. The energy recovery ventilator includes a housing having an exhaust air chamber and a supply air chamber separated by a divider wall. A circular heat transfer wheel is position in the housing, a portion of the wheel being housed in the exhaust air chamber and a second portion of the wheel being housed in the supply air chamber, and the heat transfer wheel is caused to rotate about a central axis. An exhaust fan is housed in the exhaust air chamber and causes exhaust air to be pulled through the exhaust air duct and the heat transfer wheel and to be exhausted from the housing.

Abstract: A heat exchanger, e.g. that used in an air-conditioner, having a plurality of spaced plate-fins with narrow distance in parallel and a plurality of heat transfer pipes passing through said fins, said fins being coated with an aqueous coating composition comprising 100 parts by weight of a resin composition for water paint in solids content, 5 to 95 parts by weight of a surface active agent and 5 to 65 parts by weight of synthetic silica and baked at a temperature of 120.degree. C. to 200.degree. C. for 10 to 40 minutes to give a coating film of 3 to 20 .mu.m, has excellent hardness and corrosion resistance without damaging hydrophilic properties.

Abstract: A regenerative room air exchanger for use in a house has a first vertically disposed conduit through which room air flows to be exhausted, the first conduit including a first set of vertically disposed channels, a second vertically disposed conduit through which fresh air flows to the room, the second conduit including a second set of vertically disposed channels with the first and second sets of channels being interdigitated and in counterflow heat exchange relationship with each other, and a jacket surrounding and spaced from the interdigitated channels to form a third vertically disposed conduit between the jacket and the channels, the third conduit being in fluid communication with the first conduit. An exhaust blower is in fluid communication with the first conduit and an inlet blower is in fluid communication with the second conduit.

Abstract: A ventilating device for an automotive vehicle mounted in a rear portion of the vehicle comprises an atmospheric air passageway for introducing atmospheric air from the outside of the vehicle into a vehicle compartment, and an internal air passageway provided in a manner to cross the atmospheric air passageway for leading the air in the rear portion of the vehicle compartment to the outside of the vehicle. The atmospheric air passageway is arranged to cause the atmospheric air to be blown from the rear to the front of the vehicle compartment, so as to improve ventilation performance in the rear portion of the compartment. Further, a total heat exchanger is mounted at the crossing portion of the two passageways for effecting exchange of both sensible heat and latent heat between the atmospheric air flowing through the atmospheric air passageway and the air flowing through the internal air passageway.

Abstract: Exhaust gas treatment method and apparatus extract heat from an exhaust gas by operating in a water-condensing mode which allows more heat to be recovered, removes particulate matter and condensed acid from the exhaust gas, and washes heat exchange surfaces to keep them clean and wet to improve heat transfer. Systems for heating water, air, and both water and air are disclosed. Methods of constructing and assembling improved heat exchangers are disclosed.

Abstract: A device for heating fluid with the exhaust gases from a furnace or stove includes a coiled fluid conduit mounted within the exhaust conduit and means such as baffles for directing the exhaust gases through and around the coiled fluid conduit. In one embodiment, the fluid in the coiled conduit is water from a cold water source which, after passing through the coil and being heated by the exhaust gases, flows to a water heating tank in a pre-heated condition.

Abstract: A gas condenser apparatus and method is described employing two heat exchanger stages for condensing water vapor and other contaminates, such as organic solvents, out of hot air or other treated gas by means of a cooling gas which is provided by feeding back the treated gas through the cooling passages of such heat exchanger stages after removal of the water and solvents. The heat exchangers are of the counterflow type so that the treated gas and the cooling gas flow in opposite directions therethrough. Preferably, water vapor is removed from the treated gas by condensing it in the first stage and the solvents are removed by condensing them in the second stage thereby separating the condensed water and solvents. Auxiliary cooling coils are provided at the input of the first stage and at the output of the second stage for further cooling of the treated gas.

