US3863708A - Modulatable heat exchanger with restraint to avoid condensation - Google Patents

Modulatable heat exchanger with restraint to avoid condensation Download PDF

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Publication number
US3863708A
US3863708A US431121A US43112174A US3863708A US 3863708 A US3863708 A US 3863708A US 431121 A US431121 A US 431121A US 43112174 A US43112174 A US 43112174A US 3863708 A US3863708 A US 3863708A
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Prior art keywords
air
temperature
heat exchanger
flue gas
flow
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US431121A
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English (en)
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George R Grimes
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Cyprus Amax Minerals Co
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Amax Inc
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Priority to US431121A priority Critical patent/US3863708A/en
Priority to CA212,281A priority patent/CA995659A/en
Priority to GB4803074A priority patent/GB1441552A/en
Priority to FR7437859A priority patent/FR2257070B1/fr
Priority to BE150678A priority patent/BE822387A/xx
Priority to LU71326A priority patent/LU71326A1/xx
Priority to DE2455585A priority patent/DE2455585C3/de
Priority to NLAANVRAGE7415431,A priority patent/NL185228C/xx
Priority to JP49135960A priority patent/JPS5756000B2/ja
Application granted granted Critical
Publication of US3863708A publication Critical patent/US3863708A/en
Anticipated expiration legal-status Critical
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D51/00—Auxiliary pretreatment of gases or vapours to be cleaned
    • B01D51/10—Conditioning the gas to be cleaned
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
    • F28D7/10—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged one within the other, e.g. concentrically
    • F28D7/106—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged one within the other, e.g. concentrically consisting of two coaxial conduits or modules of two coaxial conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F27/00—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2270/00—Thermal insulation; Thermal decoupling

