ISO 24261-2:2021 微細気泡技術—サンプル特性評価のための除去方法—パート2：微細気泡除去技術 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 281 Fine bubble technology.

A list of all parts in the ISO 20480 series can be found on the ISO website.

Introduction

Fine bubble technology has recently seen growth in its application to markets such as cleaning, water treatment, agriculture and aquaculture and biomedical fields. Now methods are needed to evaluate the efficacy and efficiency of generation systems. The characteristics of most importance are the number concentration and size indices of the fine bubbles produced by such systems.

Furthermore, fine bubble dispersions in water can contain other solid and liquid particles. Contaminants such as these particles make accurate characterization of fine bubbles extremely difficult. Therefore, distinction of fine bubbles from contaminants is an urgent issue. This is also why the term index is used as it can never be 100 % established that a particle is a bubble and not a contaminant.

Currently, there are several measurement methods widely used to evaluate the number concentration index and the size index of particles. However, there are few methods to distinguish bubbles in fine bubble dispersions from other particles.

If the bubbles can be totally eliminated (with no residual bubbles) by mechanisms such as dissolution or flotation, this issue can be solved. If a method that eliminates fine bubbles in a specific size range is used, it is potentially possible to distinguish fine bubbles from other solid and liquid particles. The concentration of material after potential elimination can be compared in particle concentration index to the liquid used prior to generation. If elimination has been successful, they should be the same, and by this comparison, elimination techniques can be developed and optimized.

This document is intended to specify the most effective techniques for eliminating fine bubbles from fine bubble dispersions in water and their optimization.

1 Scope

This document specifies the elimination techniques for removing fine bubbles from fine bubble dispersion in water and how to optimize the elimination procedures to obtain better efficiency.

This document is applicable to fine uncoated bubbles (without shells).

It does not apply to fine coated bubbles (with shells).

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 20480-1 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

Bibliography