Abstract: A heat exchanger comprising a coil assembly mounted in a broiler used in restaurants for example where the temperature of the broiler is about 500.degree. F., such coil assembly being connected to an intermediate holding tank into which cold water is fed from a public water supply through a downwardly extending pipe in the intermediate holding tank having its discharge opening near the bottom of the tank. An outlet port is located slightly above the level of the discharge opening of the downwardly extending pipe, and a conduit is connected between the outlet port of the holding tank and the coil assembly mounted in the broiler, with a pump connected in this conduit to pump cold water from the bottom portion of the intermediate holding tank to the coil assembly mounted in the broiler. A return conduit leads from the coil assembly back to an inlet port of the intermediate holding tank located in the upper part of such tank whereby water which has been heated to about 100.degree. F. from about 40.degree. F.

Abstract: A radiant tube to be heated by high-temperature gases supplied from its one end. The tube supplys a heat radiation by being thus heated. The gases used for the heating are discharged from the other end of the tube. Inside the tube a heat exchanger is provided in the proximity of the gas outlet of the tube so as to recover thermal energy from the used gases before they come out from the outlet.

Abstract: A device for air control for an air ventilated room is provided with an outer pane on its weather side and at its room side with an inner pane. An air channel is formed between the panes for the exhausted room air and a fresh air channel with a weatherside fresh air suction opening and a room side fresh air discharge opening is provided in connection with the air channel. The air channel is connected to a weather side exhaust air opening on its downflow side and is also in connection with a heat exchanger disposed in front of the weather side exhaust air opening through which the exhaust air can transmit heat to the fresh air flowing through the fresh air channel. The air control device is a compact structural unit and is exclusively disposed on the inside of the room. The compact structural unit comprises a separate air control box and a ventilator box.

Abstract: A heat exchanger for energy efficient ventilation of buildings is described. The heat exchanger has a core structure defined by a plurality of rectangular sheets of an extruded, cellular plastic material disposed in parallel, spaced-apart relationship. The cells of the sheets provide a first set of flow paths extending between ends of the core structure for use in passing cold fresh air. The spaces between the sheets are sealed at each end of the core structure, and a cellular plastic sealing material is wrapped about the sides, top and bottom of the core structure and apertured at opposite ends to access the spaces, so that the spaces between the sheets define a second set of flow paths for passing stale warm air. A drainage aperture is provided in an inner face of a bottom sheets of the sealing sheet, where condensation tends to accumulate. The drainage aperture permits condensation to escape through the cells of the bottom sheet.

Abstract: The invention relates to the charging of pressure gas containers used for the storage of hydrogen, on the basis of a gas/solid matter reaction. In the method the container (1) is supported from the outside both on filling and compressing of the storage material (2) and on subsequently charging the material (2) with hydrogen. By this means, deformations of the container wall through expansion of the storage mass or its introduction into the container are inhibited, and the use of larger more economic containers is made possible.

Abstract: A method of and a device for blast heating is described, employing separate indirect heat exchangers for combustion air and fuel gas fed to a regenerator and flue gases discharged from the regenerator. The indirect heat exchangers share heat-transfer liquid recirculating in a circuit in which an auxiliary heat exchanger is connected. In the latter exchanger, the temperature of transfer liquid is increased by combustion of partial streams of combustion air and fuel gas branched off downstream of the indirect heat exchangers. The temperature is increased to such a value which preheats the fuel gas to a temperature at which a substitution of fuel gas of a low calorific value, such as waste gas from a blast furnace, for fuel gas of high calorific value, is made possible.

Abstract: This invention relates to method and apparatus used as an addition to any existing heating system--burning any fuel--for heat recovery from stacks and chimneys. It uses a suitable heat exchanger mounted at the apex of such stacks, by virtue of which location no natural draft is lost. The system includes a circulating pump, a thermostat, an expansion bottle, a condensate trough, a cap and dome which jointly serve to act as unloaders to protect the system liquid from being boiled off. Both sensible heat and the latent heats of moisture in the fuel and in the vapor produced as a combustion product, can be scrubbed out. The use is to effect economies and to reduce environmental contamination wherever fuels are fired.

