Digestate liquor recycle in minimal nutrients-supplemented anaerobic digestion of wheat straw

Autor: Ivo Achu Nges, Jing Liu, Zhifang Cui, Bing Wang
Rok vydání: 2015
Předmět:
Zdroj: Biochemical Engineering Journal. 94:106-114
ISSN: 1369-703X
Popis: Anaerobic digestion (AD) of minimal nutrient-supplemented wheat straw and digestate liquor recycle was evaluated in semi-continuous processes using a novel BioReactor Simulator developed for easy accurate online normalised-gas measurement. Three scenarios (i) no recycle (NR), (ii) recycle of soluble nutrient (RSN), and (iii) recycle of nutrient and microbes (RNM) were investigated in order to evaluate their respective efficiencies. Although mono-digestion of lignocellulosic biomasses are often performed with very long solid retention times (SRT), the present study demonstrated an efficient process operating with a 30-day SRT and an organic loading rate of 4 gVS/L d. The best methane yield was 303 mLCH(4)/g VS achieved in the RSN process showing a 21% improvement as compared to the NR process. The methanogenic potential of the digestates from the RSN and RNM processes was comparable to fresh inoculum indicating efficient processes. The RNM and RSN processes showed superior process stability evidenced by minimal volatile fatty acid accumulation (
Databáze: OpenAIRE