US3813037A

US3813037A - Closed condensate system

Info

Publication number: US3813037A
Application number: US00262272A
Authority: US
Inventors: M Bekedam
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-06-13
Filing date: 1972-06-13
Publication date: 1974-05-28
Anticipated expiration: 1991-05-28

Abstract

A closed condensate system for steam in which the steam from a boiler is used for hot water heating, air conditioning, laundries, domestic hot water in hospitals and large office buildings, where all of the steam from the boiler is used and all of the condensate from the steam can be returned to the boiler. A closed cycle condensate receiver is used in the system and novel means is used for maintaining a pressure within the receiver so that the temperature of the condensate returned to the receiver will always be lower than the corresponding pressure within the receiver. This assures that the closed condensate system returns the condensate from the heat exchanging elements of the system back to the boiler without flash loss.

Description

O Unite States atent [111 3,813,037 Bekedam May 28, 1974 CLOSED CONDENSATE SYSTEM Primary ExaminerWilliam E. Wayner [76] Inventor: Martin Bekedam, PO. Box 10266, Assisan' w' Orinda, Calm 94610 Attorney, Agent, or Fzrm-William R. Piper [22] Filed: June 13, 1972 [57] ABSTRACT [21] Appl. No.: 262,272

A closed condensate system for steam in which the steam from a boiler is used for hot water heating, air [52] Cl 237/9 SS/DIG- 55/239 conditioning, laundries, domestic hot water in hospi- 237/67 tals and large office buildings, where all of the steam [51] It ll. Cl. F2441 1/00 from the boiler is used and n of the condensate from [58] Fleld of Search 237/9 R, 67, 68; the Steam can be returned to the boiler A Closed SS/DIG- 239 cycle condensate receiver is used in the system and novel means is used for maintaining a pressure within [56] References cued the receiver so that the temperature of the condensate UNITED STATES PATENTS returned to the receiver will always be lower than the 1,572,482 2/1926 Hoffman 237/68 corresponding pressure within the receiver This l,777,333 10/1930 Simpson 237/67 sures that the closed condensate system returns the 2,71 07 9/ 5 Arb gas 2 7/9 condensate from the heat exchanging elements of the 9 3 4/1960 Stiers 122/l C system back to the boiler without flash loss. 2,942,785 6/1960 Arbogast 237/9 4 Claims, 6 Drawing Figures PATENTEOHAY 28 m SHEET 2 BF 3 if z: db

CLOSED CONDENSA'IE SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention In a closed condensate steam system where the boiler delivers steam to various units and the condensate from these units is returned back to the boiler, it is difficult to prevent the flashing of some of the condensate into steam as the condensate is returned to a closed cycle receiver that forms a part of the system. This is due to the fact that the temperature of some of the condensate is at a higher temperature than the corresponding pressure within the receiver. I provide novel means in the closed cycle receiver for delivering any returning condensate directly'into the body of condensate already in the receiver and for releasing any gases in the condensate into the gas receiving portion of the receiver without forcing these gases to pass through any substantial portion of the condensate.

2. Description of the Prior Art The patent to Vern E. Stiers, No. 2,931,344, issued Apr. 5, 1960, discloses a closed condensate return and boiler feed system. This system includes a branch steam pipe and any steam entering this pipe is not returned to the system as a condensate. Also, the patent discloses a collector positioned in the upper half of a condensate receiver. This collector receives the condensate and it has a slot for releasing any gases in the condensate and permitting these gases to pass directly into the upper half of the receiver. The condensate in the collector either flows directly into a pipe that returns the condensate to the primary receiver in the system or the condensate will overflow the collector and be received in the condensate receiver in which the collector is mounted. The collector does not deliver the condensate directly into the body of condensate.

