The Effect of Biochar and Pyroligneous on the Composting Process of Phosphorus Tailings and Activating Phosphorus

PurposeTo explore the effects of biochar and pyroligneous on the process of composting and phosphorus activation of scrub tailings.

MethodsBio-phosphorus fertilizer was prepared by exogenous addition of biochar, pyroligneous and compost material (sawdust+wheat bran) in different proportions.

ResultsThe addition of biochar and pyroligneous mixed that could increase the temperature of the heap quickly, effectively shorten the compost fermentation time, and promote the composting process. The activation rate of phosphorous tailings treated with biochar+pyroligneous (TC) increased by 3.16%, 4.62%, and 9.99% compared with biochar treatment (T), pyroligneous treatment (C) and blank control (CK), respectively. Except for pyroligneous treatment (C), the total amount of organic acids in biochar+pyroligneous treatment (TC) increased significantly (P<0.05). The contents of tartaric acid, malic acid and citric acid of TC trentment in the high temperature stage increased exponentially compared with other treatments; and the activation rate of phosphorus increased with the increase of acetic acid content in the high temperature stage. Correlation analysis of various factors of composting showed that there was a significant positive correlation between the available phosphorus content and the total organic acid in the high temperature stage of compost (P<0.01).

ConclusionThe mixed addition of biochar and pyroligneous is better than single use, which promotes the production of organic acids and improves the activation of phosphorus in phosphorus tailings compost.