Carbon and nitrogen removal through “Candidatus Brocadia sinica”-dominated simultaneous anammox and denitrification (SAD) process treating saline wastewater

•Simultaneous C and N removal was achieved by SAD process under saline condition.•“Candidatus Brocadia sinica” had good tolerance to salinity in SAD process.•Percentage of nitrogen removal by anammox was higher than that by denitrification.•Modified Boltzmann model could analyze the effect resulting from salinity.