In my present closed condensate steam system a novel means is provided for delivering any condensate directly into the body of condensate in the closed cycle receiver and any gases in the condensate will be released from the condensate at the surface level of the body of condensate in the receiver where the gases can immediately escape into the gas receiving portion of the receiver and not be forced to pass through any appreciable portion of the body of condensate in the receiver. The temperature of the condensate entering the receiver can be higher or lower thanthe corresponding pressure within the receiver. It it is higher the condensate will blend with the condensate in the receiver and the steam will separate from the condensate and will enter the steam receiving portion of the receiver. Therefore, there can be no flashing of the condensate as it enters the receiver. The Stiers patent was designed to operate at one common operating pressure whereas my system can operate on all process equipment having different pressures.

SUMMARY OF THE INVENTION An object of my invention is to provide a closed cycle condensate steam system in which a closed cycle receiver forms a part of the system and receives the condensate. The system is designed so that the temperature of the condensate will always be lower than the corresponding pressure within the receiver. Since all of the condensate is returned to the receiver and the condensate in the receiver is pumped to a steam boiler which forms a part of the system, the entire system will operate as a complete closed cycle system.

A further object of my invention is to provide a pressurized closed cycle condensate system that can receive condensate from various process equipment at different pressures and temperatures while preventing the condensate in the closed cycle receiver from flashing. The system will operate at a pressure in relation to the highest pressure in the process equipment in use since no steam is added to the system in order to keep it pressurized. The closed condensate system can be installed on existing equipment regardless of whether the condensate lines have no restriction from each process equipment or whether they have traps, control valves, or an orifice system.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical longitudinal section through the closed cycle receiver that forms a part of the closed cycle condensate system.

FIG. 2 is a horizontal section taken along the line 22 of FIG. 1.

FIG. 3 is an enlarged horizontal section taken along the line 3-3 of FIG. 1.

FIG. 4 is a diagrammatic showing of the entire closed cycle condensate system.

FIG. 5 is a vertical longitudinal section through a modified form of the closed cycle receiver that forms a part of the closed cycle condensate system.

FIG. 6 is a horizontal section taken along the line 6-6 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In carrying out my invention, I will first describe the novel construction of my closed cycle receiver and then will set forth how it is connected into a closed cycle condensate system and how the system operates. I show a longitudinal vertical section through the closed cycle receiver A, in FIG. 1, and FIG. 2 shows a horizontal longitudinal section which is taken along the line 22 of FIG. 1. A plurality of closed

condensate return pipes

1, 2, 3 and 4 enter through the upper half of the cylindrical casing of the receiver A and have their lower ends la, 2a, 3a and 4a, respectively, terminate at the water line 5, as clearly shown in FIG. 1. I do not wish to be confined to only four condensate return pipes l to 4 inclusive because my condensate receiver can accommodate one or more such pipes and l have illustrated four of them only by way of example.

FIGS. 1 and 2 show the portions of the

condensate return pipes

1, 2, 3 and 4 that extend into the upper portion of the condensate receiver A as being enclosed in

larger diameter sleeves

6, 7, 8 and 9, respectively, and these sleeves are open both at their upper and lower ends. The upper ends 60, 7a, 8a and 9a of the

sleeves

6, 7, 8 and.9, respectively, extend into the upper portion of the condensate receiver A and are spaced a slight distance below the cylindrical casing of the receiver. Also, the lower ends 6b, 7b, 8b and 9b of the sleeves 6 to 9 inclusive extend below the

lower ends

10, 2a, 3a and 4a of the condensate return pipes l to 4 inclusive and project into the lower portion of the receiver A so as to be submerged in the liquid contained in this portion. FIG. 1 shows the lower ends of the sleeves being spaced a slight distance above the inner surface of the adjacent casing portion of the receiver A.

