Relation between coking condition and maximum driving pressure developed in coke oven was studied by means of medium size coke oven with movable walls designed and built by the authers.
1) If coal is heated up slowly from room temperature, the longer the coking time, the higher the maximum driving pressure and the higher the hardness of coke produced.
2) Maximum driving pressure is reduced and hardness of coke is raised by pulverization, in the case of coal small in fluidity such as Shikamachi and Sunagawa coal.Both of maximum driving pressure and, hardness of coke are reduced by pulverization in the case of coal extremely small in fluidity such as Tagawa coal.In the case of coal, extremely high in fluidity as Miike coal there occures almost no change in maximum driving pressure even by the grinding of coal powder.
3) The higher the bulk density of coal in coke oven, the higher the maximum driving pressure.
4) Driving pressure is lowered by the increase of moisture in coal charged.Moisture gives more large influence for the driving pressure than that given only by the decrease of bulk density culculated as dry base.
5) Driving pressure is lowered by weathering, while almost no influence appears in the swelling number and content of oxygen.
View full abstract