Definitions

  • a heat exchanger system capable of being modulated re qe i ejyt dust-E n flu gas in n elevated dew point
  • a heat exchanger formed of a vertical cylindrical shell containing a bank of tubes vertically disposed therein coupled to tube manifolds at opposite ends thereof such that the bank of tubes communicates with a hot gas inlet and a hot gas outlet coupled respectively to said manifolds each of said tubes being surrounded by a tube to provide annular spaces having manifolds communicating therewith through which air is circulated in said heat exchanger in concurrent flow with said hot flue gas
  • means being provided for maintaining a flow of hot flue gas through said heat exchanger to a downstream line, including a closed circuit air line with a blower for maintaining a flow of air through said heat exchanger in concurrent flow and heat exchanging relationship with said hot flu
  • This invention relates to a heat exchange system and method for cooling hot dust-laden flue gases having an elevated dew point, while inhibiting condensation of moisture on heat exchanger surfaces.
  • molybdenum sulfide roasters are operated in a manner to assure substantially constant temperatures in the hearth atmosphere.
  • the flue gas emanating from the roaster is dust-laden and fairly hot.
  • the flow rate of the flue gas varies with the operation.
  • the flue gas temperature is nominally 400C (752F)
  • the flue flow rate varies between 43,000 and 81,000pounds per hour, depending on the production level and operation, and may contain as much as of the roaster input as dust, which may be removed by mechanical or electrostatic collectors.
  • cyclones, multiclones or electrostatic precipitators has limitations in that they cannot be operated at the flue gas temperature without fouling.
  • Cooling of the flue gas without admission of cold air reduces the volume and favors subsequent treatment to control sulfur oxide emissions for environmental reasons.
  • a control system is required to regulate the temperature of the flue gas to somewhere between dew point, about 200C (392F), and 260C (500F).
  • One object of the invention is to provide a modulatable heat exchanger system for cooling dust-laden flue gas, such as flue gas from a molybdenum sulfide roaster having an elevated dew point.
  • Another object is to provide a method of cooling dust-laden flue gas using a modulatable heat exchanger system in which the conditions are automatically controlled during the heat exchange cycle to avoid condensation of fluids on heat exchanger surfaces.
  • FIGS. 1 and 2 depict plan and elevation views, respectively, of a pair of series connected heat exchangers which may be employed in carrying out the invention
  • FIG. 3 is a schematic drawing of the flow circuit together with control devices for carrying out the various embodiments of the invention
  • FIG. 4 represents a multipoint temperature recorder chart illustrating heat exchanger operation with respect to flue gas temperature, air temperature and the temperature of the heat exchange surface
  • FIGS. 5 and 6 are temperature recording charts showing the temperature control obtained with thermocouples TO! and TC-Z.
  • a modulatable heat exchanger sys tem for cooling hot dust-laden flue gas having an elevated dew point.
  • the system utilizes a heat exchanger formed of a vertical cylindrical shell containing a bank of tubes vertically disposed therein coupled to tube manifolds at opposite ends thereof such that the bank of tubes communicates with a hot gas inlet and a hot gas outlet coupled to said shell, each of said tubes being surrounded by another tube to provide annular spaces with manifolds communicating therewith through which air is circulated in said heat exchanger in concurrent flow with said hot flue gas.
  • the system has means for maintaining a flow of hot flue gas through said heat exchanger to a downstream line and a closed circuit air line including a blower for maintaining a flow of air through said heat exchanger in concurrent flow and heat exchanging relationship with the hot flue gas.
  • a first valve means is provided for feeding air into said line when needed and a first temperaturesensing means for sensing the temperature of the flue gas downstream of said heat exchanger.
  • a second valve means is provided in the air line operable in accordance with the temperature sensed by the first temperature-sensing means for controlling the flow of the air through said heat exchanger, a second temperature-sensing means being associated with a portion of the heat exchanger in contact with the flue gas for sensing the temperature of the heat exchanger at said portion, the second temperaturesensing means being operably coupled to said first valve means for feeding fresh air to the air line.
  • a pressure-sensing device is provided in the air line coupled to an exit air gas valve for opening said valve to expel air from the line when the pressure rises above a predetermined set pressure, whereby the flow of air through the heat exchanger is independently controlled so as to maintain the average temperature of the heat exchanger at above the dew point of the hot flue gas during the cooling thereof.
  • the circulating air may be heated to preheat the heat exchanger during start-up to avoid condensation of fluids during the start-up period.
  • An advantage of the invention is that by maintaining the heat transfer at above the dew point of the gas, the unit can be constructed of mild steel and the problem of dust collection on a wet surface avoided or greatly inhibited.
  • the flow of colder fluid (air) in the annular space surrounding the heat exchange tube is also preferred in that it assures flow of the air parallel to the flow of the flue gas and also assures a substantially equal mass flow of air for each heat exchange tube.
  • the temperature change for both hot and cold fluids is a function of the relation of the mass flow of each to the combined mass flow of both fluids.
  • Concurrent flow of the two fluids is desirable as otherwise longer heat exchange tubes would be required for countercurrent flow of the two fluids.
  • FIG. 1 being a plan view
  • FIG. 2 a sectional view in elevation of the inner parts of a pair of heat exchanger units connected in tandem.
  • FIGS. 1 and 2 a pair of heat exchanger units 10, A is shown, the A designation indicating the same corresponding elements in the corresponding unit.
  • the two units comprise vertically disposed shells 11, 11A having confined therein a bank of heat exchange tubes 12, 12A which are solidly connected to and between tube sheets or headers 13, 13A, said bank of tubes communicating with manifolds 14 and 14A located adjacent the tube sheets or headers of heat exchanger units 10 and 10A.
  • annular tubes 15, 15A Surrounding each tube are annular tubes 15, 15A which are solidly attached to and between tube sheets or headers 16, 16A, said annular tubes communicating with manifolds 17, 17A adjacent headers 16, 16A.
