ISO/PRF 20480-4

Fine bubble technology -- General principles for usage and measurement of fine bubbles

Technologie des fines bulles -- Principes généraux pour l'utilisation et la mesure des fines bulles

Standards Content (sample)

DRAFT INTERNATIONAL STANDARD
ISO/DIS 20480-4
ISO/TC 281 Secretariat: JISC
Voting begins on: Voting terminates on:
2020-01-13 2020-04-06
Fine bubble technology — General principles for usage and
measurement of fine bubbles —
Part 4:
Terminology related to microbubble beds
ICS: 01.040.07; 07.030
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
This document is circulated as received from the committee secretariat.
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 20480-4:2020(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2020
---------------------- Page: 1 ----------------------
ISO/DIS 20480-4:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/DIS 20480-4:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

Bibliography ................................................................................................................................................................................................................................ 5

© ISO 2020 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/DIS 20480-4:2020(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following

URL: www .iso .org/ iso/ foreword .html.

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

A list of all parts in the ISO 20304 series can be found on the ISO website.
iv © ISO 2020 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/DIS 20480-4:2020(E)
Introduction

Flotation process to separate the desired minerals from the gangue was started over 2000 years ago

by Greeks. As the one of the flotation processes, dissolved air flotation (DAF) was used mainly in

applications in which the material to be removed, such as fat, oil, fibres, and grease from water, initially.

In the late 1960s, however, the process also became acceptable for wastewater and potable water

treatment applications (Letterman and AWWA, 1999).

DAF has been used as an effective alternative to the more conventional separation process of sediments.

The sedimentation process removes particles by submerging them on the floor, while the DAF process

utilizes fine bubbles to float on water. Particles floating on the water surface are finally collected

through a scraper. Through DAF, low-density flocs can be removed using fine bubbles. Compared to

conventional sedimentation processes, DAF has the following advantages: it is an efficiency process,

because of high hydraulic loading rates (Amato et al., 2013; AWWA, 2011).

There are various factors that affect the treatment efficiency of the DAF process, such as air saturation,

bubbles and particles size, coagulant, and so on. Among them is the bubble bed. To increase the

treatment capacity, DAF has been developed as bubble bed become thicker by increasing in the depth of

the flotation ba
...

INTERNATIONAL ISO
STANDARD 20480-4
First edition
Fine bubble technology — General
principles for usage and measurement
of fine bubbles —
Part 4:
Terminology related to microbubble
beds
PROOF/ÉPREUVE
Reference number
ISO 20480-4:2020(E)
ISO 2020
---------------------- Page: 1 ----------------------
ISO 20480-4:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii PROOF/ÉPREUVE © ISO 2020 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 20480-4:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

Bibliography ................................................................................................................................................................................................................................ 5

© ISO 2020 – All rights reserved PROOF/ÉPREUVE iii
---------------------- Page: 3 ----------------------
ISO 20480-4:2020(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

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

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
A list of all parts in the ISO 20304 series can be found on the ISO website.
iv PROOF/ÉPREUVE © ISO 2020 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 20480-4:2020(E)
Introduction

The flotation process to separate the desired minerals from the gangue started over 2 000 years ago in

Ancient Greece. As the one of the flotation processes, dissolved air flotation (DAF) was used mainly in

applications in which the material to be removed, such as fat, oil, fibres and grease from water, initially.

In the late 1960s, however, the process also became acceptable for wastewater and potable water

[3]
treatment applications.

DAF has been used as an effective alternative to the more conventional separation process of sediments.

The sedimentation process removes particles by submerging them on the floor, while the DAF process

utilizes fine bubbles to float on water. Particles floating on the water surface are finally collected

through a scraper. Through DAF, low-density flocs can be removed using fine bubbles. Compared to

conventional sedimentation processes, DAF has the advantage of being an efficient process because of

[4]
high hydraulic loading rates.

There are various factors that affect the treatment efficiency of the DAF process, such as air saturation,

bubbles and particles size, coagulant, etc. Among them is the bubble bed. To increase the treatment

capacity, DAF has been developed as bubble bed become thicker by increasing in the depth of the

flotation basin.

NOTE A coagulant is a chemical that causes coagulation to increase particles size during water treatment

process.

Even though the characteristics of bubble bed influence on the removal efficiency of DAF process, it was

[6]

not possible to observe the bubble bed depth in full-scale DAF tanks until few years ago. Recently, new

theories and techniques were developed for measurement and evaluation of the bubble bed in full-scale

DAF tank. However, these technologies are not yet widely applied in
...