US2746913A - Rich gas nozzle for regenerative coke oven with recirculation heating - Google Patents

Description

May 22, 1956 H. scHURl-IOFF RICH GAS NOZZLE FOR REGENERATIVE COKE OVEN WITH RECIRCULATION HEATING Filed Sept.

//////&////// W RICH GAS NOZZLE FR REGENERATIVE COKE OVEN WITH RECRCULATION HEATING Heinrich Schiirhoif, Essen-Stadtwald, Germany, assignor,

by mesne assignments, to Kappers Company, Inc., Pittsburgh, Pa., a corporation of Delaware Application September 1, 1954, Serial No. 453,517

3 claims. (cl. 2oz-139) The present invention relates to a regenerative coke oven with vertical heating ues and rich gas nozzles projecting up from the heating line soles to which the rich gas is admitted with a partial amount of the air for the combustion.

It is known to mix rich gas with preheated air before admission of the gas into the heating ues by admitting the air to the gas underneath the heating ue soles, in order to prevent a pyrogeneous decomposition of the gas admitted at various levels in the heating flues and to obtain an elongated llame. For this, the heating ues are provided along the greater part of their height with ceramic pipes provided with outlet openings for the gasair mixture, whereby the main amount of air for combustion of the total gas is admitted to the heating flue soles independently of these pipes. This arrangement of the ceramic pipes in the heating tlues requires, however, a considerable amount of space and an additional expenditure which is out of proportion to the eiect attained. Furthermore, they prevent, in the case of gas distribution channels of the gas gun type, horizontally arranged in the brickwork underneath the heating flues, the possibility of regulating the amounts of heating gas and decarbonizing and diluting air admitted through the rich gas nozzles to each heating ilue.

It is further known, in order to obtain in the heating tlues a uniform higher level heating, to supply exchangeable free-standing rich gas nozzles projecting into the flues at various levels above their soles. In such coke ovens, if the heating is effected with gas rich in hydrocarbon content, a pyrogeneous decomposition takes place in the free-standing rich gas nozzles projecting in the heating ues which clogs the nozzles and requires a constant cleaning operation which is possible only by replacement from the flues.

It is in fact also customary to flow air through the rich gas lines through which rich gas is not then flowing in order to burn the graphite previously deposited in the lines or also continuously to add air to the rich gas outside of the oven. However, in this case there is the danger that, especially on heating with hydrocarbon-rich gas, when too little air is added, it is not sufiicient in order to avoid the pyrogeneous decomposition in the free-standing rich gas nozzles projecting in the heating flues, and when rather large amounts of air are added, explosive mixtures form in the heating iiues. The addition of large amounts of cold air has the further disadvantage of being uneconomic, since the latter does not take part in the heat exchange in the regenerators.

The present invention relates to the provision in the heating ues of open top free-standing extensions for the rich gas nozzles which are detachable therefrom and have suction slots in the lower part above the outlets from the rich gas nozzles through which slots is drawn a part of the combustion air owing into the heating ues from separate air inlets, such as air regenerator ports, in the heating flue soles. It is thereby possible to obtain a uniform, regulable high heating while preventing a pyrogeneous decomposition of the hydrocarbons in the freestanding extensions for the rich gas nozzles in the heating fiues and without the formation of explosive mixtures. Furthermore, the thus-constructed extensions for the nozzles can serve in known manner for regulating the elevation of admission of the gas for high heating as well as the amount of gas.

The extensions for the rich gas nozzles, constructed for this purpose as attachments, and standing free on the heating tue soles, can be changed through the usual access openings in the oven roof and also can be installed in present coke ovens during operation on the calibrated rich gas nozzles in situ on each of the heating liue soles from the oven roof. These nozzle attachments can also be provided above or below with calibrated nozzles or orices, or can have an invariable cross section which regulates the velocity and amounts.

Thereby, the admission into the flues of exactly desired amounts of gas mixed with drawn in air or waste combustion gas products at the dilferent level places, necessary for uniform higher level heating, is determinable.