  • the two units have a converging bottom 18, 18A in the form of an inverted cone connected together by a U-shaped conduit 19.
  • the air manifolds 17, 17A at the lower portion of the units are coupled together via conduit 20.
  • the hot flue gas is drawn into unit 10 through inlet 21 by means of a blower, not shown, the flue gas entering manifold 14 and, hence, heat exchange tubes 12. Concurrently with the flow of flue gas, air is similarly drawn into unit 10 via inlet 22 into manifold 17 and down through the annular spaces surrounding tubes 12.
  • the hot flue gas flows through the tubes into lower manifold 14 and via U-shaped conduit 19 into the bottom of heat exchange unit 10A through lower manifold 14A, tubes 12A, upper manifold 14 and then through flue gas exit 21A downstream of the gas flow.
  • cooling fluid (heated or unheated air) flows concurrently and in parallel with the flue gas through annular tubes 15 into lower manifold 17, via conduit into lower manifold 17A, up through annular tubes 15A into upper manifold 17A and finally through exit 22A.
  • the temperature of the heat exchanger surfaces can be maintained at above the dew point of the flue gas being cooled and condensation of corrosive fluids within heat exchanger tubes 12 and 12A substantially inhibited, if not avoided.
  • a schematic illustrating one embodiment of a system for achieving such a control is shown in FIG. 3 to be discussed later.
  • packed joints 23, 23A are provided to allow for differential expansion of heat exchange tubes 12, 12A and annular tubes 15, 15A.
  • expansion joints 24, 24A are provided to allow for differential expansion between shell 10, 10A and annular tubes 15, 15A.
  • the extremities of heat exchange tubes 12, 12A be insulated, e.g. with insulation 25, 25A.
  • the insulation around the heat exchange tubes within the colder fluid manifolds 17, 17A is provided to eliminate problems associated with heat exchange in cross flow.
  • the colder fluid is heated by contact with the first heat exchange tubes in the flow path.
  • the hotter fluid in these first heat exchange tubes enters the parallel flow section at lower temperature than the hotter fluid in subsequent heat exchange tubes.
  • the colder fluid entering the first annular spaces in the flow path enters the parallel flow section at lower temperature than subsequent annular spaces. It is desirable to have uniform temperature distribution for all heat exchange tubes and substantially equal temperature differentials between the hot and cold fluids for each tube.
  • the shell 11 serves as a base insulation on each unit, and to provide an insulating blanket of air around the annular tubes 15, 15A, otherwise temperature loss through the annular tube wall will result in an uneven temperature distribution between the colder fluid in the various annular spaces.
  • Heat loss from the air circulating system determines the maximum available temperature of the air entering the heat exchanger, when the possibility of adding extraneous heat is neglected.
  • the maximum available air temperature determines the maximum allowable air supply for any stated minimum hot fluid flow.
  • the maximum available air flow determines the maximum heat exchange capacity of the heat exchange unit.
  • the heat exchange units be erected vertically. This avoids the problem of dust settling out on heat transfer surfaces when the velocity of the hot fluid is low.
  • the heat exchanger may be constructed as a single unit or as a group of units connected in series.
  • FIG. 3 shows schematically the manner in which the heat exchanger control system functions, using a closed circuit air circulating line with provisions for feeding fresh air into the line and provisions for bleeding off air in instances where the air pressure in the line exceeds a predetermined value, particularly heated air.
  • a motorized butterfly valve V-2 in the air circulating line is adjusted to control via motor 30, the amount of air flow in the line in response to the downstream flue gas temperature measured by a temperature controller TC-l.
  • the motorized valve may open further to permit greater air flow when the downstream flue gas temperature is above the predetermined set point or turned down to decrease the flow when the downstream flue gas temperature falls below the predetermined set point.
  • the temperature controller well known in the art, has a proportional band and automatic reset which causes the valve (damper) to move to a position to maintain the downstream flue gas temperature at the set point.
  • Temperature controller TC-l operates to move the valve via motor 30 towards its full open or to its full closed position in striving to satisfy the required set point.
  • a second temperature controller TC-2 is provided to sense the temperature of the heat exchange surface in contact with the flue gas as shown at Point 31. Calculations indicate that the sensing point may be advantageously located at the inlet of the first heat exchange unit or alternatively, at the outlet of the last heat exchange unit. These calculations indicate that the lowest heat exchange surface temperature must either be at the inlet ofthe first unit or the outlet of the last unit depending upon the particular mass flow rates and inlet fluid temperatures.
  • the inlet of the first unit is the preferred location of the sensing point for the reason that observations have shown the lowest heat exchange surface temperatures would be at the inlet of the first unit the temperature of the heat exchange surface at the inlet of the first unit is immediately affected by a change in mass flow rates or inlet temperatures, whereas the heat transfer surface temperatures response at the outlet of the last unit 10A is tempered by the heat capacity of the heat exchanger metal.
  • Temperature controller TC-2 controls motorized butterfly valves V-l and V-4 via motors 32 and 33, respectively. These two valves are mechanically linked so that they move in opposite directions, one opening as the other closes and vice versa.
  • the motorized butterfly valve V-l controls the amount of fresh air entering the air circulating system.
  • the motorized butterfly valve V-4 controls the amount of heated air which is recirculated. lf the temperature is below the set point, temperature controller TC-2 moves valves V-l and V-4 in a way to increase the temperature of the air entering the heat exchanger by reducing the amount of fresh air intake and increasing the amount of heated air recirculated.
  • temperature controller TC-2 moves the motorized butterfly valve (damper) V-l via motor 32 toward the open position and the motorized butterfly valve (damper) V-4 toward the closed position. As with the first controller TC-l, temperature controller TC-2 is free to move the valves under its control to their full travel positions in its effort to maintain the heat transfer surface temperature at the set point.