Abstract: A practical and economical heat pump system stacks the evaporator, compressor, condenser, and expander to use heat from household wastewater more efficiently and effectively. A novel wastewater storage tank treats the wastewater to remove particulates while it supplies its warmest water to the evaporator to provide heat to the refrigerant in the heat pump unit. Heated water exiting the condenser is stored in a separate tank, such as an ordinary hot water heater. The system automatically ensures that the wastewater does not freeze in a substantial amount in the evaporator.

Abstract: A system for recovering waste heat from a stream of heated gas is disclosed. The system includes a convection heat transfer chamber, a boiler tank, and a plurality of heat pipes thermally interconnecting the convection heat transfer chamber with the boiler tank. Each of the heat pipes includes an evaporator section which is disposed in heat transfer relation with a stream of heated gas flowing through the convection heat transfer chamber, and a condenser section disposed in heat transfer relation with a volume of water contained within the boiler tank. The boiler tank is provided with a header plate having an array of heat pipe openings through which the heat pipes project. A heat pipe support sleeve is received in each heat pipe opening in sealed engagement with the header plate, with the heat pipes projecting through the support sleeves and thermally interconnecting the convection heat transfer chamber with the boiler tank.

Abstract: A method and apparatus to recover thermal energy from the exhaust air from a paint spray booth for painting of automobile chasses, whereby heat from the relatively warm exhaust air is transferred to the relatively cold supply air to the booth. The outgoing air is mixed with water or other heat-exchange liquid, and the liquid is then separated in a separation-chamber (7) adjacent the ventilation outlet (6) of the booth (5), and is circulated between the chamber and a heat exchanger (2'), through which the supply air flows.

Abstract: A combustion air preheater for heating combustion air with heat energy provided from flue gas includes both a heat pipe type heat exchanger for effecting low temperature heat transfer between the flue gas and the combustion air and a tube-and-shell type heat exchanger for effecting higher temperature heat transfer. The preheater includes a first heat exchanger, having first and second heat transfer compartments with a plurality of heat pipes extending therebetween and a second, connected heat exchanger which includes a plurality of heat tubes supported by tube sheets within a shell. Ducting is provided to direct flue gas over the tubes of the second heat exchanger and then through one of the compartments of the first heat exchanger and additional ducting is provided to direct combustion air through the other compartment of the first heat exchanger and through the tubes of the second heat exchanger.

Abstract: A combined heat exchanging and ventilating unit is disclosed which is designed for roof installation on a building. The unit includes a heat exchange housing (12) with a heat exchange assembly (34) in it which is capable of being slid into or out of an intake portal (32) on the housing (12) so that easy access can be had to the heat exchange assembly (34) from the roof of the building. The heat exchange housing (12) is particularly designed so that a standard updraft ventilator fan (14) may be used to draw exhaust air through the unit.

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: A water tempering system for preheating water comprises a storage tank for tempered water; a water tempering unit containing S-shaped heat exchange tubes positioned in the exhaust flue of a furnace; first conduit means for conveying water from the storage tank to the tempering unit; and second conduit means for conveying water from the tempering unit to either the storage tank or an outlet tube for the water tempering system.

Abstract: Disclosed are apparatuses and methods for transferring heat from a relatively hot stream of solid materials to a relatively cold stream of solid materials. Both streams cascade downward under the force of gravity over a series of heat pipes which are arranged between the streams to transfer heat therebetween. The heat pipes are arranged so they provide countercurrent heat transfer between the two materials streams. The invention is shown applied to a process for recovering hydrocarbons from shale rock.

Abstract: A flue gas heat recovery system comprises an exhaust gas to air heat exchanger, a hot air to water heat exchanger, a fan, a circulating pump, and a control system which senses the temperature of the exiting air from the air heat exchanger and the temperature of the water leaving the water heat exchanger in combination with the thermostatic sensed temperature of the hot water heating system in order to operate the system in a desired manner. The system may also be used for space heating purposes. The control system in conjunction with the air heat exchanger provides a fail safe system which can be used with solid fueled stoves and fireplace inserts as well as furnaces and hot water boilers without danger of water overheating even during electrical power outages.