The

sleeves

6, 7, 8 and 9 may be secured to their respective condensate return pipes l, 2, 3 and 4, respectively, in any manner desired. In FIG. 3, I show by way of one exam ple the sleeve 7 having a portion ofits inner surface contacting and welded to the adjacent outer surface of the condensate return pipe 2 at X. This will provide a sufficient support for the sleeve 7 and the greater portion of the sleeve will be spaced from the pipe 2 so as to provide an internal passage Y that extends from the lower end 2a of the pipe 2 up to the upper end 7a of the sleeve 7. Therefore, any condensate flowing through the pipe 2 in a manner hereinafter described will enter the receiver A at the water line 5, and any gases or steam will immediately escape into the upper portion of the receiver A by flowing through the passage Y and out through the upper end 7a of the sleeve 7, while the liquid condensate flowing from the pipe 2 will pass downwardly through the sleeve 7 and out through the open lower end 7b of the sleeve so as to mix with the liquid in the lower portion of the receiver A. The advantage derived from this particular construction will be set forth hereinafter. The other sleeves 6, 8 and 9 are connected to their

pipes

1, 3 and 4, respectively, in the same manner as described and illustrated for the pipe 2 and sleeve 7.

In FIG. 4, I schematically show the closed cycle receiver A connected into a closed cycle condensate system. A pipe 10 leads from the bottom of the receiver A to a pump B. The pump delivers the liquid into a pipe 11 which in turn connects with a boiler, shown diagrammatically at C. A control valve D is placed in the pipe 11 and determines when fluid is to be delivered into the boiler C. Water will be delivered to the boiler C until the water in the boiler is at the correct level. Any type of boiler C may be used. The closed cycle receiver A can have water added to it through a fill line 12 until the water reaches the level 5. It should be noted that the water level 5 lies in the same horizontal plane as that occupied by the

lower ends

1a, 2a, 3a and 4a of the condensate return pipes l to 4 inclusive. A valve 13 controls the flow of new water through the pipe 12. The valve 13 is closed when the closed cycle receiver A is half full of water.

The boiler C has a steam line 14 which conveys steam at a boiler operating pressure through one or more branch lines 14a and 14b to temperature control valve E and E, respectively. The branch line 14a leads to a water heat exchanger, shown diagrammatically at F and the branch line 14b leads to a laundry heat exchanger, indicated diagrammatically at G in FIG. 4. The condensate from the heat exchangers F and G flows through traps H respectively, and returns through the lines or pipes 1 and 2, respectively, to the closed cycle receiver A. As already stated, the steam line 14 and branch lines 14a and 14b can communicate with one or more heat exchangers F and G, and I have illustrated two of them by way of example.

Steam from line 14 also flows through branch lines 14c and 14d to pressure reducing valves J and J, re-

spectively, see diagrammatic FIG. 4. The valve J supplies low pressure steam to a temperature control valve K that in turn supplies steam to a domestic hot water heat exchange L and the valve K supplies low pressure steam to a liquid absorption chiller heat exchanger L. The condensate from the heat exchanger L passes through a trap M and through a pipe 15 to a closed receiver N. In like manner the condensate from the heat exchanger L passes through a trap M and a pipe 16 to a closed receiver N.

A condensate pump P is mounted under the receiver N and a pipe connects the pump to the bottom of the receiver so as to deliver any condensate in the receiver to the pump. A pipe 17 leads from the pump P and connects with the pipe 4 by means of a T 18. A check valve R is mounted in the pipe 4 and permits a flow of condensate or gases toward the closed cycle receiver A and prevents any return flow. Another pipe 19 communicates with the top of the receiver N and is connected to the pipe 4 by the T 18. The pipe 19 has a check valve Q mounted therein and permits a flow of any gases from the top of the receiver N through the pipe 19 and into the pipe 4 and prevents any return flow.

