Anaerobic Treatment of Pharmaceutical Waste Fermentation Broth

The feasibility of anaerobic co-digestion of pharmaceutical waste fermentation broth (spent mycelia) mixed with pig slurry and corn-grass silage was studied. The waste broth proved very toxic to luminescent bacteria Vibrio fischeri (30 min EC50 = 1.19–3.35 vol. %) while it expressed lower toxicity to activated sludge (180 min EC50 = 4.11–15.32 vol. %). Initially, stabilization studies in aerobic and anaerobic conditions were performed to confirm feasibility of anaerobic degradation. A 30 L conventional mesophilic reactor was used for further digestion experiments. The control experiment (pig slurry and corn-grass silage only) with OLR of 1.5 kg m–3 d–1 achieved 70 % COD removal and methane production of 25.4 L d–1. The first experiment with added fermentation broth (OLR of 1.8 kg m–3 d–1) achieved 79 % COD removal and good methane production (30.9 L d–1). The second experiment with more fermentation broth (OLR of 2.2 kg m–3 d–1) failed after 20 days, but the system recovered when the OLR was reduced to 2.0 kg m–3 d–1. In the third experiment only pharmaceutical broth was used as a substrate. The process failed after 10 days of operation due to toxic shock. It has been concluded that the toxic impact could be avoided with an OLR not higher than 2.0 kg m–3 d–1, but at the same time pharmaceutical broth must not contribute more than 25 % to the total OLR

The relevance of bisphenol A adsorption during Fenton's oxidation

The aim of this research was to assess the efficiency of Fenton's oxidation for degradation of endocrine disruptor bisphenol A (BPA) with emphasis on extent of accompanying adsorption. Adsorption on the waste sludge resulting from the Fenton's oxidation could represent a significant impact on the final removal efficiency of BPA. Fenton's oxidation was accomplished at two con- centrations of BPA (0.228 and 22.8 mg L-1); both at the selected molar ratio of reagents Fe2+:H2O2(1:10), as a function of reaction time. The kinetics of adsorption of BPA on waste sludge was determined for the same two concentrations of BPA at two concentrations of waste sludge (0.1 and 6.0 g L-1). In addition to changing concentrations of BPA and sludge, the adsorption process was also influenced by parameters such as temperature, pH and contact time. Adsorption isotherms were determined. Oxidation and adsorption were monitored by gas chroma- tography combined with mass spectrum. It has been con- firmed that BPA is not completely oxidized in Fenton's oxidation, because it is adsorbed to formed waste ferric sludge and thus necessary precautions for sludge deposition must be observe