Abstract: A heat pipe heat exchanger for transferring heat from a high temperature fluid such as, for example, exhaust gas of a boiler, to a low temperature fluid comprises a first flow path (13,14,15,16,17) along which the high temperature fluid flows, a second flow path (18,19,20,21,22) along which the low temperature fluid flows, and a rotor (28) formed by a plurality of heat pipes (8) disposed across the two flow paths with such intervals that the high temperature fluid or the low temperature fluid can pass therebetween and transferring heat from the high temperature fluid to the low temperature fluid, and the rotor (28) has a separating member (9) fixed to the rotor and separating the first flow path (14,15,16) therein from the second flow path (19,20,21) and is rotatable. By this, corrosion, decreased wall thickness and clogging of the heat pipes is prevented from being localized in a particular portion thereof and the maintenance work of the heat exchanger can be facilitated.

Abstract: An improved high performance ventilation system for application with relatively small temperature-controlled structures for recovering a high percentage of sensible and latent thermal energy from the exhausted air for return via the fresh air stream. Two matrices of thermally absorbent, expanded honeycomb material are alternately interconnected with fan driven supply and exhaust paths via a valve device to store energy in one matrix while retrieving it from the other. The matrices, valve and fans are contained within a single compact highly portable housing which can be installed on the floor, beneath the ceiling and on the roof of the intended structure. Constant air flow direction is maintained in the ventilated area. The valve may be thermostat controlled. The housing is manufactured with a modular design allowing final on-site assembly in a number of varying configurations.

Abstract: A heat scavenger or heat recovery system is provided for use with a furnace such as a hot air furnace, wherein the incoming air to the furnace is preheated, and wherein the exhaust or waste heat that is ordinarily lost up the chimney is recovered and used for preheating the incoming air for the furnace to be used in a home or other building.

Abstract: A heat exchanger in combination with two duct system for bringing in relatively cold outside air into an enclosure while exhausting relatively warm room air from the enclosure. The heat exchanger is positioned so as to recover heat from the exhaust air into the incoming cold fresh air. A valving system switches the incoming cold air with the warm exhaust air in the flow paths of the heat exchanger. This solves the problem of moisture from the exhaust air condensing on the walls of the ducting system for the exhaust air.

Abstract: An earth/block air preconditioner for use in dwellings and other buildings wherein the outside air is drawn below ground and passed through concrete blocks which are preformed with a pair of openings so that the outside air and inside air from the building are in close proximity so as to heat the outside air during the winter time due to the heat exchange arrangement with the inside air before passing it into the building and to cool the outside air during the summer time before passing it into the building. Modern buildings are insulated so tightly that forced ventilation is desirable and the present invention provides highly efficient heating and cooling or ventilation modes for a heat exchange system.

Abstract: A first heat exchanger loop incorporates a thermostatically controlled circulating pump which draws hot water from the heater. Spa water is circulated by the spa pump through a second heat exchange loop surrounding the first. The thermostat sensor detects spa temperature when the spa pump is on and detects heater temperature, and therefore automatically shuts off the circulating pump, when the spa pump is off.

Abstract: A heat recovery unit is adapted for installing in a cookery cupboard or the like space in a dwelling. Within a casing (3) the unit has a lamella heat exchanger (1), which is arranged on one corner edge and has two of its defining surfaces provided with openings for passages facing upwards and two downwards. The heat exchanger has its end walls (8) oriented in vertical planes. It is adapted for heating supply air (9, 10) through heat take-up from exhaust air (11, 12). Four vertical wall portions (13, 16) form a cross above the heat exchanger, thus providing four chambers for the ingoing and outgoing air flows (9-12). By means of portions airtightly sealed against the casing (3) and wall portions (13-17) the heat exchanger is divided into two portions, each having a cross-stream course between supply air (9, 10) and exhaust air (11, 12), with its passages for supply air and exhaust air arranged in series with the corresponding passages of the other portion.