The nozzle attachments of the present invention can be used in coke ovens of any type, for example, in the so-called recirculation ovens of the Kelting patent, that is, such ovens in which the vertical heating ues are connected at the top and bottom in pairs in such manner that waste gas combustion products recirculates through them.

In order to attain an elongated flame combustion when heating with rich gas, the admixing of waste gas gradually along the height as heretofore done is not suicient to avoid overheating at the heating flue soles when heating with rich gas high in hydrocarbon content.

In regenerative coke ovens with said recirculation heating, it has also been suggested,l in such cases where necessary for construction reasons, to place the rich gas nozzles in the vertical middle plane of the heating wall whereby the rich gas nozzle is located between the regenerator air port and the recirculation orifice and the rich gas nozzle is allowed to project only slightly above the upper edge of the recirculation orifice. This should be avoided, since the rich gas is flowed (deflected) directly into the path of the air from the regenerator air ports by the waste gas stream leaving the recirculation orifice and the mixing of the waste gas with the rich gas is more or less inefficient.

The invention is illustrated in preferred embodiment in the accompanying drawings.

Fig. l is a partial longitudinal section through the heating flues of a heating wall, taken crosswise of a battery of coking chambers of the horizontal gas gun type.

Fig. 2 shows the lower part of a pair of the heating flues in enlarged scale of another embodiment of the invention with underjet ducts.

The heating flues serving to heat the oven chambers alongside the same but not shown in the drawing are connected in pairs as twin flues il, 2, wherein the pair of twin Hues are separated from one another by a vertical wall 3, and the ilues of each pair are separated by a wall 3.

In the heating flue soles d there are arranged horizontal rich gas conduits 5 of the gas gun type from which vertical ducts 6 branch off, and which separately discharge through upper ports into the heating flues 1, 2 on both sides of a lower recirculation orifice 7 in the intermediate wall 3. On the ports of the vertical ducts 6 there are placed the usual removable calibrated rich gas nozzles 8, the cross section of which are respectively calibrated for adding various amounts of heating gas corresponding to the different amounts as required in each heating Hue along the length of the oven.

On these rich gas nozzles 8 are removably mounted i Patented May 22,l 195.6

tubular, ceramic attachments 9 which have longitudinal slots 10 in their lower part. The attachments 9 termif nate at their open tops at about the height of the upper end 1l of the recirculation orice 7 or slightly thereabove.

In the embodiment shown in Fig. 1, the rich gas nozzles are placed with the attachments 9 directly on both sides of the recirculation orifice 7, and between the regenerator air duct 12, and its port and recirculation orifice 7. Such an arrangement of the rich gas nozzles can be considered when the latter must be placed in a vertical middle plane of the heating wall, as for example in the case of the horizontal gas gun type of ovens, wherein the horizontal rich gas conduits 5 are charged from distributing lines 19 at the sides oi" the battery rather than from accessible foundation passageways.

Through the suction slots in the attachments 9, there is drawn waste gas that enters from the recirculated orifice 7 into the upwardly burning heating flue 1 or 2, which operates in alternation, and also a part of the combustion air from the regenerators 2t), as the air leaves the upper ports of the regenerator air ducts 12 so that, as a result of this mixing with the rich gas, a pyrogeneous decomposition of the same can not take place in attachments 9. An initial combustion can begin above the nozzie 9 as a result of the partial mixing with air from air duct 12 which takes place here, whereupon this combustion is delayed by the addition of waste gas recirculated from the top of the heating flue through orifice 7. The waste gas reaches in part around the rich gas nozzle attachments 9 between the air leaving the air ducts 12 and the gas leaving the nozzles 9, whereby the flow of gas and air together along the height of the heating flue takes place only gradually.

In the moditication shown in Fig. 2 the nozzles 9 and the air ducts 12 are placed together in the same plane crosswise of the heating wall before the recirculation orifice 7, so that waste gas leaving orifice 7 can pass directly between gas and air.

