US1459433A - Air pump for condensers - Google Patents

Description

June 1%, 1923. Y 1,459,433

K. BAUMANN AIR PUMP FOR CONDENSERS Filed Feb. 2,v 1917 2 Sheets-Sheet -1 Fig.1.

WITNESSES INVENTOR r h QWM fix kaiiwewm K. BAUMANN AIR PUMP FOR CONDENSERS June 19, 1923.

Filed Feb. 2, 1917 2 Sheets-Sheet 2 WITNESSES Patented June 19, 1923.

KARL BAUMANN, OF URMSTON, ENGLAND, ASSIGNOR,

AND MANUFACTURING COMPANY, A CORPORATION OF WESTINGHOUSE ELECTRIC PENNSYLVANIA.

Arr F.

BY MESNE ASSIGNMENTS, TO

AIR PUMP FOR CONDENSERS.

Application filed February 2, 1917. Serial No. 146,135.

T 0 all whom it may concern:

Be it known that I, KARL BAUMANN, a citizen of the Confederation of Switzerland, and a resident of Urmston, in the county of Lancaster, England, have invented a new and useful Improvement in Air Pumps for Condensers, of which the following is a specification.

This invention relates to jet airpumps using water as the operating medium, and especially to pumps of this kind employed in connection with steam condensing plants.

In order to obtain the highest possible vacuum with pumps of the above character, it is necessarythat the water used as the operating medium, commonly termed the sealin water, and contained in a seal tank, shoulcl be maintained at as low a temperature as possible. To do this it has been customary to supply a large amount of cold make up water to the seal tank, or to cool the water in the tank by causing cold water to circulate through tubes placed in the tank.

According to the present invention the sealing water is cooled by evaporating a part thereof by means of a vacuum higher than the vacuum obtaining in the air pump itself. The vacuum for evaporating the seal wateris produced by a steam ejector the steam from which, including the steam evaporated from the seal water and noncondensable gases, is discharged into a suitable part of the main condenser or other point in the plant, for example a suitable stage in the main turbine.

Two constructional forms of the invention are represented diagrammatically by way of example. in the two figures of the accompanying drawings, similar reference numerals being used to indicate like parts in both figures.

In Figure 1 the condenser is shown at 3 and the jet pump for extracting the air and non-condensable gases therefrom at 4, the pump 4 being of the kind using water as the operating medium, of which the well known Leblanc rotary pump is an example. The sealing water for operating the pump is contained in a seal tank 5, from which it is led. into the pump 4 through the pipe 6, the discharge from the pump being connected with the tank 5 by the pipe 7 in the operating the ejector in the steam evaporated from the sealing ing vessel 8 through the pipe 11 may be led into a point between the collecting cone and the diffuser of the pump. Alternatively, however, the water may be. abstracted from the evaporating vessel 8 by a pump and returned into the seal tank 5, as shown for example in Figure 2. A steam ejector 12 fed with steam through the pipe 13 either from the boilers direct or from a stage of the main turbine or engine, or the exhaust of auxiliary engines of the plant or other convenient source, produces the desired degree of vacuum in the evaporating vessel 8. A pipe 14 leads the steam discharged from the ejector 12 into the discharge outlet 15 for the condensate coming from the condenser 3. A weir or weirs 16 is or' are provided in the discharge outlet 15 to ensure eflicient condensation of the steam coming through the pipe 14 from the ejector 12. The condensate is extracted from the discharge outlet 15 by the usual extraction pump indicated at 17 In operation the ejector 12 is designed to maintain a vacuumin the evaporating vessel 8 higher than that obtaining in the air pump 4, so that the sealing water passing through the evaporating evaporated and consequently cooled. The ejector l2 steam issuing therefrom but also the steam evaporated from the sealing water passing through the evaporating vessel 8, will be discharged through the pipe 14 into the condensate discharge outlet 15. The whole of the heat contained in the steam used. for 12, as well as the heat water, will thus be recovered in the condensate which is utilized as feed water for the boilers in the usual way. Any air or noncondensable vapours reaching the evaporating vessel 8 will also be carried by the steam vessel 8 will be is so arranged that not only the from the ejector 12 through the pipe 14 into the condensate discharge outlet 15 from whencethey will pass into the steam space of the condenser 3 and be extracted by the air pump a.

