THE COLLIERY GUARDIAN AND JOURNAL OF THE COAL AND IRON TRADES. ______________________________________________________________________________ Vol. CV. FRIDAY, APRIL 18, 1913. No. 2729. _______________________________________________________________________________________________________________________________________ PROGRESS IN BY-PRODUCT RECOVERY AT COKE OVENS * By J. E. Christopher. At the present time the chief outlet for coke is the iron industry, which uses approximately three-fourths of the whole. The diagram (fig. 1) shows the progress of the iron industry since the introduction of coke as a fuel and the outputs of pig iron in round figures. About 1870, extensive trials were made by Messrs. Bell Brothers and the Wigan Coal and Iron Company of the Pernolet type of coke oven. The type put down by the latter firm was a modification by Young. Aitken and Jameson also endeavoured to adapt the beehive- shaped oven for the recovery of by-products, both following the plan of downward suction. All these •early adaptations failed on account of the doubtful quality of the coke produced. The Pernolet oven was rightly designed, in that the chamber was kept enclosed and air excluded as much as possible, but the distillation about considerable improvement in this respect. In 1873, 30 of these ovens were in operation near Sheffield, and in 1874 60 more were built at Ebbw Vale Ironworks. Hard metallurgical coke was made in these ovens, and the advantages of the retort-shaped oven began to be realised. Thus, from a combination of the Pernolet type of oven, with its enclosed chamber and external heating, and the Coppee oven, with its narrow chamber rapidly heated, we arrive by gradual stages at Shortly after this the Semet-Solvay oven was brought out, but for some time the by-product oven made little progress owing to the prejudice of the ironmasters against the appearance of the coke, but once this prejudice was overcome, the by-product oven made phenomenal progress. This progress is best shown by fig. 2, based on the annual reports under the Alkali Acts. Referring to the actual plant for the recovery of ANrtUAL PRODUCTION 8 DABBY USED COKE —? f 4f t " ' first record of enclosed overs J LORO OUNDONALD'S patent --------------J ‘•VOOLIWR PROCESS INTRODUCED ----------- GAS LIGHTING INTRODUCED MOT BLAST INTRODUCED ------ BESSEMER PROCESS INTRODUCED OPEN HEARTH PROCESS INTRODUCED BASIC PROCESS INTRODUCED ~ BYE-PRODUCT RECOVERY AT ______ COKE OVENS ESTABLISHED WO'RK 5 ANNUAL PRODUCTION OF SULPHATE AMMONIA COME oVCHS Fig. 2. was, after all, a low-temperature one, and consequently "the tars produced were thin, containing a large percentage of paraffin bodies, whilst the sulphate yield was low. The following yields are quoted from con- temporary papers:— Tar Sulphate (galls, per ton) (lb. per ton). Bell Bros. (Pernolet) ...... 5'37 ... 414 ................... Wigan Coal and Iron Company — ... 5*6 Aitken.................... 10 to 11 ... 5'5 Jameson.................... 6'2 ... 6'3 Gasworks are quoted as giving at that period 10 gallons of tar per ton and 16 lb. of sulphate. However, a later development of the Pernolet oven was erected at the Shamrock Pit, Westphalia, in 1886, in which a regenerative system was used. The disadvantage of coking in comparatively deep layers, especially with lean coals, being now apparent, attention was drawn to the methods of heating the ovens, and the Coppee oven was introduced, bringing *From a paper read before the Society of Chemical Industry (Manchester Section), February 15, 1913. PURIFIERS GAS COOLER COOLERS sniL EXHAUSTER EFFLUENT LIQUOR TAR A AMMONIAC LIQUOR LtOUOR STORE TANK amucnha vapour r-----, ±_ \ TARt- KOPPERS PROCESS. neater. COOLER EXHAUSTER FA« SATURATOR LIQUOR LIQUOR STORE TAN! MONT CENIS PROCESS. exhauster STILL SATURATOR y TAR St AMMONIAC AL LIQUOR AMMONIA VAPOUR £--------4--- x-; TAR TO STORE