When the pump P operates, it will force condensate through the pump discharge pipe 17 past the check valve R and through the pipe 4 and into the closed cycle receiver A. The check valve Q will close and prevent any of this condensate from being returned to the receiver N through the pipe 19. When the pump P stops, some of the condensate in the pipe 17 will return to the receiver N until the level of the condensate in the pipe 17 will be at the same level as the condensate in the receiver. The check valve Q will permit gases in the top of the receiver N to enter the pipe 19 and to also enter the portion of the pipe 17 that is not filled with condensate. Therefore, when the pump P again is operated, the gases in the pump discharge pipe 17 that are disposed above the condensate level in the pipe will be forced through the pipe 4 and into the closed cycle receiver A because the check valve Q will prevent these gases from being returned to the receiver N.

The liquid absorption chiller heat exchanger L, shown in FIG. 4, is provided with a trap M, the pipe 16 and the closed receiver N. This receiver N has the same apparatus associated therewith for returning the non-condensable gases and the condensate back to the closed cycle receiver A by means of the condensate pipe 3, as the receiver N has for returning its gases and condensate back to the receiver A through the pipe 4. Therefore, similar parts will be given similar character designations except that they will be primed and no further description of this portion of the apparatus need be given.

Any condensed steam in the steam line 14 will pass into a trap S, see FIG. 4, and will flow through condensate return line 20 that communicates with the closed cycle receiver A at its top. I will now set forth the reason for positioning the outlet ends 1a to 4a inclusive of the condensate return pipes 1 to 4 inclusive at the fluid level 5 in the closed cycle receiver A, and why these outlet ends are received in larger diameter sleeves 6 to 9 inclusive whose upper ends 6a to 9a inclusive open into the receiver A and are disposed above the liquid level 5, and whose lower ends 6b to 9b inclusive extend down into the liquid in the receiver A.

When steam is condensed, there is a direct relationship between the pressure of the condensate and its temperature. For example, the condensate from the hot water heating heat exchanger F and the condensate from the laundry heat exchanger G have a pressure of I00 PSIG (pressure per square inch gauge) and a corresponding temperature of 338F. The condensate from the domestic hot water heat exchanger L has a pressure of 35 PSIG at a corresponding temperature of 281F. The condensate from the liquid absorption chiller heat exchanger L has a pressure of PSIG at a corresponding temperature of 250F. Assume that the minimum condensate from the heat exchangers F and G is 50 gallons, the minimum condensate from the heat exchanger L is 35 gallons and the minimum condensate from the heat exchanger L is 15 gallons, then adding these numbers of gallons together we have 100 gallons of condensate being delivered to the closed cycle receiver A. Therefore, the average temperature of the condensate in the receiver A is 304.85F.

Some of the condensate from the highest operating pressure heat exchangers F and G at 100 PSIG will flash when the pressure within the closed cycle receiver A is lower than this pressure. This steam will escape from the outlet ends la and 2a of the pipes 1 and 2 and will immediately rise in the sleeves 6 and 7 that enclose the pipes 1 and 2, respectively, and will be delivered into the upper portion of the receiver A. All of the low pressure and low temperature condensate received from the heat exchangers L and L will flow through the

pipes

4 and 3, respectively, and will pass directly into the condensate that is already in the receiver A. This will cause a lowering of the temperature of the condensate in the receiver and will result in the condensate having a lower temperature than its corresponding pressure.

It will be seen that I have provided a closed cycle condensate system wherein the temperature of the condensate in the closed cycle receiver A, in FIG. 4, will always be lower than the corresponding pressure within the receiver without the addition of new makeup water. Since all of the condensate in the system is returned to the receiver A, the system will operate as a complete closed cycle system. The pressurized system can be manufactured on a low stand which can fit into a room having an 8 foot ceiling since the boiler feed pump B will not flash because the water temperature in the receiver A is always lower than the corresponding pressure. The boiler feed pump B will therefore not flash when the system has a slight pressure drop and the pressure-temperature relationship no longer correspond to each other. The closed cycle condensate system can receive condensate from various process equipment at different pressures and temperatures and the condensate in the receiver A will not flash. The system will ope rate at a pressure in relation to the pressure of its highest process equipment in use since no steam is added to the system to keep it pressurized. My pressurized closed cycle condensate system can operate when installed on existing equipment regardless of whether the condensate lines have any restriction from each process equipment or if they have traps, control valves, or orifices.

