US3148516A

US3148516A - Air cooled vacuum producing condenser

Info

Publication number: US3148516A
Application number: US252748A
Authority: US
Inventors: Kals Walter
Original assignee: Niagara Blower Co
Current assignee: Niagara Blower Co
Priority date: 1963-01-21
Filing date: 1963-01-21
Publication date: 1964-09-15
Anticipated expiration: 1981-09-15

Description

Sept. 15, 1964 w. KALS 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 3 Sheets-Sheet 1 e9 68. 1 g)- ANOOQOOOOOOO w INVENTOR.

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Sept. 15, 1964 w, A 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 I 3 Sheets-Sheet 2 w M INVENTOR.

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Sept. 15, 1964 w, Ls 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 3 Sheets-Sheet C5 INVENTOR s? z gj z:

grog/m6 United States Patent Oflice 3,143,516 A {IOOLED VACUUM PRODUCING CONDENSER Waiter Kals, Hastings on Hudson, N.Y., assignor to Niagara Blower Company, New York, N.Y., a corporation of New York Filed Jan. 21, 1963, Ser. No. 252,748 12 Qlaims. (Cl. 62-3t35) This invention relates to an air cooled vacuum producing condenser and more particularly to such a condenser of the evaporative type in which the cooling effect is obtained principally from the evaporation of water on the exterior of the tubes of the main condenser and intercondenser which are arranged in an air stream passing over these tubes.

This invention is an improvement on the condenser shown and described in my Patent 2,570,247 dated Octoher 9, 1951.

In common with said patent, an object is to provide a large capacity steam or vapor condenser cooled by the evaporation of water on the external surfaces of wetted tubes, such an evaporative condenser having many times the capacity of a dry coil of the same size and being economical in the use of cooling water in that the water is evaporated to use the latent heat of the water in providing the cooling effect.

Another object in common with said patent is to provide a vacuum producing condenser in which the removal of air or non-condensible gases from the vapor being handled is effected under conditions most favorable to the operation of a steam jet air ejector in ejecting the maximum amount of air from the system with the minimum consumption of steam,

Another object in common with said patent is to provide such a vacuum producing condenser in which the cooling eifect is increased or decreased in response to changes in the load on the condenser and in which the tubes are arranged and proportioned to provide a balanced system with a minimum of cooling surface.

A specific object of the present invention is to increase the devaporization of the air-vapor mixture leaving the main and intercondenser tubes and before being admitted to the corresponding first and second stage steam ejectors, this being achieved by improved removal of entrained water in the headers through which the air-vapor mixture passes and by cooling the devaporization or subcooling tubes to a lower temperature this being achieved by arranging these tubes to be served by direct fresh air and recirculated water in contradistinction to being served by air previously passed over the wetted main condensing tubes, as in said patent.

Another specific object is to provide such a vacuum producing condenser in which the main condenser, intercondenser and aftercondenser are served by separate streams of air and in which all streams are produced by the same fan means and in a compact casing, the present condenser being characterized by down flow of the streams of air separately through the main condenser, intercondenser and aftercondenser into the bottom of a central plenum chamber from which the air is discharged upwardly.

Another specific object is to provide a reflux or drain linefor conduction condensate from a lower to a higher pressure header but otherwise isolating these headers from each other, this being achieved by providing a vertical leg in the reflux or drain line of such height as to maintain a column of liquid therein of a height proportional to the pressure differential between the two headers.

Another specific object is to provide concurrent flow of the air and water sprays so that one does not impede the flow of the other.

Patented Sept. 15, 1964 Another specific object is to increase the efiiciency of the spray water system, this being achieved by segregating the lower temperature water serving the main condenser from the higher temperature water serving the intercondenser.

Other objects and advantages of the invention will be apparent from the following description and drawings in which:

FIG. 1 is a simplified front elevational view of a vacuum producing condenser embodying the present invention.

FIG. 2 is a simplified vertical transverse section therethrough looking toward the front thereof.

FIG. 3 is a simplified vertical longitudinal section taken through the main condenser section generally on lines 3-3, FIG. 1.

FIG. 4 is a simplified vertical longitudinal section taken through the intercondenser section generally on line 4-4, FIG. 1.

FIG. 5 is a simplified vertical longitudinal section through the aftercondenser section taken generally on line 55, FIG. 1.

