Effect of Variation in the Process of Manufacturing and pH on the Hardness of Urea Molasses Mineral Mixture Blocks

摘要

Urea molasses mineral mixture blocks (UMMB) were manufactured by altering the sequence of mixing of various ingredients and changing the pH by addition of sulphuric acid. In first experiment, the UMMB were manufactured by eight different manufacturingprocedures by altering the sequence of mixing of CaO, urea and phosphoric acid. The sequence of mixing of ingredients was molasses, CaO, H_3PO_4, ground urea and concentrate mixture; molasses, CaO, H3P04, dissolved urea and concentrate mixture; molasses, ground urea, CaO, H_3PO_44 and concentrate mixture; molasses, dissolved urea, CaO, H_3PO_4 and concentrate mixture; molasses, ground urea, CaO, and concentrate mixture; molasses, dissolved urea, CaO, and concentrate mixture; molasses, CaO, ground ureaand concentrate mixture, and molasses, CaO, dissolved urea and concentrate mixture for treatments A_1, B_1 C_, D_1, E_1, F_1, G_1, and H_1, respectively. In second experiment, the pH of the blocks was maintained by adding different levels of concentratedsulphuric acid (14-25 ml H_3PO_44/ 500 g of blocks). The blocks were prepared by using the cold process. The level of molasses (40), urea (10), CaO (6), mineral mixture (6), phosphoric acid (1), mustard cake (10) and deoiled rice bran (27) were kept constant. The hardness of blocks was measured by using a penetrometer. Blocks Hardness, decreased (P<0.05) with increasing levels of sulphuric acid and increased, with increase of pH. Urea, CaO, phosphoric acid and sulphuric acid had significant (P<0.05) effect on the temperature rise. The sequence of mixing the ingredients affected (P<0.05) the hardness of lick blocks. The hardness of the blocks increased (P<0.05) with the increase of storage time.