PL20040B1 - Method to prevent salt baking. - Google Patents

Description

Many commercially manufactured salts tend to cake when stored, forming more or less hard masses that are difficult to break, be it with a shovel or with the aid of mechanical devices. Such breaking up entails considerable costs. Baking of the salt can also take place during transport, for example in wagons or boats, causing inconvenience for unloading. When using such parched salts, there are further disadvantages, such as bad sowing of parched fertilizers, slow dissolution of parched salts, clogging and damage to transport equipment. changes, such as, for example, superphosphate and others, but also in the case of salts, which are not accompanied by chemical changes during storage. In the case when salt sintering is caused by the crystallization of tiny salt crystals from the remnants of the salt solution adhering to crystals or a solution produced by the absorption of moisture by salt, are usually successful by drying well and then protecting the salt from moisture, reducing its tendency to sinter. Many salts, however, sinter to a large extent also without the access of moisture. pants, 'because I salt the fine grains more strongly than the salts, in larger aggregates. It has now been found that the above-mentioned sintering phenomenon can be completely removed, or significantly reduced, by adding inorganic colloidal substances to the salt, which have the ability to form a protective layer on individual salt grains. As such a medium, for example, iron hydroxide obtained by treatment with sodium lye on iron sulfate is suitable. The iron hydroxide is oxidized in air to ferric hydroxide, which forms a protective film on the salt grains. How delicate this protective coating is is due to the amount of Fe needed to form the above coating. A quantity of Fe of one or a few hundredths of a percent is sufficient. The present invention is not limited only to iron compounds, which have the only advantage of being the cheapest and therefore suitable for large-scale use. Other colloidal inorganic substances may also be used, especially when the presence of iron is undesirable. Freshly lost magnesium, aluminum, manganese and the like hydroxides, which are suspended in the form of a slurry and added to the salt before their final drying, are suitable. this method was chosen so that they themselves exhibit favorable properties, such as, for example, manganese in artificial fertilizers. Example I. 100 tons of 80% potassium chloride, produced for fertilizing purposes, are mixed thoroughly before drying, with a ferric hydroxide suspension, which is obtained by adding 12 kg of sodium liquor to a solution of 115 kg of crystalline ferrous sulfate (FeSO4. 7H2OJ in 430 kg of water. After drying, potassium chloride is obtained, showing an abundance of salt). usually have a long shelf life. Example II. 1 ton of Chilean nitrate is mixed with a suspension of magnesium hydroxide, prepared by adding 1.3 kg of sodium lug to a solution of 1.5 kg of magnesium chloride in 10 kg of water. Saltpeter with the above-mentioned additive is very stable for storage. Example III. 10 tons of high-percentage (about 99%) potassium chloride used in the electrolysis are treated with an aluminum hydroxide suspension prepared by adding 95 kg of potassium liquor to a solution of 75 kg of crystalline aluminum sulfate (Al2 (SOJ3.18H2O) in 450 kg of water After drying, potassium chloride is obtained completely free of sintering. PL

Claims (1)

1. Thirdly, not patented. A method of preventing sintering of salts, especially fine-grained, prone to sintering without the access of air moisture, characterized by the fact that the salts are mixed with inorganic colloidal substances, used in amounts less than 1%, most preferably with insoluble hydroxides before drying. of metals in the form of suspensions formed by the action of the liquor on a solution of a metal salt. Wintershall Aktiengesellschaft. Deputy: Dr. inz. M. Kryzan, Patent attorney Druk L. Boguslawski i Ski, Warsaw. PL