Rubber and rubber products — Determination of combustion energy and carbon dioxide emission from biobased and non-biobased materials

ISO 20463:2018 specifies the measuring methods of the combustion energy (i.e. gross calorific value) and the carbon dioxide emission amount from biobased and non-biobased materials in rubber or rubber products. ISO 20463:2018 applies to rubber and rubber products (including polyurethane) such as raw materials, materials and final products.

Élastomères et produits à base d'élastomères — Méthode de détermination de l'énergie de combustion et de l'émission de CO2 des matériaux biosourcés et non biosourcés

General Information

Status
Published
Publication Date
05-Apr-2018
Current Stage
6060 - International Standard published
Start Date
06-Apr-2018
Completion Date
06-Apr-2018
Ref Project

Buy Standard

Standard
ISO 20463:2018 - Rubber and rubber products -- Determination of combustion energy and carbon dioxide emission from biobased and non-biobased materials
English language
20 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (sample)

INTERNATIONAL ISO
STANDARD 20463
First edition
2018-04
Rubber and rubber products —
Determination of combustion energy
and carbon dioxide emission from
biobased and non-biobased materials
Élastomères et produits à base d'élastomères — Méthode de
détermination de l'énergie de combustion et de l'émission de CO des
matériaux biosourcés et non biosourcés
Reference number
ISO 20463:2018(E)
ISO 2018
---------------------- Page: 1 ----------------------
ISO 20463:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018

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: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 20463:2018(E)
Contents Page

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

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

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

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

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

4 Principle ........................................................................................................................................................................................................................ 2

5 Sampling ........................................................................................................................................................................................................................ 3

6 Determination of the combustion energy of biobased and non-biobased materials ...................3

6.1 General ........................................................................................................................................................................................................... 3

6.2 Reagents and materials ................................................................................................................................................................... 3

6.3 Apparatus .................................................................................................................................................................................................... 3

6.4 Procedure .................................................................................................................................................................................................... 6

6.5 Calculation method of biobased and non-biobased combustion energy ............................................. 7

7 Determination of the amount of carbon dioxide emission from biobased and non-

biobased materials ............................................................................................................................................................................................. 7

7.1 General ........................................................................................................................................................................................................... 7

7.2 Apparatus .................................................................................................................................................................................................... 7

7.3 Reagents........................................................................................................................................................................................................ 8

7.4 Procedure .................................................................................................................................................................................................... 8

7.4.1 Verification of the measurement ........................................................................................................................ 8

7.4.2 Transfer of the combustion gas to a gas sampling bag from bomb ...................................... 9

7.4.3 Measurement of carbon dioxide concentration by GC .................................................................... 9

7.4.4 Determination of the total volume of the combustion gas .......................................................10

7.4.5 Measurement of the room temperature and the atmospheric pressure ......................11

7.4.6 Calculation of the amount of carbon dioxide emission ...............................................................11

7.5 Calculation of biobased and non-biobased carbon dioxide emission ..................................................12

8 Precision ....................................................................................................................................................................................................................12

9 Test report ................................................................................................................................................................................................................12

Annex A (informative) Calculation of net calorific value for combustion energy...............................................13

Annex B (informative) Examples of determination of combustion energy of biobased and

non-biobased materials .............................................................................................................................................................................15

Annex C (normative) Saturated water vapour pressure ...............................................................................................................16

Annex D (informative) Determination of the amount of carbon dioxide emission from

biobased and non-biobased materials .......................................................................................................................................17

Annex E (informative) Precision ............................................................................................................................................................................18

Bibliography .............................................................................................................................................................................................................................20

© ISO 2018 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 20463:2018(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 45, Rubber and rubber products,

Subcommittee SC 2, Testing and analysis.
iv © ISO 2018 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 20463:2018(E)
Introduction

To reduce the use of exhaustible fossil resources such as petroleum, coal, or natural gas, as well as the

amount of carbon dioxide emission from those during rubber production process or waste disposal, it is

very important to shift the raw materials from fossil-based resources to “biomass” resources. Biomass

includes starch, cellulose, hemicellulose or lignin which living plants photosynthesize converting the

carbon dioxide in the atmosphere. It is preferred to utilize inedible biomass such as agricultural waste

or food-industries’ wastes rather than using edible biomass. Using biobased resources instead of fossil-

based ones will benefit to make sustainable social systems and to preserve the global environment.