In FIGS. 1 and 4, I show the closed cycle receiver A provided with a control unit U, called an air vent, which will only release non-condensable gas from the receiver and prevents any steam from escaping. If the system is not being used or when it is in a no-Ioad condition, condensate from the main line trap S will add a small amount of condensate to the receiver A through the pipe 20, which will tend to bring the condensate in the receiver to a pressure-temperature relationship. During this low flow period of the condensate returning to the receiver, radiation loss will keep the corresponding temperature of the condensate in the receiver below the corresponding pressure within the receiver. If traps are not used with the various units, check valves will be used in their place so as to prevent steam from back-flowing from the receiver A to the other units through the

condensate return pipes

1, 2, 3 and 4.

In FIGS. 5 and 6, I show a slightly modified form of the invention. The

condensate return pipes

1, 2, 3 and 4 enter the top of the closed cycle receiver A, in FIG. 5, as they do in the form shown in FIG. 1. However, instead of the pipes l to 4 inclusive having their outlet ends terminate at the liquid level 5, as in FIG. 1, these pipes have portions lb, 21), 3b and 4b bent at right angles so as to provide horizontal portions that are disposed at the liquid level 5 in FIG. 5. Then these horizontal pipe portions lb to 4b inclusive communicate with

short length pipes

31, 32, 33 and 34, respectively. These short length pipes take the place of the sleeves 6 to 9 inclusive, shown in FIG. I. They have their upper open ends 31a to 34a inclusive spaced a slight distance from the top of the receiver A and they have their lower open ends 3111 to 34b inclusive extending into the body of liquid and being spaced a slight distance from the bottom of the receiver. In all other respects the closed cycle receiver A is similar to the receiver shown in FIGS. 1 and 2, and it is connected into the closed cycle condensate system in the same manner as illustrated in the schematic view of FIG. 4. Therefore, it will be unnecessary to show another schematic view.

The operation of the modified form of the closed cycle receiver A, shown in FIGS. 5 and 6, is substantially the same as that described for the form shown in FIGS. 1 to 4 inclusive. The condensate return pipes l to 4 inclusive, in FIG. 5, will deliver the condensate to the right angle bent portions lb to 4b inclusive, which are placed at the liquid level 5 in the receiver A. As the condensate enters the short length pipes 31 to 34 inclusive, non-condensable gases inthe condensate or any flashing of any portion of the condensate will be released to the upper portions of these pipes and will pass into the upper part of the receiver A through the open tops 31a to 34a of these pipes. Also, the condensate from the pipes I to 4 inclusive will enter the short pipes 31 to 34 inclusive and will flow out through the open bottoms of these pipes and be received in the body of liquid in the receiver. 7

In the diagrammatic showing of the closed cycle condensate system in FIG. 4, the condensate received from the hot water heating heat exchanger F and the laundry heat exchanger G can be returned to the closed cycle receiver A by gravity through the pipes 1 and 2, since the two heat exchangers are disposed above the receiver A. Where the units are disposed on a level with or below the receiver A, pumps are used for returning the condensate to the receiver. Both of the heat exchangers L and L' deliver their condensate to closed receivers N and N, respectively, and since these receivers are on a level with or are disposed below the closed cycle receiver A, pumps P and P are used for pumping the condensate into the receiver A through the

pipes

3 and 4, respectively. The pump B that pumps the condensate from the receiver A back to the boiler C will not flash because the temperature of the condensate is lower than the corresponding gaseous pressure. The receiver A can receive condensate from various process equipment at different pressures and temperatures and the condensate in the receiver will not flash because the temperatures of the condensates returned to the receiver will always be lower than the corresponding gaseous pressure in the receiver.

