Criterios de diseño para lagunas de efluentes de tambos en condiciones nacionales

Abstract

The concept of “best applicable technology” has been adopted as the basic guidance criterion for the development of dairy farm effluent treatment. Systems of pond in series (an anaerobic pond followed by a facultative pond) have been widely used in milk‐producing countries, as New Zealand and Australia. Dozens of these systems have been built in Uruguay according to the designs of these first systems. However, the criteria were not adapted to the conditions of the national production. These passive systems were originally designed and built for domestic wastewater treatment. When they treat dairy farm effluents they achieve an important reduction of the organic load, but they do not meet the nitrogen, phosphorus and pathogen limits required by the legislation to discharge these effluents into water bodies. Significant differences between domestic and dairy farm effluents such as the proportion of solids and the C:N:P ratio, and their concentrations, justify this inefficiency. This work intends to discuss the results obtained from pond systems designed according to domestic wastewater criteria or according to criteria imported from other countries, and to present design equations for this type of systems that are operated under the conditions of the national production.