Products that are produced fully or partially from biomass resources are “biobased” products. Many

rubber products today include natural rubber as component, so there are many biobased products in the

rubber market already. That is a great advantage for the rubber industry to contribute to sustainable

social systems.

Recycling chemical products is an important act to preserve limited resources, and basically there are

two ways to recycle end-of-life rubber products, i.e. “material recycling” and “thermal recycling”. It is

useful to develop concrete indices to evaluate the effect of thermal recycling.

This document specifies how to determine the biobased combustion energy and the amount of biobased

carbon dioxide emission hoping to promote rubber-product waste as an alternative fuel.

This document introduces the idea of biobased combustion energy as an index to examine the degree

of contribution of thermal recycling of rubber wastes. At the same time, the amount of biobased carbon

dioxide emission from the thermal recycling process will act as a direct comparison to the fossil-based

carbon dioxide emission.
© ISO 2018 – All rights reserved v
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 20463:2018(E)
Rubber and rubber products — Determination of
combustion energy and carbon dioxide emission from
biobased and non-biobased materials

WARNING 1 — Persons using this document should be familiar with normal laboratory practice.

This document does not purport to address all of the safety problems, if any, associated with its

use. It is the responsibility of the user to establish appropriate safety and health practices and to

determine the applicability of any other restrictions.

WARNING 2 — Certain procedures specified in this document might involve the use or generation

of substances, or the generation of waste, that could constitute a local environmental hazard.

Reference should be made to appropriate documentation on safe handling and disposal after use.

1 Scope

This document specifies the measuring methods of the combustion energy (i.e. gross calorific value)

and the carbon dioxide emission amount from biobased and non-biobased materials in rubber or rubber

products.

This document applies to rubber and rubber products (including polyurethane) such as raw materials,

materials and final products.
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.

ISO 1382, Rubber — Vocabulary

ISO 1795, Rubber, raw natural and raw synthetic — Sampling and further preparative procedures

ISO 1928, Solid mineral fuels — Determination of gross calorific value by the bomb calorimetric method

and calculation of net calorific value

ISO 4661-2, Rubber, vulcanized — Preparation of samples and test pieces — Part 2: Chemical tests

ISO 19984-2, Rubber and rubber products — Determination of biobased content — Part 2: Biobased

carbon content
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 1382 and the following apply.

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

— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1
biobased component

biobased part of a biobased constituent which is wholly or partly from biomass resource(s)

[SOURCE: ISO 19984-1:2017, 3.2]
© ISO 2018 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO 20463:2018(E)
3.2
biobased carbon content
biobased component(s) (3.1) in a product expressed by carbon% to total carbon
[SOURCE: ISO 19984-1:2017, 3.4]
3.3
biomass

material of biological origin excluding material embedded in geological formations and/or fossilized

[SOURCE: ISO 19984-1:2017, 3.6]
3.4
biobased combustion energy

energy obtained from the combustion of the biobased carbon contained in rubber or a rubber product

Note 1 to entry: The combustion energy is measured as gross calorific value or net calorific value.

Note 2 to entry: The biobased combustion energy is expressed in J/g, or calorific value (joules, J) per sample

mass (g).
3.5
biobased carbon dioxide emission

amount of carbon dioxide emitted from the biobased carbon contained in rubber or a rubber product

Note 1 to entry: The biobased carbon dioxide emission is expressed in g/g, or emitted carbon dioxide amount (g)

per sample mass (g).
3.6
gross calorific value

absolute value of the specific energy of combustion, for unit mass of rubber or rubber-product sample

burned in oxygen in a calorimetric bomb under specified conditions

Note 1 to entry: The products of combustion are assumed to consist of gaseous oxygen, nitrogen, carbon dioxide

and sulfur dioxide, of liquid water (in equilibrium with its vapour) saturated with carbon dioxide under the

conditions of the bomb reaction, and of solid ash, all at the reference temperature.