1 claim:

1. In a closed cycle condensate system including:

a. a closed cycle condensate receiver having a body of liquid of less capacity than that of the receiver, the liquid being at a certain temperature and the remainder of the receiver capacity being filled with a gas, the surface of the liquid establishing a predetermined liquid level;

b. at least one condensate return pipe entering the top of said receiver for returning condensate at a certain temperature to the receiver;

c. means associated with said pipe for freeing the condensate from the pipe at the surface level of said body of liquid so that any gas in the condensate will immediately enter the portion of the re ceiver that holds the gas and the condensate from said pipe will be delivered directly into the liquid body without passing through any portion of the receiver that contains the gas;

d. a steam producing means forming a part of said closed cycle condensate system;

e. a heat exchanger connected to said steam producing means for receiving steam therefrom;

f. said condensate return pipe being connected to said heat exchanger for receiving condensate therefrom; and

g. a pump connected to said receiver for receiving condensate therefrom, said pump being connected to said steam producing means for delivering condensate thereto.

2. In a closed cycle condensate system including:

a. a closed cycle receiver;

b. means for supplying heated fluid to the receiver for maintaining the fluid level at a predetermined level;

0. a boiler;

d. a pump for delivering fluid from the receiver to the boiler as needed;

e. at least one unit having a steam line connecting it to said boiler for receiving steam therefrom;

f. a condensate return pipe leading from said unit back to said receiver, the end of the pipe in the receiver terminating in a horizontal portion at the liquid level in the receiver; and

g. said horizontal pipe portion communicating with a vertically extending short length pipe whose top extends above the liquid level in the receiver for permitting the escape of any gas in the condensate to pass into the space of the receiver disposed above the fluid level, and whose bottom extends into the fluid in the receiver for conveying any condensate in the condensate return pipe directly into the fluid.

3. In a closed cycle condensate system including:

a. a closed cycle receiver;

c. a boiler; I

d. a pump for delivering fluid from the receiver to the boiler as needed;

f. a condensate return pipe leading from said unit back to said receiver, the end of the pipe in the re ceiver terminating at the liquid level in the receiver; and

g. a sleeve enclosing the portion of the condensate return pipe disposed within said receiver and having an inner diameter greater than the outer diameter of the pipe for providing a passageway between the two; the top of said sleeve extending above the liquid level in the receiver for permitting the escape of any gas in the condensate to pass into the space in the receiver disposed above the fluid level, and the bottom of said extending into the fluid within said receiver for conveying any condensate in the pipe directly into the fluid.

4. A closed cycle condensate system comprising:

a. a first closed cycle receiver;

b. means for supplying heated fluid to said receiver for maintaining the fluid level at a predetermined level, the upper portion of said receiver containing gases;

c. a steam boiler;

d. a first pump connected to the receiver for receiving fluid therefrom and connected to said boiler for delivering fluid thereto;

f. a second closed receiver for holding a body of fluid of less capacity than that of said second closed receiver;

g. a condensate conveying pipe for receiving condensate from said unit and for conveying it to said second receiver;

h. a second pump for receiving condensate from said second receiver and for delivering it through a second condensate conveying pipe to said first. receiver;

i. means associated with the portion of said second pipe that enters said first receiver for freeing the condensate from the second pipe at the surface of the fluid in said first receiver so that any gas in the condensate will immediately enter the gas holding portion of said first receiver and any condensate will be delivered to the fluid in said first receiver;

j. a gas conveying pipe communicating with the upper gas holding portion of said second receiver and delivering the gas to said second pipe, said gas conveying pipe having a first check valve therein for preventing any return flow back into said second receiver; and

k. a second check valve in said second condensate conveying pipe and positioned on the down stream portion of said second pipe beyond the point where said gas conveying pipe communicates with said second pipe, said second check valve preventing any return flow in said second pipe.

