Verônica Marinho Fontes Alexandre

Pré-hidrólise enzimática da gordura de efluente da indústria de pescado objetivando o aumento da produção de metano

The application of solid lipase-rich enzymatic preparations (SEP) in the anaerobic treatment of industrial effluents from canned fish processing was investigated. SEP was produced by the fungus Penicillium simplicissimum through solid-state fermentation (SSF) of industrial wastes, and it was used in the hydrolysis of fats present in the effluents in order to facilitate the use of methane as a source of energy. The effluent (1500 mg O&G.L –1 ) was hydrolyzed with 0.2, 0.5 and 1.0% (w/v) of SEP at 30 °C for up to 18 hours. The effect of the enzymatic pre-treatment of O&G on the COD removal was not observed because regardless of the conditions adopted, values from 91 to 95% were obtained. The specific production of methane presented values that varied with the addition of SEP and time of hydrolysis. In the control experiments, in which the flasks were incubated at 30 o C without the addition of SEP, the specific methane production increased with the time of incubation reaching the maximum peak at 18h (138 mL CH 4 .g –1 COD consumed ). However, higher values of specific methane production were obtained with 0.5 and 1.0% of SEP highlighting the hydrolysis with 0.5% of SEP and 8 hours of hydrolysis with 216 mL CH 4 .g –1 COD comsumed . When comparing the control 0 hour (raw effluent) with the effluent hydrolyzed with 0.5% of SEP for 8 hours, it could be observed that the specific methane production increased by 2.7 times indicating that the substrate available for the action of anaerobic microorganisms were more easily assimilated.

Ammonia stripping, activated carbon adsorption and anaerobic biological oxidation as process combination for the treatment of oil shale wastewater

ABSTRACT Anaerobic biodegradability of oil shale wastewater was investigated after the following pretreatment sequence: ammonia stripping and activated carbon adsorption. Anaerobic biological treatment of oil shale wastewater is technically feasible after stripping at pH 11 for reducing the N-NH3 concentration, adsorption with 5 g/L of activated carbon in order to reduce recalcitrance and pH adjustment with CO2 so that the sulphate concentration in the medium remains low. After this pretreatment sequence, it was possible to submit the wastewater without dilution to an anaerobic treatment with 62.7% soluble chemical oxygen demand removal and specific methane production of 233.2 mL CH4STP/g CODremoved.