Process for granulating potassium sulphate

摘要

A rolling granulation process using starch as granulation aid is proposed for potassium sulphate, which comprises dry activation-milling of a part of the potassium sulphate and moistening the material to be granulated with practically pure water, building up the green granules by rolling on a granulating pan or in a rotating drum and drying the green granules at a temperature between 105 and 120 DEG C to a residual moisture content of from 0.1 to 0.5%. To improve the wettability of the primary particles and to reduce the amount of water necessary for moistening, a soluble salt of lignosulfonic acid is used in an amount of from 0.1 to 1 kg/t of fresh material to be granulated.