P. Malinowski

Preparation methods of calcium sulphate and urea adduct

Preparation methods of calcium sulphate and urea adduct The paper presents the results of laboratory studies on the preparation of calcium sulphate and urea adduct by: grinding, compacting and mixing in the presence of physical water. A method for the measurement of urea conversion into the adduct form, which is based on the difference in solubility of free urea and the adduct bound urea CaSO4·4CO(NH2)2 in n-butanol, was developed. Mixing the reagents in the presence of physical water produced the best results. High urea conversion into the adduct form, over 85%, in the prepared samples indicates that this method can be successfully used to get CaSO4·4CO(NH2)2 adduct.

Utilization of waste gypsum in fertilizer production

Abstract The results of the study regarding utilization of the waste gypsum formed as a by-product during the production of the magnesium sulphate from dolomite have been presented. The use of this waste have been proposed for the production of granulated multi-component fertilizers containing 25% N; 8% S; 14% CaO and 3.5% MgO. In the process of fertilizer production, the urea which will be bounded with the calcium and magnesium sulphate from the waste in the form of adducts of CaSO4 . 4CO(NH2)2 and MgSO4 . CO(NH2)2 . 3H2O will be the source of nitrogen in the fertilizer. It has been stated on the basis of the laboratory tests that the fertilizer with the assumed composition can be obtained by means of granulation of the raw material pulp, along with the dried and ground product return. The possibility of the production of the fertilizer with good physical properties according to the assumed concept has been confirmed in the pilot scale

Production of compound mineral fertilizers as a method of utilization of waste products in chemical company Alwernia S.A.

Production of compound mineral fertilizers as a method of utilization of waste products in chemical company Alwernia S.A. The results of investigations on a possible utilization of waste products formed during the production of commercial and food inorganic salts are presented. Application of wastes in the production of compound fertilizers was suggested. The work covered a full research cycle starting from laboratory tests and ending on the production implementation. Fertilizer formulas were developed on the basis of laboratory tests. A possible production of fertilizers of suggested compositions was tested on a pilot plant scale. The compound fertilizer production with the use of waste raw materials was implemented in Chemical Company Alwernia S.A. It reduced the amount of wastes directed to industrial waste site.