Comparison of the Purifying Efficiency of High Rate Algal Pond with Stabilization Pond

Abstract

Due to its high sanitary efficiency, treatment of wastewater by Stabilization Ponds (SP) is proposed for sensitive coastal areas (proximity to bathing areas, shellfish farming lagoons). This process, suitable for small communities with high summer populations, requires a large surface area. The objective of this study is to compare High Rate Algal Pond (HRAP) purifying efficiency with that of SP. We have experimented with a HRAP process, which by generating algal growth reduces the required surface area; our studies suggest this to be by a factor of 5. This process is particularly interesting for nutrient removal, especially nitrogen, and could be useful in coastal areas susceptible to eutrophication. Its sanitary performance is comparable to that of SP. Environmental factors and pond depth play a more important role in HRAP efficiency than retention time of water in the basins.

Dual role of microalgae: Phycoremediation of domestic wastewater and biomass production for sustainable biofuels production

“…Biofuel production in conjunction with wastewater treatment and fertiliser recycling is seen as a near-term application (5-10 years), since the algae are already used in wastewater treatment (Table 3) [72]. The HRAP showed remarkable performance and behaviour when compared to a series of three facultative ponds such as anaerobic, aerobic and alternative constructed facultative ponds on the same site by receiving the same sewage [73]; see also [74]. The HRAP is a photosynthetic reactor in which microscopic, photosynthetic algae live together with heterotrophic bacteria which degrade the sewage organic matter.…”

Variations saisonnières des formes de phosphores dans une station de traitement des eaux usées par lagunage, sous climat aride de Marrakech (Maroc)

“…En France, MARTIN (1987), a décrit un rendement moyen de 53 % dans une vingtaine de stations d'épuration par lagunage, RACAULT et al, (1995) à partir de 160 stations, donnent un taux d'élimination moyen du phosphore de 57 %. PICOT et al, (1992) trouvent un rendement d'élimination du phosphore de 19,5% seulement dans le bassin de lagunage de Mèze, sous climat méditerranéen, au sud de la France.…”

Plankton biomass in secondary ponds treating piggery waste

“…The highest concentration was at the bottom of the HRAP and MP1 and on the surface of MP2 and WHP, near the average values obtained by Oliveira (2002) with piggery waste (2,608 µg/L).During the day, some algae changed in the liquid mass and selected the depth where the light intensity was more adequate to photosynthesis (König, 2000). Picot et al (1992) obtained, in domestic effluents treated in HRAP, chlorophyll a of 2,000 µg/L, in the sunny and hot months in the Mediterranean region, with the same temperature (17.2ºC). Bassères (1990) obtained chlorophyll a of 2,855 µg/L, with piggery waste treated in the HRAP (COD soluble of 1,351 mg/L).…”