Recent Developments

One of the most important developments in the OH process in post-war years has been the replacement of producer gas by fuel oil. While marked improvements in productivity have been shown in several cases as a result of this change, it is perhaps significant to note that the use of this rich fuel has not resulted in any marked increase in fuel efficiency. Another factor is that greater attention has been paid to the reduction of metallurgical load in the OH furnace. With increasing production, the load on the active mixers has gone beyond the point at which effe-ctive refining of the hot metal is possible and in general the function of the active mixer has tended to become that of a storage vessel with facilities to melt scrap unsui-table for charging direct into the OH furnace.