WANGYa-jun,SONG Guang-han,XUYan-chao,et al.Optimization of Carbon Emission in Membrane Bioreactor through Aeration Rate Control Integrated with Powdered Activated Carbon[J].China Water & Wastewater,2025,41(13):40-48.
Optimization of Carbon Emission in Membrane Bioreactor through Aeration Rate Control Integrated with Powdered Activated Carbon
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第13期
Page:
40-48
Column:
Date of publication:
2025-07-01
- Keywords:
- membrane bioreactor; carbon emission accounting; gas-water ratio; powdered activated carbon; greenhouse gas
- Abstract:
- This study investigated the pollutants removal and carbon reduction in a single powdered activated carbon membrane bioreactor (PAC-MBR) and its optimization measures. Six operational conditions were established by varying the gas-water ratios (50∶1, 65∶1, 80∶1) and PAC dosages (1.0 g/L and 2.0 g/L), and the accounting of CO2, N2O and CH4 emissions during the operation of the PAC-MBR process was preliminarily explored based on the mechanisms of microbial catabolism, anabolism, and endogenous metabolism, as well as the production pathways of these greenhouse gases. Under varying operating conditions, the emissions of various greenhouse gases exhibited significant differences. Specifically, the total emission of N2O reached its minimum value of approximately 0.353 9 kg (expressed in CO2 equivalents, the same below) when the gas-water ratio was set to 50∶1 and the dosage of PAC was maintained at 1.0 g/L. The minimum CO2 emissions from fossil sources were observed in the relatively aerobic zone, measuring approximately 0.012 84 kg. When the gas-water ratio was 80∶1 and the PAC dosage was 1.0 g/L, the CO2 emissions from fossil sources in the relatively anaerobic zone reached their minimum value of approximately 0.015 39 kg. The minimum CH4 emissions were observed in the relatively anaerobic zone, measuring approximately 3.347 8 kg. Regarding indirect CO2 emissions, the highest emissions occurred when the gas-water ratio was 80∶1 and the PAC dosage was 2.0 g/L. Conversely,the lowest emission was observed at gas-water ratio of 50∶1 and PAC dosage of 1.0 g/L and 2.0 g/L. From the perspective of total carbon emissions, the total carbon emission per unit volume of treated wastewater reached its minimum value at approximately 0.003 0 kg/L when the gas-water ratio was 50∶1 and the PAC dosage was 2.0 g/L. Variation in gas-water ratio has a more significant impact on overall carbon emissions compared to variation in PAC dosage.
Last Update:
2025-07-01