US1332189A - System for conserving motive fluid - Google Patents

Description

w. B. FLANDERS. SYSTEM FOR. CONSERVING MOTIVE FLUID.

APPLICAHQN FILED l w-VH2, H915- Patented Feb. 24,1920.

INVENTOR.

HIS ATTORNEY IN FACT:

WARREN B. FLANDERS, OF HABANA, CUBA,

ASSIGNOR TO WESTINGHOUSE ELECTRIC MANUFACTURING 00., A CORPORATION OF PENNSYLVANIA.

SYSTEM FOR CONSERVING MOTIVE FLUID.

Application filed July 22,

To all whom it may concern Be it known that I, WARREN B. FLANDERS, a citizen of the United States, and a resident of Habana, Cuba, have made a new and useful Invention in Systems for Conserving Motive Fluid, of which the following is a specification.

This invention relates to the conservation of motive fluid, hereinafter called steam, and particularly to the conservation of steam in power plants in connection with the feed water heating systems.

An object of this invention is to provide simple and improved means for venting air or other non-condensable gases from feed water heaters and particularly heaters which are continuously or at times during their operation subjected to pressures above atmosphere.

A further object is to provide a heater which may be employed in connection with steam conserving apparatus and in which simple and improved means are employed for discharging air and non-condensable gases without wasting steam.

A further object of the invention is to produce a new and improved feed water heating system in which means are employed for maintaining the pressure of the steam delivered to the feed water heater substantially constant and in which simple and improved means are employed for venting air or non-condensable gases delivered to the feed water heater.

A further object is to produce a system for heating feed water and for conserving the steam available for heating the feed water, in which improved means are employed for venting air and non-condensable gases introduced into the system with the steam or with the water to be heated.

These and other objects, which will be made apparent throughout the further description of my invention are attained by means of a feed water heating system herein described and illustrated in the drawings accompanying and forming a part hereof.

In the single sheet drawing I have illustrated diagrammatically in Figure 1 a feed water heating system which forms an embodiment of my invention.

Fig. 2 is a diagrammatic sectional view on the line 2-2 of a part of the apparatus illustrated in Fig. 1. g I

In power plants, or similar installations,

Specification of Letters Patent.

Patented Feb. 24, 1920.

1915. Serial No. 41,285.

it is customary to deliver the steam exhausted from the steam driven auxiliaries to a feed water heater, where it is employed in heating the water prior to its delivery to the steam generators. It will be apparent that if the exhaust steam so delivered to the heater is sufficient in quantity to heat the feed water to a determined temperature during periods of full load on the steam generators, it will be in excess during periods of light load, since the load on the generators varies in approximately direct ratio to variations in the load on the prime movers or main power developing units, whereas the amount of steam exhausted from the auxiliaries remains substantially constant regardless of variations in the load on the prime movers. On the other hand, if the number of auxiliaries, delivering exhaust steam to the feed water heater, is so proportioned that the steam delivered to the heater during normal loads on the main power units or prime movers, is just sufii cient to be economically employed in heating the feed water, there will not be sufiicient steam to raise the feed water to the desired temperature when the main power units are developing maximum power.

In order, therefore, to conserve the steam and to increase the economy of the entire plant or installation, means have been provided for automatically delivering the excess steam which cannot be efiiciently employed in the feed water heater to a power developing mechanism or some other apparatus in which the heat of the. steam can be usefully employed. Means have also been employed for automatically augmenting the supply of heating steam by delivering additional steam to the heater when the normal source of heating steam supply is insufiicient to maintain the feed water at the desired temperature. WVith such apparatus the so-called open heater cannot be employed, since the automatic regulation of the steam supply to the heater is ordinarily accomplished through variations in the pressure of the steam supplied, and consequently the heater, although it may be of the open heater type,is subjected to pressure which at times exceeds atmospheric ressure. Under such conditions, it is di cult to effect a removal of the air and other noncondensable fluids from the heater without dissipating heat energy.

My invention overcomes this difliculty, and, as illustrated, includes a feed water heater which is adapted to receive steam under pressure and is provided with a vent port for venting air or other noncondensable gases from the heater. The vent port communicates with apparatus of such capacity that it is capable of efliciently or economically employing the fluid vented from the heater during the periods of great est fluid pressure within the heater. In the apparatus illustrated, the means for uti1izing the vented fluid is shown as an auxiliary heater which operates to condense the steam vented from the main heater and which also abstracts heat from the air or other noncondensable gases vented from the main heater.