The Shell The vacuum producing condenser of the present invention is shown as including a main sheet metal shell iii the bottom or base of which includes a rectangular sump 11 extending centrally fore-and-aft the full length of the sheil, and rectangular inclined bottom drain panels 12, 13 serving to lead any falling water in the shell to the sump. The shell iii includes

vertical side walls

14, 15 rising from those edges of the drain panels 12, 13 remote from the sump 11, and front and

rear walls

16, 1 8 connecting with the front and rear edges of the sump 11, drain panels 12, 13 and

side walls

14, 15. The front and rear walls have central rectangular upward extensions i9, 26, respectively, forming the front and rear walls of a plenum'chamber 21, the side walls of which plenum chamher are formed by

panels

22, 23 which extend downwardly etween the front and

rear walls

16, 18 toward the sump 11.

The space bounded by the plenum chamber panel 22 and the front, rear and side walls 16, it; and T4, of the shell is open at its top and bottom and forms a main condenser chamber 25. The space bounded by the plenum chamber panel 23 and the front, rear and

side panels

16, 18 and 15, contains a vertical partition 26 bridging this space between the front and rear walls and forming with the plenum chamber panel 23 an intercondenser chamber 28, which. is open at its top and bottom. This vertical partition 26 forms with the side wall 15 an aftercondenser chamber 29 which is open at its top and bottom.

Air Flow Movement of outside air through the shell is effected by fans 3% which are of the airplane propeller type and each driven by an electric motor 31. Each motor 311 can be mounted in any suitable manner as by a. support 32 bridging between the plenum

chamber side planels

22 and 23. The propellers 30 rotate to move the air upwardly and out through the open top of the plenum chamber 21.

Accordingly, one stream of outside air is drawn downwardly through the main condenser chamber 25 through the open top thereof into the bottom of the shell and thence upwardly through the plenum chamber 21 to be discharged through the open top thereof. A second stream of outside air is drawn downwardly through the intercondenser chamber 28 through the open top thereof into the bottom of the shell and thence upwardly through the plenum chamber 21- to be discharged through the open top thereof. A third stream of outside air is drawn downwardly through the aftercondenser chamber 2@ through the open top thereof into the bottom of the shell and thence upwardly through the plenum chamber 21 to be discharged through the open top thereof.

Main Condenser Openings

35 and 36 are provided in the portions of the front and

rear walls

16, 18 forming the main condenser chamber and to the margin of the opening is secured a tube sheet 37 forming part of a main condenser 38 and to this tube sheet is secured both a steam or vapor inlet header 39 and a non-condensible or air outlet header 40, the latter being arranged above the steam or vapor inlet header 39. The steam or vapor to be condensed is admitted to the steam or vapor header 39 through an inlet 42 and thence passes through a series of main condenser tubes 43 across the main condenser chamber 25, the opposite ends of which connect with the tube sheet 44 of a condensate header 45. This condensate header encloses the opening 36 and is divided into a condensate outlet chamber 46 and an air-vapor chamber 48 by an internal horizontal partition 49 above the tubes 43 and extended partway across the interior of the header and by a screen 50 extending downwardly from the outboard raised edge of this partition 49 to the lower part of the header 45 and with the partition 49 isolates the chamber 46 from the chamber 48 so that steam or vapor and air entering the chamber 48 is required to pass through the screen 50. The horizontal partition 49 is provided with weep holes w. This screen is preferably made of matted or intertwined metal strands so as to remove any entrained water from the passing mixture of vapor and air. This removed water, together with the condensate formed on passing through the main condenser tubes 43, flows out through an outlet 51 which at the bottom of the header 45 can connect with a hot well (not shown).

A bundle of air devaporizing or subcooling tubes 55 extend from the tube sheet 44 above the partition 49 to that portion of the sheet 37 enclosed by the air outlet header 40. This air outlet header 40 is divided into a condensate collecting chamber 58 and an air-vapor chamber 59 by a screen 60 which insolates these chambers from each other so that the mixture of air and vapor is required to pass through the screen, this screen also being in the form of intertwined or matted metal strands so as to remove any entrained liquid from the mixture of air and vapor passing therethrough.

