A METHOD OF PRODUCING A CERAMIC FILTER MEMBRANE, A METHOD OF IMPROVING A CERAMIC FILTER MEMBRANE AND THE CERAMIC FILTER MEMBRANE OBTAINED BY THE METHOD

Methods of producing a ceramic filter membrane and of repairing a ceramic filter membrane and the so obtained membrane. The method for producing a membrane includes a first step of applying a first dispersion comprising ceramic particles of a first medium grain size and ceramic particles of a second medium grain size to a porous substrate, the second medium grain size being smaller than the first medium grain size, drying and sintering the ceramic particles. The so obtained membrane layer is surface treated with a second dispersion comprising ceramic particles of a third medium grain size in the interval -10-+ 10% relative to the first medium grain size and ceramic particles of a fourth medium grain size smaller than the third medium grain size. The surface treatment of the membrane layer occurs by passing the second dispersion in a main flow direction along the membrane surface layer in a turbulent flow while providing a pressure difference over the membrane layer, drying and sintering the so treated membrane. The method for repairing a ceramic filter membrane comprises the step of surface treating the membrane with a dispersion comprising ceramic particles of a first medium grain size and ceramic particles of a second medium grain size smaller than the first medium grain size, where the first medium grain size is larger than the average pore size of the membrane to be treated and smaller than the maximum pore size of the same membrane. The surface treatment of the membrane occurs by passing the dispersion in a main flow direction along the membrane surface in a turbulent flow while providing a pressure difference over the membrane, drying and sintering the so treated membrane. L'invention concerne des procédés de production d'une membrane de filtre céramique et de réparation d'une membrane de filtre céramique et la membrane ainsi obtenue. Le procédé de production d'une membrane inclut une première étape d'application, à un substrat poreux, d'une première dispersion comprenant des particules céramiques d'une première taille de grain moyenne et des particules céramiques d'une deuxième taille de grain moyenne, la seconde taille de grain moyenne étant plus petite que la première taille de grain moyenne, puis de séchage et de frittage des particules céramiques. La couche de membrane ainsi obtenue est traitée en surface avec une seconde dispersion comprenant des particules céramiques d'une troisième taille de grain moyenne dans l'intervalle de -10-+ 10% relati