Prospectus of waste stabilization ponds in Ceará, Northeast Brazil

Abstract

WSP technology has been used in Ceará, Northeast Brazil, since middle 1970s. There are presently 96 ponds plants and most of them are comprised by single cells (40%) and series of 3 ponds (35%). They were under loaded due to incomplete house connections to the sewerage network and low per capita wastewater contributions. Highest removal rates of organic material, ammonia and faecal coliform were found in 3 pond series. Faecal coliform removal was in accordance with the literature and series of ponds reached numbers ≤10(5) cells/100 ml. In series with 4 and 5 ponds FC was below 10(3) cells/100 ml. Ammonia removal varied from 30 to 80% and total phosphorus the removal was not significant. An increase in the number of maturation ponds enhances nutrient and coliform removal. Up-grading schemes should be investigated as well as effluent reuse potential.

Waste Stabilization Ponds

“…to 2 f,g~0 to 1 f,g 2.2 (1.9 to 2.4) a Sources: (Al-Salem and Lumbers, 1987;Anceno et al, 2007;Araki et al, 2001Araki et al, , 2000Ayres et al, 1993;Bausum et al, 1983;Bouhoum et al, 2000;Da Silva et al, 2011;De Oliveira et al, 2011;Dixo et al, 1995;García et al, 2008;Grimason et al, 1996aGrimason et al, , 1996bHachich et al, 2013;Hassani et al, 1992;Hewitt et al, 2011;Joshi et al, 1973;Konaté et al, 2013aKonaté et al, , 2013bMara and Silva, 1986;Nupen, 1970;Oakley, 2004;Oragui et al, 1995Oragui et al, , 1987Ouazzani et al, 1995;Rao et al, 1981;Pescod, 1992, 1991;Schwartzbrod et al, 1989Schwartzbrod et al, , 1987Stott et al, 2003;von Sperling and Mascarenhas, 2005;von Sperling et al, , 2003von Sperling et al, , 2002Young et al, 2016). Typical log 10 removals are arithmetic mean values of the log 10 removals reported in the literature; typical ranges are +/-one standard deviation of the mean.…”

Thermo-tolerant coliform bacteria decay rates in a full scale waste stabilization pond system in Northeast Brazil

“…The K b value of 6.20 d À1 adopted for the design of all the ponds in the series, assuming complete mixing, is higher than the observed mean value of 0.85 d À1 . A K b of 6.20 d À1 is more acceptable for use with shallow maturation ponds (deptho1.25 m) and with organic loadings less than 350 kgBOD 5 /ha.day on the primary facultative pond (Silva et al 1996).…”

“…Table 7 presents the K b values obtained in pilot scale ponds in northeast Brazil (Farias 1989;Oragui et al 1995;Silva et al 1996).…”

Innovative Wastewater Treatment Technologies — The INNOQUA Project

“…Pescod (1992) found something similar in Jordan where the As Samra Pond exceeded its design organic and hydraulic load by 57% and 25%, respectively. The assessment of 95 WSPs in Ceará, Brazil indicated, on the contrary, that all ponds were under-loaded as a result of a low household connection to the sewer network (Da Silva et al, 2011). Maintenance problems are also a factor that can explain poor performance of WSPs.…”