  • the two temperature controllers, TC-l and TC-2 are free to act independently, but with the action of either affecting the temperature element measured and controlled by the other. Under these circumstances, there are conditions under which the action of one controller counteracts the action of the other, only one of the two set points (flue gas outlet temperature and heat transfer surface temperature) can be satisfied.
  • the air handling capacity is engineered so that the maximum air flow at its highest realizable temperature is insufficient to reduce the heat transfer surface below the dew point with the minimum design flue gas flow in the system. This insures that the heat transfer surface temperature restraint is observed in preference to observing the set point for flue gas temperature control.
  • Maximum air flow setting is determined by a predetermined setting of manually operable valve V-S.
  • a pressure controller PC-3 senses the pressure in the air circulating system downstream from the air blower B-2.
  • a motorized butterfly valve V-3 is controlled by the pressure controller PC-3 to which motor 34 is responsive. This valve controls the amount of heated air exhausted from the air circulating system.
  • the pressure controller PC-3 senses an increase in pressure, it causes motorized butterfly valve V-3 to open to discharge heated air from the air circulating system to maintain a constant pressure at the air blower discharge irrespective of the proportions of ambient air and recirculated hot air to be introduced into the heat exchanger.
  • pressure controller PC-3 senses a decrease in pressure, it causes the motorized butterfly valve V-3 to move toward the closed position and reduce the exhaust of heated air from the air circulating system.
  • a temperature indicator Tl-l be provided at point 31A at the end (unit 10A) opposite the location of temperature controller TC-2. Test calculations have found only a few degrees difference in the heat transfer surface temperature at the two ends of the heat exchanger. In the absence of temperature indicator Tl-l, some small elevation of the set point above the dew point of the flue gas will suffice.
  • a system for preheating the heat exchangers by circulating heated air is desirable. This is indicated by the presence of heater H-l shown in the schematic flow and control of FIG. 3.
  • lts function is to heat a suitable quantity of air for circulation in the closed system as a means for preheating the heat exchange tubes prior to introduction of flue gas.
  • Temperature indicators Tl-Z and Tl-3 may be placed in the air line as shown to provide a check on the air temperature. Introduction of flue gas into cold heat exchange tubes could cause some condensation with consequent fouling of the heat transfer surface during start-up. Thus, preheating the tubes prior to start-up may be desirable.
  • a method for modulating the temperature of a heat exchanger in which hot flue gas is passed through a bank of heat exchanger tubes, each of the tubes being surrounded by an annular tube to provide annular spaces through which air is passed in concurrent and heat exchanging relationships with the flow of said flue gas, the flue gas flowing through the heat exchanger to a downstream line for further treatment, the air used for extracting heat from the flue gas being continuously circulated through the heat exchanger via a closed circuit air circulating system.
  • the method in its broad aspects comprises continuously feeding flue gas at variable temperatures and flow rates through the heat exchanger tubes; continuously feeding air (either heated or unheated) concurrently along and around the outside surface of the heat exchange tubes at a variable but not exceeding a predetermined maximum flow rate to effect cooling of said flue gas; continuously sensing the temperature of a portion of said heat exchanger in heat exchange contact with said flue gas with respect to a predetermined set condition; when needed, varying the input of air into said air circulating system via a first valve responsive to the difference of temperature sensed at the heat exchanger portion; continuously sensing the temperature of the flue gas leaving said heat exchanger downstream thereof with respect to a predetermined set condition; varying the flow of air through said heat exchanger via a second valve in the air circuit responsive to the difference in temperature between said flue gas and the set condition; continuously sensing the air pressure in said air circulating system with respect to the predetermined pressure set condition; controlling the pressure in said air line with respect to said set condition via a third valve responsive to the difference in pressure sensed, such
  • control system functions as follows: 7
  • the heat exchanger design and control system comprises:
  • a system capable of handling a variable flow of dust-laden flue gas at variable input temperature with restraint to hold the heat transfer surface temperature above the dew point of the flue gas.
  • a system capable of maintaining constant heat transfer surface temperature irrespective of the flue gas flow rate or temperature (so long as flue gas flow rates and/or temperature are within design limits).
  • a system capable of maximizing heat transfer allowable while observing the heat transfer surface temperature restraint.
  • a system capable of extended length to effect in creased temperature differential through the heat exchanger without changing flow quantities or the ratio of maximum to minimum flow design.
  • a system capable of handling flue gas at input temperatures approaching the dew point of the flue gas, provided that the allowable heat loss is no less than the heat loss from the circulating air system.
  • a system capable of handling flue gas at higher than design temperature, provided the temperature does not exceed the temperature limitations for the materials of construction, and provided that higher downstream flue gas temperatures are permissible.
  • heat balance calculations have covered mass flow rates of flue gas from 5,000 lbs/hr ft to 15,000 lbs/hr ft with input tempera tures from 530F to 750F (278C to 400C) and heat exchange lengths of 40 to feet, assuming the dew point of the flue gas as 400F (205C).
  • the downstream flue gas temperature would be 584F (306C) compared to 538F (281C) for 10,000 lbs/hr ft, when using the same maximum air flow rate.
  • FIGS. 4, 5, 6 and Table 1 data obtained for a particular heat exchanger system of the type of the present invention is illustrated by FIGS. 4, 5, 6 and Table 1.
  • the particular heat exchange unit consisted of two units in series, each 6 meters (19.68 feet) long with X 4.5 millimeter tubes inside 267 X 5 millimeter tubes, with the flue gas flowing through the annular space between the two pipes in accord with the control system described.
