Przytocka-Jusiak M

Intensive culture of Chlorella vulgaris/AA as the second stage of biological purification of nitrogen industry wastewaters

Abstract A method for the two-stage removal of nitrogen from highly loaded nitrogenous wastewaters carrying varying proportions of nitrates, nitrites and ammonium is presented. The method combines denitrification (stage 1 of purification) and intensive algal culture (stage II of purification). Denitrification in an anaerobic packed bed reactor removed all the oxidized forms of nitrogen from the wastes enriched in methanol and phosphorus. Ammonium remaining in the denitrified wastewaters was removed by intensive culture of algae. The use of this method resulted in 94.0–99.9% removal of nitrogen from the wastes. The application of the proposed method is limited, however, by the concentration of ammonium nitrogen in the wastewaters.

Removal of nitrogen from industrial wastewaters with the use of algal rotating disks and denitrification packed bed reactor

Abstract An attempt was made to use an algal rotating disk system in a two-step biological purification of nitrogen fertilizer industry wastewaters. The proposed method involved the removal of ammonium by Stichococcus bacillaris growing on the rotating disk and of oxidized forms of nitrogen by denitrifying bacteria. The use of a rotating algal disk followed by denitrification bed as the second step of biological treatment removed about 90% of nitrogen from the wastewater. A change of purification sequence resulted in the appearance of NO −3 and NO−2 in the purified wastewater caused by the activity of nitrifying bacteria accompanying algae in the biological film on the disk. It was found that methanol used as a carbon source for denitrifying bacteria could be replaced by organic matter of algal origin.

Cadmium removal by green alga Stichococcus bacillaris

Abstract Cadmium removal by S . bacillaris cells was investigated. At constant biomass density 1 g of dry weight/1 - 60 %–80% of cadmium was removed by algae from the solutions containing to 4 mg Cd/1. The extent of cadmium removal was alga suspension density dependent. Quadruple usage of new algae (of density 1 g dry weight/1) in the solutions containing 0.5 and 4.0 mg of Cd/1 caused cadmium removal in 96%.