Abstract: Process for determining the sylvine saturation in which the salt concentration in the solid matter-free crude solution through temperature determination at a temperature T.sub.M >T, and subsequently after contacting with KCl at a temperature T.sub.NS >T and heating to T.sub.M, is measured again, and from this data a saturation temperature T.sub.S is obtained. The temperature difference T.sub.S -T serves as a measure for the sylvine saturation degree. In this manner, the sylvine saturation degree can automatically be measured in intervals of seconds and can serve as a control value for the addition of crude salt in a hot solution process.

Abstract: A process of making a granulated MgO-containing potassium salt fertilizer containing potassium sulfate, and having a high abrasion resistance and high compression resistance, includes preparing a langbeinite slurry binder without an evaporation of a magnesium chloride-containing solution with heating at a temperature of from 95.degree. to 110.degree. C. with a density of from 1.6 to 1.7 g/cm.sup.3, mixing the potassium salt and recyclable fines with the langbeinite at a temperature of from 75.degree. to 100.degree. C., granulating in a granulating drum, screening to form the fertilizer and recyclable fines; and recovery and recycle of the fines. The liquid langbeinite binder can be made by mixing a mixture of magnesium sulfate and/or kieserite with potassium sulfate, schoenite and/or leonite the potassium sulfate and the magnesium sulfate being present in a mole ratio of from 1:1.5 through 1:3 and heating the mixture to a temperature of 95.degree. to 110.degree. C. with a turbidity density of 1.6 to 1.7 g/cm.

Abstract: In a method of granulating kieserite or kieserite-potassium sulfate mixtures, a portion of a delivery product is milled to dust fineness, the total product with addition of a water-soluble phosphate is fully granulated, and dried to a definite residual moisture.

Abstract: An elecrtrostatic separation of paper- and synthetic plastic material-containing mixtures is performed by comminuting the mixture, triboelectrically charging the comminuted mixture, and supplying it into a free-fall separator, wherein a paper-enriched and a synthetic plastic material-enriched fraction are produced, and in some cases they can be treated in a second electrostatic separation step to pure products.

Abstract: An arrangement for feeding a fine-particle material to be separated to an electrostatic free-fall cutter is formed as a funnel with braking inserts and inclined walls whose edges limit a small elongated rectangular discharge slot, wherein a greater wall is inclined to an opposite vertical wall which has an inclined downwardly directed guiding member, and a wedge-shaped projection with an upper horizontal surface is located at the lower edge of the inclined wall and extends into the discharge slot.

Abstract: An electrostatic free-fall separator has a feeding arrangement located upstream of the separator for feeding of fine-particle material to be separated into the electrostatic free-fall separator, wherein the feeding arrangement is formed as a funnel with braking inserts of an electrically insulated material and has walls limiting at their lower edge a longitudinal outlet slot, wherein the funnel has an inlet which is formed by one wall portion which is parallel to the outlet slot and an opposite inclined guiding surface with a lower edge extending parallel to the one wall portion so as to limit simultaneously a passage leading to the outlet slot, and two substantially vertical electrodes are arranged below the passage at a distance from one another which is smaller than the width of the passage.