An important feature of the invention resides in the inclusion of a small number of reflux drain tubes 61 between the

headers

40 and 45 and returning any condensate from the bottom of the condensate collecting chamber 58 of the air outlet header 40 to the condensate outlet chamber 46, these reflux or drain tubes 61 each having a vertical leg 62 of sufficient length to maintain a column of liquid 63 therein, the height of this column of liquid 63 being determined by the pressure drop across the air devaporizing or subcooling tubes 55 and through the screen 50. This column 63 of liquid siphons the condensate from the condensate collecting chamber 58, where a lower pressure prevails, to the condensate outlet chamber 46 where the pressure is slightly higher.

Any condensate accumulating on top of the horizontal shelf or partition 49 will pass through the weep holes w provided in that partition 49 and will thus be guided into the condensate outlet chamber 46.

The air-vapor mixture outlet connection 65 from the air outlet header 40 connects via a pipe 66 with a steam jet air ejector 68 which is supplied with steam from a steam line 69 and which forms a first stage jet air ejector. The steam jet air ejector 68 discharges, at an intermediate vacuum, into an outlet line 70.

lntercondenser This line 70 discharges into the inlet 42a of an intercondenser 38a in the intercondenser chamber 28. Except for size the construction of this intercondenser 38a is identical with the main condenser 38 and a detailed description is not repeated, corresponding parts being distinguished by the suffix a, and the tube sheets 37a and 44a of the intercondenser being secured across

openings

35a and 36a formed in those portions of the front and

rear walls

16, 18 forming the intercondenser chamber 28. The steam air ejector 68:: from the intercondenser 38a, and which forms a second stage steam jet air ejector, discharges into a line 71 leading to an aftercondenser indicated generally at 72.

A ftercondenser This aftercondenser 72 is arranged across the aftercondenser chamber 29 and comprises an inlet header 75 across an opening 67 in that portion of the front wall 16 forming the upper part of the aftercondenser chamber 29. The line 71 connects with this inlet header 75, and a series of serpentine tubes 76 filling the aftercondenser chamber 29 connect this inlet header 75 with an outlet header '78. These tubes 76 are preferably provided with an extended surface in the form of parallel spaced plates 77 secured thereto, these plates serving to improve the heat transfer from the tubes to the passing outside air. The outlet header 78 is arranged to close an opening 79 in that portion of the front wall 16 forming the lower part of the aftercondenser chamber 29 and is provided with an outlet nipple 80 leading to the atmosphere with a downward drain 81 and an upward vent 82.

Main Condenser Spray Water System The main condenser 38 is cooled by a captive body of water 85 which is continuously revolved over the external surfaces of the condensing tubes 43 and air devaporizing or subcooling tubes 55. The heat being so received by this body of water is steadily surrendered to the stream of air moving through the main condenser chamber 25, the wet tubes and the falling water between them providing the necessary contact surface for the transmission of heat and water vapor from the captive body of water to the stream of coolant air. The mass transfer of water to air occurs by evaporation and the heat surrendered by the body of water 85 to the air is therefore predominantly latent.

The body of water 85 is contained in the sump 11, separated from another body of water 86 contained in the sump by a partition 88. Each ofthese bodies of water can be supplied with make-up water in any suitable manner (not shown), and the body of water 85 is withdrawn by a pump 89 which discharges into a line 90 connected with a spray tree 91 in the main condenser chamber 25 above the air devaporizing or subcooling tubes 55 of the main condenser 38. This spray tree includes a multiplicity of nozzles 92 directing sprays of water 93 downwardly over all portions of the

tubes

55, 61 and 43 of the main condenser 38, this water evaporating to use the latent heat of the water in providing the cooling effect for these tubes. The excess water from these tubes falls onto the inclined drain panel 12 from which it returns to the body of water 85 in the sump 11.

lntercona'enser Spray Water System The intercondenser 38a is cooled in exactly the same manner as the main condenser 38, its tubes being wetted by recirculated spray water supplied from the body of water 86 in the sump 11 by means of a pump 95. This pump discharges into a line 96 connected with a spray tree 98 in the intercondenser chamber 28 above the air devaporizing or subcooling tubes 55a of the intercondenser 33a. The spray tree includes a multiplicity of nozzles 99 directing sprays of water 100 downwardly over all portions of the

tubes

55a, 61a and 43a of the intercondenser 38a, a portion of this water evaporating to use the latent heat of the water in providing the cooling effect for these tubes.

