Anaerobic filter

A third method of contact known as an anaerobic filter also uses upward flow but keeps the sludge in the digester by a physical barrier such as a grid. 

Anaerobic Filter. The anaerobic filter is similar to a trickling filter ia that a biofilm is generated on media. The bed is fully submerged and can be operated either upflow or downflow. For very high strength wastewaters, a recycle can be employed. 

Fig. 18. Anaerobic wastewater treatment processes (a) anaerobic filter reactor (b) anaerobic contact reactor (c) fluidized-bed reactor (d) upflow anaerobic...

The anaerobic filter, UASB, and fluidized bed reac tors have all been used for anaerobic treatment of industrial wastes, as each is especially suited for use in anaerobic treatment. Table 25-44 presents results from these applications. 

Modeling and simulation of anaerobic filter process two-dimensional distribution of acidogens and methanogens... 

Recently, anaerobic filter process has been widely used for the treatment of various waste-waters because of several advantages over aerobic process such as lower nutrient requirement, less surplus sludge production, and energy recovery via methane production [1]. Although many types of anaerobic filter process have already been successfully commercialized, the details of their complicated process dynamics are still challenging issues to be clarified for their stable operations. 

Details of the mathematical model to describe anaerobic filter process Model parameters and variables... 

Although the presented model could describe the anaerobic filter process more reasonably, it has still some limitations such as the fixed thickness and the fixed overall density of the... 

Guerrero, L., Omil, F., Mendez, R., and Lema, J.M., Treatment of saline wastewaters from fish meal factories in an anaerobic filter under extreme ammonia concentrations, Biores. Technol., 61, 69-78, 1997. 

AF Anaerobic filter, AFBR Anaerobic fluidized bed reactor, UASB Up-flow anaerobic sludge blanket reactor, COD Chemical oxygen demand, HRT Hydraulic retention time. 

Mustapha, S., Ashhuby, B., and Azni, I., Start-up strategy of a thermophilic upflow anaerobic filter for treating palm oil mill effluent, Process Safety and Environmental Protection, 81 (4), 262-266, 2003. 

Siino, F.J., Blanc, F.C., and O shaughnessy, J.C., Performance of an anaerobic filter treating soluble carbohydrate waste, 40th Annual Purdue Industrial Waste Conference, pp. 785-793, 1985. 

Anaerobic reactor types 1, up-flow anaerobic sludge bed 2, anaerobic fluidized bed 3, anaerobic filter 4, anaerobic rotating disc 5, inclined tubular digester (6, pre-acidification tank)... 

In many cases, anaerobic filter treatment was found to successfully treat pharmaceutical industry wastewater. This can be an excellent alternative for conventional aerobic treatment, which is energy intensive and requires the disposal of sludge. The anaerobic filter, on the other hand, can produce energy in the form of biogas and does not require... 

Gallagher, A., et al. Pharmaceutical waste disposal. Sewage Ind. Waste 1954, 26 (11), 1355-1362. Seeler, T.A. Jennet, J.C. Treatment of wastewater from a chemically s)mthesized pharmaceutical manufacturing process with the anaerobic filter. Proceedings of the 33rd Industrial Waste Conference, Purdue University, West Lafayette, IN, 1978, 687-695. 

Jennet, J.C. Dennis, N.D. Anaerobic filter treatment of pharmaceutical waste. J. Water Pollut. Conf. 1975, 47 (1), 104-121. 

Anaerobic reactor configurations that have found application in the treatment of pulp and paper mill effluent include anaerobic contact, UASB, anaerobic filter, UASB/AF hybrid, and fluidized bed reactors. Specific features of these reactors are described in the following sections. 

Anaerobic Filter. An anaerobic filter consists of packed support media that traps biomass as well as facilitates attached growth of biomass as a biofilm (Fig. 8). Such a reactor configuration helps in the retention of suspended biomass as well as gas-liquid-solid separation. The flow of liquid can be upward or downward, and treatment occurs due to attached and suspended biomass. Treated effluent is collected at the bottom or top of the reactor for discharge and recycling. Gas produced in the media is collected underneath the bioreactor cover and transported for storage or use. Volumetric loading rates vary from 5 to 20 kg COD/m day with HRT values of 0.5-4 days. 

Figure 8 Diagrammatic representation of anaerobic filter process (from Ref. 77).

Rotating biological contactor Trickling filter Packed bed Anaerobic filter... 

Wu YC, Hao OJ, Ou KC, Schoelze RJ (1988), Treatment of leachate from solid waste landfill site using a two-stage anaerobic filter, Biotechnol. Bioeng. 31 257-266. 

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