Activated Carbon Anaerobic Reactor Research Articles

Application of biological activated carbon anaerobic reactor for treatment of hazardous chemicals

An expanded-bed anaerobic reactor with granular activated carbon (GAC) medium has been developed to treat wastewaters that contain a high concentration of inhibitory and/or refractory organic compounds as well as readily degradable organic compounds. The process is characterised by a combination of two removal mechanisms; adsorption on GAC and biological degradation by microorganisms grown on GAC. Applicability of the reactor to treatment of phenol, chloroacetaldehyde (CAA), pentachlorophenol (PCP) and tetrachloroethylene (PCE) was discussed based on experimental data. All chemicals focused on here were removed well and stably at a removal efficiency of more than 98% even during starting operation and shock load operation. Chemicals in influent that exceeded biological degradation capacity was initially adsorbed on GAC and then gradually degraded, and hence the adsorptive capacity of GAC was regenerated biologically. These results proved that a biological activated carbon anaerobic reactor was effective for treatment of wastewater containing hazardous chemicals, especially for strongly absorbable chemicals, as well as readily degradable organic compounds at high concentration.

Kinetics of Methanogens in an Expanded‐Bed Reactor

A biofilm mathematical model for single-stage substrate utilization was developed for an expanded-bed, activated-carbon anaerobic reactor. The concepts of liquid-layer mass transport, biofilm molecular diffusion, and Monod kinetics were incorporated into the model. During 849 days of continuous operation, four steady state operating conditions were obtained, covering a wide range of feed acetate concentration. Steady state data collected when the feed acetate concentrations were 1,600 mg/L and 3,200 mg/L and weekly data obtained when the feed acetate concentration was 6,400 mg/L were used to estimate biokinetic parameters. The model input for each data set consisted of the acetate flux and the log-mean bulk acetate concentration within the reactor. The model was solved for attached biomass using each data set and various trial values of the two Monod constants, k\da, K\ds\da, and a microbial biofilm density, X\da\df. Best estimates of k\da, and X\da\df were obtained by observing the lowest value of the minimum sum of squared deviations between the model-predicted biomass and measured biomass. The biofilm kinetics were characterized as fully penetrated, with no significant external mass transport resistance.