Desarrollo de un método para la recuperación de carbonato de calcio de los lodos residuales en la Empresa Ecuamarmol.

Abstract

The object was the development of a method for the calcium carbonate recovery of the sewage ludge at ECUAMARMOL Company, which resulted from the mixture of rocky dust and water used in the productive process in the cutting and polishing stages; the sewage sludge is transported by canals to a sedimentation and thickening pool; after, it is stored in canvas until it is taken to the city landfill. The stated method analyses sampling parameters for its treatment at a laboratory and so being able to determine requirements as: physical (pH, humidity, mesh light) and chemical (Percentage of calcium carbonate) based on the current Ecuadorian regulations. The aim of the company was proving the feasibility of recovery of calcium carbonate based on this study and turn it into an industrial process. Hence, the drying was chosen to find out a functional temperature, the mechanical disintegration in a mill for the homogenization of the sample and sieving in order to determine the mesh light. The necessary conditions and transformations to separate the biggest amount of calcium carbonate from sewage sludge were determined after characterizing its primary components, then three samples were analyzed which were exposed to different drying temperatures in an electric tray dryer (80, 85 and 90 o C) after that, to a milling stage in a ball mill (during 1 hour) and sieving (7-sieve tower). This way, the results obtained prove the viability of recovery of calcium carbonate and so to end the research. The dry sample to 80 o C showed a percentage of calcium carbonate to 98,8%, being the highest obtained which was categorized as type A and granular fertilizer.