. 2018 May 17;8:7786. doi: 10.1038/s41598-018-26141-w

Table 2.

Average removal and the economic efficiency of biogas CO₂ and biogas slurry nutrient reduction under the three CO₂ concentrations.

Five strains/CO₂ concentration treatments	Removal efficiency (%)				Economic efficiency (USD⁻¹)
Five strains/CO₂ concentration treatments	COD	TN	TP	CO₂	COD	TN	TP	CO₂
CO₂ 35% (v/v)
P. geesteranus/C. vulgaris	57.37 ± 4.02^a	48.53 ± 4.24^b	51.29 ± 3.62^b	54.15 ± 4.12^a	29.56 ± 1.92^ab	20.25 ± 1.75^b	27.35 ± 2.16^b	26. 35 ± 2.34^a
G. lucidum/C. vulgaris	60.52 ± 4.71^a	58.15 ± 4.79^a	59.37 ± 4.16^a	57.18 ± 4.33^a	31.24 ± 2.21^a	29.98 ± 2.04^a	30.34 ± 2.35^a	28.19 ± 2.57^a
P. ostreatus/C. vulgaris	51.72 ± 3.65^b	46.84 ± 3.22^bc	49.35 ± 3.25^b	49.22 ± 3.68^b	27.96 ± 2.06^b	19.41 ± 1.62^b	21.32 ± 1.73^c	22.68 ± 1.91^b
G. lucidum/S. obliquus	50.53 ± 3.24^b	59.71 ± 4.83^a	57.64 ± 4.37^a	47.43 ± 3.95^b	26.35 ± 1.88^b	30.67 ± 2.13^a	28.51 ± 2.24^ab	20.54 ± 1.79^b
G. lucidum/S. capricornutum	46.62 ± 3.59^c	44.45 ± 3.06^c	58.08 ± 4.69^a	43.36 ± 3.56^c	19.25 ± 1.27^c	18.02 ± 1.45^b	28.98 ± 2.62^ab	17.44 ± 1.35^c
CO₂ 45% (v/v)
P. geesteranus/C. vulgaris	61.92 ± 4.13^b	52.01 ± 4.39^c	54.07 ± 4.37^b	59.26 ± 4.64^b	32.45 ± 2.73^b	28.12 ± 2.63^ab	29.26 ± 2.19^b	30. 91 ± 2.68^a
G. lucidum/C. vulgaris	66.29 ± 4.27^a	59.78 ± 4.68^b	61.75 ± 4.23^a	63.07 ± 5.12^a	35.87 ± 2.98^a	30.86 ± 2.79^ab	32.81 ± 2.31^a	32.76 ± 2.84^a
P. ostreatus/C. vulgaris	60.51 ± 3.84^b	49.56 ± 4.13^cd	51.32 ± 4.15^bc	58.04 ± 4.39^b	31.13 ± 2.34^b	21.37 ± 1.75^d	27.26 ± 2.12^bc	29.91 ± 2.12^ab
G. lucidum/S. obliquus	55.76 ± 3.92^c	62.26 ± 5.02^a	63.91 ± 5.07^a	52.47 ± 4.61^c	28.37 ± 2.43^bc	32.61 ± 2.33^a	33.19 ± 2.37^a	28.39 ± 2.04^b
G. lucidum/S. capricornutum	54.26 ± 3.78^c	48.18 ± 3.96^d	49.83 ± 3.91^c	51.61 ± 4.48^c	27.18 ± 2.06^c	24.83 ± 2.02^c	25.35 ± 2.18^c	27.25 ± 2.27^b
CO₂ 55% (v/v)
P. geesteranus/C. vulgaris	63.92 ± 5.02^b	54.07 ± 4.37^b	56.29 ± 4.32^b	60.83 ± 5.34^b	33.04 ± 2.35^b	26.79 ± 2.15^b	28.14 ± 2.01^b	31.84 ± 2.63^ab
G. lucidum/C. vulgaris	68.29 ± 4.73^a	61.75 ± 4.68^a	64.21 ± 5.36^a	64.68 ± 5.61^a	37.17 ± 2.93^a	32.21 ± 2.54^a	34.05 ± 2.62^a	34.19 ± 2.71^a
P. ostreatus/C. vulgaris	62.45 ± 4.57^bc	51.32 ± 4.05^b	53.74 ± 4.41^bc	58.53 ± 4.87^bc	32.86 ± 2.56^b	26.83 ± 2.19^b	28.71 ± 2.13^b	29.34 ± 2.26^bc
G. lucidum/S. obliquus	59.17 ± 4.16^c	63.93 ± 5.13^a	61.98 ± 5.34^a	55.62 ± 4.63^cd	30.73 ± 2.88^b	33.34 ± 2.78^a	32.87 ± 2.66^a	27.63 ± 2.11^c
G. lucidum/S. capricornutum	55.72 ± 4.02^bc	59.83 ± 5.04^a	52.29 ± 4.79^c	54.84 ± 3.99^d	27.85 ± 2.29^c	31.18 ± 2.71^a	28.67 ± 2.35^b	27.59 ± 2.38^c

Note: Values with different superscript letters demonstrate a significant difference at level of p < 0.05 for the same CO₂ concentration according to the Duncan’s multiple range tests.