  • FIG. 4 is a continuous record of flue gas, air, and heat exchange surface temperatures as monitored by a multipoint recorder during an interval that the flue gas flow rate changed from 7,100 lbs/hr ft at about 360C (680F) to 10,200 lbs/hr ft at about 300C (572F).
  • FIGS. 5 and 6 are a record of the temperature control effected by TC-l and TC-2 of FIG. 3.
  • Table 1 The data of Table l were compiled from a pilot run in which the system was continuously operated for about 3 months. Continuous records were kept and Table 1 represents typical measurements for selected heat transfer surface temperature set points (note last column of Table l) correlated with instantaneous changes in flue gas flow rates and inlet temperature (note the third and fourth columns of the table). In Table 1 below, the set point for the temperature controller (TC-2) was successively changed from 230C to 215C to 210C.
  • a modulatable heat exchanger system for cooling hot dust-laden flue gas having an elevated dew point which comprises,
  • a heat exchanger unit formed of a bank of tubes coupled to tube manifolds such that the bank of tubes communicates with a hot gas inlet and a hot gas outlet coupled respectively to said manifolds, each of said tubes being surrounded by a tube to provide annular spaces having manifolds communicating therewith through which air is circu- 4O lated in said heat exchanger in concurrent flow with said hot flue gas,
  • a closed circuit air line including a blower for maintaining a flow of air through said heat exchanger in concurrent flow and heat exchanging relationship with said hot flue gas
  • first temperature-sensing means for sensing the temperature of the flue gas downstream of said heat exchanger
  • second valve means in said air line operable in accordance with the temperature sensed by said first temperature sensing means for controlling the rate of flow of said air through said heat exchanger according to the temperature sensed by said first temperatures-sensing means
  • second temperature-sensing means associated with a portion of the heat exchanger in contact with said flue gas for sensing the temperature of the heat exchanger at said portion
  • said second temperature-sensing means being op- 65 erably coupled to said first valve means for controlling the feeding of fresh air to said air line,
  • a pressure-sensing device in said air line coupled to a third valve means comprising an exit air gas valve for opening said valve to expel air from said line when a pressure above a predetermined pressure is sensed in the air line,
  • said second temperature-sensing means coupled to said first valve means is also operably coupled to a fourth valve means located in said air line,
  • said fourth valve means being mechanically linked to first valve means
  • the heat exchanger system of claim 1 including a heater coupled to a portion of the air line for preheating the air to a predetermined temperature, said air line portion being connected to said third air valve means for bleeding air from the system when the air pressure increases above the predetermined air pressure set point.
  • a modulatable heat exchanger system for cooling hot dust-laden flue gas having an elevated dew point which comprises,
  • a heat exchanger formed of a vertical cylindrical shell containing a bank of tubes vertically disposed therein coupled to tube manifolds at opposite ends thereof such that the bank of tubes communicates with a hot gas inlet and a hot gas outlet coupled respectively to said manifolds, each of said tubes being surrounded by a tube to provide annular spaces having manifolds communicating therewith through which air is circulated in said heat exchanger in concurrent flow with said hot flue gas,
  • a closed circuit air line including a blower for maintaining a flow of air through said heat exchanger in concurrent flow and heat exchanging relationship with said hot flue gas
  • first valve means for feeding fresh air into said air line when needed and another valve means in said air line mechanically linked with said first valve means, such that when the first valve means opens, said other valve means closes and when said first valve means is caused to move to the closed position, the mechanically linked valve is caused to move towards the open position,
  • first temperature-sensing means for sensing the temperature of the flue gas downstream of said heat exchanger
  • second valve means in said air line operable in accordance with the temperature sensed by said first temperature-sensing means for controlling the rate of flow of said air through said heat exchanger according to the temperature sensed by said first temperature-sensing means
  • second temperature-sensing means associated with a portion of the heat exchanger in contact with said flue gas for sensing the temperature of the heat exchanger at said portion, said second temperature-sensing means being operably coupled to said first valve means for controlling the feeding of fresh air to said air line and for controlling the flow of air through said valve means mechanically linked to said first valve means,
  • a manually operable valve means in said air circuit to provide a fixed maximum air flow setting to said air line
  • a heater coupled to a portion of said air line for preheating the air to a predetermined temperature
  • a pressure-sensing device in said air line coupled to a third valve means comprising an exit air gas valve for opening said valve to expel heated air from said line when a pressure above a predetermined pressure is sensed in said line,
  • the temperature of the heat exchanger is maintained at a predetermined temperature above the dew point of the flue gas during the cooling thereof.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Air Supply (AREA)
US431121A 1974-01-07 1974-01-07 Modulatable heat exchanger with restraint to avoid condensation Expired - Lifetime US3863708A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US431121A US3863708A (en) 1974-01-07 1974-01-07 Modulatable heat exchanger with restraint to avoid condensation
CA212,281A CA995659A (en) 1974-01-07 1974-10-25 Modulatable heat exchanger with restraint to avoid condensation
GB4803074A GB1441552A (en) 1974-01-07 1974-11-06 Heat exchange system for cooling hot dust-laden gases
FR7437859A FR2257070B1 (enrdf_load_stackoverflow) 1974-01-07 1974-11-18
BE150678A BE822387A (fr) 1974-01-07 1974-11-19 Echangeur de chaleur a modulation pour refroidissement de gaz brules
LU71326A LU71326A1 (enrdf_load_stackoverflow) 1974-01-07 1974-11-21
DE2455585A DE2455585C3 (de) 1974-01-07 1974-11-23 Verfahren zum Abkühlen von heifieminsbesondere staubbeladenem-Rauchgas in einem Wärmeaustauscher und Vorrichtung zum Durchführen des Verfahrens
NLAANVRAGE7415431,A NL185228C (nl) 1974-01-07 1974-11-26 Werkwijze voor het afkoelen van heet met stof beladen rookgas in een warmtewisselaar.
JP49135960A JPS5756000B2 (enrdf_load_stackoverflow) 1974-01-07 1974-11-28

