NB/T 11441-2023Guidelines for identification and quality evaluation of coal-measures graphite (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting.

Introduction

Graphite is widely used in refractory materials, energy storage, conductive materials, nuclear industry, military aerospace, new energy vehicles and other fields, and is an emerging strategic Minerals. The National Mineral Resources Plan (2016-2020) listed 24 types of minerals, including graphite, as strategic minerals for the first time.

Graphite is listed as one of the 35 "key minerals". Graphite can be divided into two categories. crystalline graphite and cryptocrystalline graphite (coal-based graphite). Coal-based graphite is coal.

The coal-based graphite and high-grade anthracite have continuous transition characteristics, which results in the coal-based graphite.

Due to historical reasons, the understanding of coal-bearing graphite mineralization mechanism was not in-depth enough in the past, and there was a lack of coal-bearing graphite identification standards.

The geological specifications of graphite minerals make it difficult to scientifically distinguish coal-based graphite from coal, which seriously affects the evaluation of coal-based graphite.

About 50% of the mined coal-based graphite is used as fuel, resulting in a huge waste of resources, unclear mining rights and difficult mining administration.

Therefore, it is urgent to propose coal-based graphite identification indicators and classify ore quality grades to guide my country's coal-based graphite mineral resources.

The exploration and evaluation of coal-based graphite resources will provide a basis for the management of coal-based graphite mining, promote the rational exploration and efficient development and utilization of coal-based graphite, and enhance the Strategic support capabilities for graphite demand.

This document fully absorbs the research results of coal-measure graphite genesis and resource evaluation in recent years, and uses the measured data of samples from typical coal-measure graphite mining areas across the country.

Based on the statistical analysis results, the commonly used coal rank parameters volatile matter and vitrinite reflectance are used as the preliminary criteria for distinguishing coal-based graphite from anthracite.

Preliminary identification index. using the interplanar spacing and lattice defect parameters of the aromatic structure of coal macromolecules as the accurate identification index for dividing the types of coal-based graphite.

According to the overall graphitization degree of the ore, coal-based graphite is divided into three types. No. 1, No. 2, and No. 3, and the identification index of coal-based graphite is established.

Among them, coal-based graphite No. 1 has a relatively well-developed graphite structure, and coal-based graphite No. 2 and No. 3 are equivalent to semi-graphite, belonging to anthracite and It is a transitional product between graphite and graphite. Its structural evolution and physical and chemical characteristics also have transitional properties. It has similar process properties and processing potential as graphite.

Classifying semi-graphite as a coal-based graphite mineral is beneficial to resource protection and promotes the development of coal from being mainly used as fuel to being equally used as fuel and material.

It not only promotes the development of the industry, but also provides resource guarantee for the technological innovation of coal-based graphite classification and utilization and purification and upgrading.

Based on the homology characteristics of coal-based graphite and coal, this document uses fixed carbon and sulfur content indicators to classify the two major types of ores, semi-graphite and graphite.

The quality is divided into different categories and used for coal-bearing graphite resource evaluation and quality evaluation in the geological exploration stage. Guidelines for identification and quality evaluation of coal-based graphite

1 Scope

This document specifies the general principles, sampling and testing, identification, quality grade classification and identification report of coal-based graphite.

This document applies to the identification and quality classification of coal-bearing graphite during resource evaluation, exploration and development.

2 Normative references

The contents of the following documents constitute the essential clauses of this document through normative references in this document.

For referenced documents without a date, only the version corresponding to that date applies to this document; for referenced documents without a date, the latest version (including all amendments) applies to this document.

GB/T 212 Industrial analysis methods for coal

GB/T 214 Determination of total sulfur in coal

GB/T 3520 Test method for graphite fineness

GB/T 3521 Chemical analysis methods for graphite

GB/T 6948 Microscopic determination method of vitrinite reflectance of coal

GB/T 25214 Determination of total sulfur in coal by infrared spectrometry

GB/T 30732 Industrial analysis of coal - Instrumental method

GB/T 40485 Automatic determination of random reflectance of vitrinite in coal - Image analysis method

DZ/T 0326-2018 Specification for geological exploration of graphite and crushed mica minerals

3 Terms and definitions

The following terms and definitions apply to this document.

4 General

Based on the research on coal-bearing graphite mineralization mechanism and mineral geological survey data, and based on the measured ore data, the coal-bearing graphite types are identified.

The types and quality grades of coal-bearing graphite are classified to provide a basis for the investigation, evaluation, exploration and development of coal-bearing graphite resources.

5 Sampling test