The waste gas of the llame burning upwardly in each of the heating ues 1 yarrive through the upper connecting orilices 14 in a heating ue 2, from the bottom of which ilue 2, it is drawn through ducts 12, into the regenerators 20, the waste gas leaving the battery through sole channels 22, and ducts 25, which discharge to a stack tiue not shown. After operating a valve system 21 for reversing the direction of heating, the heating takes place by upward combustion in heating ue 2 and downflow of waste gas in flue 1.

The nozzles 9 can be installed and replaced through the conventional access openings 16 in the oven roof 15.

They can be installed in present plants during operation and if necessary can be placedY at such greater or lower heights in each tine as necessary.

I claim:

1. A regenerative coke oven having vertical heating ues, air regenerator ports and rich gas ports in the soles of the heating ilues for introducing combustion air and rich gas into the bottoms of the ues, and free-standing rich gas nozzles projecting up from the rich gas ports at the soles of the heating lines and terminating at their upper parts in upper gas outlets to the ues, said nozzles comprising free-standing removably mounted hollow elements having suction slots at the lower part thereof which open to the bottom of the tlues above the rich gas ports but below the upper gas outlets of the rich gas nozzle elements to the ilues.

2. A regenerative coke oven having vertical heating iiues which are connected with one another at the top and bottom in such manner that waste gas recirculates therethrough, and with air regenerator ports and rich gas ports inthe soles of the ues for introducing cornbustion air and'rich gas into the bottoms of the iiues and rich gas nozzles projecting up from the rich gas ports above the heating ue soles and terminating at their upper parts inI upper gas outlets to the tlues, said nozzles each comprising a lower nozzle seated in its rich gas port and having an upper gas outlet, with a free-standing upward, hollow extension detachably mounted on the lower nozzle and open at the top to the flue, with suction slots below the top of the extension and open to the tlues above the upper gas outlet of the lower nozzle.

3. Coke oven according to claim 2 in which the upward extensions of the lower nozzles consist of attachments removable from the lower nozzles, when the latter are seated in the rich gas ports in the soles of the heating ues, through access passages in the oven roof in alignmentwith the ues.

References Cited inthe le of this patent UNITED STATES PATENTS 390,055 Bell Sept. 25, 1888 509,710 Williamson et al Nov. 28, 1893 909,711 Thompson lan. 12, 1909 1,478,570 Kees Dec. 25, 1923 1,726,494 Ketting z Aug. 27, 1929 1,748,187 Ott Feb. 25, 1930 1,993,574 Totzek Mar. 5, 1935 2,132,522 Van Ackeren Oct. 11, 1938 2,255,406 Becker Sept. 9, 1941 2,569,514 Burklin Oct. 2, 1951

Claims (1)

1. 2. A REGENERATIVE COKE OVEN HAVING VERTICAL HEATING FLUES WHICH ARE CONNECTED WITH ONE ANOTHER AT THE TOP AND BOTTOM IN SUCH MANNER THAT WASTE GAS RECIRCULATES THERETHROUGH, AND WITH AIR REGENERATOR PORTS AND RICH GAS PORTS IN THE SOLES OF THE FLUES FOR INTRODUCING COMBUSTION AIR AND RICH GAS INTO THE BOTTOMS OF THE FLUES AND RICH GAS NOZZLES PROJECTING UP FROM THE RICH GAS PORTS ABOVE THE HEATING FLUE SOLES AND TERMINATING AT THEIR UPPER PARTS IN UPPER GAS OUTLETS TO THE FLUES, SAID NOZZLES EACH COMPRISING A LOWER NOZZLE SEATED IN ITS RICH GAS PORT AND HAVING AN UPPER GAS OUTLET, WITH A FREE-STANDING UPWARD, HOLLOW EXTENSION DETACHABLY MOUNTED ON THE LOWER NOZZLE AND OPEN AT THE TOP TO THE FLUE, WITH SUCTION SLOTS BELOW THE TOP OF THE EXTENSION AND OPEN TO THE FLUES ABOVE THE UPPER GAS OUTLET OF THE LOWER NOZZLE.

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