Note 2 to entry: The gross calorific value is expressed in J/g.
3.7
net calorific value

absolute value of the specific energy of combustion, for unit mass of rubber or rubber-product sample

burned in oxygen in a calorimetric bomb under such conditions that all the water of the reaction

products remains as water vapour, the other products being as for the gross calorific value (3.6), all at

the reference temperature
Note 1 to entry: The net calorific value is expressed in J/g.
4 Principle

A sample from rubber or a rubber product is completely combusted in a pressure-proof sealed vessel

(bomb) with high pressure oxygen gas settled in an insulated area. The combustion energy of the

sample is calculated from the increased heat in the insulated area. The carbon dioxide emission amount

is determined by measuring both the combustion gas volume collected from the used bomb and its

carbon dioxide concentration.

The biobased combustion energy and the biobased carbon dioxide emission can be calculated in

proportion by multiplying the obtained values by the biobased carbon content.

NOTE There are two kinds of combustion energies, i.e. gross calorific value and net calorific value (see

Annex A for information). This document specifies the determination of gross calorific value of rubber and

rubber products.
2 © ISO 2018 – All rights reserved
---------------------- Page: 7 ----------------------
ISO 20463:2018(E)
5 Sampling

For raw rubber, carry out sampling in accordance with ISO 1795. For vulcanized rubber, carry out

sampling in accordance with ISO 4661-2.
6 Determination of the combustion energy of biobased and non-biobased
materials
6.1 General

This method specifies how to determine the combustion energy of rubber or a rubber product using

a bomb calorimeter. A high-pressure proof sealed bomb is used as a measuring vessel. A test sample

is placed in the bomb filled with high-pressure oxygen with an ignition wire contacting the sample.

The bomb is then placed in a water vessel the temperature of which is accurately controlled and

measured. The test sample is combusted by igniting the wire and the calorific value is determined by

the temperature increase, the volume of water in the water vessel (or the heat capacity of calorimeter)

and the heat capacity of the bomb.

The combustion system is calibrated by combusting the calorimetric standard, i.e. certified benzoic acid.

If the carbon dioxide emission amount is to be measured in the later process, the combustion gas in the

bomb shall be collected and used for the determination.
6.2 Reagents and materials

6.2.1 Oxygen, at a pressure high enough to fill the bomb to 3 MPa, pure, with an assay of at least 99,5 %

volume fraction, and free from combustible matter.

NOTE Oxygen made by the electrolytic process can contain up to 4 % volume fraction of hydrogen.

6.2.2 Benzoic acid, of calorimetric-standard quality, certified by (or traceable to) a recognized

standardizing authority.
6.3 Apparatus
6.3.1 Bomb calorimeter

The calorimeter (see Figure 1) consists of the assembled combustion bomb, the calorimeter can (with or

without a lid), the calorimeter stirrer, water, temperature sensor and leads with connectors inside the

calorimeter can required for ignition of the sample or as part of temperature measurement or control

circuits. The calorimeter shall conform to ISO 1928 or provide the equivalent test results. During

measurements, the calorimeter is enclosed in a thermostat. The manner in which the thermostat

temperature is controlled defines the working principle of the instrument and, hence, the strategy for

evaluating the corrected temperature rise.
© ISO 2018 – All rights reserved 3
---------------------- Page: 8 ----------------------
ISO 20463:2018(E)
Key
1 thermostat lid 4 calorimeter can
2 ignition leads 5 thermostat
3 thermometer 6 stirrer
Figure 1 — Classical-type combustion-bomb calorimeter with thermostat

6.3.2 Combustion bomb, capable of withstanding safely the pressures developed during combustion;

see Figures 1 and 2.

The material of construction shall resist corrosion by the acids produced in the combustion of rubber

or a rubber product. A suitable internal volume of the bomb is from 250 ml to 350 ml and it is preferred

that the bomb is equipped with a relief valve or a bursting disc.

WARNING — Bomb parts shall be inspected regularly for wear and corrosion; particular

attention shall be paid to the condition of the threads of the main closure. Manufacturers’

instructions regarding the safe handling and use of the bomb shall be observed. When more

than one bomb of the same design is used, it is imperative to use each bomb as complete unit.

Colour coding is recommended. Swapping of parts can lead to a serious accident.
4 © ISO 2018 – All rights reserved
---------------------- Page: 9 ----------------------
ISO 20463:2018(E)
Key
1 valve cover 4 closure ring
2 valve housing 5 sealing ring
3 cap 6 vessel body
Figure 2 — Typical calorimeter bomb
6.3.3 Fuse

6.3.3.1 Ignition wire, of nickel-chromium 0,10 mm to 0,20 mm in diameter, platinum 0,05 mm to

0,10 mm in diameter, or another suitable conducting wire with well characterized thermal behaviour

during combustion.
6.3.3.2 Cotton fuse, of white cellulose cotton, or equivalent.
6.3.4 Pressure regulator, to control the filling of the bomb with oxygen.

