Effect of salinity stress on nitrogen and sulfur removal performance of short-cut sulfur autotrophic denitrification and anammox coupling system

The effects of salinity on anaerobic nitrogen and sulfide removal were investigated in a coupled anammox and short-cut sulfur autotrophic denitrification (SSADN) system. The results revealed that salinity had significant nonlinear ef-fects on the nitrogen and sulfur transformations in the coupled system. When the salinity was <2 %, the anammox and SSADN activities increased with increasing salinity, and the total nitrogen removal rate, S0 production rate, and nitrite production rate were 0.41 kg/(m3 center dot d), 0.37 kg/(m3 center dot d), and 0.28 kg/(m3 center dot d), respectively. With continuous in-crease of salinity, the performances of the anammox and SSADN gradually decreased, and the three indicators

Automated summary

This study investigated the effects of salinity on anaerobic nitrogen and sulfide removal in a coupled anammox and short-cut sulfur autotrophic denitrification (SSADN) system. The results showed that salinity had significant nonlinear effects on nitrogen and sulfur transformations in the system. At salinity levels below 2%, anammox and SSADN activities increased with increasing salinity, while at higher salinity levels, the performances of the two processes gradually decreased.