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US431121A US3863708A (en) 1974-01-07 1974-01-07 Modulatable heat exchanger with restraint to avoid condensation

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US (1) US3863708A (enrdf_load_stackoverflow)
JP (1) JPS5756000B2 (enrdf_load_stackoverflow)
BE (1) BE822387A (enrdf_load_stackoverflow)
CA (1) CA995659A (enrdf_load_stackoverflow)
DE (1) DE2455585C3 (enrdf_load_stackoverflow)
FR (1) FR2257070B1 (enrdf_load_stackoverflow)
GB (1) GB1441552A (enrdf_load_stackoverflow)
LU (1) LU71326A1 (enrdf_load_stackoverflow)
NL (1) NL185228C (enrdf_load_stackoverflow)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4042011A (en) * 1975-12-22 1977-08-16 Phillips Petroleum Company Refrigeration control
FR2494424A1 (fr) * 1980-11-17 1982-05-21 Snow Brand Milk Products Co Ltd Dispositif de recuperation des chaleurs perdues pour empecher la corrosion par les oxydes de soufre
US6334483B1 (en) * 1996-10-14 2002-01-01 Edmeston Ab Support plate for tube heat exchangers and a tube heat exchanger
EP1139055A3 (de) * 2000-03-29 2002-01-16 SGL Acotec GmbH Mehrfachrohrbündel-Wärmeaustauscher
CN102345988A (zh) * 2010-08-06 2012-02-08 詹其国 一种新型的煤气风冷塔
US20130247845A1 (en) * 2010-12-27 2013-09-26 Mitsubishi Heavy Industries, Ltd. Heat recovery and utilization system
US20140096936A1 (en) * 2012-10-02 2014-04-10 Behr Gmbh & Co. Kg Heat exchanger
US10184690B2 (en) * 2017-02-09 2019-01-22 Bock Water Heaters, Inc. Condensing water heater and condensation control system
CN109443052A (zh) * 2018-10-24 2019-03-08 中国科学院理化技术研究所 一种液态金属高温换热器和换热系统
CN114593522A (zh) * 2020-07-23 2022-06-07 中北大学 一种烟温测量协同控制热管系统