6.3.5 Pressure gauge (e.g. 0 MPa to 6 MPa), to indicate the pressure in the bomb with a resolution of

0,05 MPa.

6.3.6 Relief valve or bursting disc, operating at 3,5 MPa, and installed in the filling line, to prevent

overfilling the bomb.

CAUTION — Equipment for high-pressure oxygen shall be kept free from oil and grease. Do not

test or calibrate the pressure gauge with hydrocarbon fluid.

6.3.7 Balance, capable of weighing the sample, ignition wire, etc., with a resolution of at least 0,1 mg.

© ISO 2018 – All rights reserved 5
---------------------- Page: 10 ----------------------
ISO 20463:2018(E)
6.4 Procedure
6.4.1 Preparation of test sample

Weigh out 0,3 g to 0,8 g of the sample to the nearest 0,1 mg. Block, sheet, powder or liquid sample can be

used. The amount of sample shall correspond to the measurable energy range of the calorimeter used.

6.4.2 Calibration of calorimeter

Weigh approximately 1 g of benzoic acid pellet certified for combustion energy measurement and place

it on a combustion dish in the bomb. Settle an ignition wire so that it touches this pellet and connects to

the ignition electrode of the ignition circuit. Close the vessel body and tighten the closure ring firmly.

Connect the pipe from the oxygen pressure regulator to the valve of the combustion bomb. The pipe shall

be certified to perform under 3,5 MPa pressure and have a branched purge line with an on-off valve.

Open the bomb valve and control the regulator to gradually fill oxygen in the bomb. When the pressure

reaches 2,5 MPa to 3,0 MPa, close both the bomb valve and the regulator valve, and remove the pipe

from the bomb.

Immerse the sealed, assembled bomb in the water vessel. Watch for babbles in water and make sure

there is no oxygen leak.

When the water temperature has become stable, combust the benzoic acid pellet by applying voltage to

the ignition wire.

Adjust the obtained combustion energy as 26 460 J/g of benzoic acid. Repeat the same procedure for

another pellet until two consecutive measured values fall within 26 460 J/g ± 80 J/g.

6.4.3 Measurement of combustion energy

Place the accurately weighed test sample (6.4.1) on the combustion dish in the bomb. Settle the ignition

wire so that it touches the sample and connects to the ignition electrode of the ignition circuit. Close the

vessel body and tighten the closure ring firmly.

Connect the pipe from the oxygen pressure regulator to the valve of the combustion bomb. The pipe shall

be certified to perform under 3,5 MPa pressure and have a branched purge line with an on-off valve.

When the amount of carbon dioxide emission is to be measured afterwards (see Clause 7), purge the

inside air with oxygen. To do that, connect an oxygen bottle, introduce ca. 0,2 MPa oxygen and evacuate

the oxygen and the inside air together either by removing the pipe or by using the branched purge line.

Repeat the process at least twice.

Open the bomb valve and control the regulator to gradually fill oxygen in the bomb. When the pressure

reaches 2,5 MPa to 3,0 MPa, close both the bomb valve and the regulator valve, and remove the pipe (if

a purge line is equipped, release oxygen before removing the pipe).

Immerse the sealed, assembled bomb in the water vessel. Watch for babbles in water and make sure

there is no oxygen leak.

When the water temperature has become stable, combust the test sample by applying voltage to the

ignition wire. Read the measured value for combustion energy.

Repeat the measurement procedure for the same test sample and compare the results. When the difference

falls into ±160 J/g, finish the measurement and take the mean value as the total combustion energy.

