Others cases

In general, all types of wastewater can be used as substrates as long as they contain carbohydrates, proteins, fats, cellulose and hemicelluloses as main components. It is important that the following points are taken into consideration when selecting the wastewater industrial.

The content of organic substance should be appropriate for the microorganisms selected in anaerobic process. [12]

in the bioreactor depends on the origin of the liquid. In the Table 8, is shows the methane production rate from wastewater of different types.

Wastewater

type

Reactor

Type

HRT

(days)

OLR

(kg COD/m[13] [14] [15] [16] [17]-d)

Temperature

(°C)

COD

removed

(%)

MPR

(m3CH4/kg

COD)

Ref.

Slaughter­

house

Anaerobic

filter

0.6-3.0

3.7 -16.5

25

50-81

0.41

[1] *

Slaughter­

house

CSTR

20-30

0.2-0.3

37

70-80

0.45

[2] *

Tequila

vinasses

UASB

2.0-2.5

2.0-12.0

37

50-85

0.46

[3] *

Cane

vinasses

CSTR

20-30

2.5-12.7

35

50-75

0.42

[4] *

Pulping

coffee

CSTR

20-30

0.2-0.4

35

60-75

0.37

[5] *

Table 8. Methane production rate from wastewater of different type

In all previous cases, the wastewaters are discharged directly into the body of water,

causing several environmental pollution in addition to the loss of the energetic potential

contained in the effluents.