Dataset Information

Synergistic Effects on the Co-pyrolysis of Agricultural Wastes and Sewage Sludge at Various Ratios.

ABSTRACT: This study investigated the co-pyrolysis of blends of sewage sludge (SS) with rice husk (RH) and with hemp straw (HS) at different ratios by using thermogravimetry (TG) and its rate (DTG, derivative TG) analysis at heating rates of 10, 20, and 30 K/min. The resulting kinetic parameters of activation energy (E _a) were calculated by both Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose models, followed by comparison of experimental values with calculated values to reveal the synergistic effects of SS/RH and SS/HS. With increasing additions of RH or HS to SS, a gradual decreasing trend in the experimental pyrolysis temperature range was evident, ranging from 144.5 to 95.2 °C for SS/RH and from 144.5 to 88.8 °C for SS/RH. Moreover, such temperature ranges were 6.7-20.4 °C less than the calculated values at the same blending ratio. The fitting results of the two kinetic models showed that with the same SS mass ratio, the experimental E _a ^* (average activation energy) of both SS/RH and SS/HS were less than the calculated E _a ^*. Especially, the experimental E _a ^* of 7SS-3RH was lower around 43.8% than the calculated E _a ^*, whereas the experimental E _a ^* of 3SS-7HS was lower by about 39.4% than the calculated E _a ^*. Synergistic analysis demonstrated that the co-pyrolysis of RH or HS with SS at various mass ratios presented obvious synergistic effects and then the decrease of E _a. The mechanism experiment showed that the co-pyrolysis of SS/HS may promote the decrease of E _a by changing the co-pyrolysis gas products or by increasing the overflow of volatile matter and then forming intermediate transition products, while SS/RH may accelerate the decrease of the E _a by using an appropriate K addition ratio from RH as a metal catalyst.

SUBMITTER: Chen X

PROVIDER: S-EPMC8757449 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Anaerobic co-digestion (Co-AD) is used to increase the effectiveness of anaerobic digestion (AD) using local "wastes", adding economic and environmental benefits. Since system stability is of existential importance for the operation of wastewater treatment plants, thorough testing of potential co-substrates and their effects on the respective community and system performance is crucial for understanding and utilizing Co-AD to its best capacity. Food waste (FW) and canola lecithin (CL) were tested in mesophilic, lab-scale, semi-continuous reactors over a duration of 120 days with stepwise increased substrate addition. Key performance indicators (biogas, total/volatile solids, fatty acids) were monitored and combined with 16S-rRNA amplicon sequencing to assess the impact of co-substrate addition on reactor performance and microbial community composition (MCC). Additionally, the latter was then compared with natural shifts occurring in the wastewater treatment plant (WWTP, source) at the same time. An almost linear increase in biogas production with both co-substrates at an approximate 1:1 ratio with the organic loading rate (OLR) was observed. The MCCs in both experiments were mostly stable, but also prone to drift over time. The FW experiment MCC more closely resembled the original WWTP community and the observed shifts indicated high levels of functional redundancy. Exclusive to the CL co-substrate, a clear selection for a few operational taxonomic units (OTUs) was observed. There was little evidence for a persistent invasion and establishment of microorganisms from typical primary substrates into the stable resident community of the reactors, which is in line with earlier findings that suggested that the inoculum and history mostly define the MCC. However, external factors may still tip the scales in favor of a few r-strategists (e.g., Prolixibacter) in an environment that otherwise favors K-strategists, which may in fact also be recruited from the primary substrate (Trichococcus). In our study, specialization and diversity loss were also observed in response to the addition of the highly specialized CL, which in turn, may have adverse effects on the system's stability and reduced resilience and recovery.

Dataset Information

Synergistic Effects on the Co-pyrolysis of Agricultural Wastes and Sewage Sludge at Various Ratios.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets