Патент USA US2130626код для вставки
Sept. 20, 1938. H. E. KAISER 2,130,626 PROCESS FOR QUENCHING PORTLAND CEMENT CLINKERS ' ‘ Filed Sept 20, 193-7 [1'2 venfor: H rry Z’. Kaiser. ?ii'arnely. 2,130,626 Patented (Sept. 20, 1938v ~ UNITED STATES PATENT ._-OFFlCE " 23130526 . v raocsss For. QUENCHING PORTLAND CLINKEB Harry a. mm‘, are... + 1 , REISSUED Nov 2 6 1940 ' assixnor to Cali ‘ fornia Portland Cement Company, Los Angeles, CaliL, a corporation of California v Application September 20, ‘1937, Serial No.1164,61“‘ ' 10 Claims. (01. 263-53?) This invention relates generally to the manu facture of Portland cement, and has to do par ticularly with an improved process for rapidly quenching Portland cement clinker by means of 5 another Portland cement clinker that is ?nely divided and‘ admixed with the clinker undergo ing quenching, under conditions that effect rapid and uniform cooling of the latter. It‘has come to be recognized that very de?nite 10 advantages, from a number of standpoints, re sult from quenching, i. e. very rapid cooling, of Portland cement clinker. Theoretically, one ob ject of rapid quenching of the clinker while it is at substantially the clinker forming tempera 15 ture, is to “freeze" the equilibrium which has ‘ been set up at the clinkering temperatures among the various compounds in vthe clinker. Accord ingly, it is desirable to quench the clinker im- - ' proper quenching e?ect. I have obtained very satisfactory results by admixing with one part of the hot clinker, around three parts by weight of the quenching clinker of a ?neness passing a ' quarter-inch mesh screen. As indicated, these relative proportions of the admixed hot and, quenching clinker may vary in accordance with other factors, as for example the temperature differential between the two materials in a given instance‘. In this connection itlmay be observed 10' that the quenching clinker may be cold, or it may be slightly heated to atemperature under say 300° F. As a general rule the proportion of quenching clinker-in the admixture will be sub stantially in excess of the hot clinker undergoing 15 quenching. ‘ . For the purpose of facilitating the desired ra pidity and uniformity 'of quenching, the hot clinker and quenching clinker may be rapidly mediately or very shortly after it passes from and intimately admixed in any suitable manner 20 20 the clinkering zone of the kiln. It will sui?ce within a cooling zone, for example in an elongated to state, without entering into a speci?c discus- ‘ sion of the individual compounds or their inter relationship and effects under equilibrium con ditions, that it hasbecome recognized that by 25 maintaining or freezing that equilibrium by rapid cylinder that is rotated to give continuous mixing agitation. The admixture is maintained in the cooling zone fora period of time‘ required to drop the clinker temperature through the proper quenching-range. Various ‘factors may‘ enter into quenching, certain properties of the clinker itself, _ the time element, but it may be stated, as illus and of the ?nished cement, are de?nitely im trative, that ordinarily it will be desirable to cool proved. ~ the clinker from a temperature that may range A, number of apparent advantages result from from well above 1800° vF. to ashigh as 2600° F., 30 30 rapid quenching of Portland cement clinker. to a temperature under 7 00° F., within a period of ' Quenching appears to promote ease of grinda bility, as indicated by-the fact that the quenched clinker will be reduced to a ?ner state of divi ‘sion when subjected to a given grinding opera 35 tion‘, than a normally cooled or quenched clinker ground under the, same conditions. It is also indi cated that the resultant clinker will have less tendency to “dust." ' Tests indicate that cementi tidus or concrete mixtures containing cement 40 made from the quenched clinker, show a mate‘ rially lowered degree of expansion under the . standardmethods of determination. In ‘accordance with the invention, the hot clinker is admixed with ‘a ?nely divided and 45 relatively cool Portland cement clinker (herein after referred to asthe quenching clinker), pref erably immediately after the hot clinker leaves the clinkering zone of the kiln, in order that the. ?ve minutes. After the hot clinker has ‘become quenched,»the quenching- clinker is then sep arated therefrom in one or more separating 'or screening stages su?icient to free the quenched 35 clinker from the quenching clinker.’ Absolute and complete separation may not be essential, particularly where the two clinkers have similar 7 composition and properties, and in any event a small percentage of quenching clinker ?nes re 40 maining in the quenched clinker will be unobjec tionable. The quenched clinker may then be ground or processed by any of the usual methods ' ‘of producing Portland cement. The separated ’ quenching ‘clinker however, having become su?i- ' 45 ciently'f cooled before separation from the quenched clinker, or afterward, is again used as a quenching medium for "subsequently formed clinker. In this manner, the same quantity of “freezing” effect of quenching may be had upon > quenching clinker may be recirculated repeatedly 50 50 the hot clinker while it is still as close as possible as a quenching medium for a continuously ?ow to the kiln temperature. If desired the quench ing stream of hot Portland cement clinker. ing clinker may be introduced into the nose of the Perhaps the foregoing description of the proc kiln itself. Any suitable quantity'or proportion ess can be ampli?ed to advantage by reference to of the quenching clinker may be admixed with a typical and illustrative system for carrying out the hot clinker that will produce the desired and a 2,130,626 , " the invention, as shown