ISO/TR 23891:2020

TECHNICAL ISO/TR
REPORT 23891
First edition
Plastics — Recycling and recovery —
Necessity of standards
Plastiques — Recyclage et valorisation — Nécessité des normes
PROOF/ÉPREUVE
Reference number
ISO/TR 23891:2020(E)
©
ISO 2020

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ISO/TR 23891:2020(E)

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Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Overview prerecycling plastic technologies . 1
4.1 General considerations related to recycling . 1
4.1.1 Process into the polymer resins . 1
4.1.2 Design for sustainability . 1
4.1.3 Additives . 2
4.2 Plastics processing and conversion . 2
4.2.1 Blow moulding . 2
4.2.2 Compression moulding . 3
4.2.3 Extrusion . 3
4.2.4 Injection moulding . 3
4.2.5 Reaction injection moulding (RIM) . 3
4.2.6 Thermoforming . 3
4.2.7 Transfer moulding . 4
5 Brief overview of plastic waste management . 4
5.1 Waste management . 4
5.2 Overview of the supply chain uptaking recycled plastics . 6
6 Inventory of existing standards (national, regional and global) . 6
6.1 General . 6
6.2 ISO/TC 61, Plastics, SC 14, Environmental aspects . 6
6.3 CEN/TC 249, Plastics . 7
6.4 ISO/TC 122/SC 3, Performance requirements and tests for means of packaging,
packages and unit loads, ISO/TC 122/SC 4, Packaging and environment and
CEN/TC 261/SC 4, Packaging and the environment . 7
6.5 ASTM Subcommittee D20.95 on Recycled Plastics (USA) . . 8
6.6 UNI (Italy) . 9
6.7 BIS (India) .10
6.8 JISC (Japan) .10
7 General description of mechanical and chemical recycling techniques .11
7.1 Material recovery .11
7.2 Mechanical recycling .11
7.2.1 General.11
7.2.2 Preparatory activities for mechanical recycling .11
7.2.3 Mechanical recycling process .11
7.3 Chemical recycling feedstock recovery .12
8 Mapping of relevant challenges .13
8.1 General .13
8.2 Lack of standards .13
8.2.1 Calculating recycling rate .13
8.2.2 Right choice of recycling method.14
8.2.3 Quality and properties of recyclates .14
8.2.4 Renewable and recycled feedstock .14
8.2.5 Resource efficiency .14
8.2.6 Traceability and marking in design stage .14
9 Necessity of standards — Background for necessity based on challenges with
missing standards, list up .15
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Annex A (informative) Additives and functions .16
Annex B (informative) Participating cities .18
Bibliography .24
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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 61, Plastics, Subcommittee SC 14,
Environmental aspects.
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.
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Introduction
Facing resource consumption beyond the capacity of the global ecosystem, the complex challenges
connected to the plastics recycling must be overcome globally. It is more efficient that processes and
a better management of waste indicate the most obvious potential to increase resource efficiency.
This management can be achieved by reducing waste or by reusing, or recycling of the waste. Plastics
waste entering a formal waste management system, are usually recycled, incinerated or disposed
of in landfill. However, in communities where a formal waste management system does not exist, a
substantial proportion of plastics waste is disposed of in uncontrolled dumps, watercourses, or burned
openly (UNEP, 2016). Different kinds of plastics included in plastic waste, must be reused, collected and
recycled to a much higher degree than today. Therefore, an agreement for this work and identification
of the necessity of standards in the plastics recycling system and giving direction for the adoption
of regional standards and/or the developing of new and existing standards took place at ISO/TC 61
Plastics-meeting in Japan 2018 and gave the reason for the work on this document.
This document has been developed to assist all plastics industry stakeholders in the development of
new and improved standards for plastic recycling.
It gives a short general introduction to plastic recycling and describes the process from feedstock to
plastics, the different types of recycling technologies and highlights common problems in relation to
recycling of plastic materials and products. Both fossil and non-fossil feedstock are discussed.
