Effect of Free Nitrous Acid on Nitrous Oxide Production and Denitrifying Phosphorus Removal by Polyphosphorus-Accumulating Organisms in Wastewater Treatment

Table 1

Batch experiment conditions applied in batch tests.

	Batch experiment 1						Batch experiment 2
	Test 1	Test 2	Test 3	Test 4	Test 5	Test 6	Test 1	Test 2	Test 3	Test 4	Test 5	Test 6
NO2-N (mg/L)	39.98	43.33	44.65	42.44	41.75	48.63	70.3	94.33	112.36	70	74.9	110.6
pH	6.0	6.5	7.0	7.5	8.0	8.5	7.5	7.5	7.5	7.0	7.0	7.0
T (°C)	24	24	24	24	24	24	19	19	19	20	20	20
FNA (mgHNO2-N/L)	92.3 × 10^−3	31.6 × 10^−3	10.3 × 10^−3	3.10 × 10^−3	0.96 × 10^−3	0.35 × 10^−3	5.87 × 10^−3	7.88 × 10^−3	9.38 × 10^−3	17.81 × 10^−3	19.06 × 10^−3	28.14 × 10^−3
Anoxic phase (min)	360	360	360	220	220	220	150	150	150	150	150	150
MLVSS (g/L)	2.478	2.752	2.506	2.746	2.744	2.456	2.206	2.44	2.156	2.348	2.194	1.77