Developing Inoculum to Increase Anaerobic Digestion Efficiency in
Winter Months.
NESARE Project (GNE11-030) Annual Report 2012
Appendix B
Cumulative Methane (mL CH4/mL soil)
Cumulative Methane for the SMA Tests
on the 4 Wetland Sites
0.8
0.7
0.6
0.5
Site 1 Soil
0.4
Site 2 Soil
0.3
Site 3 Soil
0.2
Site 4 Soil
0.1
0
-0.1
0
5
10
15
20
25
Days
Figure 1: Cumulative methane (mL CH4/mL soil) for the specific methanogenic
activity (tests) conducted on soils from 4 wetland sites, where:
Site 1: A tidal freshwater marsh located within the Jugbay Wetland Sanctuary
adjacent to the Patuxent River, Maryland, USA (approximate coordinates:
38°46'51.36"N, 76°42'26.61"W).
Site 2: A tidal freshwater marsh located within the Jugbay Wetland Sanctuary
adjacent to the Patuxent River, Maryland, USA (approximate coordinates:
38°46'49.63"N, 76°42'45.75"W).
Site 3: A beaver pond located within the Patuxent Wetland Park, in close proximity
to the Jugbay Wetland Sanctuary, and adjacent to the Patuxent River, Maryland, USA
(approximate coordinates: 38°48'34.99"N, 76°42'33.48"W).
Site 4: Open water pond located in a housing community in Culvert County,
Maryland, USA (approximate coordinates: 38°44'45.94"N, 76°40'52.05"W).
Percent Methane Changes During the
SMA Tests for Various Landfill Leachates.
Percent Methane in SMA Bottles' Headspace
3.5
3
Leachate from Stafford
County Landfill (Virginia,
USA)
2.5
Leachate from Corral Farm
Landfill (Virginia, USA)
2
Leachate from Parkton
Landfill (Maryland, USA)
1.5
Leachate from Charles
County Landfill (Maryland,
USA)
1
0.5
Leachate from Eastern
Sanitary Landfill
(Maryland, USA)
0
0
10
20
30
Days
Figure 2: Changes in headspace percent methane during specific methanogenic
methane (SMA) tests of landfill leachates obtained from 5 different locations.
Figure 3: Reactors (approximately 4L in volume) were constructed to incubate the
inocula from various sources.
Cumulative Methane During the
Incubation of Inocula at 15°C
Cumulative methane (mL/g VS)
200
180
160
BARC Digestate
140
Wetland Site 1 Soil
120
100
Wetland Site 2 Soil
80
60
Stafford County Landfill
Leachate
40
20
Charles County Landfill
Leachate
0
0
20
40
60
80
100
Days
Figure 4: Cumulative methane (mL/g of volatile solids (VS)) measured during the
incubation of inocula (wetland site 1 (approximate coordinates: 38°46'51.36"N,
76°42'26.61"W) soil, wetland site 2 (approximate coordinates: 38°46'49.63"N,
76°42'45.75"W) soil, Stafford County landfill leachate, Charles County landfill
leachate, and Beltsville Agricultural Research Center (BARC) anaerobic digestate) at
15°C.
Cumulative methane (mL/g of VS)
400
Cumulative Methane During the
Incubation of Inocula at 25°C
350
300
BARC Digestate
250
Wetland Site 1 Soil
200
Wetland Site 2 Soil
150
Stafford County Landfill
Leachate
100
50
Charles County Landfill
Leachate
0
0
20
40
60
80
100
Days
Figure 5: Cumulative methane (mL/g of volatile solids (VS)) measured during the
incubation of inocula (wetland site 1 (approximate coordinates: 38°46'51.36"N,
76°42'26.61"W) soil, wetland site 2 (approximate coordinates: 38°46'49.63"N,
76°42'45.75"W) soil, Stafford County landfill leachate, Charles County landfill
leachate, and Beltsville Agricultural Research Center (BARC) anaerobic digestate) at
25°C.
Cumulative Methane During the
Incubation of Inocula at 35°C
Cumulative methane (mL/g VS)
450
400
350
BARC Digestate
300
Wetland Site 1 Soil
250
200
Wetland Site 2 Soil
150
Stafford County Landfill
Leachate
100
50
Charles County Landfill
Leachate
0
0
20
40
60
80
100
Days
Figure 6: Cumulative methane (mL/g of volatile solids (VS)) measured during the
incubation of inocula (wetland site 1 (approximate coordinates: 38°46'51.36"N,
76°42'26.61"W) soil, wetland site 2 (approximate coordinates: 38°46'49.63"N,
76°42'45.75"W) soil, Stafford County landfill leachate, Charles County landfill
leachate, and Beltsville Agricultural Research Center (BARC) anaerobic digestate) at
35°C.
Cumulative Methane for the Third Month
BMP Test at 15°C
Cumulative Methane (mL/g of Manure)
1.20
1.00
50% Landfill Leachate
35% Landfill Leachate
0.80
20% Landfill Leachate
Manure Only
0.60
50% Wetland Soil
35% Wetland Soil
0.40
20% Wetland Soil
50% BARC Digestate
0.20
35% BARC Digestate
20% BARC Digestate
0.00
0
20
40
60
80
100
Days
Figure 7: Cumulative Methane (mL/g Manure) for the biochemical methane
potential (BMP) test conducted at 15°C using various types inocula (wetland site 1
(approximate coordinates: 38°46'51.36"N, 76°42'26.61"W) soil, Stafford County
landfill leachate, and Beltsville Agricultural Research Center (BARC) anaerobic
digestate) that had been previously incubated for three months at 15°C and differing
inoculum to substrate ratio (50% (w/w), 35%, 20%, and 0%). Values are average of
replicates.
Cumulative Methane for the Third Month
BMP Test at 25°C
Cumulative Methane (mL/g of Manure)
30
25
50% Landfill Leachate
35% Landfill Leachate
20
20% Landfill Leachate
50% Wetland Soil
15
35% Wetland Soil
20% Wetland Soil
10
50% BARC Digestate
35% BARC Digestate
5
20% BARC Digestate
Manure Only
0
0
20
40
60
80
100
Days
Figure 8: Cumulative Methane (mL/g Manure) for the biochemical methane
potential (BMP) test conducted at 25°C using various types inocula (wetland site 1
(approximate coordinates: 38°46'51.36"N, 76°42'26.61"W) soil, Stafford County
landfill leachate, and Beltsville Agricultural Research Center (BARC) anaerobic
digestate) that had been previously incubated for three months at 25°C and differing
inoculum to substrate ratio (50% (w/w), 35%, 20%, and 0%). Values are average of
replicates.
Cumulative Methane for the Third
Month BMP Test at 35°C
Cumulative Methane (mL/g of Manure)
30
25
50% Landfill Leachate
35% Landfill Leachate
20
20% Landfill Leachate
Manure Only
15
50% Wetland Soil
35% Wetland Soil
10
20% Wetland Soil
50% BARC Digestate
5
35% BARC Digestate
20% BARC Digestate
0
0
20
40
60
80
100
Days
Figure 9: Cumulative Methane (mL/g Manure) for the biochemical methane
potential (BMP) test conducted at 35°C using various types inocula (wetland site 1
(approximate coordinates: 38°46'51.36"N, 76°42'26.61"W) soil, Stafford County
landfill leachate, and Beltsville Agricultural Research Center (BARC) anaerobic
digestate) that had been previously incubated for three months at 35°C and differing
inoculum to substrate ratio (50% (w/w), 35%, 20%, and 0%). Values are average of
replicates.