In Clause 6, existing standards are mapped. In Clause 8, challenges in the transition to a sustainable
plastic system are discussed. The necessity of standards is identified in Clause 9.
The overall structure of this document is as follows:
— brief overview of the current situation;
— general description of recycling techniques;
— inventory of existing standards (national, regional and global);
— mapping of relevant challenges;
— necessity of standards.
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TECHNICAL REPORT ISO/TR 23891:2020(E)
Plastics — Recycling and recovery — Necessity of
standards
1 Scope
This document gives a brief overview of the current (2019) situation in plastic recycling systems,
relevant existing standards and short description of different recycling techniques. It aims to identify
the necessity of standards in the plastics recycling system and give direction for the adoption of
regional standards and/or the development of new and existing standards.
This document addresses various recycling options, with focus on, but not limited to, mechanical
recycling, chemical and/or feedstock recycling and the corresponding preparatory activities.
This document excludes organic recycling (also designated as biological recycling) and energy recovery.
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 472, Plastics — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Overview prerecycling plastic technologies
4.1 General considerations related to recycling
4.1.1 Process into the polymer resins
Polymer resins in a bulk state which go through a thermal or chemical process (whether it is the
moulding of thermosetting plastics, extrusion, injection moulding or film blowing of thermoplastics or
spinning of a fibre from the melt) undergo deformation by applied forces. It means that the finished
article is subjected to stress. Since plastics are a large group of similarly based but significantly
different materials, the process has various effects on their short- and long -term behaviours. These
effects should be considered during design and recycling of a plastic component or product before and
after each lifecycle.
4.1.2 Design for sustainability
Design for sustainability includes selecting a proper material composition for a particular application.
It is essential to define the properties not only to the performance of the component or product during
usage phase, but also to its recycling and the next lifecycle. Design of a particular application should
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also cover recycling process. Plastics and products containing plastics should be designed for reuse,
durability beyond their usage period, and recyclability. Design for an application should consider the
whole life cycle including end-of-life with dismantling, chemical composition of plastics and their
suitability to be reused in order to minimize barriers in recycling and for the next lifecycle.
4.1.3 Additives
Additives are essential ingredients in plastics which can make a difference between the success and
failure for all plastics value chain and, of course, on the recycling’s part. Additives can help or destroy
the recycling of plastics depending on synergic or antagonistic effects. A general concern with additives
is the lack of transparency and information about what additives are being used in different materials.
This may reduce the appeal of recycled plastics use in products. Added to the issues of the additives,
there is local legislation limiting the plastic recycling and in some cases with amendment to legislation.
Table 1 shows the proportion of additives by type used in global plastics resin (non-fibre) waste based
on estimated additives used between 2000 and 2014 (See Reference [1]).
Table 1 — Proportion of additives by type used in global plastics resin (non-fibre) waste based
on estimated additives used between 2000 and 2014, and waste in 2015
Additive type Proportion of additives in global plastics Mass of additives that became
production 2000–2014 (%) waste in 2015 (tonnes)
Plasticisers 34 7,2
Fillers 28 5,9
Flame retardants 13 2,7
Antioxidants 6 1,3
Heat Stabilizers 5 1,1
Impact modifiers 5 1,1
Other 4 0,8
Colourants 2 0,4
Lubricants 2 0,4
Light stabilizer 1 0,2
Totals 100 21,1
Some common additives are presented in Annex A, Table A.1.
4.2 Plastics processing and conversion
4.2.1 Blow moulding
Blow moulding is used when the plastic item to be created needs to be hollow. A molten tube is created
with blow moulding by using compressed air, which blows up the tube and forces it to conform to the
chilled mould. Variations of blow moulding include injection, injection-stretch, and extrusion blow
moulding.
