Advanced Search
Immobilization of heavy metals by modified biochar during composting of pig manure
Received:December 19, 2017  
View Full Text  View/Add Comment  Download reader
KeyWord:composting;modified biochar;heavy metal;immobilization
Author NameAffiliationE-mail
LI Ran College of Resources and Environment Science, Agricultural University of Hebei, Baoding 071001, China
Institute of Energy and Environmental Protection, Chinese Academy of Agricultural Engineering, Beijing 100125, China
Key Laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture, Beijing 100125, China 
 
MENG Hai-bo Institute of Energy and Environmental Protection, Chinese Academy of Agricultural Engineering, Beijing 100125, China
Key Laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture, Beijing 100125, China 
 
SHEN Yu-jun Institute of Energy and Environmental Protection, Chinese Academy of Agricultural Engineering, Beijing 100125, China
Key Laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture, Beijing 100125, China 
 
ZHOU Hai-bin Institute of Energy and Environmental Protection, Chinese Academy of Agricultural Engineering, Beijing 100125, China
Key Laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture, Beijing 100125, China 
 
ZHANG Xi Institute of Energy and Environmental Protection, Chinese Academy of Agricultural Engineering, Beijing 100125, China
Key Laboratory of Technologies and Models for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture, Beijing 100125, China 
 
WEN Hong-da College of Resources and Environment Science, Agricultural University of Hebei, Baoding 071001, China 2804529324@qq.com 
Hits: 2409
Download times: 2146
Abstract:
      Residual heavy metals in pig manure compost are a potential risk to soil and food security. Three kinds of biochar:unmodified biochar, NaOH-modified biochar, and FeCl3-modified biochar were added during pig manure composting to illustrate their heavy metals immobilization effect. The temperature, pH values, and EC values of the compost were determined. The distribution of different phases of Cu, Zn, and Pb was detected by modified BCR sequential extraction method, and their immobilization rate was determined. The results showed that all four treatments met the requirements of harmless treatment when the temperature was maintained above 55℃ for over 5 d, and the seed germination index reached 80%~85%. The pH values of the four composts were 8.0~9.0. The EC value of composts treated with FeCl3-modified biochar was 3.53 mS·cm-1, while the EC values was just above 4.0 mS·cm-1 in the compost treated with unmodified biochar and NaOH-modified biochar. The immobilization rate of heavy metals was significantly higher in biochar treated compost than in the control. Furthermore, the immobilization rate of Cu, Zn, and Pb (78.70%, 43.53%, and 66.45%, respectively) was the highest in the compost treated with FeCl3-modified biochar among the three kinds of biochar. These results suggest that modified biochar can improve immobilization in pig compost, and indicate its potential to alleviate the risk of heavy metals contamination of pig manure treatment and disposal.