6.4.4 Measurement of biobased carbon content

To determine the biobased combustion energy (E ) of the test sample, information on its biobased

carbon content (x ) is indispensable. If the sample's chemical formulation and the resource of each

6 © ISO 2018 – All rights reserved
---------------------- Page: 11 ----------------------
ISO 20463:2018(E)

component (i.e. the biobased carbon content of each component) is available, the biobased carbon

content of the sample can be calculated in accordance with ISO 19984-1. When those are unavailable,

the biobased carbon content shall be measured in accordance with ISO 19984-2.
6.5 Calculation method of biobased and non-biobased combustion energy

The biobased combustion energy (E ) can be calculated by applying the total combustion energy (E)

measured in 6.4.3 to Formula (1). Non-biobased combustion energy (E ) can be derived by subtracting

E from E. This calculation is based on the fact that the combustion energy is in proportion to the total

carbon amount in a product, which is the sum of biobased and fossil-based (non-biobased) carbon

amounts.
E = E × x/100 (1)
B B
where
E is the biobased combustion energy (J/g);
E is the combustion energy (gross calorific value) (J/g);
x is the biobased carbon content (%).

Examples of results for measuring and calculating of combustion energy are shown in Annex B.

The biobased carbon content, x , i.e. the ratio of the biobased carbon to the total carbon in rubber or

a rubber product, can be calculated in accordance with ISO 19984-1 when the chemical formulation

and the information of each component are known. When no such information is available, it can be

determined in accordance with ISO 19984-2.

If any materials are used at the time of combustion such as ignition wires, combustion improvers or

sample holders, the combustion energy of those should be measured in advance. Then the value shall be

subtracted from the whole value to obtain the true amount of the combustion energy of the test sample.

7 Determination of the amount of carbon dioxide emission from biobased and
non-biobased materials
7.1 General

This clause specifies the method to determine the amount of carbon dioxide emission from rubber or

rubber products as well as the combustion energy measurement (see Clause 6). The carbon dioxide and

the oxygen are collected in a gas sampling bag from the bomb, and the carbon dioxide emission amount

is determined from its concentration and the volume ratio compared to the total gas collected.

The gas analysing system is calibrated by the reference gas with certified concentration of carbon

dioxide in nitrogen gas. The validity of this measurement is confirmed by the amount of carbon dioxide

emission from benzoic acid used as a calorimetric standard.
7.2 Apparatus

7.2.1 Gas sampling bag, sufficient enough for combustion gas volume in the bomb under atmospheric

pressure (preferably of 10 l to 20 l size), with a cock. If the sample gas is to be inserted by a micro syringe

to the gas chromatograph (7.2.2), it is recommended to use a bag with a rubber-septum-mounted

sampling port.
7.2.2 Gas chromatograph (GC), with the following specifications:

― detector, i.e. thermal conductive detector (TCD) or helium ionization detector (HID);

© ISO 2018 – All rights reserved 7
---------------------- Page: 12 ----------------------
ISO 20463:2018(E)

― column, such as molecular sieve, active carbon, or porous polymer (ethylvinylbenzene-

divinylbenzene) column, to separate carbon dioxide and other gases;

― injector, a septum rubber port for the gas tight syringe or a gas sample injector with a gas sampling

valve and a sample loop, of the volume of the gas to be determined (0,5 ml to 1,0 ml).

7.2.3 Gas volume meter, capable to measure gas volume (of carbon dioxide and other gases) over 30 l

with resolution of 10 ml.

7.2.4 Vacuum sampling bottles, of 100 ml and 1,0 l volume, to prepare the gas for calibration curve

with determined concentration of standard carbon dioxide gas in inert dilution gas such as oxygen or

nitrogen gas.

7.2.5 Gas tight syringes, of 5 ml and 20 ml volume, to dilute the standard carbon dioxide inserting to

vacuum sampling bottle or inject the gas to GC.

7.2.6 Vacuum pump, of 10 l/min to 20 l/min exhaust velocity, to evacuate the remaining gas in the

tube, the cock and the gas sampling bag connected to the bomb.

7.2.7 Air pump, of 1 l/min to 2 l/min speed to meet the gas volume meter specification, to transfer the

gas from the gas sampling bag to the gas volume meter.
7.2.8 Thermometer, capable to measure the room temperature to the nearest 1 °C.

7.2.9 Atmospheric pressure meter, capable to measure the atmospheric pressure to the nearest

0,1 kPa.
7.3 Reagents

7.3.1 Standard gas (carbon dioxide), to calibrate the gas chromatograph, with an assay of at least

99,9 % volume fraction, traceable to national standards.
Observe the manufacturer's expiry date or recommended shelf-
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.