In the arrangement represented in Figure 2 the steam discharged from theej ector 12 in the evaporating vessel 8 is led through the pipe 1 1 into a feed water heater 18 operating at a suitable vacuum. The feed water heater 18 is here shown as being of the surface type but a feed water heater of the jet type may be employed if desired. To obviate the necessity ofproviding a separate air pump for the heater 18 the vapours and non-condensable gases are led away therefrom through a pipe 18 into the condenser 3, from which they are extracted by the air pump 4:- If desired, however, the

pipe 18 may connect the pump 1. r In the arrangement shown in Figure 2 an additional air separating vessel 19 is prowith the air suction of vided into which the water from the seal tank 5 passing throu h the pipe 9 is first led.

The air separating vessel 19 is connected by a pipe 20, as the air pump 4:, but it may be connected to the main condenser 3 or other point under vacuum in the condensing plant, as may be. found, most convenient. ir will be drawn through the pipe 20 from the water passing through the separating vessel 19, the ejector 12 being thus relieved of the additional work of discharging air from the water passing through the evaporating vessel 8. As, in operation, the degree of vacuum obtaining in the air separating vessel 19 will be less than that obtaining in the evaporating vessel 8 the twovessels are connected with one another bya U leg 21 in order to provide a water seal between the two chambers, If such a seal were not provided the ejector 12 would draw air from the air pump 4 without evaporating the water passing through the evaporating vessel 8.

It may be preferable to dispense with the additional air separating vessel 19 because of thegreater simplicity of the apparatus thusv constructed, and particularly when the operating conditions are such that the ejector 12, which at all times maintains a lower absolute pressure within the evaporating vessel 8 thanthat maintained in the vessel 19 by the air pump 4L, can be operated efliciently both to remove the air from and to cause a suflicient evaporation of the water passing through the evaporating vessel 8.

In the arrangement shown in Figure 2 the water is extracted from the evaporating vessel 8 through the pipe 11 by a pump 22 which discharges into the seal tank 5, though it may if desired be allowed to flow into a suitable point under vacuum of. the air pump et'as described with reference to Figure 1.

shown, to a suitable point in vessel 8-will be recovered in the heater 18 and returned in the feed water supplied therefrom to the boilers. 7

With the improved arrangements described above all the steam operating the ejector for producing .the vacuum in the evaporating vessel, as well as the vapour drawn over from the condenser into the air pump and the heat equivalent to the mechanical work required to operate the air pump, is recovered in the form of heat in the condensate.

The amount of makeup water required for the seal tank will be-very small so that pipe connections of small dimensions only are required for the make up water as-well' as for the overflow.

I claim as my invention:

1. A steam condensing plant comprising; asteam condenser and a jetair pump of the kind indicated. and means forcooling the sealing water for the pump by evaporating a part thereof in a vacuum higher than the vacuum obtaining in the air pump itself, said evaporating vacuum being produced by a steam ejector, and means discharging the steam therefrom into a suitable part of the plant operating under vacuum, as described.

2. A condensingplant comprising a steam condenser, a jet air pump communicating therewith, means, including an ejector, for

cooling the sealing water for the pump by 105 evaporating a part thereof in a vacuum higher than the vacuum obtainingin the pump itself, and means for discharging steam from the ejector, and the steam evaporated from the sealing water,

denser. j

3. A'steam condensing plant comprising the combination of'a steam'condenser, ajet air pump communicating with the condenser, a water heater, means, steam ejector, for cooling the sealing water for thepump by evaporating a part thereof in a vacuum higher than the vacuum obtaining in the air pump itself, said evaporating vacuum being produced and means for discharging the steam from the ejector, and the steam evaporatedfromthe sealing water, through the water heater into the condenser.

4:. A steamcondensing plant of the ar- 125 rangement claimed in claim 1 which also comprlses an air separating chamber with a water seal connection to the chamber in substantially into the conincluding a by the steam ejector, 12G

high vacuum in said evaporator, means for delivering steam from said ejector and vapor 15 entrained therewith to said condenser, and means for delivering Water from said evaporator to. a Working passage of said pump.

n testimony whereof I have hereunto subscribed my name this second day of Jan-' 20 nary, 1917.

KARL BAUMANN.

Witnesses W. MoRRIs, F. NIXON.

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