Show ADVANCE IN L IN MAKING COKE COK by EDWARD W PARKER of the U S geological survey the coke industry in the united states has now reached in good years the mark and moreover there is a steadily growing increase in the proportion of coke made in product byproduct by and retort ovens whereby the valuable products byproducts by of gas tar ammonia etc are saved to the value of tens of millions of dollars annually where the coke is made in the old fashioned beehive bee hive coke ovens all these valuable products byproducts by are entirely wasted in 1912 the total production of coke was short tons valued at an increase of tons in quantity and of in value over 1911 in 1912 the production of beehive coke increased tons or 18 per cent while that of the retort coke increased tons or 49 per cent although larger than in 1911 the output of beehive coke in 1912 did not reach the record figures for 1910 whereas the production of product byproduct by coke in 1912 was by far the largest yet reached in any one year the progress in the construction of retort or product byproduct by ovens as shown by these figures has been the most significant feature of the coke making industry during the last few years the number number of retort ovens in operation increased from in 1911 to in 1912 a gain of whereas the total number of all ovens decreased from to indicating that there were 2236 fewer beehive ovens in existence in 1912 than in 1911 some new ovens of the beehive type were built in 1912 but the number abandoned exceeded the new ones by 1799 9 there were nearly 1000 more retort ovens under construction at the close of the year and contracts had been made for the construction of a number of additional plants the marked progress made in re tort oven construction in the last two or three years and the activity evinced fn an new work under way or in contemplation are carrying forward rapidly the revolution in coke making which was noted in one of the ahe earlier survey reports as inevitable this revolution consists not only in the gradual substitution of retort ovens for the wasteful beehive type but in the shifting of the coke making industry from the vicinity of the mines to the centers of manufacture and population where the gases may be utilized and the other byproducts readily disposed of the quantity of coal required to produce a ton of coke is much less than formerly the average gain in 1912 com pared with 10 years ago is probably at least pounds it is doubtful if in m the earlier years the actual yield of coal in coke exceeded 60 per cent whereas in 1912 it was 67 per cent according to the survey this gain is largely due to the increase in the production of product byproduct by coke in which the yield of coke from a ton of coal is very much higher than in making beehive bee hive coke in illinois indiana massachusetts michigan new jersey new york aw and wisconsin where coke is made exclusive ly in product byproduct by plants the yield varies from per cent in wisconsin to per cent in indiana whereas in the states where beehive practice prevails the yield in 1912 varied from 50 per cent in georgia to per cent in pennsylvania it is now twenty years since coke was first manufactured in product byproduct by iby ovens in the united states by this process all the products of the coal are conserved first of course the coke but also large quantities of coal tar ammonia gas and other constituents it is asserted that in the byproduct by product coke plants of the present day the products byproducts by pay the cost of the process that is that the coke is clear gain the old method of coke making by means of the beehive oven which is in fact still largely in use allows all these valuable products byproducts by to waste absolutely the first plant using the byproduct by product or retort type of oven was installed at syracuse new york in may 1893 this pioneer plant consisted of twenty semet solvay ovens and produced in that year 12 tons of coke the plant has since been increased to forty ovens the second byproduct by product plant to be constructed was one of sixty otto hoff mann ovens at johnstown pennsylvania from these small beginnings the byproduct by product branch of the coking industry has grown steadily new plants being added each year until at the close of 1912 there were ovens of this type in operation and the production of retort coke for the year was tons or a little more than one fourth of the total output the making of byproduct by product coke has materially developed along other lines than in the simple building of new ovens and increased production the ovens of the present day are larger higher and wider than those installed in earlier times the charging capacity of the original ovens at syracuse was 44 tons of coal and the time required for coking was twenty four hours even at that time a gain of bf at least 50 per cent in coking time was obtained compared with beehive practice which required forty eight hours for the production of furnace coke and seventy two hours for the production of foundry coke cohe the semet solvay ovens of today hold h 01 d at the average about sixteen tons of coke the exact capacity depends of course on the specific gravity of the coals used the original 60 otto hoffmann ovens at john johnstown S had a charging capacity of about 5 tons each the latest installations of united otto ovens at mayville wisconsin in 1912 have an average capacity of 1033 tons of coal each the coking time has been materially reduced so that excellent furnace coke is now made in sixteen to eighteen hours the development of m modern mechanical appliances ances has also done much to forward the efficiency of the retort oven and to reduce the labor necessary per unit of output the same crew of men who twenty years ago were required to handle twenty five of the small ovens and who were carbonizing say tons of coal a day are able with modern equipment to handle fifty or more of the larger ovens coking 1000 tons of coal a day this represents an increase of about in the tonnage carbonized per man employed these developments have been accompanied compa nied by marked improvements in byproduct recovery in the manufacture of ammonia and other products byproducts by twenty years ago the only ammonia recovered was in the form of crude liquor running from 12 to 15 per cent am ammonia imonia now coking plants are producing ammonia liquor ranging from froin crude through the different grades required for the manufacture of nameless powder etc to the production of almost chemically pure aqua ammonia at one operation still another marked development in product byproduct by oven practice is in the adaptation of the surplus gas to the illumination of cities and towns in the earlier days the ovens produced only a small and irregular quantity of surplus gas of varying quality today byproduct ovens in the united states are selling from forty to fifty million cubic feet of gas a day for illuminating purposes almost th the entire supply of ga gas s in some cities is derived from retort ovens among these cities may be specially mentioned boston massachusetts camden new jersey indianapolis di anapolis indiana hamilton ohio baltimore maryland duluth minnesota south chicago illinois and milwaukee wisconsin until 1908 the Semet Solvay and united otto otto hiffmann ovens held the entire field of retort oven practice in that year however the illinois steel company constructed ted at joliet illinois koppers regenerative byproduct ovens this plant was doubled in the following year and a number of other plants of this type t ype have since been constructed in daffe different rent parts of tho the country in 1909 construction was begun on didler ovens at south bethlehem pennsylvania but they had not been put into blast at the close of 1912 during 1912 a bank of twenty two klonne ovens was ed at muncie indiana at this plant all the gas from the ovens is supplied to the city of muncie the ovens are heated with pra ducer gas made from the coke two recent installations of semet solvay ovens one at waukegan wauregan kegan illinois and the other at indianapolis indiana are constructed on the same plan |