History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c13.s2.t4.133

v1.c13.s2.t4.133

Prakash, B. (1990) has done a detailed study of the operating parameters and heat and mass balance of some of these furnaces and he has observed that the furnace temperature was controlled to 900 to 1000°C during reduction and raised to 1250 to 1300°C in the last phase by controlling the blowing rate of air as shown in Table 5. Bloomgren and Tholander (1986) have studied the constitution of iron smelting slags and the environmental conditions inside the low shaft furnaces and they have concluded that Fayalite (2FeO.SiO₂) slag or its Eutectic with FeO having a melting point of 1205°C and 1170°C respectively prevent the carbon pick up by the reduced iron, and thus in this process the furnace productivity is decreased. *Tables 6* and *7* show the heat and mass balance for the Jiragora furnace operated by the tribals in the presence of Ghosh(1964) and this has confirmed the aforementioned