Pilot‐scale anaerobic thermophilic digester treating municipal sludge
Bibliographic record
Abstract
Abstract The work reported concerns anaerobic thermophilic municipal sludge digestion (55°C) in a completely mixed anaerobic digester on a pilot‐plant scale (850 L). The experimental protocol was defined to examine the effect of increasing the organic loading rate (OLR) on the efficiency of this digester and to report on its steady‐state performance. The reactor had previously been converted from mesophilic to thermophilic conditions following the protocol previously proposed by the authors: this was achieved by a modified method that combined systems investigated in Chicago and in Vancouver. The reactor was subsequently subjected to a program of steady‐state operation over a range of sludge retention times (SRTs) of 27, 20, and 15 days. The digester was fed with raw sludge [containing approximately 34.8 g/L volatile solids (VS)] three times per day. Under thermophilic conditions and with a 27‐day SRT, the reactor was operated with an OLR of 1.48 kg VS m−3 day−1. The solids removal efficiency of the reactor was 42.9%, whereas the volumetric methane production rate in the digester reached 0.35 m3 m−3 day−1. Over an operating period of 150 days, an OLR of 2.63 kg VS m−3 day−1 was achieved with 41.8% VS removal efficiency in the pilot sludge digester (SRT: 15 days). During this period the volumetric methane production rate in the digester reached 0.20 m3 m−3 day−1 and 0.20 m3/kg VSr (VS reduction). The greatest efficiency in terms of substrate removal was 54.3% for an OLR of 1.71 kg VS m−3 day−1 and SRT of 20 days. Under these conditions, the generation of biogas and methane was at levels of 0.86 and 0.58 m3 m−3 day−1, respectively, with a methane yield of 0.70 m3/kg VSr. © 2005 American Institute of Chemical Engineers AIChE J, 2006
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".