COMPRESSION GRANULATION OF NITRATE

PURPOSE:To perform the compression granulation of nitrate in high yield by controlling the pocket volume of the compression roll of a briquetting machine in the lateral direction of said roll and setting the width of the joint edge mutually separating pockets to a specific dimension. CONSTITUTION:In the shape of a pocket, each of the widiths Ea and Ew of a joint edge is suppressed to 0.5mm or less and the yield of a briqutte is enhanced. The volume Vi of the briqutte granulated in the pocket is correlated with the supply amount distribution in the axial direction of a roll of raw material nitrate and the degree of comaction applied to the briquette is made uniform and the hardness of the briqutte is made equal and the abrasion resistance thereof is enhanced. As this means, the circular arc ai of the pocket Pi and the width wi thereof are made equal and the depth di of the central part pocket is made large and the depth di of the end part pocket is reduced. When the supply amount distribution in the axial direction of the raw material is set to 100 at the central part pocket, the end part pocket is set to about 92 statistically. The volume of the pocket is pref. about 90 or less at the end part with respect to 100 of the central part. The silver nitrate brequette prepared by this method is enhanced in yield and reduced in breakage.