US3081241A

US3081241A - Method and apparatus for introducing hydrogen into a steam atmosphere

Info

Publication number: US3081241A
Application number: US861968A
Authority: US
Inventors: William H Smith
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1959-12-24
Filing date: 1959-12-24
Publication date: 1963-03-12
Anticipated expiration: 1980-03-12

Description

March 12, 1963 w, SMITH METHOD AND APPARATUS FOR INTRODUCING HYDROGEN INTO A STEAM ATMOSPHERE Flled Dec 24, 1959 In venfor Wi/l/am H. Smith His A Home 1/.

METHGD AND APPARATUS FOR HYDROGEN INTQ A STEAMj ATMOSHERE :Wiiliam H. Smith, Burnt Hills, N .Y., assignor to General rosion in a' steam power plant generally tionfwill be better" understoodflwheng taken irfco Electric Company, ii-corporation of New York Filed Dec. 24, 1959,,Ser. No.,86 1,968,. 4- Clairns. (Cl; 204-129) This inventionrelatesto a method ofproviding' hydro- U gen for a steam atmosphere and moreparueunnyone )methOd of "electrolytically decomposingthe' waterin a high pressure high temperature steamgenerating equip- 'ment, such as for example, thetype used in* electrical power generation for the production of hydrogen to'mini An importantproblemwhichjhasbeen" in continual association with high .temperatureflhigh pressuresteam mize corrosion.

generating equipment is that iof corrosion. Corrision of uncoatedmetal parts increases" rapidly with pressuresand temperatures, and in modern steam" generating equipment; for example, inthe range, of 1100 to 1500 F, corrosion is an increasing problem. -In this'andeven higher tempera ture ranges, it has become -the practice to use vari ous materials and metals which will not only Withstand the temperatures but also be relatively uncorrodible or' 3 suitably protected. One of the better metals which has been considered for high temperature'steam atmospheres INTRODUCING quires separate tanks, separate materials, additional hanf dling means and, therefore, the economic. factonalso becomes-increasingly important.. A novel method of introducinghydrogen to a steam boiler is illustrated'in:

3,fi=8l,24i Patented Mar. 12, 1953 ice . v 2 example, aqueous ammonium may be added to the boiler feed water to liberate hydrogen in the boiler. The high pressure supply source requires extra tanks under high pressure and considerable modulating equipmentto con-- trol the amountof gas entering the boiler. Large gas losses are also to be expected in the system through leakage, etc. Since'cost is suchan important problem in steam power generation, the high pressure tank. supply of hydrogen is overshadowed by economic factors. Add

ingmaterials, such as, aqueous ammonia, etc., also re- FIG. 1, by electrolytic decomposition of Water in a boiler.

. Referring now to FIG., 1, there :is schematically shown. an electrolysis system 10 as applied to a steam boiler.

Steam-boiler 11 is shown toincludea bo-ilerwall 12, and water 13 being converted to steam 14. In order to liberatehydrogen by the electrolytic decomposition of water.

in accordance with the teachings of-this invention, a

' suitable cathode 15, for example, platinum, carbon, cuplybdenum. The use of molybdenum,- howeveryin hightempei ature steam generating equipment is limited be}- 5 causeof the formation. of "molybdenum trioxide, due to the exposure of molybdenum, to; oxygen; inthe system, avhich is volatile at high-temperatures wand, therefore,

continual corrosion of molybdenum occurs: The dc signer of high temperature high pressure steam generating equipment is faced with various parameters in steam generating equipment j whichwarrants "the use of metals, j. .folri example, m-olybdenumand tungsten for their high;

trer'igthfarid other high temperature;advantagesfarid, on the other hand,v is, facedv with minimizing corrosion of" these metals at the high temperature conditions by the I 1 useof'suitable coatings-or, reducing atmospheres; g 1

'It is an'objectof'sthis vention to minimizefmetalcon It-is a 'further'objeet of this" inventi to pirovide an impioved method of introduein'g aY reducing gas atmosphere iu steam generating plantsv utilizing tungsten; and molybdenum. I a g v object of; th's; invention to providelgnovel 3 .It s a nas V the eneration j oiler water within Tlieseand other. advantages and features of th' ahydrogen. gas in a" steam, I

plant byi meansof electrolytic decomposition? boiler release hydrogen as. a

per, etc. is positioned within boiler 11 in water 13.