The excess water from these tubes fall into a trough 191 the ends of which can be closed by the front and

rear walls

16, 18 of the casing and one longitudinal edge of which can be secured to the lower edge of the vertical partition 26 which for this purpose preferably extends below the intercondenser chamber 28 and the aftercondenser chamber 29 which it separates. The spray water collecting in the trough 101 escapes through an outlet or drain pipe 102 which returns the spray water to the body of water 86 contained with the sump 11.

Operation It is assumed that the fans 30 are operating to move the air in the plenum chamber 21 upwardly, this causing three streams of atmospheric air to move downwardly past the tubes of the main condenser 38, intercondenser 38a, and aft'ercondenser 72, respectively. Thus one of the streams of outside air is drawn downwardly through the main condenser chamber 25 through the open top thereof into the bottom of the shell 11] and thence upwardly through the plenum chamber 21 to be discharged through the open top thereof. A second stream of outside air is drawn downwardly through intercondenser chamber 28 through the open top thereof into the bottom of the shell and thence upwardly through the plenum chamber 21 to be discharged through the open top thereof. A third stream of outside air is drawn downwardly through the aftercondenser chamber 29 through the open top thereof into the bottom of the shell and thence upwardly through the plenum chamber 21 to be discharged through the open top thereof.

It will also be assumed that the spray water pump 89 is in operation to withdraw spray water from the body 85 and discharge it in the form of downwardly directed sprays 93 from the spray tree 91 against the tubes of the main condenser 38 to wet these tubes and evaporate thereon, the excess spray water falling on its inclined drain panel 12 and being returned to the body of water 85.

It will also be assumed that the spray water pump 95 is in operation to withdraw water from the body 86 in the sump 11 and to discharge it in the form ofdownwardly directed sprays 194 from the spray tree $8 over the tubes of the intercondenser 38a to wet these tubes and evaporate thereon. The excess Water from these tubes falls into the trough 101 and is returned by the drain line 1112 to the body of water 86.

It will also be assumed that the steam or vapor to be condensed is supplied to the inlet 42 of the main condenser 38 and that the

condensate outlets

51 and 51a of the main condenser 33 and the intercondenser 38a, respectively, are connected to a hot well to maintain a vacuum in the

condensate headers

45 and 45a.

It will also be assumed, as an example of operation,

, that the outside air is at 90 dry bulb and 75 wet bulb temperature.

The vapor or steam to be condensed enters the inlet header 3% of the main condenser 38 at 42 and passes through the main condenser tubes 43 in which condensation takes place, the condensate entering the condensate outlet chamber 46 of the condensate header 45 and the condensate flowing out at 51 into the hot well (not shown) which maintains a vacuum in the condensate header 45. Assuming that the condensing pressure in the main condensing tubes 43 to be 2" Hg absolute and the condensing temperature to be 101 F, the temperature of the spray water in the body 85 in the sump 11 would be in the order of 89 F., this recirculating water wetting the tubes 43 and evaporating thereon to provide the principal cooling effect in condensing the vapor passing therethrough.

The vapor or steam, however, contains a very considerable quantity of air as a non-condesible gas, this air being admitted in solution with the boiler feed water and also entering through leakage into the system maintained under vacuum by the present vacuum producing condenser. This air mixes with the steam or vapor in any proportion if the steam is at the saturation temperature corresponding to the prevailing pressure.

The

steam air ejectors

63, 68a perform best when handling an air-vapor mixture containing the least amount of vapor. This is because the air ejectors handle a certain weight of gaseous fluid and hence the portion of vapor in the air-vapor mixture greatly reduces the air removal capacity of the air ejectors.

Accordingly the air-vapor mixture from the condensate outlet chamber 46 in the condensate header 45 is required to pass through the screen 511 of matted metal strands so that any entrained liquid is removed therefrom.

The resulting air-vapor mixture entering the air-vapor chamber 48 leaves through the air devaporizing or subcooling tubes 55 above the main condensing tubes 43 and through which the air-vapor mixture from the main condensing tubes passes before reaching the first stage steam ejector 68.

