80 / 2021-06-30 17:30:34

添加剂对鸡粪堆肥腐熟度和气体排放的影响/The effect of additives on gas emissions and antibiotic degradations during chicken manure composting

biochar； superphosphate; magnesium sulfate; gas emissions;antibioctic degradations; chicken manure comosting

    The issue of pollutant gas emissions during composting and antibiotic residues in compost product has greatly attracted the attention of researchers. Adding additives to pile could adjust the production of pollutant gases and the degradation of antibiotics so as to decreasing the environmental pollution and improving the compost quality. During the 35-day composting, the chicken manure was mixed with corn stalks as raw material, and then added no material (CK), biochar (BC), superphosphate (SP), superphosphate+magnesium sulfate (SP+MS), biochar+superphosphate+magnesium sulfate (BC+SP+MS) to five piles，respectively. According to the temperature (T), pH and germination index (GI), all five treatments met the maturity standards. In terms of the gas emissions, the combined addition of superphosphate and magnesium sulfate significantly reduced ammonia (NH₃) emissions, and the reduction rate were 47.9% (SP+MS) and 38.7% (BC+SP+MS), respectively. However, adding the biochar would promote the NH₃ emission, specifically, the NH₃ emission in BC treatment was 16.2% higher than that in CK treatment and the BC+SP+MS treatment was 17.7% higher than SP+MS treatment. In addition, the additives all increased the N₂O emission (118.9%-210.0%) and the smallest promotion effect occurred in the treatments of SP+MS and BC+SP+MS. The major sulfur-contained odors were hydrogen sulfide (H₂S), dimethyl sulfide (Me₂S), and dimethyl disulfide (Me₂S₂). The combined addition of biochar, superphosphate, and magnesium sulfate (BC+SP+MS) had the highest reduction rate to H₂S (35.30%) and Me₂S₂ (96.99%), and the second reduction rate of Me₂S (79.44%) also occurred in BC+SP+MS treatment. From the perspective of the total amount of sulfur-contained odors, there was the highest reduction rate (72.02%) in the BC+SP+MS treatments. About the antibiotics, most degraded during the first 14 days and the degradation rate of tetracycline, quinolone and sulfa were 82.8%, 92.05%, 82.21%, respectively. The sulfa antibiotics (Sulfametoxydiazine and Sulfachlorpyridazine) were enriched at the end of composting. Different additives had little effect on the antibiotic degradation and adding the biochar reached the highest reduction rate (95.25%). In summary, the combined addition of biochar, superphosphate, and magnesium sulfate is most conducive to the reduction of NH₃、N₂O and sulfur-contained odors and additives have no significant effect on the antibiotic degradation.