Influence of temperature and pH on nitrogen removal in a series of maturation ponds treating anaerobic effluent.

This paper presents an evaluation of the influence of pH and temperature on nitrogen removal in a series of three shallow maturation ponds serving as post-treatment of upflow anaerobic sludge blanket (UASB) reactor effluent (approximately 200 population equivalent). Monitoring was from January 2007 to May 2009. Throughout this period, the ponds maintained relatively stable operational conditions in terms of depth and hydraulic retention time, thus enabling the evaluation of the influence of variations in temperature and pH on the performance in terms of nitrogen removal.

Importance of the ammonia volatilization rates in shallow maturation ponds treating UASB reactor effluent.

This study aimed at determining the influence of ammonia volatilization on nitrogen removal in polishing (maturation) ponds treating sanitary effluent from upflow anaerobic sludge blanket (UASB) reactors in the city of Belo Horizonte, Brazil. An apparatus for the capture and absorption of volatilized ammonia in three polishing ponds in series was installed. Volatilized ammonia was captured by a chamber on the surface of the ponds and dissolved in boric acid solution, in order to estimate the amount of ammonia per unit surface area of each pond.

Performance evaluation of a simple wastewater treatment system comprised by UASB reactor, shallow polishing ponds and coarse rock filter.

The work investigates a small full-scale wastewater treatment system comprised by the following units in series: UASB reactor, three polishing ponds and one coarse rock filter. The overall performance of the system is analyzed based on three years of monitoring using physical-chemical and biological parameters. Good organic matter, suspended solids and ammonia removal is achieved, together with excellent coliform removal (5.