Efficiency of the treatment of pig production residues in covered lagoon digesters

The efficiency of two covered lagoons, designed to treat the residues of the pig production farms P-3 and T-2.1 _belonging to the Association of Pig Producers of Yucatan, Mexico was evaluated, in order to verify the feasibility of implementing this technology in Cuba. The physical-chemical and microbiological indicators of the effluents were determined and the moment of their entrance and their removal from the digesters, and upon their exit from the stabilization lagoon. The digester of farm P-3 could remove more than 90 % of the chemical oxygen demand (COD) and up to 71 % of the total suspended solids (TSS) present; while the digester of farm T-2.1 reached a removal of 78 % of the COD and 62 % of TSS. The sanitary analyses indicated that the total coliform bacteria showed an important decrease, from 2,4 x 108 to 1,7 x 103 in farm P-3 and from 4,2 x 107 to 2,7 x 103 in farm T-2.1. In both lagoons, the helminth eggs showed a reduction of 100 %. It is concluded that the covered lagoons had an adequate performance in the treatment of pig production residues, and that this technology is feasible to be used in Cuba. (author)