From Industry 4.0 to Research 4.0

A Modular Approach for the Development of Continuous Filaments Based on Man-Made Cellulosic Fibers

By Steffen Müller-Probandt and José Canga Rodríguez

An accelerated growing demand for textile fibers demands a more proactive approach which includes implementing frameworks and technologies for recycling and a broad use of biobased materials as an alternative to conventional polymers. Research work in the field of biobased fibers is characterized by a high degree of adaptation needs, hence demanding an efficient, systematic and, in part, self-optimizing experimental working system, which must be intelligent in gathering data from the process and flexible in enabling its rearrangement. Research 4.0 is a modular approach for the development of a product from the idea to its practical implementation.

Meeting Industry Demands

The global demand of textile fibers has been almost doubled from approximately 60 to 110 million tonnes per year from 2000 to 2020 while the number of produced garments increased three times from approximately 50 billion to 150 billion. With cotton stagnating at 20 to 25 million tonnes, the main contribution to this growth is provided by man-made fibers like polyester. In the same period, the world’s population has increased by approximately 30% to reach almost 7.8 billion people.[1] The mismatch between both growth rates reflects an imbalance leading to the unsustainable situation which we are currently facing.

In 2015 only 1% of textile products were recycled at a global level as the result of the big challenges that the textile industry is facing in order to reach circularity.[2] The factors are manifold: undesired substances which are embedded in the yarns and cannot be recycled, the fact that many garments are made of mixed materials which are hard to separate, recycling costs being higher than the value of virgin materials, etc.

Technical textiles refer to textile materials primarily used for their technical performance and functional properties. They make roughly 35% of the total production of fibers worldwide.[3] The global yearly consumption of technical textiles was approximately 42 million tonnes in 2021 and is expected to reach no less than 67 million tonnes by 2032, thus experiencing an increase of roughly 60%. In monetary terms the technical textile market is estimated to reach 43% of global textile sales by 2032 [4], so that the size of this market size is projected to grow from $164.6 billion in 2020 to $222.4 billion by 2025, i.e., at a CAGR1 of 6.2% [5] .

Given the anticipated rapid increase in demand for textile fibers in the years to come, it is crucial to implement transformative sustainable consumption and production models and circular business technologies both in the garment and technical textile industries.

Recycling Technologies

The Ellen MacArthur Foundation defines recycling as the last value cycle after other measures (inner value cycles) to restore and regenerate value with the lowest environmental impact possible [2]: a) Maintain/repair b) Reuse as a product c) Reuse as a material d) Recycle

Users represent the keystone for closed loops based on their behavior towards usage, maintenance and repair of textile products expanding their lives to the maximum possible.

Technical textiles are commonly not feasible for reuse as they usually reach their end-of-life status based on damage rather than based on fashion as is the case for garments. Reuse of textiles can be done as products (preferred option) or as textile material. When the quality of the fabric is such that it is no longer suitable for reuse as a product or material, it should be recycled.

There are mainly four main recycling technologies defining the industrial processing of new fabrics [6]: a) Mechanical recycling resulting in fibers as the raw textile material is broken down in separate fibers which can be re-produced into new textile structures. b) Chemical recycling of cellulosebased textile products (e.g., cotton, viscose, etc.) which are dissolved and spun into new fibers. c) Thermo-mechanical recycling of synthetic polymers, where polymers are melted and chemically improved (if required) before being spun again. d) Chemical recycling of synthetic polymers that are broken down to their monomers. Monomers can be polymerized again into the original polymers.

According to the EU Strategy for Sustainable and Circular Textiles, longlived and recyclable textile products will be placed in European markets. These products will be made of recycled fibers to a great extent and free of hazardous components. The vision of the European

Commission is a thriving ecosystem for circular textiles supported by sufficient capacities for fiber-to-fiber recycling and feasible services for reuse and repair. [7]

Biobased Fibers for Recycled and Sustainable Textiles

As consumers are nowadays searching for more sustainable solutions that address key environmental issues related to the garments they wear, there is a growing trend towards sustainability in the textile industry at a global level. This new situation is building up pressure on textile brands by holding them accountable for their environmental impact in a way that consumers expect meaningful social and environmental goals (e.g., ambitious CSR2 and ESG3 KPI’s4) and a trustworthy implementation of a sustainable product stewardship. This paradigm shift involves both the implementation of recycling approaches and a broad use of biobased materials like MMCFs5 as an alternative to polymers like polyester and nylon. MMCFs, also known as regenerated cel- lulose fibers, are a group of fibers that are conventionally derived from wood, whereas other sources of cellulose are gaining importance nowadays (e.g., alternative plant resources, recycled agricultural waste, etc.).

