Life Cycle Assessment of Biogas from Separated slurry

Table 5.1. Scenario G vs A: Contribution of the different processes to each environmental impact categories selected. Results, for each impact category, are expressed in % of the total positive contributions from the reference scenario (considering the 10 years values, when this applies). Soil JB3 (sandy)[1]

Impact Categories GW (10 y) GW (100 y) Acidifi-
cation
Eutrophi-
cation (N)
(10 y)
Eutrophi-
cation (N)
(100 y)
Eutrophi-
cation (P)
Ozone
formation
Respiratory
inorganics
Non-renewable
energy
Phosphorus
resources
SCENARIO A - cow
A.2 In-house storage 26.5 26.5 36.6 8.4 8.4 0.0 55.4 34.6 0.0 0.0
A.3 Outdoor storage - elect 0.9 0.9 0.2 0.0[a] 0.0[a] 0.0[a] 0.4 0.3 30.3 0.0[a]
A.3 Outdoor storage 18.2 18.2 10.7 2.6 2.6 0.0 39.0 13.3 0.0 0.0
A.4 Transport to field 1.0 1.0 0.7 0.1 0.1 1.2 1.9 2.7 40.7 0.0[a]
A.5 Field processes 53.4 62.4 51.8 88.9 104.2 98.8 3.3 49.1 29.0 0.0[a]
A.6 N fertiliser -10.0 -13.4 -9.9 -64.3 -71.2 -2.1 -7.0 -15.0 -211.3 0.0[a]
A.6 P fertiliser -1.3 -1.3 -3.3 -0.1 -0.1 -138.4 -1.5 -5.3 -60.8 -99.9
A.6 K fertiliser -0.9 -0.9 -0.4 -0.1 -0.1 -0.9 -1.0 -1.2 -40.0 -0.1
Sum of positive contributions 100 109 100 100 115 100 100 100 100 0.0[a]
Sum of negative contributions -12 -16 -14 -64 -71 -141 -10 -22 -312 -100
SCENARIO G
G.2 + G.11 In-house storage 26.5 26.5 36.6 8.4 8.4 0.0 55.4 34.6 0.0 0.0
G.3 + G.12 Pre-tank storage 0.4 0.4 0.1 0.0[a] 0.0[a] 0.0[a] 0.2 0.1 14.5 0.0[a]
G.4 Separation – elect & equipment 0.3 0.3 0.1 0.0[a] 0.0[a] 0.0[a] 0.1 0.1 8.8 0.0[a]
G.4 Polymer for separation 0.1 0.1 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.1 0.0[a] 4.4 0.0[a]
G.5 Outdoor storage liquid fraction 2.4 2.4 2.5 0.6 0.6 0.0[a] 4.6 3.1 4.1 0.0[a]
Transport (G.6, G.9, G.13, G.20, G.22, G.24, G.26) 1.7 1.7 1.1 0.2 0.2 1.4 3.5 4.0 72.7 0.0[a]
G.7 Field processes (liquid fraction) 6.3 7.8 11.7 21.7 24.6 14.6 0.9 11.3 9.6 0.0[a]
G.8 Storage fibre fraction on-farm 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.0[a] 0.1 0.0[a]
G.10 Storage fibre fraction biogas pl. 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
G.14 Storage raw slurry biogas plant 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
G.15 Biogas production 2.0 2.0 0.2 0.0[a] 0.0[a] 0.1 2.9 0.3 32.4 0.0[a]
G.16 Co-generation heat and power 19.1 19.1 8.0 2.3 2.3 0.1 32.4 19.2 5.0 0.0[a]
G.17 Avoided electricity production -18.7 -18.7 -4.6 -0.4 -0.4 -0.7 -9.0 -6.6 -641.1 0.0[a]
G.18 Avoided heat production -5.6 -5.6 -5.8 -0.3 -0.3 -0.9 -4.3 -7.4 -138.7 0.0[a]
G.19 Separation degassed mixture 0.4 0.4 0.1 0.0[a] 0.0[a] 0.0[a] 0.2 0.1 12.1 0.0[a]
G.21 Storage degassed fibre fraction 0.9 0.9 3.9 0.9 0.9 0.0[a] 0.9 3.6 0.6 0.0[a]
G.23 Field processes (degassed fibre fraction) 16.8 20.4 5.4 9.2 16.2 56.0 0.6 5.3 6.2 0.0[a]
G.25 Outdoor storage (degassed liquid fraction) 4.0 4.0 5.9 1.4 1.4 0.0[a] 7.7 6.8 6.0 0.0[a]
G.27 Field processes (degassed liquid fraction) 12.0 15.9 30.5 56.8 64.3 28.7 1.2 28.5 14.0 0.0[a]
G.28 N fertiliser – production & application on JB3 -10.0 -13.4 -9.9 -64.4 -71.3 -2.1 -7.0 -15.0 -211.5 0.0[a]
G.28 P fertiliser – production & application on JB3 -1.4 -1.4 -3.6 -0.1 -0.1 -149.6 -1.7 -5.8 -65.7 -108
G.28 K fertiliser – production & application on JB3 -1.2 -1.2 -0.5 -0.1 -0.1 -1.3 -1.4 -1.6 -54.5 -0.1
G.28 Yield changes -0.8 -1.3 -0.8 -3.7 -5.5 -2.8 -0.5 -1.1 -10.3 -1.4
Sum of positive contributions 93 102 106 102 119 101 111 117 190 0.0[a]
Sum of negative contributions -38 -42 -25 -69 -78 -157 -24 -38 -1122 -110

[1] The number of digits is not an expression of the uncertainty. All numbers are all rounded and accordingly, if the reader calculates the sum or the difference, it might vary slightly from the numbers shown in the table.

[a] This number is not a zero value.

 



Version 1.0 August 2010, © Danish Environmental Protection Agency