Search

An NH

Although the composting-biotrickling filter coupled system removed ammonia-based odor pollution, other pollutants (nitrogen-rich wastewater) arose. This study intended to determine the effect of in-situ disposal of different kinds of nitrogen-rich wastewater [i.e., multi-nitrogen (NH

Effect of diverse Lactobacillus amylophilus, Geobacillus thermoleovorans, and Bacillus subtilis inoculation patterns on the co-composting performance of food waste and biogas residue was explored. Experimental results revealed that, compared to the single-stage inoculation and non-inoculation groups, the multistage inoculation pattern prolonged the thermophilic period during composting, consequently improving organic matter decomposition and humification [with a high germination index (120.9%)]. In addition, it could promote the development of humic substances [with a high humus index (4.3) and biological index (1.4)] and lower emissions of carbon dioxide (CO

Biogas residue (BR) is difficult to transport and compost due to its high moisture content. The purpose of this study was to elucidate the dewatering and microbial mechanisms underlying the inoculation of a thermophilic bacterial agent (TBA) onto BR with a high moisture content (i.e., 90.4%). TBA accounted for 78.7% of the water loss rate in BR, dramatically higher than the effects of aeration, external heat, or indigenous microorganisms (i.e., 1.8%, 0.1%, and 19.4%, respectively). Furthermore, TBA inoculation resulted in a stable product [with a low moisture content (9.4%) and a high seed germination index (107.3%)]. Finally, TBA increased microbial diversity and the abundance of functional bacteria (Proteobacteria and Bacteroidota), which might be beneficial for refractory organic compound decomposition and plant growth. Thus, biodrying BR via inoculation with a TBA is recommended economically.

A weakly acidic ammonium-rich wastewater (STL) was intended to reuse as a moisture conditioning agent for composting to increase nitrogen content of compost. The influence of adding STL in the mesophilic period (MP), thermophilic period (TP), and cooling period (CP) on composting performance was investigated. Results revealed that organic degradation was strongly suppressed in MP, whereas no difference (p 0.05) was observed between CP and control group (using tap water as moisture conditioning agent). The hydrolysis and mineralization of organic matter in TP were partly stimulated because reusing STL reduced free ammonia concentrations (400 mg/L) of windrows. Additionally, the ammonium and nitrate nitrogen content of compost in TP increased by 71% and 425% without additional greenhouse gas emissions compared with control group. Therefore, ammonium-rich wastewater like STL could substitute tap water to condition compost moisture content and increase the nitrogen content of compost during the thermophilic composting period.