Abstract
Heavy oil injection test was conducted in No. 3 blast furnace (hearth diam. 7.15m) of Kawasaki Iron Works of Nippon Kokan K. K. for about six months from April to September, 1961.
As a result of observing the combustion condition within the furnace operated by injecting heavy oil through one tuyere at first, it was confirmed that there was scarce trouble in facilities and operation.
Then, in the test operation with injection of 32kg heavy oil per ton of pig iron through four tuyeres, the coke ratio fell, while (the coke rate decrement) / (oil rate) showed the value of1.6-1.7 and the quantity of tapped pig iron increased by 5%.
On the basis of these test results, heavy oil was injected into No. 2 blast furnace (hearth diam. 7.2m) through all tuyeres by automatic feeding device completed in September of 1961.
In this test operation, coke ratio fell remarkably with heavy oil injection of up to 50kg per ton of pig iron and the rate of replacing coke with heavy oil showed the value of about 1.7. In the case of injecting heavy oil more than 50kg, this rate lowered and coke ratio showed the lowest value of 470kg per ton of pig iron at the time of injecting 75kg heavy oil. While in the case of injecting heavy oil more than 75kg, lowering of coke ratio and increase of tapped pig iron quantity were not recognized.
