Diseño y Construcción de un Molino de Martillos con Tamiz Intercambiable para Pulverizar Yeso Crudo

Abstract

The Design and Construction of a Hammer Mill with Interchangeable Screen for Pulverizing Raw Gypsum will allow the learning of unitary operations in the Faculty of Sciences of the Polytechnic School of Chimborazo. The sizing of the equipment was carried out by means of experimental tests, engineering calculations and process simulations with mathematical models, considering three main variables: residence time, grinding speed and particle size in the feed. The mill is constructed of 430 and 304 Stainless Steel for the housing and the feed hopper, which has a capacity of 19.43 L. The mill has 20 hammers made of DF2 steel, the grinding power is 3HP, it works with speeds of 1520 - 1774 - 2112 rpm and has an interchangeable screen of 1000µm and a screening area of 58000mm2. In the mill built, pulverized gypsum is obtained working with an efficiency of 95.5%. It pulverizes a load of 2.0 kg of gypsum in a time of 0.5 min and 75.09% of the gypsum obtained passes through a 212µm sieve, thus complying with the INEN Technical Standard for gypsum for construction. For proper grinding it is necessary that the material to be ground does not exceed 3cm in diameter, the filling volume of the equipment does not exceed 30% of the internal volume of the equipment and that the humidity of the feed is less than 15%, conditions that favor size reduction.