The study compared the performance of upflow anaerobic sludge blanket (UASB) reactors and anaerobic filters (AF) for the treatment of wheat straw washwater (WSW) which has a high concentration of Potassium ions. The trial was conducted at mesophilic temperatures (37 o C). The digesters were started up over a 48-day period using a synthetic wastewater feed and reached an organic loading rate (OL...

This work studied the influence of effluent recirculation upon the kinetics of anaerobic degradation of dairy wastewater in the feedless phase of intermittent upflow anaerobic sludge bed (UASB) reactors. Several laboratory-scale tests were performed with different organic loads in closed circuit UASB reactors inoculated with adapted flocculent sludge. The data obtained were used for determinati...

The present study was done to shorten the start-up time of up-flow anaerobic sludge blanket (UASB) reactor. Two different nutrients were used during the UASB start-up period, which was designed to decrease the hydraulic retention time (HRT) from 48 to 24 and 12 to 6 hrs at average temperatures of 25-34 oC. In the first stage, start-up was with glucose for 14 days and then the reactor was also f...

Propionate is an important intermediate product during the methane fermentation of organic matter, and its degradation is crucial for maintaining the performance of an anaerobic digester. In order to understand the effect of temperature on propionate degradation, an upflow anaerobic sludge blanket (UASB) reactor with synthetic wastewater containing propionate as a sole carbon source was introdu...

BACKGROUND During hydrous ethanol production from the sugar refinery industry in Mexico, vinasse is generated. Phenolic compounds and melanoidins contribute to its color and make degradation of the vinasse a difficult task. Although anaerobic digestion (AD) is feasible for vinasse treatment, the presence of recalcitrant compounds can be toxic or inhibitory for anaerobic microorganism. Therefore...

In order to upgrade the quality of anaerobically treated effluent to a level recommended for irrigation, integration of a UASB reactor with UV and AOPs (advanced oxidation processes) (Ozone, H2O2/UV, Fenton, and photo-Fenton) could be a better option for almost complete colour, COD removal, and disinfection of pathogens. High efficiency of the UASB can be maintained by proper process conditions...

Anaerobic treatment has many advantages over other biological method particularly when used to treat complex wastewater such as petroleum refinery wastewater. In this study two Up-flow Anaerobic Sludge Blanket (UASB) reactors were operated in parallel to treat six volumetric organic loads (0.58, 1.21, 0.89, 2.34, 1.47 and 4.14 kg COD/m·d) to evaluate the chemical oxygen demand (COD) removal eff...

Predation by protists is top-down pressure that regulates prokaryotic abundance, community function, structure, and diversity in natural and artificial ecosystems. Although the effects of predation by protists have been studied in aerobic ecosystems, they are poorly understood in anoxic environments. We herein studied the influence of predation by Metopus and Caenomorpha ciliates-ciliates frequ...

Resource recovery and reuse from domestic wastewater has become an important subject for the current development of sanitation technologies infrastructures. Different are available combined into concepts, with different performances. This study provides a methodological approach to evaluate sustainability these concepts focus on resource reuse. St. Eustatius, small tropical island in Caribbean,...

a model describing the main processes occurring in the uasb reactor was developed; in orderto maintain simplicity and applicability of the model, only the fundamental aspects were considered. in themodel, the reactor is divided in several well-stirred reactors coupled in series and it comprises substratedegradation, biomass growth and the reactions that take place within the granules. the impor...