TY - JOUR
T1 - Effect of C/N on composting of pig manure with sawdust
AU - Huang, G. F.
AU - WONG, Jonathan W C
AU - Wu, Q. T.
AU - Nagar, B. B.
N1 - Funding Information:
This work was financially supported by the Rockefeller Brothers Fund Ltd. The authors thank Mr. K.K Ma of Hong Kong Baptist University for his excellent technical assistance throughout the project.
PY - 2004
Y1 - 2004
N2 - The aim of this composting trial was to evaluate the effect of C/N on the composting process of pig manure with the purpose of reducing the amount of sawdust normally used as co-composting materials. Two aerobic static piles were prepared consisting of pig manure mixed with sawdust at an initial C/N of 30 (pile A) and 15 (pile B), respectively. Pile B containing larger amount of pig manure showed a slower rise in temperature, lower maximum temperature, and shorter thermophilic phase than pile A. It also resulted in higher pH and electrical conductivity (EC) values, and even higher contents of soluble NH 4-N and volatile solids throughout the composting period. Chemical and biological parameters including dissolved organic carbon (DOC) (4932 mg kg -1), soluble NH 4-N (371 mg kg -1), C/N solid (18.3), C/N aquoeus (5.8) and seed germination index (GI) (66.5%) indicated that pile A achieved maturity after 49 days of composting. After 63 days of composting, pile B contained 5352 and 912 mg kg -1 of DOC and soluble NH 4-N content, respectively, which was much higher than the criterion of 5% and 400 mg kg -1, indicating its immature nature. Pile B showed a relatively low GI value of 46%, which may be due to its high indigenous EC value as a result of larger amount of pig manure. Therefore, co-composting of pig manure with sawdust at a low initial C/N would require a composting longer than 63 days, and, the high salinity due to the large amount of pig manure would pose a potential inhibition on plant growth.
AB - The aim of this composting trial was to evaluate the effect of C/N on the composting process of pig manure with the purpose of reducing the amount of sawdust normally used as co-composting materials. Two aerobic static piles were prepared consisting of pig manure mixed with sawdust at an initial C/N of 30 (pile A) and 15 (pile B), respectively. Pile B containing larger amount of pig manure showed a slower rise in temperature, lower maximum temperature, and shorter thermophilic phase than pile A. It also resulted in higher pH and electrical conductivity (EC) values, and even higher contents of soluble NH 4-N and volatile solids throughout the composting period. Chemical and biological parameters including dissolved organic carbon (DOC) (4932 mg kg -1), soluble NH 4-N (371 mg kg -1), C/N solid (18.3), C/N aquoeus (5.8) and seed germination index (GI) (66.5%) indicated that pile A achieved maturity after 49 days of composting. After 63 days of composting, pile B contained 5352 and 912 mg kg -1 of DOC and soluble NH 4-N content, respectively, which was much higher than the criterion of 5% and 400 mg kg -1, indicating its immature nature. Pile B showed a relatively low GI value of 46%, which may be due to its high indigenous EC value as a result of larger amount of pig manure. Therefore, co-composting of pig manure with sawdust at a low initial C/N would require a composting longer than 63 days, and, the high salinity due to the large amount of pig manure would pose a potential inhibition on plant growth.
UR - http://www.scopus.com/inward/record.url?scp=4644285227&partnerID=8YFLogxK
U2 - 10.1016/j.wasman.2004.03.011
DO - 10.1016/j.wasman.2004.03.011
M3 - Journal article
C2 - 15381232
AN - SCOPUS:4644285227
SN - 0956-053X
VL - 24
SP - 805
EP - 813
JO - Waste Management
JF - Waste Management
IS - 8
ER -