HAOXiao-di,LIJia-yong,HAOLi-ting,et al.Analysis and Assessment on the Feasibility of Sludge-based Biochar[J].China Water & Wastewater,2023,39(20):1-8.
Analysis and Assessment on the Feasibility of Sludge-based Biochar
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第20期
Page:
1-8
Column:
Date of publication:
2023-10-17
- Keywords:
- waste activated sludge; straw; biochar; heavy metals
- Abstract:
- With the background of carbon neutrality, resource and energy utilizations of waste activated sludge (WAS) have become a future topic of research and application. Biochar produced by WAS seems currently attractive in the aspect of research & development (R & D). However, is it practical for sludge conversion to biochar-Based on a summarized description on the principles and processes of biochar production, this article is dealt with quantitative (calculation-based) evaluations on energy consumption, cost and performance of sludge-based biochar, which is then compared with those of straw-based biochar. The calculated results reveal that sludge-based biochar would consume a lot of net energy (-695 kW·h/tDS), which can not balance the energy input and thus result in a high producing cost, up to 927.49 yuan per ton of biochar. By comparison, the manufacturing process of straw-based biochar could produce an energy surplus of 1 400 kW·h/t straw, associated with a lower producing cost, down to 575.72 yuan per ton of biochar. Regarding the carbon-fixation performances, the fixed carbon content by sludge-based biochar is about 20% of straw-based biochar, while sludge-based biochar contains two-time higher ash content than that of straw-based biochar. Clearly, sludge-based biochar has no priority over straw-based biochar, in regard of both production and performance. Considering straw-based biochar has not been applied widely, input into R & D on sludge-based biochar is inappropriate.
Last Update:
2023-10-17