Improvement of Cu and Zn immobilization in pig manure compost by compounding acid and alkali modified biochar with bentonite clay
In order to passivate heavy metals in livestock manure and promote the resourceful and harmless utilization of agricultural waste,in this experiment,swine manure and corn cobs were used as raw materials,and a total of eight treatments were set up with the addition of acidic modified biochar 4%(F1),acidic modified biochar 4%+calcium-based bentonite 4%(F2),alkali modified biochar 4%(F3),alkali modified biochar+calcium-based bentonite 4%(F4),unmodified biochar 4%(F5),unmodified biochar+calcium-based bentonite 4%(F6),calcium-based bentonite 4%(F7)and no addition(CK)eight treatments.An aerobic composting experiment was carried out for 40 days to study the effects of acid or alkaline modified biochar and calcium bentonite on the decomposition effect of swine manure compost and the morphological transformation of heavy metals Cu and Zn.The results showed that:the pH value of the compost was 7.7-8.1 at the end of composting,which was alkaline,the EC value was less than 4 mS·cm-1,and all the composting treatments bases were physico-chemically and chemically sound.The passivation of heavy metals by F2 and F4 was better,the passivation rates of F2 on Cu and Zn were 57.98%and 40.94%respectively,and the passivation rates of F4 on Cu and Zn were 50.43%and 47.35%respectively.These results suggest that acid or alkali modified biochar and calcium bentonite have good passivation ability for Cu and Zn in the composting process,which can improve the quality of compost products.
swine manurecompostingacidor alkaline modified biocharcalcium-based bentoniteheavy metal formimmobilization
万方数据
维普
