up flow anaerobic sludge blanket (uasb) reactors have been increasingly used for industrial wastewater treatment. because of existing problems in startup step of these reactors, in this research the startup of a uasb in pilot scale and room temperature condition was studied. the total height of uasb reactor was 270 cm and effective height was 240 cm. diameter of the reactor in lower part was 20...

The mechanism of biomass granulation in anaerobic reactors has been widely studied in the hope that this could be helpful in manupulating the rate and extent of granule formation, particularly in wastewaters that show little intrinsic propensity to granulate (e.g. fat and oil containing effluents). Similarly, in this study, sets of sludge samples were taken from Normal Fed Anaerobic Baffled Rea...

The objective of this study was to determine the density anaerobic granules on different heights a full-scale Upflow Anaerobic Sludge Bed reactor. defined through settling velocities granules, measured in In study, granular calculated with and developed mathematical model. model is based Stokes experiment, were taken from an reactor, 0.6 7.6 m. granules’ diameters varied between 1 5 mm. six vel...

Anaerobic granulated biomass-based treatment is a sustainable alternative for municipal wastewater treatment. Each granule in the system comprised of complex community anaerobic microorganisms embedded biofilm matrix. The aim this work was to implement model simulation biogas production and COD removal as observed an experimental up-flow sludge blanket (UASB) reactor system. Additionally, selec...

Calcium is essential to the growth of several strains of microorganisms involved in anaerobic digestion. It has also been found to be effective in speeding up granulation of anaerobic sludges. But there are reports that the metal can exert a harmful effect on the performance of upflow anaerobic sludge blanket (UASB) reactor by causing the ‘cementing’ of some of the active sludge in the reactor,...

The influence of sludge age on granular sludge formation and microbial population dynamics in a methanol- and acetate-fed aerobic granular sludge system operated at 35°C was investigated. During anaerobic feeding of the reactor, methanol was initially converted to methane by methylotrophic methanogens. These methanogens were able to withstand the relatively long aeration periods. Lowering the a...

To monitor the granularity of anaerobic sludge, the determination of granule density is vital importance. Granular sludge is the key factor for the efficient operation of upflow anaerobic sludge blanket (UASB) reactor. For this reason several techniques have been proposed. In the proposed algorithm, the granular density was calculated. The granular density was strongly correlated with the VSS/T...

Performance of a high-rate anaerobic treatment system prior to and after the formation of granular sludge was investigated. The 500-L UASB pilot was set up to receive effluent from a medium-size traditional slaughterhouse without blood recovery. The system was inoculated with mesophilic municipal anaerobic digested sludge for the startup and was fed influent with a total COD in the range of 300...