Use of activated carbon to reduce ammonia emissions and accelerate humification in composting digestate from food waste

• Published in: Bioresource technology 2022-03, Vol.347, p.126701-126701, Article 126701
• Main Authors: Wang, Ning, Huang, Dandan, Shao, Mingshuai, Sun, Ran, Xu, Qiyong
• Format: Article
• Language: English
• Subjects: Activated carbon; Ammonia; Ammonia - analysis; Bacteria; Charcoal; Composting; Digestate; Food; Fungi; Manure; Nitrogen; Refuse Disposal; Soil
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.126701

[Display omitted] •AC could reduce the NH3 emission by 34% during DFW composting.•The humification process could be accelerated by the addition of AC.•The Fastidiosipila genus was developed in the fractions loosely attached to the AC.•AC could enrich the Ammoniibacillus genus to reduce nitrogen loss. Management of digestate from food waste (DFW) is becoming the bottleneck of the food waste anaerobic digestion. Composting is a feasible method to dispose the DFW and convert it to organic fertilizer; however, high ammonia (NH3) emissions and long composting time are key concerns in this process. In this study, the mechanism of activated carbon (AC) on the loss of NH3 and humification during DFW composting was investigated. The use of AC could promote humification, shorten 50% of the DFW composting period, and decrease the NH3 emissions by 34%. Results of the microbial analysis indicated that the AC could promote the growth of key microbes (i.e., Wallemia genus for fungi; and Fastidiosipila genus for bacteria). The Cladosporium and Fastidiosipila genera developed in the fractions closely and loosely attached to the AC, respectively, leading to faster degradation of lignocellulose matter. In addition, AC could enrich the Ammoniibacillus genus, reducing nitrogen loss.