摘要 |
Making urea prills of good impact strength by allowing drops of substantially water-free urea melt to fall, counter current to a cooling gas, through a cooling zone in which a dispersion of crystalline particles with dimensions of between 2 and 10 micron, preferably between 4 and 8 micron, in a quantity of 8-25 mg per m<3> of cooling gas, in maintained. …<??>The particles may be obtained by grinding crystalline urea. |