Desempenho operacional da ETE Cabanga-Recife-Pernambuco.

Abstract

This work shows the results of the monitoring of a primary treatment domestic sewage treatment plant (pre-treatment), primary decanters, anaerobic digesters, gas burners and drying cells, digested sludge. The station, in a real scale, belonging to COMPESA (Companhia Pernambucana de Saneamento), called ETE CABANGA was located in the neighborhood of the same name, south of the city of Recife, Northeast Brazil (8º 10 '52 "S, 34º 54' 0 "0, and altitude of 2m). Analyzes of the raw sewage and liquid effluent from the decanters were carried out in the period from November 1 to November 1992, with monitoring of the volumes of raw sludge produced between June and November of the same year. Receiver bodies were also analyzed in the period from April to October, at points upstream, downstream and at the launch point of the ETE liquid effluent. All the analyzes for the gross effluent liquid effluent were performed in the COMPESA laboratories in punctual samples collected at 12 o'clock in samples collected during the daily cycle. For the recipient body samples were collected in hours of preamar and low - sea. The parameters investigated for the raw sewage and effluent were: pH, temperature, suspended solids, sedimentable solids, BOD =, chloride, total sulfide, fecal coliforms and helminths (Ascaris lumbricoides, Trichuris trichiura and Hymenolepis nana). In the receiver body were measured dissolved oxygen and BOD =. Even though the ETE, during the monitoring, behaved in terms of efficiency as expected, it produced poor quality effluent, mainly regarding the microbiological parameters. Being fed by a collection system (collecting network), during the monitoring, it was detected to be connected with the city's rainwater drainage system and, with this network collecting a large number of elevator stations, both the raw sewage and the effluent presented high average concentrations of chloride and total sulfide, and for the raw sewage, 2863mgC1- / 1 and 39mgS- / 1 for chloride and total sulfide, respectively. The conditions of the receiver body regarding the parameters studied in the same were inadequate for the reception of the effluent liquid of the TEE, presenting, in the most favorable situations, 72% of the saturation level for the dissolved oxygen upstream of the launch, while BOD = mean was 15mg / 1 at this point and in the hours of preamar. As for the volumes of raw sludge produced, these were practically the same as expected volumes based on the literature consulted.