HAO Xiao-di,ZHANG Yi-ning,LI Ji,et al.Case Analysis of Energy Neutrality and Carbon Neutrality for Wastewater Treatment[J].China Water & Wastewater,2021,37(20 20):1-8.
Case Analysis of Energy Neutrality and Carbon Neutrality for Wastewater Treatment
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
20 20
Page:
1-8
Column:
Date of publication:
2021-10-17
- Keywords:
- wastewater treatment; energy neutrality; carbon neutrality; greenhouse gases (GHGs); anaerobic digestion; thermal energy
- Abstract:
- Due to the high energy consumption and direct greenhouse gases (GHGs) emission, carbonneural operation of wastewater treatment process has become imperative. However, energy neutrality of wastewater treatment plants (WWTPs) is often pursued, which is easily confused with the concept of carbon neutrality. With this study, three different European WWTPs are utilized to elucidate the difference between energy neutrality and carbon neutrality. The case studies indicate that achieving energy neutrality does not mean that carbon neutrality can be realized at the same time. Reversely, energy neutrality should be simultaneously realized if carbon neutrality is achieved. This is because there are also direct GHGs like NxO, CH4, and VOCs during the treatment process (biogenic CO2 converted from COD is not included in the carbon emission inventory), besides indirect carbon emissions from energy consumption. Furthermore, both production and transportation of chemicals (such as carbon sources, chemical phosphorus agents, etc.) can indirectly generate GHGs. Afforestation, wind power, and anaerobic co-digestion with exogenous organics can certainly contribute to carbon neutrality for WWTPs, but these measures are usually conducted outside WWTPs so that they should be called as “pseudo-neutrality”. In fact, simultaneously achieving energy neutrality and carbon neutrality for WWTPs can be only accomplished under the condition of utilizing thermal energy.
Last Update:
2021-10-17