Claims

1. In a closed cycle condensate system including: a. a closed cycle condensate receiver having a body of liquid of less capacity than that of the receiver, the liquid being at a certain temperature and the remainder of the receiver capacity being filled with a gas, the surface of the liquid establishing a predetermined liquid level; b. at least one condensate return pipe entering the top of said receiver for returning condensate at a certain temperature to the receiver; c. means associated with said pipe for freeing the condensate from the pipe at the surface level of said body of liquid so that any gas in the condensate will immediately enter the portion of the receiver that holds the gas and the condensate from said pipe will be delivered directly into the liquid body without passing through any portion of the receiver that contains the gas; d. a steam producing means forming a part of said closed cycle condensate system; e. a heat exchanger connected to said steam producing means for receiving steam therefrom; f. said condensate return pipe being connected to said heat exchanger for receiving condensate therefrom; and g. a pump connected to said receiver for receiving condensAte therefrom, said pump being connected to said steam producing means for delivering condensate thereto.

2. In a closed cycle condensate system including: a. a closed cycle receiver; b. means for supplying heated fluid to the receiver for maintaining the fluid level at a predetermined level; c. a boiler; d. a pump for delivering fluid from the receiver to the boiler as needed; e. at least one unit having a steam line connecting it to said boiler for receiving steam therefrom; f. a condensate return pipe leading from said unit back to said receiver, the end of the pipe in the receiver terminating in a horizontal portion at the liquid level in the receiver; and g. said horizontal pipe portion communicating with a vertically extending short length pipe whose top extends above the liquid level in the receiver for permitting the escape of any gas in the condensate to pass into the space of the receiver disposed above the fluid level, and whose bottom extends into the fluid in the receiver for conveying any condensate in the condensate return pipe directly into the fluid.

3. In a closed cycle condensate system including: a. a closed cycle receiver; b. means for supplying heated fluid to the receiver for maintaining the fluid level at a predetermined level; c. a boiler; d. a pump for delivering fluid from the receiver to the boiler as needed; e. at least one unit having a steam line connecting it to said boiler for receiving steam therefrom; f. a condensate return pipe leading from said unit back to said receiver, the end of the pipe in the receiver terminating at the liquid level in the receiver; and g. a sleeve enclosing the portion of the condensate return pipe disposed within said receiver and having an inner diameter greater than the outer diameter of the pipe for providing a passageway between the two; the top of said sleeve extending above the liquid level in the receiver for permitting the escape of any gas in the condensate to pass into the space in the receiver disposed above the fluid level, and the bottom of said extending into the fluid within said receiver for conveying any condensate in the pipe directly into the fluid.

4. A closed cycle condensate system comprising: a. a first closed cycle receiver; b. means for supplying heated fluid to said receiver for maintaining the fluid level at a predetermined level, the upper portion of said receiver containing gases; c. a steam boiler; d. a first pump connected to the receiver for receiving fluid therefrom and connected to said boiler for delivering fluid thereto; e. at least one unit having a steam line connecting it to said boiler for receiving steam therefrom; f. a second closed receiver for holding a body of fluid of less capacity than that of said second closed receiver; g. a condensate conveying pipe for receiving condensate from said unit and for conveying it to said second receiver; h. a second pump for receiving condensate from said second receiver and for delivering it through a second condensate conveying pipe to said first receiver; i. means associated with the portion of said second pipe that enters said first receiver for freeing the condensate from the second pipe at the surface of the fluid in said first receiver so that any gas in the condensate will immediately enter the gas holding portion of said first receiver and any condensate will be delivered to the fluid in said first receiver; j. a gas conveying pipe communicating with the upper gas holding portion of said second receiver and delivering the gas to said second pipe, said gas conveying pipe having a first check valve therein for preventing any return flow back into said second receiver; and k. a second check valve in said second condensate conveying pipe and positioned on the down stream portion of said second pipe beyond the point where said gas conveying pipe communicates with said second pipe, said Second check valve preventing any return flow in said second pipe.