Tratamientos aplicables para la reducción de la DQO recalcitrantede efluentes de pulpados quimimecánicos y semiquímicos(revisión)

semichemical and chemimechanical pulping processes, due to their high yield, do not have efficient recovery systems based on combustion of dissolved organic matter. the substances discharged with the effluent of a pulp plant vary depending on the process, but generally are colored materials, materials which could be easy and difficult to biodegrade, and toxic materials. after the biological treatment of the effluent, certain amount of organic matter which is difficult to degrade remains, known as recalcitrant, and measured as chemical oxygen demand (cod). there are different methods for the elimination or degradation of these substances, as physico-chemical treatment, conventional biological treatments also with fungi, and integrated treatment processes. this paper presents a review of these methods, related to their efficiency in removing the cod of the effluent.