HAOXiao-di,SHENZhan,LIJi,et al.Low?temperature Sludge Drying: Priority to Thermal Energy in Effluent[J].China Water & Wastewater,2023,39(6):1-8.
Low?temperature Sludge Drying: Priority to Thermal Energy in Effluent
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第6期
Page:
1-8
Column:
Date of publication:
2023-03-17
- Keywords:
- excess sludge; moisture content; low-temperature drying; sludge incineration; thermal energy; water source heat pump
- Abstract:
- Sludge drying and incineration have been identified as an ultimate approach to treating and disposing excess sludge from wastewater treatment, which is also a technical trend in practice. However, choosing heat sources is a decisive factor on energy consumption and associated carbon emissions. Except for economically available high-temperature source, high-temperature sludge drying is unsustainable. Under the circumstance, low-temperature sludge drying has been become a research topic recently, especially with cleaner energy. In fact, renewable heat sources, such as solar energy, microwave energy, air-source heat, geothermal heat, and wastewater source heat, are gaining more and more attentions to. Among them, thermal energy extracted from effluent in wastewater treatment plants (WWTPs) is a kind of low-grade heat, which has been easily available but neglected chronically. The previous calculated results reveal that heat exchanged from effluent with 4 ℃ could offer 3 times higher thermal energy (about 60 ℃ hot water) needed of sludge drying, which could not only meet the need of drying energy but also achieve carbon-neutral operations of WWTPs. Thus, decentralized low-temperature sludge drying with thermal energy and centralized sludge incineration for combined heat and power (CHP) would become a developing goal for sludge treatment and disposal.
Last Update:
2023-03-17