WANG Xiang,CHEN Tao,KONG De-fang,et al.Effect of Temperature on Denitrification of Sulfur Autotrophic Horizontal Subsurface Flow Constructed Wetland[J].China Water & Wastewater,2020,36(23 23):75-80.
Effect of Temperature on Denitrification of Sulfur Autotrophic Horizontal Subsurface Flow Constructed Wetland
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
23 23
Page:
75-80
Column:
Date of publication:
2020-12-01
- Keywords:
- horizontal subsurface flow constructed wetland; sulfur autotrophic denitrification; wetland matrix combination; denitrification effect; microbial community
- Abstract:
- Denitrification is the main way of nitrogen removal in wetlands. A typical characteristic of low C/N ratio of wastewater treatment plant tail water restricts the effect of heterotrophic denitrification. However, the application of sulfur autotrophic denitrification technology to constructed wetlands can effectively solve the bottleneck of poor nitrogen removal efficiency in horizontal subsurface flow wetlands. Appropriate functional matrix for subsurface flow wetland denitrification was selected to treat tail water from a wastewater treatment plant, and the optimal denitrification performance was eventually obtained when the volume ratio of reduced sulfur, zeolite and gravel was 1 ∶1 ∶1. The addition of reduced sulfur could significantly improve the denitrification efficiency of the subsurface flow wetland. The temperature had great influence on denitrification efficiency of sulfur autotrophic subsurface flow wetlands. When temperatures were 25-30 ℃ and 17-19 ℃, nitrogen removal rate was above 90%, and about 80% at temperature of 11-13 ℃. However, the nitrogen removal efficiency of the wetlands with sulfur, limestone and gravel as matrix decreased to 47% at temperature of 6-8 ℃. Thirty-seven genera were discovered in sulfur autotrophic subsurface flow wetlands. The dominant sulfur autotrophic bacteria included Thiobacillus, Sulfurimonas and so on, and the number of sulfur autotrophic denitrifying bacteria was positively correlated with the denitrifying rate of the system.
Last Update:
2020-12-01