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US4693233A (en) * 1986-04-03 1987-09-15 Energy Technology, Inc. Air preheater system
CN107388852B (zh) * 2017-07-26 2018-12-14 西安交通大学 一种气气高温换热器

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US3310365A (en) * 1962-10-30 1967-03-21 Southern California Edison Co Flue gas process
US3820590A (en) * 1973-02-28 1974-06-28 B Littman On-line adaptive control of a heat exchanger

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Cited By (14)

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Publication number Priority date Publication date Assignee Title
US4042011A (en) * 1975-12-22 1977-08-16 Phillips Petroleum Company Refrigeration control
FR2494424A1 (fr) * 1980-11-17 1982-05-21 Snow Brand Milk Products Co Ltd Dispositif de recuperation des chaleurs perdues pour empecher la corrosion par les oxydes de soufre
US6334483B1 (en) * 1996-10-14 2002-01-01 Edmeston Ab Support plate for tube heat exchangers and a tube heat exchanger
EP1139055A3 (de) * 2000-03-29 2002-01-16 SGL Acotec GmbH Mehrfachrohrbündel-Wärmeaustauscher
CN102345988A (zh) * 2010-08-06 2012-02-08 詹其国 一种新型的煤气风冷塔
US9803853B2 (en) * 2010-12-27 2017-10-31 Mitsubishi Hitachi Powers Systems, Ltd. Heat recovery and utilization system
US20130247845A1 (en) * 2010-12-27 2013-09-26 Mitsubishi Heavy Industries, Ltd. Heat recovery and utilization system
US20140096936A1 (en) * 2012-10-02 2014-04-10 Behr Gmbh & Co. Kg Heat exchanger
US9709343B2 (en) * 2012-10-02 2017-07-18 Mahle International Gmbh Heat exchanger
US9709344B2 (en) * 2012-10-02 2017-07-18 Mahle International Gmbh Heat exchanger
US20140096937A1 (en) * 2012-10-02 2014-04-10 Behr Gmbh & Co. Kg Heat exchanger
US10184690B2 (en) * 2017-02-09 2019-01-22 Bock Water Heaters, Inc. Condensing water heater and condensation control system
CN109443052A (zh) * 2018-10-24 2019-03-08 中国科学院理化技术研究所 一种液态金属高温换热器和换热系统
CN114593522A (zh) * 2020-07-23 2022-06-07 中北大学 一种烟温测量协同控制热管系统

Also Published As

Publication number Publication date
DE2455585B2 (de) 1979-07-19
NL7415431A (nl) 1975-07-09
FR2257070A1 (enrdf_load_stackoverflow) 1975-08-01
FR2257070B1 (enrdf_load_stackoverflow) 1978-06-16
DE2455585C3 (de) 1980-03-20
NL185228B (nl) 1989-09-18
BE822387A (fr) 1975-03-14
GB1441552A (en) 1976-07-07
CA995659A (en) 1976-08-24
LU71326A1 (enrdf_load_stackoverflow) 1975-05-28
DE2455585A1 (de) 1975-07-10
NL185228C (nl) 1990-02-16
JPS50101950A (enrdf_load_stackoverflow) 1975-08-12
JPS5756000B2 (enrdf_load_stackoverflow) 1982-11-27

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