The important feature of locating the air devaporizing or subcooling tubes 55 above the main condenser 33, causing upwardly moving air to separate and escape from the downward gravity flow of condensate in the condensate outlet chamber 46, this separation being facilitated by the movements in opposite directions, is retained from my previous invention described in my Patent 2,570,247. A feature of the present invention is the cooling of the air devaporizing or subcooling tubes 55 by a stream of air taken directly from the outdoors at lowest available wet bulb temperature (lowest enthalpy). The cooling effect to which these air devaporizing or subcooling tubes 55 are thus subjected is greater than if these tubes were downstream from the main condenser tube 43 with reference to the air stream.

The cooling elfect to any portion of the sprayed, wet heat transfer surface is in direct proportion to the difference between the enthalpy of an air film saturated with water vapor at the spray contact temperature and the enthalpy of the bulk air stream. As the air devaporizing or subcooling tubes 55 are served directly by the outdoor air entering the open top of the main condenser chamber 25 by virtue of the downward flow of this stream of air, both air enthalpies discussed in the preceding sentence will be lower and their difference greater. Accordingly, more heat will be transferred and a lower temperature of the air-vapor mixture will be achieved, resulting in maximum devaporization.

A portion of the liquid condensing in these air devaporizing or subcooling tubes 55 may flow back through these same tubes in the form of open streams onto a shelf or partition 49 in the condensate header 45 and thence through weep holes w provided in that shelf or partition 49, in order to reach the condensate outlet chamber 46 and join the, condensate discharged into this chamber by the main condenser tubes 43. The remaining portion of the liquid condensing in these air devaporizing or subcooling tubes 55 will be entrained by the air-vapor mixture into the condensate collecting chamber 58. The air-vapor mixture (with reduced vapor) continues through the matted strand screen 66 in the air outlet header 40 which removes any entrained liquid therefrom.

This entrained liquid, plus any liquid condensing in the air outlet header 40, flows to the bottom of this header and through the reflux drain pipes 61 back into the condensate header 45 to join the liquid previously condensed in flowing out through the outlet 51 to the hot well (not shown). A lower pressure obtains in the condensate collecting chamber 5d of the air outlet header 4%) than in the condensate header 45, due to the pressure drop along the air devaporizing or subcooling tubes 55. To permit the reverse flow of condensate in the reflux drain tubes 61 against this pressure drop, and at the same time otherwise isolate these headers from each other, each reflux drain tube is provided somewhere along its length with a vertical leg 62 in which a column of liquid 63 forms, the height of this column being determined by the pressure drop. This column of liquid 63 isolates the headers 4-0 and 4-5 from each other and permits the flow of condensate from the lower to the higher pressure header.

With the assumed dry and wet bulb ambient air conditions and the assumed condensing temperature of 101 F. and condensing pressure of 2" Hg absolute, the air, saturated with vapor, would enter the first stage ejector 68 at a pressure of approximately 1.9" Hg absolute and at 92 F. The mixture of this air with the steam driving the ejector 68 results in increased outlet pressure and temperature at the discharge from the ejector, say, in the order of 6" Hg absolute and 190 F.

This air-vapor mixture from the outlet line 70 of the first stage ejector 68 enters the inlet header 39a of the condenser 38a and passes through the tubes 43a in which condensation takes place, the condensate entering the condensate outlet chamber 46a of the condensate header 45a and the condensate flowing out at 51a into the hot well (not shown) which maintains a vacuum in the condensate header 450. Under the assumed operating conditions the condensing pressure in these condensing tubes 43:: would be in the order of 6" Hg absolute and the condensing temperature would be in the order of 141 F. and with the assumed ambient air conditions of 75 F. wet bulb and 90 F. dry bulb, the temperature of the recirculating spray water from the body 86 would be in the order of 107 F., this recirculating water wetting the tubes 43a and evaporating thereon to provide the principal cooling effect in condensing the vapor passing therethrough. The air-vapor mixture from the condenser outlet chamber 46a in the condenser header 45a passes through the screen 50:! of matted metal strands to remove any entrained liquid therefrom and the resulting air-vapor mixture entering the air-vapor chamber 43a leaves through the air devaporizing or subcooling tubes 55a above the condensing tubes 43a and through which the air-vapor mixture from the condensing tubes passes before reaching the second stage steam ejector 63a.

