Karrick Process Dossier (Fourth Capture): Low-Temperature Carbonization at the source archive

This page covers a fourth copy of the source dossier on the karrick-process and Low-Temperature Carbonization (LTC) (LTC). It is a variant-provenance record, not a new body of evidence. The underlying subject — Lewis Cass Karrick's low-temperature carbonization work at the US Bureau of Mines, as described in a 1932 University of Utah thesis by Larsen and Stutz — is already covered in depth by three other source articles on the same dossier, and this copy adds no substantive material beyond a distinct archive path and a different image set.

Readers looking for the mechanism, chemistry, claimed yields and the evidence assessment should start with the other source articles and the comparison page listed under Related pages below. This page exists primarily so that the provenance of this particular copy is traceable.

What this page is

The source is a source page hosted under a CoalMiningLibrary/karrick/ path on the source archive. That path differs from the locations of the three other Karrick source articles, which indicates the archive hosts multiple Karrick pages rather than one canonical document. All of these pages are therefore variants of a single dossier, not independent corroboration of one another. Two copies of the same underlying text do not constitute two sources of evidence.

The page consists of text and a logo: its only image is 0logo.gif, the archive's own logo. The page's substantive content is textual, including a gas-analysis table (Table 1) and heat-balance calculations, though several figures and drawings referred to in the text are not included in the text cited here. The logo is decorative and is not reproduced here.

Subject in brief

The Karrick process is a low-temperature carbonization variant attributed to Lewis Cass Karrick, developed during his tenure at the US Bureau of Mines. Where conventional high-temperature coking operates near 900–1100 °C, LTC heats coal at roughly 450–700 °C, driving off volatiles through Destructive Distillation and leaving a solid char. The dossier's claims concern the resulting product streams — Semi-Coke as the solid residue, Coal Tar and other condensable volatiles, and gaseous and liquid fuels — and the assertion that LTC can extract more usable fuel per ton of coal than high-temperature coking while accepting a wider range of coal grades. Those claims, and the absence of supporting test data in the dossier, are examined on Karrick Claims vs. Evidence: The Dossier's Assertions and the Absence of Test Data; they are not re-argued here.

Evidence status

The text of this page cited here may be incomplete or malformed. That is a caveat about this copy of the page, not a scientific judgment about the process. Any absence of detail in this record may reflect an incomplete copy rather than the thesis itself.

The source itself is a 1932 University of Utah civil-engineering thesis by William Larsen and Clifford Stutz, Design of Plant for Low Temperature Carbonization of Utah Coal by Karrick Process, which reports design calculations, a gas-analysis table (Table 1, from Industrial & Engineering Chemistry, vol. 19, 1927), and yield figures such as 30 gal crude oil per ton and 2200 cu ft of 950 Btu gas per ton. These are reported measurements and design estimates from a student thesis, not independent replication of the Karrick process. As with the other pages of the dossier, the material documents claims and reported figures rather than demonstrated commercial performance — the general caveat described by Patent as Evidence applies to any patent or press material reproduced in the dossier.

Structured data

The page contains no SQL DDL, schema definition, API signature or configuration block. There is nothing to preserve verbatim beyond the provenance identifiers below.

Related pages

• Karrick Process and Low-Temperature Carbonization: A source Dossier (Provisional Record) — Karrick Process and Low-Temperature Carbonization (first source article, provisional record)
• Karrick Process Dossier (Second Ingestion): Low-Temperature Carbonization at the source archive — Karrick Process Dossier (second source article)
• Karrick Process Dossier (Third Capture): Low-Temperature Carbonization at the source archive — Karrick Process Dossier (third source article)
• Karrick Claims vs. Evidence: The Dossier's Assertions and the Absence of Test Data — the claims-versus-evidence assessment shared by all pages of the dossier
• Karrick Dossier Figures: Captioned Schematics and Uncaptioned Images — the image set of the Karrick dossier
• KLTCC (Abbreviation in the Karrick Dossier Image Set) and NTU Retort (Rifle-Coal Retort Design in the Karrick Dossier) — named items appearing in the Karrick dossier image set

Open questions

1. Should multiple copies of the same dossier be merged into a single source article with a variant-provenance note, rather than proliferating near-duplicate source pages?
2. Is the CoalMiningLibrary path a distinct archive section worth a single shared provenance note across all Karrick pages?
3. Given that the text cited here may be incomplete, should the page be checked again against the archive before this record is treated as final?