Abstract: An apparatus for recovering waste heat from a hot exhaust pipe and utilizing the heat to warm water passing through the apparatus, which comprises a plurality of thermal conduction members each longitudinally positioned in contact with said exhaust pipe, the plurality of conduction members being arranged circumferentially about the exhaust pipe, each of the thermal conduction members having a surface which is concavely arcuate in cross-section and of substantially the same curvature as that of the exhaust pipe and in contact engagement therewith.The thermal conduction members each have a longitudinal channel with a bottom of arcuate cross-section and a pair of spaced-apart longitudinally extending fins.A water pipe is positioned in the bottom of the channel of substantially the same arcuate cross-section as the bottom surface of the channel. The fins are bent or crimped over the pipe and placed in contact engagement with surface of the pipe.

Abstract: An automatic flue gas heat recovery system for supplementing or replacing a conventional, separate hot water system. In the example described, the heat recovery system is applied to a pizza restaurant where large quantities of heat energy are normally wasted up an oven chimney stack, and large quantities of hot water also are required for restaurant operations. An electric motor driven pump circulates water in a closed loop between a storage tank and a heat exchanger tube located in the oven chimney stack. A thermostat control automatically starts the pump when the oven heats the chimney stack to an effective water heating temperature. When temperature in the storage tank reaches a predetermined maximum, the thermostat control stops the pump, opens a drain valve, and dumps water quickly and completely from the heat exchanger tube. Three different embodiments are shown and described illustrating systems with one or more storage tanks and one or more pumps.

Abstract: Waste water of above ambient temperature in a commercial laundry is directed through a self-cleaning plate and frame heat exchanger to heat incoming fresh water. Some of the fresh water heated to a first temperature is directed to a cold water storage tank to raise the water therein above ambient temperature which results in substantially lessened downstream requirements for heat input with commensurate cost reductions. The remainder of the fresh water is heated to a higher second temperature and is directed to a hot water storage tank. A system of valves regulates the temperature of the water flowing into each of the hot and cold water storage tanks to maintain a preset temperature in each of the storage tanks.

Abstract: A heat exchanger disposed in the piping of the drain line of a shower bath closet for conducting heat from the spent shower bath water to the water entering the cold water inlet of the shower bath. The heat exchanger has at least two concentric helical coils through which the incoming water flows and over which the spent bath water flows. A central core baffle directs the spent water between the helical coils for good transfer of heat. The spent water preheats the incoming cold water thereby reducing the amount of hot water required from the water heater.

Abstract: Furnace structures having smoke and gas return are disclosed. The structures have a closed circuit combustion gas loop and a closed circuit liquid heat transfer loop. The two loops are circulated countercurrent to one another so that maximum heat transfer efficiency is achieved and exhaust emissions are reduced to a minimum.

Abstract: This invention relates to a system for reclaiming or recovering heat which would otherwise be lost from a heating plant. The invention accordingly relates to a heating plant incorporating a plurality of boilers, including a stand-by boiler, there being means for supplying fuel and air to at least one of said boilers, except for the stand-by boiler, and flue gas exhaust ducts associated with each of such boilers. The improvement according to the invention is a waste heat recovery system wherein the flue gas exhaust duct from said at least one boiler is operatively connected to the stand-by boiler for the circulation of hot flue gases therethrough in contact with its heat exchange surfaces thereby to effect the heating of water passing through the stand-by boiler thereby to recover a portion of the heat energy in the flue gases.

Abstract: Method and apparatus for enhancing the heat transfer efficiency and lowering the temperature of tube walls used in a tubular gas to gas heat exchanger. The heat exchanger utilizes essentially flat sided tubes for the transfer of heat from hot gas flowing over the tubes to a cooler gas flowing therethrough. The apparatus of the invention includes a metallic heat shield inserted into the tubes between sides thereof to intercept radiation from the outer walls of said tubes and transfer it to the cooler gas flowing therethrough.

Abstract: A closed-loop heat-transfer system includes in combination an exhaust chamber for positioning in series with a chimney flue of a heating system wherein the exhaust chamber has an exhaust inlet and an exhaust outlet opening adapted for connecting the chamber to the chimney flue. The exhaust chamber includes a first heat exchanger having a fluid inlet opening and a fluid outlet opening and a coiled conduit positioned interior to the chamber interconnecting the fluid inlet and outlet openings. The heat-transfer system also includes a second heat exchanger for positioning in a location remote to the chimney flue, and the second heat exchanger also has a fluid inlet opening and a fluid outlet opening. A conduit couples the fluid openings of the first heat exchanger to the fluid openings of the second heat exchanger to form a closed circulatory loop for a heat-transferring fluid.

