Table 8.

Performance of autotrophic denitrification systems.

	Electron donor	Influent N concentrations (mg-N/L)	NRE (%)	NRR (kg-N/m3-day)	Remarks	References
1	S2−	20	25–98	-	NO3−—fed; N/S = 0.9&1.7	Moraes et al. (2012)
2		20	95–100	0.009	NO2−—fed; N/S = 1.5&2.8
3	S2O32−	56	-	0.47	415 mgSO42−produced	Cardoso et al. (2006)
4	S2−		-	0.10	87 mgSO42−produced
5	S		-	0.050	16 mgSO42−produced
6	S	30–60	30–100b	0.30	Sulphur/limestone (v/v) = 1–3	Sahinkaya et al. (2014)
7		25 ± 3	100	0.15	Sulphur/limestone (v/v) = 1
8	H2	20–40	92–96	2.7–5.3c	Microporous membrane bioreactor	Mansell and Schroeder (2002)
9	S	29–31	79–98	0.05–0.36	10 L sulfoxidizing MBBR	Cui et al. (2019)
10	FeS2	27	57	0.080d	25–50 μm and 50–100 μm pyrite particles	Torrentó et al. (2010)
11	S2O32−	60–80	-	0.058e	S2O32−-driven denitritation	Qian et al. (2016)
12	H2	25–400	97	1.9–5.8	16.8 l pressurized reactor	Keisar et al. (2021)

^aApproximated from Figure 4a in the source file.

^bEstimated from Figure 4 in the source file.

^cg-NO₃⁻-N/m²-day.

^dg-NO₃⁻-N/kg-pyrite-day.

^eEstimated from Figure 3c in the source file.