Sulphur and phosphorus transformations in wastewater storage and treatment reservoirs in northeast Brazil

• DOI: 10.2166/wst.2000.0643
• Publication Date: 2018-05-18T12:18:27Z
• Authors: A. L. Araújo; R. de Oliveira; D. D. Mara; H. W. Pearson; S. A. Silva
• Keywords: Hydrogen sulphide

Sulphur and phosphorous transformations were studied in two pilot-scale wastewater storage treatment reservoirs on the basis of four experiments carried out at EXTRABES northeast Brazil. The fed with effluent from an anaerobic pond after filling they allowed to rest until faecal coliform numbers dropped below 100 cfu/100 ml (10 times WHO guideline for unrestricted irrigation). During periods sulphate was reduced sulphide which reached high values by beginning period, decreasing thereafter due its oxidation, mainly sulphate. Based these results a period least months is required fall safe levels point view biological toxicity. Total phosphorus removal low, 9–33%; soluble orthophosphate concentrations remained virtually unchanged, especially when initial organic loading high.