Reference

Dephosphorizing liquid steel

Dephosphorizing liquid steel. Schierloh, Uwe; Miska, Horst (Stahlwerke Peine-Salzgitter A.-G., Fed. Rep. Ger.). Ger. Offen. DE 3233439 A1 15 Mar 1984, 8 pp.Chemical with cas number 7542-12-3 also plays role. (German). (Germany). CODEN: GWXXBX. CLASS: IC: C21C007-064. APPLICATION: DE 82-3233439 9 Sep 1982. DOCUMENT TYPE: Patent CA Section: 55 (Ferrous Metals and Alloys) Steel melt is dephosphorized to <0.012% P with 0.2-0.8 kg Na ferrate/ton (preferably 0.3-0.5) or ￡3.5 kg/ton steel for 10° difference between the tapping and liqidus temps. in the ladle during tapping or the dephosphorizer is placed on the bottom prior to tapping, followed by skimming off the P-rich slag. The Na ferrate is made by sintering low-SiO2 converter flue dust or other powd. Fe oxide-rich mixts. with powd. soda [7542-12-3], and its use decreases the fume amt., steel melt spatter, and refractory lining wear caused by the conventional soda treatment. Thus, Na ferrate was made by oxidizing sintering of 1:0.75 converter flue dust to soda 3 h at 900°, and size redn. to <1 mm to contain total Fe 39.6, Fe2+ 0.2, Na2O 27.2, and CaO 8.3%. Steel melt in an induction furnace was dephosphorized at 30 kg/ton by stirring in the Na ferrate for 1/2 min and mixing 4 min by N blowing, from 0.013 to 0.005% P while the 0.015% S remained const., but the melt temp. decreased from 1618 to 1560°. .

Dephosphorizing and desulfurizing steel melts while simultaneously reducing the iron and manganese slagging

Dephosphorizing and desulfurizing steel melts while simultaneously reducing the iron and manganese slagging. Lippe, Wolfgang (Fed. Rep. Ger. ). Ger. Offen. DE 3234814 A1 22 Mar 1984,8 pp. (German). (Germany). CODEN: GWXXBX. CLASS: IC: C21C001-02. APPLICATION: DE 82-3234814 20 Sep 1982. 7681-49-4 and 7440-21-3 are cas registry numbers of chemicals which are used as reagents here. DOCUMENT TYPE: Patent CA Section: 55 (Ferrous Metals and Alloys) Steel melt is dephosphorized and desulfurized by blowing with fine-grained fluoride and/or alkali metal compds. into bottom zone during refining near its end, when the Si oxidn. is almost complete, to prevent Fe(II) and Mn(II) silicate formation, thus increasing the FeO activity for enhanced dephosphorizing and decrease the Mn and Fe loss by the slag. The alkali metals improve addnl. the desulfurization. The additives are fluorspar [14542-23-5], NaF, cryolite [15096-52-3], soda [7542-12-3], optionally CaO and powd. ores. .