diagrammatically and in Portland'cement clinker by admixing relatively‘ ?ow sheet form in the accompanying drawing. » cool Portland cement clinker with the hot clinker, Portland cement clinker formed in the clinker maintaining the clinkers in intimate contact - ing kiln I 0 is delivered by suitable means, con while the hot clinker cools, and separating added ventionally illustrated by chute ll, into the up- clinker from the quenched clinker. per end of an elongated cylindn'c cooler l2 that 5. The process that includes, quenching hot preferably is slowly rotated by suitable means, Portland cement clinker by admixing relatively not shown’. The ?nely divided quenching clinker cool quenching Portland cement clinker with the may be fed from a conveyor line l3 through line " 10 ll to be admixed with the hot clinker at the‘inlet hot clinker, maintaining the clinkers in intimate contact‘ while the hot clinker cools, separating .end of chute II and directly ‘after the clinker quenching clinker ‘from the quenched clinker, and 10 leaves the kiln, for the quenching clinker may be admixing the separated quenching clinker with taken via line I5 and fed into the inlet end |2a subsequently produced hot Portland ‘cement of the cooling' chamber. Asillustrated, the feed ._ clinker to quench same. ~ end of the chamber may contain a suitablere 6. The process that includes, quenching a con 15 fractory lining [6. The two clinkers are- rapidly tinuously stream of hot Portland cement brought into intimate contact and subjected to clinker by?owing continuously to and intimately thorough admixture within the rotatingcooler admixing with the hot adding clinker a relatively ?ne l2. The admixture will remain in the cooler forv and cool Portland ‘cement clinker, maintaining 20 a period of time required to quench the clinker the clinkers in contact while the hot clinker' 20 through the proper temperature range, and ordi cools, and then continuously separating added narily a time period of around ?ve to ten minutes clinker from the quenched clinker. will su?ice where a ratio of substantially three 7. The process that includes, quenching a con parts of quenching clinker to one part of thehot tinuously ?owing stream of hot Portland cement clinker is used. ' ' ‘clinker by continuously adding to and intimately The admixture may be subjected to further admixing with the hot clinker a relatively ?ne cooling and further agitation to completely sep and cool quenching Portland cement clinker, arate the quenching clinker from the quenched maintaining the clinkers in contact whilethe clinker, in a second cooler ll into whichthe ma 30 terial is'fed from the discharge end of cooler hot clinker cools, then continuously separating quenching clinker from the quenched clinker, I2 via line [8. Cooler I ‘I may have one or more and continuously returning/and adding separated screen sections l9 through which the freed and ' relatively ?ne quenching clinker particles will - quenching clinker to the hot clinker stream. 8. The process that includes, continuously pass a stream of hot Portland cement clinker from bin 2|. As illustrated, the separated quenching ' ing a clinkering zone, then quenching the hot clinker pass into a hopper 20 and thence into a storage clinkerwill be continuously taken from bin 2| by way of conveyor line B to be returned for ad mixture with the hot clinker being discharged from the ' clinker .kiln. Separated quenched clinker is discharged from cooler ll into storage bin 22. During the quenching and cooling stages, particles of the quenched clinker reduced to‘ a ?neness enabling them to pass through the screen 45 » l9, may become separated out with the quench~ ing clinker, resulting in an increase in the quan- _ ' tity of clinker being discharged into bin 2 I. Any excess over 'the amount of quenching clinker re quired for installation, may be combined with the quenched clinker in storage 22, as by providing anv over?ow ledge‘ at 23 between the two bins. I claim: by immediately a d continuously introducing to and intimately ‘a xing- with the hot clinker stream a relatively ?nely divided and 0601 Port land cement clinker, and passing the mixture through a cooling zone.. 9. The .process that includes, continuously pass ing a stream of hot Portland cement clinker from ‘a clinkering ‘zone, then‘ quenching the hot clinker by immediately and continuously introducing to and intimately admixing with the hot clinker 45 stream a relatively ?nely divided and cool Port land cement quenching clinker, passing the mix ture through a cooling zone, and then continu ously separating the quenching clinker from ‘the quenched clinker. } 10. The process that includes, continuously passing a stream ofhot Portland cement‘ clinker from a. clinkering zone, then quenching the hot 1. The process that includes, ‘quenching ‘hot Portland cement clinker by admixing relatively cool‘ Portland cement clinker with the hot clinker. ‘clinker-by immediately and continuously intro 2. The process that includes, quenching hot ducing to and intimately admixing with the hot Portlandcement clinker by admixing relatively clinker a relatively ?nely divided and cool cool and ?nely divided Portland cement clinker Portlandstream cement quenching clinker,‘ _ g- the with the hot clinker. , ' ‘ through a coolingvv zone, then continu ,3. 'Ihe process vthat includes, quenching hot mixture ously separating added quenching clinker from Portland cement clinker by admixing relatively the quenched clinker, and continuously return; cool and ?nely divided Portland cement clinker ing and adding separated quenching clinker to withthe hot clinker, and agitating the mixture while the hot clinker‘ cools. ' 4.,/The' process thatl includes, quenching hot. the hot clinker stream. ' ‘HARRY E. KAISER.