| 摘要 |
<p>The invention relates to filtering materials having laminated porous rigid structure and complex composition, formed as elements of various shapes, made up of grained materials and binders, meant for purifying liquids, especially water, by filtration, adsorption, ion exchange, chemical or catalytic processes of great efficiency. According to the invention, the filtering materials comprise serial layers obtained by thermal sintering of active materials, having the physical, chemical and bactericidal characteristics required by each purification stage, with controlled grain-size and high melting points, mixed with thermoplastic polymer powders, resins or thermal degradation binders, in an active material/binder mass ratio of 10/1...1/5. The process for making the claimed filtering materials comprises the stages of: mould setting in serial layers, from coarse grain size to fine grain size, coating the outlet surface with a mixture of very fine powder of active material and a binder with high fluidity at the temperature of thermal treatment, in an active material/binder powder mass ratio of 1/2...1/10, thermally treating at a temperature which is set depending on the nature of the binder so as to ensure the structure (layer) binding and, optionally, the coating of the outlet surface with a fluid mixture of very fine powder of active material and binder with high fluidity at a temperature lower than the temperature of thermal treatment, in an active material/binder powder mass ratio of 1/2...1/10.</p> |
