Document Parsing and Chunking for Coal Chemical Industry Research Report Retrieval

What the data for this category looks like

The data for coal chemical industry research reports mainly comes from national coal industry associations, public announcements of coal chemical enterprises, and special survey content from third-party industry consulting institutions. Update cycles are dominated by monthly supply and demand reports, quarterly capacity statistics, and annual industrial plans. Temporary research reports are also released alongside coal price fluctuations and policy adjustments. Document structures typically include tables of contents, structured supply and demand tables, process flow diagrams, price trend charts, embedded Excel-format capacity distribution details, and PDF-format policy attachments. Professional fields include coal consumption per ton, capacity in ten thousand tons/year, sales price in yuan/ton. Some documents include segmented data tables with unit labels.

Constraints on document parsing and chunking

The structured tables, embedded images, and professional unit fields in coal chemical industry research reports impose multiple constraints on the parsing and chunking process. First, a large number of embedded process flow diagrams and price trend charts cannot fully convey information through plain text parsing alone. Image resources must be extracted simultaneously and associated with their surrounding context. Second, professional fields are tightly bound to their units. Forced paragraph splitting during chunking will prevent large models from identifying the specific capacity subject corresponding to "ten thousand tons/year". In addition, long documents account for a large share of the total. It is necessary to avoid chunk boundaries that break the integrity of professional paragraphs. This also requires adapting to differences in document volume caused by uneven update frequencies.

Configuration Settings

The parameter values provided on this page are conventional recommendations used as a starting point for configuration. Actual values are affected by material form, data volume, and business rules. Specific issues require case-by-case analysis. It is recommended to test on your own samples before finalizing settings.

Three Common Configuration Mistakes

• The embedded image field in the parsed Excel file is empty, and the interface returns a 400 BAD REQUEST error. The cause is that the PARSE_EXCEL_IMAGE configuration item is not enabled, and embedded image resources in Excel are not extracted.
• Professional parameters and units are split into different chunks after chunking, preventing large models from identifying the capacity data corresponding to "ten thousand tons/year". The cause is that the CHUNK_OVERLAP value is too low, and context association is not retained.
• Long document parsing times out, and the interface displays a "parsing failed" status code 504 GATEWAY TIMEOUT. The cause is that PARSE_FILE_TIMEOUT_SECONDS is set lower than the actual parsing time, and the long text volume of coal chemical industry research reports is not accommodated.

How to Verify Correct Configuration

• Upload a single Excel attachment of a coal chemical industry research report, and check whether the parsed result includes associated text descriptions of embedded images.
• View the chunked text fragments, and confirm that professional fields such as "coal consumption per ton" and "yuan/ton" are not forcibly split from their preceding and following text.
• Upload a single research report PDF with more than 50 pages, wait for parsing to complete, and check whether a timeout error occurs.
• Compare the original document with the parsed Markdown content, and confirm that the table structure is not flattened into plain text.

Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-14.