The illustrated embodiment of my invention includes a prime mover or main power developing unit 3, which is illustrated diagrammatically as a steam turbine. The main power unit is illustrated as exhausting into a condenser 4 of any type, to which condensing water is delivered by means of a pump 5, through a pipe or passage 6, the pump receiving water from a pipe 6. I have illustrated diagrammatt cally a steam turbine 7 for driving the pump 5. This turbine receives steam through a pipe or passage 8 and the steam exhausted therefrom is delivered through a pipe or passage 9 to a receiver or exhaust main 10, with which the exhaust of other steam driven auxiliaries may communicate. I have also shown another auxiliary turbine 7 arranged to discharge into the exhaust main 10 by means of a pipe 9.

A feed water heater 11 is diagrammatically illustrated in the drawings and as shown receives heating fluid from the receiver 10 through a passage 13, which is provided with a valve 13. The heater 11 is provided with an air vent port 12, which communicates with a second heater 14, shown as located above the heater 11 and to which all of the water to be heated is delivered prior to its delivery to the heater.

As illustrated, the heater 14: is of the surface or closed type and is provided with an air vent 15, which is shown as communicating with the atmosphere. Water to be heated is delivered to the heater 14 through a pipe 16, and after traversing the tubes LP of the heater 1 1, is delivered through a pipe 17 to the spray nozzles 18 of the heater 11. It will be apparent to those skilled in the art that various types of heaters may be employed and that the details of construction of both the heaters may be materially modified without in any way departing from the spirit or scope ofthe invention as set forth by the appended claims. In the drawings I have illustrated a condensate return pipe 14 communicating with the heater 14: and

with the heater.11 below the normal water level of that heater. Other means may be employed for disposing of the water of condensation, but where an open communication such as illustrated is employed, the heater 14 should be raised above the heater 11 a suflicient height to prevent water from being forced from the heater 11 into the heater 14.

The working passage of the turbine 3 communicates with the receiver 10 through a system of piping 19. As illustrated, the piping 19 includes an ordinary form of valve commonly known as a constant pressure or heat balance valve, which is diagrammatically illustrated at 21. A valve such as that disclosed by the Patent No. 1,198,635 to Francis Hodgkinson may be employed as the valve 21. The pipe also includes a manually operated valve 22 for permanently shutting off communication between the turbine and the receiver and the receiver may and preferably will be provided with a safety or pop-off valve 19 such as is ordinarily employed for relieving excessive pressure. The valve 21 is so arranged that it will open in response to the pressure of the fluid in the receiver 10 and deliver fluid therefrom to the turbine 3, when the pressure within the receiver exceeds a determined pressure. It may also be arranged to open in response to a decrease in pressure within the receiver 10 and to admit augmenting fluid or steam from the working passage of the turbine 3 to the receiver. The valve above referred to, patented to Hodgkinson, embodies these features. For this reason, the piping 19 preferably communicates with the working passage of the turbine at such a point that the pressure normally existing at the point of connection is substantially equal to the pressure which it is desired to maintain within the receiver 10.

In Fig. 2, I have shown such a connec tion. As shown, the turbine 3 is provided with two sections 3 and 3 which operate in series. An annular chamber 3 is in open communication with the working passages of the turbine between the two sections 3 and 3 Consequently it is a point of intermediate pressure to which auxiliary low pressure steam may be admitted or from which low pressure steam may be with drawn. The piping 19 is shown connected to the annular chamber 3.

Assume for the purposes of description that 100,000 pounds of water are to be heated per hour from 100 F to 216 F. and that the receiver 10 receives 20,000 pounds of exhaust steam per hour from the various sources communicating with it. Assume also that the constant pressure or heat balance valve 21 is so adjusted that it will not open in response to an excess of pressure in the receiver 10 until the pressure in the receiver is equal to or exceeds 16 pounds absolute. Under such conditions a pressure of 16 pounds absolute will be normally maintained in the heater 11, and steam will flow from the heater through the vent pipe 12 to the heater 1 1 in which atmospheric pressure (14.7 pounds absolute) is maintained due to the vent 15 being open to the atmosphere.

