Abstract: The invention relates to a method and an assembly for recovering magnesium ammonium phosphate from slurry supplied to a reaction container (10) in which an aerobic milieu that is alkaline as a result of CO2-stripping is present and in which the slurry is guided in a circuit with the aid of ventilation. Cationic magnesium, such as magnesium chloride, is added to the slurry, and magnesium ammonium phosphate crystals which are crystallized out of the slurry are removed via a removal device (30) provided in the base region of the reaction container. The slurry is supplied from the first reaction container (10) to a second reaction container (12) via a first line (14), wherein an anaerobic milieu is set in the second reaction container in order to redissolve the phosphate, and MAP crystals crystallized in the second reaction container are supplied to the first reaction container.

Abstract: The disclosure discloses a method for preparing calcium oxide using multistage suspension preheater kiln. The steps of the method are: (1) the limestone powder is fed to the multistage suspension preheater kiln for preheating to 800° C. to 900° C.; (2) A preheated material is fed to a decomposition furnace, and calcined at 900° C. to 1100° C. for 25 s to 35 s; (3) A calcined material is fed to a rotary kiln, and calcined at 1100° C. to 1300° C. for 25 to 35 minutes, and finally cooled to obtain calcium oxide.