As with the main condenser 38, a feature of the intercondenser 38a is that these air devaporizing or subcooling tubes 55a are served directly by the fresh air entering the shell by virtue of the downward flow of this stream of air. The cooling effect of this fresh entering air is at its maximum with the result that the subcooling of these devaporizing or subcooling tubes 55a is greater than if these tubes were downstream from the main condenser tubes 43 with reference to the air stream. Accordingly maximum devaporization of the air is obtained in these tubes with the direct use of fresh air over the wet external tube surfaces.

A portion of the liquid condensing in these devaporizing or subcooling tubes 5541 may flow back through these same tubes in the form of open streams onto a shelf or partition 94a in the condensate header 45a and thence through weep holes w provided in that shelf or partition 45a, in order to reach the condensate outlet chamber 46a and join the condensate discharged into this chamber by the intercondensing tubes 43a. The remaining portion of the liquid condensing in these devaporizing or subcooling tubes 55a will be entrained by the air-vapor mixture into the condensate collecting chamber 58a.

The air-vapor mixture continues through the matted strand screen 60a in the air outlet header a which removes any entrained liquid therefrom. This entrained liquid, plus any liquid condensing in the air outlet header 40a, flows to the bottom of this header and through the reflux drain pipes 61a back into the condensate header a. to join the liquid previously condensed in flowing out through the outlet 51a to the hot well (not shown). A lower pressure obtatins in the air outlet header 40a than in the condenser header 45a, due to the pressure drop along the air devaporizing or subcooling tubes a. To permit the reverse flow of condensate in the reflux drain tubes 61:: against this pressure drop, each reflux drain tube is provided somewhere along its length with a a vertical leg 62a in which a column of liquid 63a forms, the height of this column being determined by this pressure drop. This column of liquid 63a isolates the headers 40a and 45a. from each other and permits the flow of condensate from the lower to the higher pressure header.

With the assumed operating conditions, the air, saturated with water vapor, would enter the second stage ejector 63a at a pressure of approximately 5.5 Hg absolute at 120 F. The mixture of this air with the steam driving the second stage ejector 6811 results in increased outlet pressure and temperature in the ejector, say, in the order of 31" Hg absolute and 230 F.

This mixture of air and steam is continued via the line 71 to the inlet header 75 of the aftercondenser 72 and passes through the finned serpentine tubes 76 thereof to its outlet header 78 and drain 80 which leads to atmosphere with the downward drain 81 and upward vent 82. This aftercondenser is served by the atmospheric air at the assumed 90 F. dry bulb, the condensate leaving the drain 80 at 212 F. and the non-condensible gas being discharged into the atmosphere.

Features of the Condenser From the foregoing it will be noted that the present vacuum producing condenser is characterized, as compared with patented condenser, by the following features:

Separate streams of fresh air serve the main condenser 33, intercondenser 38a and aftercondenser 72 thereby to provide the maximum cooling effect for each.

With both the main condenser 38 and intercondenser 38a, the fresh air first passes the

air devaporizing tubes

55 and 55a thereby to reduce the temperature of these tubes to the minimum with maximum devaporization of the air passing therethrough. The stream is thereafter used to cool the

principal condensing tubes

43, 43a.

Since the normal separation of uncondensible gas is upwardly from the condensate with the gas devaporization tubes above the principal condensing tubes, this serving of the gas devaporization with fresh air is achieved by downward movement of the air first past the gas devaporization tubes and then past the principal condensing tubes.

With downward flow of air and downward discharge of the spray water, the movement is concurrent with each other.

The barrier screens of matted metal strands across the

headers

45, 40, 45a and 40a served to separate the airvapor mixtures from the condensate, particularly as to any entrained condensate and forms a very simple means for effecting such separation.

The vertical legs 62 of the reflux or condensate drain tubes 61 produce liquid seals 63 which permit movement of the condensate from a lower pressure to a higher pressure header but otherwise isolates these headers from each other.

The segregation of the lower temperature water 85 serving the main condenser 38 from the higher temperature water 86 serving the intercondenser 38a avoids needless raising the temperature of the water 85 serving the main condenser, with resulting increased capacity of both its gas devaporization tubes 55 and its main condensing tubes 43.