Abstract: Waste water heat transfer apparatus (10) is disclosed in which the waste hot water from residential or commercial uses such as washing, etc., is passed into a separate drain (24) and thence into a heat exchanger (17) which includes a waste water conduit (40) therein, and thence to the sewer drain (29). A supply water conduit (70) extends through the heat exchanger (17) generally paralleling the waste water conduit (40) and has fresh water run therethrough in a direction opposite to that of the flow of waste water to an outlet end, after which the supply water is provided to a water heater (20). The heat exchanger interior is filled with a heat transfer liquid (39), and is so divided by baffles (75, 76) that a temperature gradient is formed in the heat transfer liquid adjacent to the waste water conduit (40), with the liquid being warmest adjacent the inlet (68) of the waste water conduit and decreasing in temperature toward the outlet (69) of the conduit.

Abstract: There is disclosed a process and apparatus for the recovery of heat from exhaust or waste gases having a temperature of from about 500.degree. to about 2500.degree. F. generated in a process operation cycling between an operational mode and in idling mode utilizing an intermediate heat transfer fluid to recover heat and to use all or a portion of such recovered heat, inter alia, in such process operation.

Abstract: A heat exchange apparatus is illustrated, which may be used as in a stream of solar heated air for heating flowing water, wherein an array of heat pipes is utilized in heat exchange relation with a manifold, wherein vapor medium is exchanged therebetween for conducting heat from one to the other.

Abstract: Difficulties associated with the operational stability of a conventional cryogenic plant for manufacturing ammonia synthesis gas from a stream rich in hydrogen and a stream of nitrogen are reduced by using three heat exchangers in place of the conventional single heat exchanger. In use, the first heat exchanger, which is preferably arranged with its cold end uppermost, is used to cool the stream of nitrogen to a temperature which:(a) if the nitrogen is above its critical pressure is between 8.degree. and 28.degree. C. above its critical temperature; or(b) if the nitrogen is below its critical pressure is between 3.degree. and 9.degree. C. above its dew point.Part of the nitrogen leaving the first heat exchanger is passed downwardly through a third heat exchanger where it is further cooled before being introduced into a nitrogen wash column where it acts as reflux. The third heat exchanger is cooled by vapor leaving the top of the nitrogen wash column.

Abstract: A ventilation system for a livestock house includes a heat exchanger through which both warm moist air from the interior living area of the house and fresh make-up air from the outside are passed, so that heat will transfer from the former to the latter. Prior to entering the heat exchanger, the warm moist air passes through a filter device that removes particulates from it, so that the particulates do not combine with condensation in the heat exchanger to block the heat exchanger. The fresh air, after being warmed in the heat exchanger passes into an elongated distribution plenum located slightly below the ceiling of the house, and this plenum contains apertures which direct the fresh air horizontally into the living area. Moreover, the upper surface of the plenum is located directly below an elongated opening in the ceiling.

Abstract: An apparatus for recovering energy that can be incorporated in the flue gas discharge duct of a gas or oil fired heating installation which uses a liquid circuit to transfer heat. The apparatus is comprised of supply and discharge connections for the flue gas, a heat exchanger to be incorporated in the liquid circuit, a condensate collection and discharge device, and a fan to force the flue gas flow past the heat exchanger.

Abstract: An improved high performance ventilation system for application with relatively small temperature-controlled structures for recovering a high percentage of sensible and latent thermal energy from the exhausted air for return via the fresh air stream. Two matrices of thermally absorbent, expanded honeycomb material are alternately interconnected with fan driven supply and exhaust paths via a valve device to store energy in one matrix while retrieving it from the other. The matrices, valve and fans are contained within a single compact highly portable housing which can be installed on the floor, beneath the ceiling and on the roof of the intended structure. Constant air flow direction is maintained in the ventilated area. The valve may be thermostat controlled. The housing is manufactured with a modular design allowing final on-site assembly in a number of varying configurations.