Document Parsing and Chunking for Refining and Petrochemical

What this category of data looks like

Data for refining and petrochemical investment research knowledge bases comes primarily from industry association annual refining process reports, single-unit operation log documents, crude oil property analysis PDFs, refinery equipment maintenance procedures, and product yield statistics tables. Update cadence falls into two categories: periodic and real-time. Industry reports update quarterly or annually. Equipment operation logs update hourly. Document structures include long-form process manuals, structured parameter tables, and cross-format mixed documents. Professional fields and units include API gravity, distillation range temperature, sulfur content percentage, material throughput cubic meters per hour, and other specialized parameters.

Constraints on document parsing and chunking

Data characteristics for refining and petrochemical investment research impose three core constraints on document parsing and chunking. First, individual documents have significant length. Some equipment process manuals span hundreds of pages. Standard fixed-character chunking often breaks process logic. Process unit integrity must be preserved. Second, documents contain large numbers of structured tables. These include professional fields such as property parameters and yield data. Parsing must preserve the correspondence between fields and units. It avoids invalid data association after chunking. Third, data sources include cross-format documents. The system must support structure extraction from multiple formats including PDF, Excel, and Word. It ensures investment research data from different sources can be unified into the knowledge base.

How to set configurations

Configuration Item	Recommended Value	Rationale
`PARSE_FILE_TIMEOUT_SECONDS`	`300-600 seconds`	Refining documents are mostly long-form PDFs. Single-document parsing takes significant time. This range adapts to large file parsing delays
`maxChunkSize`	`800-1200 characters`	Refining documents include process steps and data tables. This range preserves complete logic for individual process units and avoids split breaks
`UPLOAD_FILE_MAX_SIZE`	`1000 MB`	Annual operation report collections for single refinery units can reach hundreds of MB. This setting adapts to large file uploads
`chunkOverlap`	`100-150 characters`	Process descriptions have parameters that span chunks. Overlapping chunks preserve context coherence
`ENABLE_TABLE_PARSE`	`Enabled`	Refining documents contain large numbers of property parameter tables. Enabling table parsing preserves the correspondence between fields and units
`defaultParseEngine`	`marker`	Refining documents mostly use complexly formatted PDFs. The marker engine has higher parsing accuracy and meets the needs of professional investment research document parsing

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

Three common misconfigurations

The symptom is a 504 Gateway Timeout response when calling the file parsing interface. The cause is failure to adjust the PARSE_FILE_TIMEOUT_SECONDS parameter. The default value is too short to complete parsing of long refining documents.
The symptom is garbled parsing results or missing fields after configuring the marker parsing engine in version 4.9.0. The cause is a parsing adaptation defect for complexly formatted PDFs in this version. Downgrade to version 4.8.20 or use the v1 marker engine.
The symptom is lost field correspondence for table data in chunking results. The cause is failure to enable the ENABLE_TABLE_PARSE configuration. The default parsing logic splits tables into scattered text. It cannot preserve unit and parameter associations for refining data.

How to verify correct configuration

Upload a single-unit process manual PDF. Check the parsing task duration and completion status. Adjust PARSE_FILE_TIMEOUT_SECONDS to a value adapted to the current document.
After parsing, review table content in chunking results. Confirm that the correspondence between parameter names, units, and numerical values is preserved. Verify that the ENABLE_TABLE_PARSE configuration is active.
Test chunking for documents of different lengths. Confirm that individual chunks contain complete process units or data nodes. Adjust maxChunkSize and chunkOverlap parameters to a reasonable range.
Call the file parsing interface. Confirm that returned chunk data includes document source identification and timestamps. Verify that metadata retention configurations are correct.

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.