I claim:

1. A vacuum producing condenser for vapors containing non-condensible gases, comprising a shell having a main condenser chamber communicating with the atmosphere at its top and with the interior of the shell at its bottom and also having an intercondenser chamber communicating with the atmosphere at its top and with said interior of said shell at its bottom and also having a sump at its bottom for spray water falling from said chambers, means discharging air from said interior of said shell to create a downward flow of outside air through each of said chambers, main condenser tubes across said main condenser chamber having an inlet for the steam to be condensed and having an outlet, a first spray tree above said main condenser tubes to discharge water downwardly thereon, a steam jet ejector, means connecting said outlet of said main condenser tubes with the suction inlet of said steam jet ejector, intercondenser tubes across said intercondenser chamber and having an outlet and having an inlet connected to the discharge of said steam ejector, a second spray tree above said intercondenser tubes to discharge water downwardly thereon, and means recirculating water from said sump to said spray trees.

2. A vacuum producing condenser as set forth in claim 1 wherein said shell has an aftercooler chamber open to the atmosphere on one side and to said interior of said shell at its other side, and additionally including a second steam jet ejector, means connecting the suction inlet of said second steam jet ejector with said outlet of said intercondenser tubes, an aftercondenser in said afterconser chamber and having an inlet and an atmospheric outlet and means connecting the discharge of said second steam jet ejector with said inlet of said aftercondenser.

3. A vacuum producing condenser as set forth in claim 1 wherein said means for discharging air from the interior of said shell comprises means providing a plenum chamber open to the atmosphere at its top and to said interior of said shell at its bottom and arranged between said main condenser and intercondenser chambers, and fan means in said plenum chamber propelling the air therein upwardly.

4. A vacuum producing condenser as set forth in claim 1 wherein said sump has a partition dividing it into two sections with means leading the spent spray water from said main condensing chamber to one of said sections and means leading the spent spray water from said intercondenser chamber to the other of said sections and wherein said water recirculating means includes a first pump moving water from said one of said sump sections to said first spray tree and a second pump moving water from said other of said sump sections to said second spray tree.

5. A vacuum producing condenser as set forth in claim 1 wherein said means connecting the outlet of said main condenser tubes with said steam jet ejector includes a bundle of gas devaporizing tubes arranged in said main condenser chamber above said main condenser tubes and wherein said first spray tree discharges water downwardly on said gas devaporizing tubes.

6. A vacuum producing condenser as set forth in claim 5 additionally including a second steam jet condenser and means connecting the suction inlet thereof with said outlet of said intercondenser.

7. A vacuum producing condenser as set forth in claim 6, said means connecting the suction inlet of said second steam jet injector with said outlet of said inter- 10 condenser includes a bundle of gas devaporizing tubes arranged in said intercondenser chamber above said intercondenser tubes and wherein said second spray tree discharges water downwardly on said last mentioned bundle of gas devaporizing tubes.

8. In a vacuum producing condenser for vapors containing non-condensible gases, a shell having a condenser chamber communicating with the atmosphere at its top and with the interior of said shell at its bottom, a sump at the bottom of said shell collecting spray water falling from said condenser chamber, means discharging air from said interior of said shell to create a downward flow through said condenser chamber, a bundle of condenser tubes across said condenser chamber, an inlet header at the inlet end of said bundle of condenser tubes, a condensate header at the outlet end of said bundle of condenser tubes and having a portion projecting above said bundle of condenser tubes, a return header above said inlet header, a bundle of gas devaporization tubes across said condenser chamber and connecting the return header with said portion of said condensate header projecting above said bundle of condenser tubes, a steam jet ejector having its suction inlet connected to said return header, a spray tree above said bundle of gas devaporization tubes to discharge water downwardly on said bundles of gas devaporization and condenser tubes, and means recirculating water from said sump to said spray trees.

9. The combination set forth in claim 8 additionally including a screen across the interior of said condensate header through which the mixture of vapor and gas is required to pass before entering said bundle of gas devaporization tubes.

10. The combination set forth in claim 9 wherein said screen is in the form of intertwined strands.

11. The combination set forth in claim 10 additionally including a second screen of intertwined strands across the interior of said return header and through which the mixture of vapor and gas is required to pass before entering said steam jet ejector.

12. The combination set forth in claim 8 including a reflux drain tube connecting the bottom of said return header with the interior of said condensate header and wherein said reflux drain tube includes a vertical leg adapted to support a column of liquid the height of which is determined by the differential in pressure between said headers.

Graham Feb. 6, 1934 Deverall Dec. 8, 1953