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Biomedical subjects

G Massarani

Publications and source records attributed to G Massarani.

7 recordsLinked to original sources
PubMed2004

Comparative study of flotation techniques for the treatment of liquid effluents.

This work aimed to study the performance of three different induced air flotation units (flotation column, flotation tank and centrifugal flotation in hydrocyclone) for the treatment of a synthetic dairy effluent. Under continuous operation, it was possible to achieve removal efficiencies of milky material in suspension up to 90%, both for the flotation column and the flotation tank units. Using the centrifugal flotation unit in hydrocyclone, it was possible to decrease up to 45% of all suspended material in the effluent, with a clarified flow rate approximately three times greater than those found for the previous flotation units. In the centrifugal flotation unit, better results were obtained for air flow rate-feed flow rate ratios (Q(air)/Q(L)) greater than 0.15, and for underflow-overflow ratios (Qu/Qo) lower than 1.0.

Air↗
PubMed2003

Flotation techniques for oily water treatment.

The aim of this work is to develop alternative techniques for the treatment of waters heavily contaminated by oil. Furthermore, the treatment system should achieve high removal efficiencies even under unfavorable conditions, when oil is finely dispersed in the water phase and oil droplet sizes range from 5-30 mm and concentrations are between 100 and 300 mg l(-1). The first experiments were carried out in an induced air flotation system where a flotation column performance was evaluated in batch and continuous operation. The second system investigated in this work focused on the association of centrifugal separation in a hydrocyclone and the flotation operation. The considered system is characterized by the association of these two processes, resulting the set-up in a compact unit (centrifugal flotation system). The bubbles generation and the droplet-bubble contact are performed through a gas-liquid ejector, while the separation of the phase rich in oil (froth phase) is promoted by a hydrocyclone. In both systems, it was possible to reduce the chemical demand of oxygen by more than 85% and the oil concentration of an emulsion containing droplets with sizes between 10 and 20 mm, using Polyacrilamide as destabilizing agent.

Gases↗
PubMed2002

Recovery of Bacillus sphaericus 2362 spores from growth medium by flocculation/sedimentation.

Bacillus sphaericus 2362 spore sedimentation was evaluated through batch settling experiments, using tannin as the flocculating agent. The flocculation was demonstrated to be efficient up to the tannin concentration of 150 ppm. The floc diameter averaged 208 micro m, and its density was found to be 1.09 g/mL. The sedimentation process using tannin as a flocculating agent is promising, and a spore concentrate was obtained without loss of biological activity, presenting a LC(50) equal to 0.22 ppm. The result indicates that the larvicide activity is appropriate for controlling populations of Culex quinquefasciatus.

Journal Article↗
PubMed2000

Influence of the flocculating agent in sedimentation and performance of a non flocculent strain of Zymomonas mobilis in the ethanol production process.

The influence of the flocculating agent was studied in the performance (measured by microbial growth and ethanol production) of a non flocculent strain of Zymomonas mobilis, as well as the potentiality of the sedimentation process in the separation of the biomass from the fermentation broth. Among the flocculating agents studied, it was verified that both tannin and the polyelectrolyte yielded good results with regard to cellular performance. However, with regard to sedimentation tannin is more adequate to be used in processes involving Zymomonas mobilis.

Acrylic Resins↗