US2108610A - Operation of regenerative ovens - Google Patents

Description

C. OTTO OPERATION OF REGENERATIVE OVENS Feb. 15, 19,38.

F'ild July 28, 1936 2 Sheets-Sheet l INVENTOR adw zb- 8% ATTORNEY F 15, 1938. c. OTTO OPERATION OF REGENERATIVE OVENS Filed July 28, 1936 2 Sheets-Sheet 2 Fig. 5

Fig. 4

INVENTOR 5 ATTORNEY ovens adapted to be heated Patented Feb. 15, 1938 PATENT OFFICE 2,108,610 OPERATION OF REGENERATIVE OVENS Carl Otto, Essen, Germany Application July 28, 1936, Serial No.

In Germany May 17, 1935 3 Claims.

The present invention relates to industrial by rich gas and provided with means for pre-heating the air of combustion by regenerators, in particular under- 'fired ovens.

In rich gas-heated ovens in which the air of combustion is pre-heated by means of regenerators frequently explosions occur if the place where the rich gas is shut on and the place yvhere the gas is exist between these two places, which explosions are due to the feature that the air entering said spaces or intentionally supplied to them for degraphitizing purposes, is'mixed therein with the remainder of'the rich gas so as to form an explosive mixture. In order to obviate this drawback and to remove upon reversal of the draught the unburned gas remainder from the shut-off gas distributing pipes of regenerative ovens intended for the production of gas and coke, one

has already 'connected the gas distributing pipes 7 after the gas feed has been shut off, that is, while they communicate in known manner with the outer air, to the waste heat flue fora short period of time, say one minute, by special connecting pipes fitted with valves. In this way the rich gas still existing in the space between the shutoff valve and the burning place is sucked into the waste heat flue by the pressure below atmospheric prevailing in this flue.

This mode of operation, however, suffers from the drawback that unburned rich gas arrives in the waste heat flue where, if the waste gases con tain air, it may cause explosions. In addition, a rather large quantityof rich gas gets lost thereby. I The invention has now for its object to obviate this drawback which object is achieved by inert gases being blown for some time into the rich.

gas feed pipes, after the gas feed has been shut off. This operation may take place immediately before the commencement of the gas feed. Inert gases suited for this purpose are for example the waste gases of the oven or steam. The period of time required for blowing-in the inert gas is short when compared with the total duration of the regeneration, it may amount to about one minute.

In. order that the invention may be clearly understood and readily carried into effect, a preferred embodiment of the means for blowing-in the inert gas is illustrated by way of example in the accompanying drawings as applied to an underfired coke oven. Inthese drawings Figure 1 shows part of the arched foundation burned are far distant from oneanother and spaces of larger cross sectional area 'izontal rich gas distributing The three way cocks g of the oven with the lower portion of the regenerator spaces, and is a section on line 1-1 of'Figure 2,

Figure 2 is a vertical section on line 11-11 of Figure 1 the right hand portion of the figure being seen from the left of said line, and the left hand portion of the figure being seen from the right of said line,

Figure 3 is an elevation of the oven parts situated below the section line III-III of Figure 2,

Figure 4 is a detail of Figure 1 in a somewhat modified form and on larger scale, and

Figure 5 shows the same details in a view corresponding to Figure 2.

In the underflred oven illustrated in these figures the stack flue a communicates with a suction blower b driven by a motor 0 which is started by the reversing winch (by any suitable way cocks g, pipes p, and the rich gas valves h, which likewise are three way cocks, into the horizontal rich gas distributing branches m. The rich gas is supplied through a channel It and the ascending pipes 0 through each two rich gas valves h either the upper or lower of which is opened in every regeneration period, into the'hormains m from which vertical pipes 12 are branched off. The oven illustrated is constructed with hair-pin flues, so that the even-numbered pipes n are connected to one main m and the odd-numbered pipes to the other main The valves h thus communicate with the ascending pipes o as well as with a main m and with the pipes 12. The three way cock 9 communicates with the pipes 12 and with the waste heat distributing pipe I and have further each an inlet port q for the degraphitizing air.