Injection blow moulding uses a preform, which is taken to a blow mould, heated and filled with
compressed air. As a result, it conforms to the interior design of the blow mould. With injection-stretch
blow moulding, the plastic is stretched prior to being formed. Otherwise, it is essentially the same as
the injection process.
With continuous extrusion, a molten plastic tube is continuously created. At the appropriate times,
the tube is pinched between two mould halves. Then, a needle or a blow pin is inserted into the tube
and blows compressed air up the part to force it to conform to the mould interior. With accumulator
extrusion, the molten plastic material is gathered in the chamber before it is forced through a die to
form a tube.
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4.2.2 Compression moulding
Compression moulding is the most common process used with thermosetting materials and is usually
not used for thermoplastics. With this process, the material is squeezed into its desired shape with
the help of pressure and heat. Plastic moulding powder and other materials are added to the mix in
order to create special qualities or to strengthen the final product. When the mould is closed and
heated, the material goes through a chemical change that causes it to harden into its desired shape. The
temperature, amount of pressure, and length of time utilized during the process depends on the desired
outcome.
4.2.3 Extrusion
The process of extrusion is usually used to make products such as film, continuous sheeting, tubes,
profile shapes, rods, coat wire, filaments, cords, cables, flat tapes, yarn, monofilament and multifilament,
etc. In general, any extrusion machinery consists of mainline equipment (rotating screw of specific
design and configuration fitted inside a cylindrical barrel, attached with die specific to the product
being extruded) and downstream equipment as required for the type and specification of end product.
As with injection moulding, dry plastic material is placed into a hopper and fed into a long heating
chamber. At the end of the chamber, however, the material is forced out of a small opening or a die in the
shape of the desired finished product. As the plastic exits the die, it is placed on a conveyor belt where it
is allowed to cool. Blowers are sometimes used to aid in this process, or the product may be immersed
in water to help it cool.
4.2.4 Injection moulding
The main method used for processing plastic is injection moulding. With this process, the thermoplastic
is placed into a hopper. The hopper then feeds the plastic into a heated injection unit, where it is pushed
through a long chamber with a reciprocating screw. Here, it is softened and melted to a fluid state.
A nozzle is located at the end of the chamber. The fluid plastic is forced through the nozzle into a cold,
closed mould. The halves of the mould are held shut with a system of clamps. When the plastic is cooled,
they harden/polymerize to an infusible state, the halves open, and the finished product is ejected from
the press.
In the case of thermosets, the feeding unit is cooled and the mould is heated to achieve the requested
crosslinking.
Thermosetting materials usually are not processed with injection moulding because before they will
soften, they harden to an infusible state. If they are processed with injection moulding, they need to be
moved through the heating chamber quickly, so they do not set.
4.2.5 Reaction injection moulding (RIM)
Reaction injection moulding, or RIM, is one of the newer processes used in the plastics industry. It
differs from liquid casting in that the liquid components are mixed together in a chamber at a lower
temperature of only about room temperature to 60 °C before it is injected into a closed mould. Here,
an exothermic reaction occurs. As a result, RIM requires less energy than other injection moulding
systems. Reinforced RIM, or R-RIM, involves adding materials such as milled or chopped glass fibre in
the mixture in order to increase the stiffness.
4.2.6 Thermoforming
Thermoforming uses a plastic sheet, which is formed with the mould by applying heat and then air or
through mechanical assistance. By evacuating air in the space between the mould and the sheet the
method is called vacuum forming.
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4.2.7 Transfer moulding
Transfer moulding is generally used only for forming thermosetting plastics. It is similar to compression
moulding because the plastic is cured into an infusible state through pressure and heat. Unlike
compression moulding, however, transfer moulding involves heating the plastic to a point of plasticity
prior to being placed into the mould. The mould is then forced closed with a hydraulically operated
plunger.
Transfer moulding was initially developed as a method for moulding intricate products, such as those
with many metal inserts or with small, deep holes. This is because compression moulding sometimes
disturbed the position of the metal inserts and the holes of these types of products. With transfer
moulding, on the other hand, the liquefied plastic easily flows around the metal parts without causing
them to change position.
