Some observations in the production of ferro-phosphorus in low shaft furnace

Smelting trials were undertaken to assess the possibility of producing ferro-phosphorus in the 12-15 tons per day experimental low shaft furnace. The phosphate rock used in the investigation contained about 33.5% P2O5. Phosphate rock was crushed to suitable size and charged along with iron ore, nut coke and usual fluxing agents into the furnace. The theoretical quantity of rock phosphate required to obtain 5% and 10% phosphorus in the product was calculated and added to the burden in two stages. Observations made indicate increase in slag volume and fuel consumption with higher amounts of phosphate rock in the burden. The actual phosphorus content in the product was observed to be 4.8% and 7.6% in the two stages respectively. No difficulties were encountered during the smelting trials rather the operations of the furnace including the gas cleaning equipments were smooth. It was, therefore, concluded that furnace including the gas cleaning equipments were smooth. It was, therefore, concluded that a suitable grade of ferro-phosphorus could be successfully produced in the Low Shaft Furnace. (Prof. V.A. Altekar, Director; Sarvashri A.N. Kapoor, J.Goswami, R.S. Singh & S.R. Ghosh, Scientist; and Shri S.B. Ghosh, Senior Scientific Assistant; National Metallurgical Laboratory)