US1733307A - Coking process - Google Patents

Description

Patented Oct. 29, 1929 V NITED S'IZATES PATENT 0mm VELOPMENT CORPORACEION, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION or rnnns rvalvm COKING PROCESS no Drawing. Application med July 5,1921, Serial No. 482,615, and in Germany December 28, 1917. Renewed March 12, 1925.

(GRANTED THE PROVISIONS OF THE ACT OF 3, I321, 41 STATTL, 1313i Thisinvention relates in general to the art of making coke, particularly in by-product coke-ovens, and more particularly to a method of shortening the time required in coking carbonaceous material in regenerative coke ovens.

Importantobjects of the invention are the production of uniform high grade coke, suitable for metallurgical, domestic and other uses, in a shorter coking time than has heretofore been attained; an increase in ammonia yield; the production of coke for blast furnace use that is free burning and such other objects and advantages of the invention as are found to obtain in the-process hereinafter set forth and claimed.

' According to my U. S? Letters Patent #1369573 dated February 22, 1921, the time required for the complete carbonizing in the coking of fuels, particularly in chamber ovens, is shortened by vapors being introduced after the period for the average carbonizing, which do away both with the local superheatings just beginning and the still. existing uncarbonized places, this being eiiected by shutting off the distillingchamber against the gas collecting pipe and introducing steam by itself in the opposite directiofi to the previous flow of gas, that is into the chamber from above, and sucking it ofli' downward. In so far as an increase in the yield of ammqnia takes place inthis connec-' be ascribed to the protection of the ammonia against secondary decomposition in consequence of the dilution by the water vapor and the simultaneou washing away by-the same. I

My aforesaid Patent 1,369,673 s ows and describes (at lines 59 to 103 of its page 1) a coking chamber of an oven battery,-said coking chamber being one of a plurality of coking chambers elongated transversely with respect to the battery and disposed in alterna tion with transversely-elongated heatingwalls provided with-the usual flame flues for supplying heat to coke the charges within such coking chambers. And said patent further states'that it will, of course, be understood that the ovens shown in the drawings may be fired with their own gas or other gas by developing the coking heat extraneously of the charge, and not by combustion within the coking chambers as in bee-hive practice; and

- through which the distillates are conveyed for subsequent treatment in by-product recovery apparatus. The flow. through the individual ascension pipes into the collecting main is controlled by means of valves. oven chamber is closed on its opposite sides Each coke.

HEINRICH norrnns, or Essen-none, GERMANY, assrenon 'ro THE K'OPPERS- .DE-.

by coke oven doors, which are removed-when the coke is ready for pushing. The charge of coal introduced into the coking chamber is leveled by means of a leveling device inserted through a leveling hole on one side of the oven battery and normally closed by a' closure element.

\ According to my present invention, a 7

further shortening of the carbonizing period, with a simultaneous increase in the primary ammonia production, is to be accomplished by conducting steam .and air in repeated alternation over the glowingoven charge, in-

stead of steam alone. Thepassage of air over the glowing coke efiects a partial combustion of the coke while, 'from the very first, a distribution of the heat produced takes place, which, through the subsequentpassin over'of steam or alsoof an inert gas, is turne into a perfect equalization of heat. By reason of this increased heat development on the one hand and the di ectly following distribution of this additio al heat also throughout the entire coke cake, the carbonizing period can be still further shortened since it is now possible mam With the passing over of thesetwo materials at a correspondingly earlier moment than is the case according to the said patent, that is, at a temperature of approximately from 700 to 800 degrees centigrade.

The passing over of air and the combustion process thus initiated also influences the pri- 5 mary ammonia production in so far as, ac-

cording to experiment made, when passing water in the form of steam over-the glowing coke, a part of the coke nitrogen is converted into ammonia when just previously combustion by oxygen had taken place. In coking, as a rule, only the ammonia is developed which is released in the distillation, so that the development of ammonia is really finished -when the coal is transformed into coke; the 5 rest of the nitrogen stays back in the coke 'as so-called coke-fixed nitrogen. It is seen that the origin of ammonia when wetting the glowing coke cake as it comes from the and air thereover in alternation in opposite directions. a

HEINRICH; KOPPERS.

oven is also attributable to this fact, since here, too, the coke cake has been exposed to the air for a certain length of time and has thus experienced a partial combustion; on this there have also been built processes for obtaining this ammonia which develops when the coke is wetted. This process can be explained or accounted for by the fact that the temporarily occurring oxidation exposes the coke nitrogen combinations, so'that these are more easily converted into ammonia by sub-' sequent treatment with water in the form of steam.

What is claimed is- 1 1. A process of coking fuels in a coking retort oven consisting in subjecting the charge to extr'aneously developed coking heat and after the distillation of the charge has been in great part completed, and during the continuance of the coking, then passing air and steam over the coking charge in alternation. 2. A process of coking fuels consisting in subjecting the charge to extraneously developed coking heat and after the charge has attained a temperature of 700 to 800 de grees centigrade, and during the continuance of the coking, then passing air and steam over the cokin charge in alternation.

3. In t e coking of fuels, a process for hastening the carbonization of the charge and for increasing the ammonia yield, which consistsin applying an extraneously developed .coking heat to the charge and after the distillation of the charge has been in great part completed, and during the continuance of the coking, then passing steam and air alternately over the glowing coke in the oven.

43. In the coking of fuels, a process for hastening the carbonization of the charge and increasing the ammonia yield, which consists in applying an extraneously developed coking heat to the charge and after the distillation of the charge has been in great part completed, and during the continuance of the coking, then passing steam and air alternately in opposite directions over the glowing coke-in the oven.