5 Brief overview of plastic waste management
5.1 Waste management
The solid waste management is a global issue affecting our environment and living organisms. The
global picture of solid waste management is very different in different parts of the world. It depends on
many factors and trends and behaviours, predominantly on the economic welfare of those responsible
to establish and organize a solid waste management system locally, but also on consumption, waste
generation, composition, collection and handling, and has direct effect on recycling and recovery
of plastic waste. Every decision from individuals and government about consumption and waste
management affects the daily life and cleanliness of communities. Reference [2] shows that, as countries
develop from low-income to middle-and high -income levels, their waste management situations also
evolve. Urban waste management costs more for local administration budget in low-income countries
(20 %) compare to middle-income (10 %) and high-income countries (4 %). At the same time, funding
is more difficult for low-income countries when they have to compete for funding with other priorities
such as clean water, health care and education.
This document is a product of studying different aspects from waste management, generation,
composition, collection, treatment, and disposal to include information on financing and costs,
institutional arrangements and policies, administrative and operational models, citizen engagement,
special waste and informal sector. It included 217 countries and 367 cities. The cities that participated
in the survey are listed in Annex B (see Table B.1). The countries are divided in 7 regions East Asia
and Pacific, Europa and Central Asia, Latin America and the Caribbean, the Middle East and North
Africa, South Asia, Sub-Saharan Africa and North America. Based on the volume of waste generated, its
composition and how it is managed, it is estimated that 1,6 billion tonnes of carbon dioxide equivalent
GHG were generated from solid waste treatment and disposal 2016 which is about 5 % of the global
emissions (see Reference [3]). Plastic waste is 12 % of global waste composition. Waste composition
various by income level and percentage of organic matter in waste decreases as income level rises as
shown in Table 2.
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Table 2 — Plastic waste percentage varies depending on countries income
Income Food and Glass Metal Paper and Plastic Wood Rubber and Other (%)
level green (%) (%) (%) cardboard (%) (%) (%) leather (%)
Low 56 1 2 7 6,4 < 1 < 1 27
income
Lower- 53 3 2 12,5 11 < 1 < 1 17
middle
income
Upper- 54 4 2 12 11 1 < 1 15
middle
income
High 32 5 6 25 13 4 4 11
income
[1]
Source: Geyer, Jambeck and Law
There are differences in composition of waste and changes in this composition with time for countries
with different in-come, e.g. the share of organic waste which reflects changes in consumption depending
on enhancement of in-come for the countries. Tables 3, 4 and 5 show the waste generation, plastics
waste generation, and treatment of solid waste by region.
Table 3 — Share of waste generation by region
Region Middle East Sub- Latin North South Europe and East Asia
and North Saharan America America Asia Central and
Africa Africa and the Asia Pacific
Caribbean
Percentage
of waste 6 9 11 14 17 20 23
generated [%]
[1]
Source: Geyer, Jambeck and Law
Table 4 — Share of plastic waste generation by region
Middle East Sub- Latin North South Europe and East Asia
and North Saharan America America Asia Central and
Region
Africa Africa and the Asia Pacific
Caribbean
Percentage of
plastics waste 12 8,6 12 12 8 11,5 12
[%]
[1]
Source: Geyer, Jambeck and Law
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Table 5 — Percentage of waste disposal and treatment by region
Middle East Sub- Latin North South Europe and East Asia
Region/
and North Saharan America America Asia Central and
Treatment
Africa Africa and the Asia Pacific
[%]
Caribbean
Recycling 9 6,6 4,5 33,3 5 20 9
Incineration < 1 < 1 < 1 12 < 1 17,8 24
Landfill 23 24 43,3 54 4 21,4 49
(controlled
and
unspecified)
Open dump 52,7 69 26,8 < 1 75 25,6 18
Other 14,3 < 1 24,4 < 1 15 15
...