ANAEROBIC TREATMENT OF PHENOL IN A CONTINOUS FLUIDIZED-BED BIORREACTOR
Special Symposium - Environmental Protection & Sustainability
Environmental Protection & Sustainability (EPS - Poster)
Keywords: biodegradation, anaerobic treatment, fluidized-bed biorreactor, phenol
Gonzalo, M.S., Martínez, M. and Letón, P.
Chemical Engineering Department. Science Faculty. Alcalá University 28871. Alcalá de Henares. Madrid.Spain. E-mail: mgm04492@alu.uah.es
In anaerobic digestion most of the organic compounds are degrade by the action of a wide variety of microrganisms (usually bacteriums) in oxygen absence and other oxidant agents. CH4 and CO2 are the most significant products of degradation [1].
Phenol is a common pollutant of many industrial effluents from chemical operations. In this study, degradation of phenol has been done in a fluidized-bed bioreactor (RALF) [2] by the addition of increasing concentrations next to the feeding point.
A mixture of acetic, propionic and butyric acids -2:1:1 until 500 ppm in TOC- were used as the only source of carbon to feed the reactor. Macro and micronutrients were supported in relation 100:7:1 in C:N:P, and its composition was based in the use of Evans minimum middle. Next was increased the phenol concentration until 600 ppm. During de continuous period, the reactor was feeded with a synthetic wastewater, varying the TOC concentration from 500 ppm until 1100 ppm with 6 hours of hydraulic retention time.
It was measured the feeding flow (L/day), gas flow (L/day) gas composition [CH4 and CO2 (mM) by gas chromatography GC-TDC] and influent-effluent composition (acids and phenol by gas chromatography GD-FID and TOC in a TOC Analyzer).
Removal efficiency of acid degradation was about 90% in TOC and DQO, sometimes 100% with 6 hours of hydraulic retention time. TOC evolution shows three stages corresponding to the start-stage of the reactor, a stationary phase and phenol incorporation to the feeding. Percents of final phenol degradation vary from 85% to 95%, getting smaller values when increasing its concentration. To obtain the kinetic constant of phenol degradation, it has been supposed a first order kinetic reaction, obtaining a result of 0.0012 L/mg•day.
Conclusions:
1. Fluidized-bed biorreactor shows high efficiency in phenol treatment, reaching removal efficiency until 100% sometimes, instead they usually vary from 85% to 95% (so high values considering 6 hours of time retention and a no-adapted sludge).
2. Illustration of kinetic reaction fits to a straight line, which shows the reaction occurs in a low-amount-zone of substrates, considering a first order reaction with K=0.0012 L/mg•day.
REFENCES
[1] H.H.P. Fang, D.W. Liang, T. Zhang and Y. Liu (2006). Anaerobic treatment of phenol in wastewater under thermophilic condition. Water Research, Volume 40, Issue 3, Pages 427-434.
[2] Speece R.E., (1996). Anaerobic biotechnology for industrial wastewaters. Archae Press, Nashville, USA.
See the full pdf manuscript of the abstract.
Presented Monday 17, 13:30 to 15:00, in session Environmental Protection & Sustainability (EPS - Poster) S-7P.
