Evaluation of the effect of the feeding regime on the removal of metals and pathogens in microalgae-bacterial systems.

Microalgae-bacteria systems are used for the treatment of effluents, using a technology that has stood out with excellent results, as reported in the literature. However, investigating these systems in more depth can improve our understanding of the removal mechanisms for a wide range of existing and emerging pollutants and help improve the guidelines for design and operation, in order to improve the treatment efficiency as well as biomass productivity. This work studied the impact of the feeding regime on the removal of metals and pathogens from primary domestic wastewater in high rate algal ponds (HRAPs).

Influence of the hydraulic retention time on the removal of emerging contaminants in an anoxic-aerobic algal-bacterial photobioreactor coupled with anaerobic digestion.

This work evaluated, for the first time, the performance of an integral microalgae-based domestic wastewater treatment system composed of an anoxic reactor and an aerobic photobioreactor, coupled with an anaerobic digester for converting the produced algal-bacterial biomass into biogas, with regards to the removal of 16 contaminants of emerging concern (CECs): penicillin G, tetracycline, enrofloxacin, ciprofloxacin, sulfamethoxazole, tylosin, trimethoprim, dexamethasone, ibuprofen, naproxen, acetaminophen, diclofenac, progesterone, carbamazepine, triclosan and propylparaben. The influence of the hydraulic retention time (HRT) in the anoxic-aerobic bioreactors (4 and 2.5 days) and in the anaerobic digester (30 and 10 days) on the fate of these CECs was investigated.

Chlorella vulgaris growth on anaerobically digested sugarcane vinasse: influence of turbidity.

This paper shows the influence of turbidity (in Nephelometric Turbidity Units - NTU), chemical oxygen demand (COD) and aeration (CO2 supply) on the productivity and growth rate and lipid content of microalgae (a mixed culture predominantly composed of Chlorella vulgaris), using anaerobically digested vinasse as a culture medium. The microalgae can be cultivated in anaerobically digested vinasse, at turbidity and chemical oxygen demand of 690 NTU and 2.5 gCOD L -1, respectively, according to the modified Gompertz model, and removal of turbidity by filtration did not influence the microalgae productivity (≈ 77 mg L1 d1).

The effect of CO addition and hydraulic retention time on pathogens removal in HRAPs.

The influence of CO addition and hydraulic retention time (5 and 7 days) on removal of Pseudomonas aeruginosa, Clostridium perfringens, Staphylococcus sp., Enterococcus sp., and Escherichia coli was evaluated in a system with three parallel 21 L high rate algal ponds.

Surfactant removal and biomass production in a microalgal-bacterial process: effect of feeding regime.

The influence of the feeding regime on surfactant and nutrient removal and biomass production was evaluated in three high rate algal ponds for primary domestic wastewater treatment. Feeding times of 24, 12 and 0.1 h d were studied in each reactor at a similar hydraulic retention time of 7.

Evaluation of biomethanization during co-digestion of thermally pretreated microalgae and waste activated sludge, and estimation of its kinetic parameters.

The maximum methane yield that can be obtained from anaerobic co-digestion of microalgae and waste activated sludge (WAS) mixtures, after thermal pretreatment at 65 °C during 4 h, was investigated. Furthermore, the fitting of the experimental data by five kinetic models (first-order, second-order, modified Gompertz, Logistic, and two-substrate) was evaluated. Thermal pretreatment increased the methane yield of single microalgae and WAS digestion by ≈ 44 and by ≈ 52%, respectively.

Influence of biogas flow rate on biomass composition during the optimization of biogas upgrading in microalgal-bacterial processes.

The influence of biogas flow rate (0, 0.3, 0.6, and 1.