Assume also that the pipe 12 is of such size that under the conditions above set forth approximatel 2000 pounds of steam per hour will flow from the heater 11 to the heater 14. The steam entering the heater 14 will be condensed therein by the 100,000 pounds of water passing therethrou'gh and the temperature of the water will be raised from 100 to 119.35, which as is apparent is not sufficient rise in temperature to cause the formation of scale in the heater 14: and consequently a surface heater such as illustrated may be employed. The water after passing through the heater to the heater 11, where it is mixed with the steam entering the heater from the receiver 10. As a result of the mixture of the steam and water approximately 10,000 pounds of steam are condensed and thewater is itself heated to 216 F. 2000+10,000 pounds, 2'. 6., 12,000 pounds of the available steam can be employed in heating the feed water, the remaining 8000 will cause the constant pressure valve 21 to lift and the excess steam will be delivered to the main power developing unit and will do useful work therein in expanding to condenser pressure. It will be obvious that whenever there is more steam available than can be condensed in the two heaters 11 and 141 that the pressure in the ex haust or receiver 10 and in the heater 11 will be at least equal to the pressure required to lift or open the constant pressure valve 21 and if there is less steam than can be condensed in the two heaters, the vent openings 12 and 15 will prevent the pressure falling below atmosphere in the exhaust steam system. The constant pressure valve may be so adjusted that as soon as the pressure in the exhaust main or receiver 10 falls below 15 pounds absolute, it will open and deliver steam from the main power unit to the receiver and thereby maintain approximately 16 pounds pressure in the receiver.

From the above description it will be apparent that by properly proportioning the vent or passage 12 of the heater 11, with respect to the capacity of the heater 1 1, the heater 11 will not only be properly vented, but all of the steam delivered to it will be efficiently employed in heating the feed water. As is apparent from the above description, the vent passage 12 and 14:, is delivered Inasmuch as only delivering actuating mechanism of the valve 21 should be so proportioned that the valve 21 will open and relieve the pressure, within the receiver 10 or heater 11, when the pressure conditions are such that the vent passage 12 will pass more fluid than the apparatus communicating with it is capable of efiectively utilizing. While Ihave shown the heater 14 arranged to deliver the water passing through it to the heater 11, it will be apparent that this water may be utilized elsewhere after it is heated by the heater 1a and that the heater 14 may be replaced by any apparatus capable of utilizing low pressure fluid. It will also be apparent that various changes, modifications, substitutions, additions and omissions may e made in the apparatus illustrated without departing from the spirit and scope of the invention as set forth by the appended claims.

What I claim is:

1. In combination with an open feed water heater, a passage to which low pressure motive fluid is delivered and with which said feed water heater communicates, a steam utilizing power having the low pressure stage thereof communicating with said passage, and a valve between said unit and said passage for delivering augmenting fluid from the unit to the passage when the pressure in the pas-- sage falls below a determined pressure.

2. A feed water heating system comprising a feed water heater having an atmospheric vent, a source of heating fluid supply communicating with said heater, a steam actuated motor communicating wit said source of heating fluid supply, and a valve located between said source an said operation to variations in the pressure at said source for delivering fluid from said source to said motor and for fluid from said motor to said source.

3. In a system of the character described, a water heater to which exhaust fluid is delivered, a power developing apparatus, an means responsive to pressure within the heater for delivering fluid from the heater to a working passage 0 the power develop ing apparatus or for delivering working fluid from the power developing apparatus to the heater to maintain the pressure within the heater substantially constant.

a. In a system of the character described, a power unit utilizing steam, an exhaust steam receiver, a feed water heater provided with an atmospheric vent and receiving steam from the receiver for heating the water in the heater, and means for diverting exhaust steam to a working passage of the power unit only when the exhaust steam necessary for the requirements of the feed water is excessive.

5. In a system of the character described,

developing unit I a power unit utilizing steam, an exhaust a feed water heater provided an atmospheric vent and receiving steam from the receiver for heating the water in the heater, and means for diverting steam from the working passage of the power unit to the receiver only when the exhaust steam necessary for the requirements of the feed water is deficient. In combination in a power system of the class described, a feed Water heater, a source of heating fluid supply of less capacity than the maximum requirements of the-heater and greater than the minimum requirements of the heater, in

responsive to pressure therein for maintaining a supply of heating fluid to the heater at substantially uniform pressure.

The combination with a jet feed water heater havinga continuously open vent and aheatmg system having means for main- WARREN B. FLANDERS.

Witnesses:

RAOUL F. WASHINGTON, L. A. CHRIsTY.

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