Effect of biochar amendment on compost quality, gaseous emissions and pathogen reduction during in-vessel composting of chicken manure.

Because of rapid development in the livestock industry, the production of chicken manure has subsequently increased, which may contribute to environmental pollution. In this regard, in-vessel composting of biochar amended chicken manure and sawdust mixtures was investigated to find out the effect of biochar at the ratios of 0% (control), 3% (T1), 5% (T2), and 10% (T3) on ammonia and greenhouse gases (GHGs) emission, compost quality, pathogenic contaminants and phytotoxicity. The composting process was performed in 100-L, pilot-scale, plastic, cylindrical vessels for 50 days. The addition of biochar (3%, 5%, and 10%) increased the thermophilic temperature with a significant reduction in gaseous emissions (ammonia and CO2), microbial pathogens (Escherichia coli and Salmonella sp.), and phytotoxicity (Lepidium sativum seed germination assay) compared with that of the control compost products. However, according to the obtained results with in-vessel composting, the amendment of 10% biochar showed the most significant effects concerning the quality of the compost nutrients. The study reveals that the addition of biochar during in-vessel chicken manure composting is beneficial in the reduction of gaseous emissions and pathogenic microorganisms apart from improvement in plant nutrients.

Chung WJ ，Chang SW ，Chaudhary DK ，Shin J ，Kim H ，Karmegam N ，Govarthanan M ，Chandrasekaran M ，Ravindran B ... -  《-》

Influence of biochar on physico-chemical and microbial community during swine manure composting process.

Excessive nutrients and toxic gas emissions from animal manure management are of great global concern, with negative environmental and economic consequences worldwide. Due to biochar recalcitrance and sorption properties, this study investigated the effect of the biochar(BC) derived from bamboo, amendment on swine manure(SM) composting efficiency through physical, physio-chemical, gaseous emissions, microbiological, and phytotoxic analysis during the 56 day process of in-vessel composting. The treatments were set-up from different ratios of biochar to swine manure mixed with sawdust(SD)(i.e. SM + SD + 3%BC(T1), SM:SD + 5 %BC(T2) and SM:SD + 10 %BC (T3)), while treatment without biochar amendment was used as a control, SM:SD(C). The results showed that, compared to the control, biochar amended compost mixtures had significantly reduced (p ≤ 0.05) bulk density, organic matter(OM), C:N ratio, NH3 emission, pathogenic microorganisms, and phytotoxicity effect (Cress seed, Lepidium sativum Linn.). On the other hand, biochar amendment mixtures had increased total porosity, water holding capacity, rapid thermophilic temperature, and nitrate nitrogen. However, with the most prominent effects in terms of the nutrient quality and degradation rate of compost mixtures, the amendment of 10% biochar is recommended for swine manure management through the composting process.

Ravindran B ，Nguyen DD ，Chaudhary DK ，Chang SW ，Kim J ，Lee SR ，Shin J ，Jeon BH ，Chung S ，Lee J ... -  《-》

Feedstock optimization with rice husk chicken manure and mature compost during chicken manure composting: Quality and gaseous emissions.

This study investigated the impact of mature compost input on compost quality, greenhouse gases (GHGs, i.e. methane and nitrous oxide) and ammonia emissions during chicken manure and rice husk chicken manure co-composting. The experiment used different volumes of mature compost: 10% (T1), 20% (T2), and 30% (T3) to replace rice husk chicken manure. Results showed that mature compost enhanced compost maturity by promoting the activities of Bacillus, Caldicoprobacter, Thermobifida, Pseudogracilibacillus, Brachybacterium, and Sinibacillus. Compared to CK, T1, T2, and T3 reduced NH3 emission by 32.07%, 33.64%, and 56.12%, and mitigated 14.97%, 16.57%, and 26.18% of total nitrogen loss, respectively. Additionally, T2 and T3 reduced CH4 emission by 40.98% and 62.24%, respectively. The N2O emissions were positive correlation with Lactobacillus, Pseudogracilibacillus and ammonium nitrogen (p < 0.05), while T2 reducing total greenhouse effects. Therefore, replacing rice husk chicken manure with 20% mature compost is an efficient and promising approach for composting.

Li M ，Li S ，Meng Q ，Chen S ，Wang J ，Guo X ，Ding F ，Shi L ... -  《-》

Co-composting of food waste and swine manure augmenting biochar and salts: Nutrient dynamics, gaseous emissions and microbial activity.

The prominent characteristics of the biochar, high porosity, sorption capacity with low density improve the aeration, making it a desirable amendment material for composting process. The composting efficiency was analysed by the impact of rice husk biochar amendment (0, 2, 4, 6, 8 and 10%) in the presence of salts for the co-composting of food waste and swine manure, in composting reactors for 50 days. Results revealed that biochar amendment had improved the degradation rates by microbial activities in comparison with control. The final compost quality was improved by reducing the bulk density (29-53%), C/N ratio (29-57%), gaseous emissions (CO2, CH4, and NH3) and microbial pathogens (Escherichia coli and Salmonella sp.). However, 6% biochar amendment had significant improvement in compost quality, degradation rates and nutritional value which is recommended as the ideal ratio for obtaining mature compost from the feedstock, food waste and swine manure.

Ravindran B ，Awasthi MK ，Karmegam N ，Chang SW ，Chaudhary DK ，Selvam A ，Nguyen DD ，Rahman Milon A ，Munuswamy-Ramanujam G ... -  《-》

Effects of microbial culture and chicken manure biochar on compost maturity and greenhouse gas emissions during chicken manure composting.

The effects of chicken manure biochar (CMB) and chicken manure integrated microbial consortium (CMMC) as co-amendments were assessed on compost maturity and reduction of greenhouse gases and ammonia (NH3) emissions during chicken manure composting. Composting was conducted using six combinations of CMB and CMCC (0 % CMB + 0 % CMMC, 0 % CMB + 10 % CMMC, 2 % CMB + 10 % CMMC, 4 % CMB + 10 % CMMC, 6 % CMB + 10 % CMMC, 10 % CMB + 10 % CMMC added on a dry weight basis) in six polyvinyl chloride composting reactors for 42 days under an aerobic environment. Co-amendment of CMB and CMMC extended the thermophilic stage and promoted compost maturity. The release of greenhouse gases [nitrous oxide (N2O) and methane (CH4)] and NH3 from treatments co-amended by CMB and CMMC were reduced by 19.0-27.4 %, 9.3-55.9 % and 24.2-56.9 %, respectively, compared with the control. In addition, a redundancy analysis showed that the C/N ratio and temperature had a significant relationship with greenhouse gases and NH3 emissions among all physiochemical characteristics.

Chen H ，Awasthi SK ，Liu T ，Duan Y ，Ren X ，Zhang Z ，Pandey A ，Awasthi MK ... -  《-》