ZHAO Bo-wei,NIU Yu-kun,XIE Fei,et al.Pilot-scale Study on Resource Recycling of Excess Sludge Carbonized Pyrolysis Liquid[J].China Water & Wastewater,2021,37(19 19):1-6.
Pilot-scale Study on Resource Recycling of Excess Sludge Carbonized Pyrolysis Liquid
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
19 19
Page:
1-6
Column:
Date of publication:
2021-10-01
- Keywords:
- excess sludge; carbonized pyrolysis liquid; resource recycling; carbon resource for denitrification; biogas
- Abstract:
- The first large-scale sludge carbonization project in China has been established in a wastewater treatment plant in Jinzhong, Shanxi Province. The project has a treatment capacity of 300 t/d and a good treatment performance. However, the concentrations of COD and ammonia nitrogen in the carbonized pyrolysis liquid are as high as 20 000 mg/L and 1 200 mg/L, and the liquid also contains a lot of refractory organic matters, leading to its treatment becomes the main reason restricting the development of this process. Therefore, two resource utilization schemes were proposed, namely preparation of denitrifying carbon source and methane production from the carbonized pyrolysis liquid, and a pilot plant with a treatment capacity of 1 m3/d was constructed. The methane production rate of the organic compounds in the pyrolysis liquid reached 0.33 m3/kgCOD through the anaerobic methanogenic process, which proved that this liquid had a good methanogenic potential. The COD acidification rate, COD loss rate and ammonia nitrogen removal efficiency in the carbonized pyrolysis liquid reached more than 50%, 14.2% and 85% by the anaerobic acidification combined with ammonia stripping process. The denitrifying performance of the carbon source prepared by the pyrolysis liquid was slightly worse than that of the sodium acetate but better than that of the glucose, indicating that it was a good denitrifying carbon source. According to the results of the pilot test and the price in the market, the sludge carbonization project that produced 300 m3/d pyrolysis liquid could save energy cost of 1.419 9 million yuan per year if methane was recovered, and carbon source consumption cost of 4.675 7 million yuan per year if carbon source was recovered.
Last Update:
2021-10-01