Cathode 15 is electrically connected by means of a suitable connector 16 to" a battery 17 or other source of D.C. current with connector 16 being electrically insulated fromboiler 12'by means of an insulator 19. An insolublea-node 20,'for example,of platinum, carbon etc. is positioned within a chamber Ziand connected to battery 1!! 'by electrical connector 22. Connector 22 is also electrically insulated from chamber 21 by'means of an insu-- 1ator 23. In orderto complete the liquid circuit between isprovided. V

thisinvention depends o-nitheiwell 7 known principle of the electrolytic cell. 7 It is generally known that an} electrical current can be used. 'toproduce hydrogen and oxygen from wa-ter'. by electrolysis; In an '1 electrolytic cell, electrical energy from arr-outside source 3 serves to produce the chemical changes involved, a small part being wasted as heat." Asa, typicalillustratiori'foi the decomposition ofwater, an ,electricalcurrent may ghe passed through water using. insoluble electrodes of} platinum or carbon. TheH ions of the acid willbe.

' the water.

the anode 20 andcathode 15, the chamber 21 iscona 'nected to the boiler by a conduit24. In this manner the level of water 13 in the boiler maintains a corresponding level in chamber 21 and. aboiler watercircuit The operation of attracted b y'the negative plate and-repelled by *theiposi-v tive' plate andithe negative ions will be, attracted {by the positivefland repelledjby the negative plate. Theresult will again be z rdrifting of ionsin both directions through gen is formed'or liberatedat the cathodeoirygen .is beingi continually given of f at the anode; gcThe'invention, there-g Ifore, asgdepictedin 1316, 1 is the "equivalent of an elec; V olytid cell; "While? the'jwater inzia steam power-plant .is'generally; maintaineda't a high purity level,r.-whe1re.the

ter is"lessielectrically.conductive: than desirable suit-r; good" blegadditives maybe. included therein suchgthatj lectr 'stablished betwee Ea-chil iongo neach of the cathodecomk pbinesvwith anelectron there, forming ahydrogen atom; Theseatoms combine into molecules and escape as gas,

volatile at temperatures of 1000 F. and above and thus is a deteriorating feature. Where the supply of oxygen is diminished, M forms on molybdenum and acts as a protective coating. The principle of this invention, therefore, need not be applied to produce hydrogen in sufficient quantities to act as a reducing atmosphere but only to supply a sufficient or predetermined quantity of hydrogen to a normally oxidizing atmosphere to form the protective coating M00 on molybdenum instead of M00 which is highly volatile and deteriorating.

The anode and cathode are not positioned together within the boiler 11 since the decomposition of water will release oxygen into the boiler and minimize the effect to be obtained by the liberation of hydrogen. The provision of the boiler water circuit thereby renders this invention particularly adaptable to enclosed steam power systems, where, due to the fact that oxygen is also liberated, decomposition of boiler water is not contemplated as a means of producing hydrogen. While in the electrolytic cell, oxygen is continually released from the anode, a suitable pressure relief valve 25 is positioned adjacent chamber 21 to be controlled by means well known in the art to maintain the pressure within the system at the desired level. and to release oxygen as it is being formed. Hydrogen liberated at the cathode can enter the steam while oxygen liberated anode can be withdrawn and recovered as a useful by-product.

Where other systems of introducing hydrogen in a steam boiler are employed, the embodiment of this invention may be utilized as a make-up supply or an auxiliary to other and different systems. The electrolytic decomposition of water is more particularly applicable as a make-up means for supplying hydrogen where hydrogen is supplied from other sources and where the quantity desired is high. This system is also applicable to other power generating equipment, for example, nuclear reactors employing the boiling water principle, and the various sizes and power requirements of the cell may be varied to suit particular needs.

It can thus be seen that the objects of my invention are obtained by the use of the electrolysis method to decompose boiler water to form hydrogen in steam power generating equpiment and that such a, method may be used in addition to other present methods. The production of hydrogen limits the formation of volatile M00 on molybdenum. I

While the presentinvention has been described with reference to a particular embodiment, it will be understood'that numerous modifications may be made by those skilled in the art without actually departing from this invention. Therefore, I aim in the appended claims to cover all such equivalent variations as comes within the true spirit and scope of the foregoing disclosure.

What I claim as new. and desire to ecure by, Letters Patent of the United States is: g 1. Steam generating apparatus which comprises a boiler, a water chamber connected to said boiler, a cath ode positioned in and electrically insulated from said boiler for generating hydrogen gas therein, an insoluble anode positioned in and electrically insulated from said Water chamber for generating. oxygen gas therein, a

source of electric current connected to saidv anode and said cathode, and oxygen gas relief means provided for said water chamber and adapted toexclude oxygen gas from said boiler. 1 l 1 2. Steam generating apparatus which comprises a boiler, a water chamber, a conduit connecting said boiler to said water,chamber,"a cathode positionedinwandielcctrically insulated from saidboiler and adapted to generate hydrogen gas therein an insoluble anode positioned in and electrically insulated from said water supply chamher and adapted to generate oxygen gas therein, a source of electric current connected to said anode and said cathode, and oxygen gas relief means provided for said water chamber and adapted to exclude oxygen gas from said boiler.

