PHOENIX-LANCE STEELMAKING Here is an interesting new steelmaking techniqu~ being develope~ in Germany for the production of open-hearth quahty steels from htgh­ phosphorus pig irons. It utilizes the classical basic-bessemer converter with top-blown oxygen, and has the advantages of early phosphorus removal and, consequently, less nitrogen pick-up in the final steel. by H. Th Brandi Ruhrort plant of Phoenix-Rheinrohr AG 11,0 t the L 11. l!.ll A in Germany, tests have led to the development 3,8 i of a new steelmaking process. This is the Phoenix­ 3,8 '\ Lance, or the PL process, which is now ready for in­ ll II 3,8 I dustrial application. {C) I Z,'f \- The new process, for which a patent application I z,o J I has already been filed, is conducted in the usual, I converter is not only >-.. basic-bessemer converter. The Fig. !-Reaction curves but the blow "" [P} f' bottom-blown in the upright position, for a blow using the 1,11 I I is continued for a period with the converter tilted Phoenix-Lance process. l" ~ o.a I metal-slag reactions of on its side, thus obtaining 0,'1 \ r--... I the same kind as those occurring in the open­ ill! hearth furnace. 0 is 70 to 80 pet, equaling that obtained in the Operation of PL process buffer slag tests by Kosmider; Schenck, and others; The operation of the PL process will be clear the resulting advantages are obvious. Five PL heats from the accompanying reaction curves for a blow, had the following average analyses: 0.114 pet C, Fig. 1. In the first stage of the process, basic­ 0.298 pet Mn, 0.028 pet P, 0.014 pet S, and 0.004 pet bessemer pig is refined by bottom-blowing to a N. carbon content between 0.4 pet and about 0.1 pet. Total blowing time is about 15 min, or little Then, for the second stage, the converter is tilted longer than in the ordinary, basic-bessemer process. on its side, to act for a time as a kind of open­ Oxygen consumption is about 2500 cu ft, of which hearth furnace. over 50 pet is provided by atmospheric oxygen. A water-cooled oxygen lance is now introduced into the mouth of the converter. By blowing plant Importance of PL process oxygen, or pure oxygen, on the melt, t?: sla~­ As already mentioned, the importance of the formers are quickly melted down, obtammg, m basic-bessemer process for Western Europe remains addition to a slight degree of decarburization, a demonstrable, since there are still available steady slagging-off of the phosphorus. supplies of high-phosphorus ores sufficient for Finally, a brief raising of the converter and blow­ many years. ing with blast air and/or oxygen-boosted blast, The fact that the corresponding open-hearth lowers the phosphorus percentage within a few steels with low copper and tin contents have to be seconds to values of the order of 0.020 to 0.040 pet. made from pig-irons-hence from ores-particularly It is generally possible simultaneously to control low in such undesirable metallic contaminations­ the carbon content of the steel bath within 0.02 to is a considerable advantage of the present process. 0.10 pet, or higher values, if required. Naturally, by From the point of view of the steelworks applying a secondary slag, the phosphorus conte?t operator, the PL process affords substantial of the steel can be fairly easily brought down m operating advantages. During a campaign, the essentially the usual manner to quite low levels. blowing characteristics of a converter tend to The final slag, i.e., the slag after the third process change considerably. Furthermore, in a bessemer stage, corresponds to an ordinary basic slag? . and plant above all others, much depends on main­ can be credited with its full value as a ferhhzer. taining a suitable working rhythm, this applying Since the PL process enables the dephosphorizing equally to the sequence of heats, and to the re­ to be conducted in practically the same manner as lining of the converters and bottom replacements. in an open-hearth furnace, and the carbon per­ It is immediately obvious that retaining the clas­ centages at the end of the actual refining blow are sical bessemer converter and using it for the pro­ of the same order of magnitude as in the open­ duction of steels equal to open-hearth quality, hearth process, the problems of nitrogen and brings with it the considerable advantages of the oxygen elimination are practically solved. The fast-working rhythm and operational readiness of nitrogen figures for PL steel are between 0.003 and the converter plant. 0.005 pet, while the oxygen percentages follow t~e These considerations have impelled Phoenix­ carbon content of the refined, finished steel, as m Rheinrohr AG to contemplate the construction of the open-hearth or the LD process. Desulfurization an entirely new basic-bessemer steelworks of the H. Th. BRANDl is with Phoenix-Rheinrohr AG, Diissel~orf, classical type. Germany. This article originally appeared in ~tahl .und E1sen, (At the Ruhrort plant of this firm, plans have been formulated June 26, 1958, and a translation was later pubhshed m the Iron for the construction of a new plant for the production of 6000 cu m per hr of 99.5 pet 0 2 to supply converters being fitted with the and Coal Trades Review. Phoenix-Lance. Ed.) 118-JOURNAL OF METALS, FEBRUARY 1959 .