Biofuels production 179
Figure 4.15 Packing media for anaerobic filters: (a) pall ring; (b) crossflow media; (c)
tubular media
Table 4.12 Packing media for anaerobic filters (Henze and Harremoes 1983)
Material Characteristics
Specific
surface
area (m^2 /m^3 )
Empty bed
porosity
Quartz stone
Granite stone
Lime stone
Gravel
Oyster shells
Active carbon
Red clay blocs
Corrugated blocs
PVC
Granite chips
Pall rings
Norton plastic rings
Rachig rings
Polypropylene spheres
20-40 mm dia.
25-38 mm dia.
20-40 mm dia.
6-38 mm dia.
60-100 mm dia.
1.5 mm dia.
28.28 mm pore size
25 mm dia.
12-25 mm
90.90 mm
90 mm
10.16 mm
90 mm dia.
157
98-132
102
114
45-49
89
0.42
0.53
0.49
0.4
0.82
0.60
0.7
0.95
0.40
0.95
0.95
0.76-0.78
>0.95