ISO 7404-4:2025 PDF

Name: ISO 7404-4:2025 — Coal — Methods for petrographic analysis — Part 4: Method of determining microlithotype, carbominerite and minerite composition
SKU: ISO 7404-4:2025
Price: 25 EUR
Availability: InStock

Coal — Methods for petrographic analysis — Part 4: Method of determining microlithotype, carbominerite and minerite composition

Название (английский):

ISO 7404-4:2025

Coal — Methods for petrographic analysis — Part 4: Method of determining microlithotype, carbominerite and minerite composition

Статус документа:: Действующий
Формат:: Электронный (PDF)
Количество страниц:: 9
Дата публикации:: 27 октября 2025 г.
Издание:: ISO IS 7404 edition 3 version 1
ICS:: 73.040

Тип поставки:

Full version135 €Read online 24h10 €Read online 72h15 €

Язык документа:

ruen

Срок поставки:2 раб. дн. (перевод)

Цена:135 €

Описание (английский):

This document specifies a method, using a graticule with 20 crossline intersections, for determining the proportions of microlithotypes, carbominerite and minerite in coals. It applies only to determinations made on polished particulate blocks using reflected white light. Additional blue, blue-violet or UV light excitation for better identification of liptinite in fluorescence can be used especially for low rank coals.

Abstract

Похожие стандарты

Стандарты, упомянутые в описании

Overview

ISO 7404-4:2025 - Coal - Methods for petrographic analysis - Part 4 specifies a standardized point-count method for determining the proportions of microlithotypes, carbominerite and minerite in coal. The method uses a graticule with 20 crossline intersections on polished particulate blocks observed in reflected white light, with optional blue/blue‑violet/UV excitation to assist liptinite identification by fluorescence (useful for low‑rank coals).

Key topics and technical requirements

Sampling & preparation: Analysis applies to polished particulate blocks prepared in accordance with ISO 7404-2.

Optical setup: Reflected‑light microscope with immersion objective (25×–60×) and eyepiece (8×–12×) that accepts a graticule; immersion medium with suitable refractive index (recommended n = 1.5180 as per ISO 7404-5).

Graticule/grid: A 20‑intersection grid with an effective 50 µm distance between extreme intersections in x and y directions, ensuring compliance with the 5% volume fraction and 50 µm minimum size rules for microlithotype identification.

Point count rules:

A point is accepted only if at least 10 of the 20 intersections fall on a single particle; points with fewer intersections are recorded as rejected.
Rejected points must not exceed 10% of total accepted + rejected points; excess fines indicate poor sample preparation.

Mineral-matter thresholds: Table-based limits define when a particle is a microlithotype versus a carbominerite or minerite (e.g., for 16–20 intersections within a particle, up to 3 intersections on carbonate/clay/quartz permitted; sulfide intersections must be 0).

Microlithotype definitions: Allocation rules for vitrite, liptite, inertite, clarite, durite, vitrinertite and trimacerite based on distribution of maceral groups under intersections (see ISO 7404-3 for maceral ID).

Stage movement & counting: Mechanical/scanning stage advances in steps (step length ≈ half maximum particle diameter; example 0.5–0.6 mm for 1 mm top size) to avoid double counting. Results and precision (repeatability/reproducibility) are reported.

Applications and users

ISO 7404-4:2025 is used by:

Coal petrologists and analytical laboratories performing coal petrographic analysis

Geologists and mining engineers for seam correlation, coal genesis studies and stratigraphic work

Coal preparation and quality control teams to assess hardness, density, mineral content and behavior in processing and combustion

Researchers evaluating maceral associations and their influence on coal utilization

Practical benefits include consistent microlithotype quantification for process modelling, quality assurance, and comparative studies across laboratories.

Related standards

ISO 7404-1: Vocabulary for coal petrography

ISO 7404-2: Sample preparation (particulate block preparation)

ISO 7404-3: Maceral group identification and composition

ISO 7404-5: Recommendations for immersion media and reflectance measurement

Keywords: ISO 7404-4:2025, coal petrographic analysis, microlithotype, carbominerite, minerite, graticule, point count, reflected light microscope, liptinite, vitrinite, inertinite.

ISO 7404-4:2025 PDF

Abstract

Похожие стандарты

Overview

Key topics and technical requirements

Applications and users

Related standards

Технические детали

ISO 7404-2:1985

Methods for the petrographic analysis of bituminous coal and anthracite — Part 2: Preparation of coal samples

ISO 7404-5:1994

Methods for the petrographic analysis of bituminous coal and anthracite — Part 5: Method of determining micro…

ISO 7404-3:1994

Methods for the petrographic analysis of bituminous coal and anthracite — Part 3: Method of determining macer…

ISO 7404-1:1994

Methods for the petrographic analysis of bituminous coal and anthracite — Part 1: Vocabulary