Karrick Process Dossier (Second Ingestion): Low-Temperature Carbonization at the source archive

This page records a second source file covering the same subject matter as the earlier Karrick dossier: the low-temperature carbonization (LTC) of coal associated with Lewis Cass Karrick and the US Bureau of Mines. The file is a compilation of article text, patent references and three images (karrick1.gif, karrick2.gif, karrick3.gif) hosted under the source archive Karrick directory. Its content overlaps almost entirely with the previously ingested dossier at [source note 3]; the file hash differs, but the source URL, folder context and image set match.

Because the underlying material is the same, this page is written as a provenance record and cross-check rather than a fresh technical account. The substantive explanation of the process lives on karrick-process and Low-Temperature Carbonization (LTC); the claim-versus-evidence analysis lives on Karrick Claims vs. Evidence: The Dossier's Assertions and the Absence of Test Data.

What the dossier contains

The dossier is a text-and-image compilation in the source archive house style: a short framing essay, quoted or paraphrased descriptions of the process, references to patents and Bureau of Mines publications, and three illustrative figures. It is not an experimental report. It contains no laboratory protocol and no independent test data; the yield figures it gives (for example up to a barrel of oil, 3000 cu ft of fuel gas and 1500 lb of char per ton of coal) are quoted claims without stated uncertainty.

The three images are the same set used in the earlier Karrick ingestion:

• karrick1.gif — image file referenced at the end of the source.
• karrick2.gif — image file referenced at the end of the source.
• karrick3.gif — image file referenced at the end of the source.

The source supplies no captions or descriptive text for these images.

The process as the dossier describes it

The dossier restates the standard description of LTC: coal is heated in the absence of air at a temperature well below that used in conventional high-temperature coking, driving off volatile matter and leaving a solid char. The dossier quotes about 800 °F (roughly 430 °C) for the Karrick LTC step, in the absence of oxygen; the general literature places LTC well below the temperatures used in conventional high-temperature coking. The three product streams are:

1. Semi-Coke — the solid residue, described as a smokeless fuel.
2. Coal Tar — the condensable liquid fraction, a source of chemicals and liquid fuel precursors.
3. Gas — a combustible off-gas.

This is the same description given in the earlier dossier and in the general literature on Destructive Distillation. The dossier frames the Karrick variant as producing more useful liquid product per ton of coal than high-temperature carbonization, and links it to the broader idea of Coal Liquefaction.

Claims carried by the dossier

The dossier's assertions, as previously captured in the wiki, are:

• LTC yields more liquid fuel per ton of coal than high-temperature carbonization.
• The process yields a smokeless solid fuel plus tar and gas.
• The technology was allegedly suppressed or underfunded in favour of petroleum-based routes.

The third item is an assertion about institutional behaviour, not a demonstrated finding. The dossier supplies no documentary evidence of suppression — no memoranda, budget records or correspondence — and no energy balance or third-party replication that would establish the first two claims. This gap is the subject of Karrick Claims vs. Evidence: The Dossier's Assertions and the Absence of Test Data.

Evidence status

The dossier is therefore best read as a pointer to primary sources — patents and Bureau of Mines publications — rather than as evidence in its own right. A patent or an archive listing is not proof of effectiveness; see Patent as Evidence.

Relationship to the earlier ingestion

This file is a near-duplicate of the Karrick dossier already represented by [source note 3]. The two files share:

• the same subject (Karrick and LTC),
• the same source directory and page ([source note 4]),
• the same three images.

They differ in file hash. No new technical detail, patent number, temperature table or yield figure was identified in this file that is absent from the earlier coverage. The correct treatment is to keep this page as a provenance record and to route readers to the existing cluster rather than to fork a parallel technical account.

Related work

• karrick-process — the named process.
• Low-Temperature Carbonization (LTC) — the general technique.
• Semi-Coke, Coal Tar, Destructive Distillation, Coal Liquefaction — the products and adjacent concepts.
• Lewis Cass Karrick, US Bureau of Mines — the inventor and his institutional home.
• Karrick Claims vs. Evidence: The Dossier's Assertions and the Absence of Test Data — the claim-versus-evidence analysis.
• the source archive — the archive that compiled the dossier.