RESUMO
Background: In this study, the effect of wastewater produced by pistachio processing in processing terminals on wastewater treatment plants with activated sludge process was investigated
Methods: The pilot of activated sludge was constructed at the laboratory scale similar to wastewater treatment plant in Kerman and it was investigated in different ratios of the wastewater of pistachio processing with urban wastewater and return sludge ratios of 50% and 75%. The best reactor efficiency in treating pistachio processing wastewater was obtained at a ratio of 5% with urban wastewater and return sludge of 50% plus 5 and 10% with urban wastewater and return sludge of 75%
Results: The removal efficiency in the reactor in the aforementioned ratios was obtained to be 96.9%, 98%, and 96.2% for COD, 95.7%, 97.2%, and 93.3% for BOD5, and 7.1%, 99%, and 96.97% for phenolic compounds, respectively. The removal efficiency of BOD5 and COD reduced with the increase in the ratios of pistachio processing wastewater especially with the presence of phenolic compounds. The one-way analysis of variance [ANOVA] indicated that in the aforementioned ratios of pistachio processing wastewater with urban wastewater, the mean COD and BOD5 in the output wastewater were significantly lower than the standards of Iranian environmental organization and guidelines of World Health Organization [WHO]
Conclusion: Activated sludge process is able to remove organic compounds of pistachio processing wastewater at a ratio of 5% and return sludge of 50% along with ratios of 5 and 10% and return sludge of 75% with urban wastewater with a high efficiency
RESUMO
Background: Antibiotics are important pollutants of water resources, and because of hard biodegradability, they can be filtered through adsorption method. Activated carbon is one of the best adsorbents. The aim of this study was to investigate the amoxicillin removal rate of a standard granular activated carbon
Materials and methods: The adsorption experiments were conducted in the stirred [100 rpm] glass reactor. In each test, 50 ml of aqueous solution contaminated by amoxicillin was transferred into the reactor, and the influence of adsorbent dose, adsorbent type, amoxicillin concentration, reaction time, solution pH and temperature was tested on the amoxicillin adsorption. At the end of each of adsorption tests, the suspension was filtered using a cellulose acetate filter with 0.45?m pore size and the filtrate was analyzed for residual amoxicillin using HPLC
Results: The obtained data showed that the best conditions for removal of amoxicillin from contaminated water using granular activated carbon were as follow: pH: 6, adsorbent concentration: 1.6 g/l, reaction time: 60 min, temperature: 25oc. In these conditions up to 86% of amoxicillin [concentration: 50 mg/l] could be adsorb by a granular 16-20 activated carbon
Conclusion: Adsorption onto activated carbon is an efficient method for the removal of non-degradable water pollutants such as antibiotics and toxins
RESUMO
Formaldehyde is used in many industrial applications as raw material and therefore high concentrations are found in their effluents. Activated sludge processes based on biofilm growth are increasingly used because of appreciate abilities in controlling of high organic load industrial effluents. The main objective of this study was to determine the effect of biofilm in improvement of activated sludge efficiency for treatment of industrial effluents containing formaldehyde. Two lab scale activated sludge reactors [with and without fixed bed for biofilm growth] were investigated in organic loading rate of 0.7-10.5 kgCOD/m3.d, aerobic condition and the room temperature. In this study, the effects of organic and hydraulic loads were investigated for the mentioned two processes. The most COD removal efficiency for biofilm activated sludge was 98.86%. The reactor containing biofilm had removal efficiency of more than 64% up to the organic loading rate of 10.5 kgCOD/m3.d, while the conventional activated sludge reactor collapsed in organic loading rate of 7.5 kgCOD/m3.d. Findings of this study indicate that activated sludge reactor containing fixed bed for biofilm growth is significantly more efficient than the conventional activated sludge one