Upon reversal of the flow the following operations take place: First the blower b is actuated to establish, and thereafter to maintain, a certain pressure in the waste heat distributing pipe f. are then turned over so as to connect the pipes p withthe distributing pipe f. Next each of the cocks h which till now has fed the rich gas is turned degrees so that waste heat from the waste heat distributing pipe 1 flows into the main-m,till now filled with rich gas, and into the rich gas branches n connected thereto, the waste heat pushing away the rich gas still exheating flues. Simultaneously also waste heat passes through the other valve h of the same pair of valves into the main m which did not lead gas during the preceding regeneration period and pushes out the'air previously held in the last mentioned pipes m and their branches n. The battery waste heat valves are turned over whereby the direction of flow in the heating. flues is changed. Thereuponthe main m till now not fed with gas is adjusted to gas feed by turning over the respective valve h, whereby the next regeneration period is started. The time elapsing between turning over' the two rich gas valves It will in general be sumcient to push away by the following waste heat the gas still present in the distributing pipes. Therefore, simultaneously with the initiation of the new regeneration period,-the appropriate three way cocks y can be turned into the positions in which their air inlet ports q are open for the passage of degraphitizing air into the rich gas mains m'which are not then feeding rich gas. Degraphitizing air may thus be supplied during the first section thereof,

for example for 10 minutes, with a total duration of the regeneration period of 30 minutes.

In the modification illustrated in Figures 4 and 5 the three way cook a is ,replaced by a simple shut-off valve 1' which in general is permanently open and is closed only when the heating wall situated above the respective pipe 17 is to be put out of operation. In this arrangement further the pipes p have trumpet-like enlarged ends 3 which open at a'certain distance apart from the air ports of the rich gas valves h. The: arrangement of the suction blower b and of the remaining members serving to blow-in the waste heat may be the same as in the first embodiment. The waste gases are pressed into the pipes i also in this embodiment from the beginning of the reversal or shortly before and up till the re-- versal is terminated. The trumpet ends s facing the air ports t are soshaped and the pressure prevailing in the distributing pipe I is so selected,

that only waste gas enters the air ports ofthe valves h and pushes away the remainders of rich gas still present in the gas main m previously fed with gas.

What I claim and desire to secure by Letters Patent is:-

1. In the operation of a regeneratiVe furnace comprising a connection operable to'alternately supply rich fuel gas and degraphitizing air during successive regeneration periods, the method which consists in passing an inert gas-through said connection during intervals prior to and following the passage of degraphitizing air through said connection.

2. In the operation of a regenerative oven furnace having two sets of rich fuel gas supply connections, each set supplying rich fuel gas during periods alternating with periods in which rich fuel gas is supplied by the other set, the method which consists in passing inert gas, degraphitizing air and inert gas successively through said supply connections during a period in which the connections are notsupplying fuel gas.

3. In the operation of a regenerative coke oven battery having a stack flue drawing waste 7 gases away from the battery and having two .sets

of rich fuel gas supply connections, each connection adapted to have its inlet portion opened to the atmosphere, each set supplying rich fuel gasduring periods alternating with the periods in which rich fuel gas is supplied by the other set, the method which consists in opening the inlet portionof each supply connection to the atmosphere so that atmospheric air may be drawn through the connection during periods alternating with periods in which rich fuel gas is supplied through said connection, and compressing waste gases withdrawn from the battery and passing a portion of said gases through each connection during a brief period intervening between each period during which rich fuel gas is supplied through said connection and the immediately following and immediately preceding periods during which the inlet portion of the connection is open to the atmosphere, whereby waste gases, degraphitizing air and waste gases are passed successively through each connection during each period in which said connection is not supplying fuel gas.

CARL O'I'I'O.

Images