GB/T 21755-2008Chemical products for industrial use -- Determination of oxidizing properties of solids (English PDF)

Foreword

"Determination of chemical products for industrial use oxidizing properties of solids" This standard is identical with French national standards NFT20-035 (September 1985) (French version).

For ease of use, the present standard of editorial changes.

--- Increasing the "Introduction" section, the French national standards NFT20-035 "industrial use chemical oxidizing properties of solids Determination "in the" 0introduction "section included in the" Introduction "section;

--- French national standards NFT20-035 "Determination of chemical oxidizing properties of solids industrial uses" in the "9BIBLI-OGRAPHIE "as part of the standard" References "section.

Appendix A of this standard is a normative appendix.

This standard is managed by the National Standardization Technical Committee chemicals dangerous (SAC/TC251) and focal points.

Introduction

Before the implementation of this standard assay, it is recommended to first have information about the product being tested and potentially explosive nature of combustion.

The chemical structure of reviewing the product display, this product can not be the case of an exothermic reaction occurs with the fuel, the method is not applicable.

In order to ensure that this assay does not require special safety precautions should be a first test experiment.

Chemical products for industrial use Determination of oxidizing properties of solids

1 Scope

This standard specifies a method for determination of oxidizing properties of solid chemical products.

This standard does not apply to liquid products, gases, explosive or flammable products, organic peroxides, and under the experimental conditions of the method of melting the solid product (e.g., surfactants, etc.).

2 Terms and definitions

The following terms and definitions apply to this standard.

Reaction time, in seconds, under normal conditions, the reaction zone spread through a heap of work to determine the time.

Within a certain period of time, the length of the reaction zone by spreading the work stack divided by this time, expressed in millimeters per second.

Several assay mixture containing at 10% to 90% of accelerant (by weight), the measured maximum burning rate.

Principle 3

For security reasons, we should conduct a preliminary test experiment. The dried product under test with a fuel mix is \u200b\u200bintroduced into the source of the fire Observe the reaction mixture and, if intense reaction, the product can be considered as an oxidant.

If the intense reaction does not occur, continue measurement. The test sample crushed dried into a known mold with a predetermined fuel Mixed in different proportions, after the mold is made of several groups working heap.

Ignite the pile at one end work, determination of maximum burning speed, and then compare it with the reference mixture maximum burning rate.

4 Reagents

Use only analytical reagent.

4.1 barium nitrate.

Cellulose powder 4.2, thin layer chromatography using type, and satisfies the following features.

--- 85% of the fiber length between 75 m to 20µm;

--- Sieved using a 125µm sieve;

--- At a temperature of 103 °C ± 2 °C dried to constant weight.

4.3 soft wood chips (only the first test experiment), the following features.

--- Sieved using a sieve of 1.6mm;

--- Expand smaller than the layer thickness of 25mm, 2 °C 4h ± dried at a temperature of 103 °C;

--- Cooled and stored in a sealed container as far as possible within its filled.

This wood should be used in dry 24h.