Performance and microbial structure of partial denitrification in response to salt stress: Achieving stable nitrite accumulation with municipal wastewater

•PD could treat saline nitrate sewage by using carbons in municipal wastewater.•High NTR of ~ 80% was achieved with salinity of 1.25 wt% and CODini/NO3-ini of 3.7.•Thauera was remained predominant but with abundance decreased to 42.36% (1.25 wt%).•Suitable NO2-eff/NH4+eff (~1.6) provided a possibility for combing PD with anammox.