3. A method of introducing electrolytic hydrogen gas into a steam atmosphere above a steam generating water supply and of introducing electrolytic oxygen gas into an atmosphere above a second water supply which comprises providing a steam generating water supply in a boiler, providing a second water supply in a chamber, providing a third water supply connecting said first Water supply and said second water supply, providing an electrode in said first Water supply, 'insulatingelectrically said electrode from said boiler, decomposing electrolytically a portion of said first water supply whereby only electrolytic hydrogen gas is generated in said first water supply and liberated into said steam atmosphere to limit oxidation of metals exposed to said steam atmosphere, providing an electrode in said chamber, insulating electrically said electrode from said chamber, decomposing electrolytically a portion of said second water supply whereby only electrolytic oxygen gas is generated in said second water supply, and removing said oxygen gas from said second water supply, thereby preventing mixing of said oxygen gas with said hydrogen gas.

4. A method of introducing electrolytic hydrogen gas into a steam atmosphere above a steam generating water supply and of introducing electrolytic oxygen gas into an atmosphere above a second water supply which comprises providing a steam generating water supply in a boiler, providing a second water supply in a chamber and connected to said first water supply, providing an electrode in said first water supply, insulating electrically said electrode from said boiler, decomposiing electrolytically a portion of said first water supply whereby only electrolytic hydrogen gas is generated in said first water supply and liberated into said steam atmosphere to limit oxidation of metals exposed to said steam atmosphere, providing an electrode in said chamber, insulating. electrically said electrode from said chamber, decomposing electrolytically a portion of said second water supply whereby only electrolytic oxygen gas is generated in said second water supply, and removing said oxygen gas from said second water supply, thereby preventing mixing of said oxygen gas with said hydrogen gas.

ReferenccsCited in the file of this patent UNITED STATES PATENTS 736,868 McCarty Aug. 18, 1903 800,296 Harris et al Sept. 26, 1905 1,581,944 Hausmeister Apr. 20, 1926 1,666,523 Bailey Apr. 17, 1928 1,783,726 Lappe et a1. 'Dec. 2, 1930 1,825,477 Reichart Sept. 29, 1931 1,835,425 Pier Dec. 8, 1931 1,912,188 Gann May 30,1933 2,763,611 Breden Sept. 18, 1956 FOREIGN PATENTS 104,856 Germany Mar. 30, 1898 14,818 Great'Britain July 7, 1900 of 1898 154,610 Great Britain Nov. 24, 1921 583,449 Great Britain 7 Dec. 18, 1946 610,725 Great Britain Oct. 20, 1948 ornnn REFERENCES

Claims

3. A METHOD OF INTRODUCING ELECTROLYTIC HYDROGEN GAS INTO A STEAM ATMOSPHERE ABOVE A STEAM GENERATING WATER SUPPLY AND OF INTRODUCING ELECTROLYTIC OXYGEN GAS INTO AN ATMOSPHERE ABOVE A SECOND WATER SUPPLY WHICH COMPRISES, PROVIDING A STEAM GENERATING WATER SUPPLY IN A BOILER, PROVIDING A SECOND WATER SUPPLY IN A CHAMBER, PROVIDING A THIRD WATER SUPPLY CONNECTING SAID FIRST WATER SUPPLY AND SAID SECOND WATER SUPPLY, INSULATING ELECTRICALLY TRODE IN SAID FIRST WATER SUPPLY, INSULATING ELECTRICALLY SAID ELECTRODE FROM SAID BOILER, DECOMPOSING ELECTROLYTICALLY A PORTION OF SAID FIRST WATER SUPPLY WHEREBY ONLY ELECTROLYTIC HYDROGEN GAS IS GENERATED IN SAID FIRST WATER SUPPLY AND LIBERATED INTO SAID STEAM ATMOSPHERE TO LIMIT OXIDATION OF METALS EXPOSED TO SAID STEAM ATMOSPHERE, PROVIDING AN ELECTRODE IN SAID CHAMBER, INSULATING ELECTRICALLY SAID ELECTRODE FROM SAID CHAMBER, DECOMPOSING ELECTROLYTICALLY A PORTION OF SAID SECOND WATER SUPPLY WHEREBY ONLY ELECTROLYTIC OXYGEN GAS IS GENERATED IN SAID SECOND WATER SUPPLY, AND REMOVING SAID OXYGEN GAS FROM SAID SECOND WATER SUPPLY, THEREBY PREVENTING MIXING OF SAID OXYGEN GAS WITH SAID HYDROGEN GAS.