PROCESS FOR PRODUCING THERMAL INSULATING SEMI-ACID REFRACTORY PRODUCTS

The invention relates to a process for producing thermal-insulating semi-acid refractory products by which, in a first step, 37.5% of diatomite calcinated at a temperature of 1,000 ... 1,100 degree C is mixed, wherefrom 25% is a fraction having a granulosity ranging from to 1 to 3 mm, and 12.5% of a fraction with a granulosity of up to 1 mm, 12% of a diluted solution of aluminium monophosphate is added, in prealable with 40% of water, and after 3 min. 62.5% of a fine part comprising 40% of clay, 10% of bentonite, and 12.5% of calcinated alumine, is added, the mixture is homogenized for 5 minutes, it is pressed in shape of bricks at a pressure of 250kgf/cm2 and it is treated with a plateau at 250 degree C for 8 hours. Inventia se refera la un procedeu de obtinere a unor produse refractare semiacide, termoizolatoare, prin care se amesteca, într-o prima faza, 37,5 % diatomit calcinat la temperatura de 1000 ... 1100 degree C, din care 25 % o fractiune cu granule de 1 ... 3mm si 12,5 % o fractiune cu granule sub 1 mm, se adauga 12 % o solutie de monofosfat de aluminiu diluata, în prealabil cu 40 % apa, iar dupa 3 min, se adauga 62,5 % o parte fina, alcatuita din 40 % argila, 10 % bentonita si 12,5 % alumina calcinata,seomogenizeaza amestecul timp de 5 min, se preseaza sub forma de caramizi pâna la o presiune de 250 Kgf/cm2 si se trateaza termic timp de 60 h, cu un palier la 250 degree C, timp de 8 h.