A value-added hierarchical usage of biomass is a keystone in building a more environmentally friendly textile production. In the cascade utilization of resources proposed by the European Directive 2008/98/EC [8], cellulose-based fibers would be one of the many different products to be processed out of wood in future bioproducts mills. In order to make out of biobased fibers a real competitor to established polymers like polyester or nylon, both securing feedstocks and a further development of spinning technologies will be essential.

Multimode®:

A Research 4.0 Solution for Biobased Fiber Innovation

Research 4.0 is to be understood as the implementation of the principles of Indus-

Starting from thread run studies on coating facilities to complete pilot installations can be implemented efficiently also to your task with the DIENES MultiMode® system. DIENES try 4.0 to research facilities. VDMA6 has developed a toolbox in which the stages of development represent the path to the realization of an Industry 4.0 solution. [9]

Cellulosic fiber products pose a big technological challenge as growing demands on the varying quality of biobased (virgin or recycled) feedstock and the achievement of a consistent fiber performance require a continuous development and optimization of both technology and production parameters.

Therefore, the technology required for the development of biobased fibers for sustainable garments and technical textiles should be intelligent and able of organizing itself. The spinning line will be divided in modules, which become cyberphysical systems that network with each other. Ahrens tries to get to the bottom of this terminology and delimits the artificial intelligence of technology from the human-centered concept of intelligence. He puts it: “Against such a background, it does not matter if technology is artificially intelligent or not, but on the fact that it supports people in bringing their intelligence and autonomy to full effect.” [10]

Hence, the focus shall be on the needs of researchers developing new biobased fiber materials. The Research 4.0 solution will be supporting the research team under a human-centered approach to create a system that can operate autonomously and with the capacity of organizing itself. Either the starting point is technology which shall be equipped with social skills and characteristics such as in intelligence, autonomy and self-organization, or the human being is the starting point and the technology the one to be reshaped to better support people in bringing their capabilities and qualities to full effect. [10]

Research work in the field of cellulosic fibers is characterized by a high degree of adaptation needs. Research facilities must be able to be adapted after initial experiments and the knowledge gained thereby. The necessary adjustments are made under the conditions of a highly complex manufacturing process, which is determined by many influencing parameters. This results in the following requirements for the flexibility of the electronics control of the research facilities: a) Integration: Easy integration of new production modules. b) Scalability: Easy replacement of production modules with modified specifications. c) Flexibility: Easy modification of production steps’ positioning within the production line. d) High Performance: Intelligent production modules synchronized by a master process control level. e) Analytics: Continuous monitoring and evaluation of process parameters.

A reliable development of textile and technical filament yarns demands an efficient, systematic and, in part, self-optimizing experimental working system, which must be intelligent in gathering data from the process and flexible in en- abling the rearrangement of the process. DIENES’s approach to meet such demands is called MultiMode®.

In a MultiMode® plant, each process step is represented by a module which can be individually adapted to customerspecific requirements and has its own decentralized control. Thus, a modular production line consists of several intelligent units which can be easily exchanged and rearranged at any time with a reduced programming effort. Moreover, all production parameters can be permanently visualized and recorded, enabling a complete traceability of the process.

DIENES supports its customers in the development of innovative sustainable products like precursor yarns for carbon fibers made from biobased raw materials offering a modular approach for the development of a new product from the idea to its practical implementation covering all stages of the complete validation process from the first lab trials up to an industrial scale production line: Principle Process Product Production.

The configuration of a MultiMode® system follows a hierarchical structure running at three levels: Slave (Level 1MMS: MultiMode® Slave), Master (Level 2 - MMM: MultiMode® Master) and Upper control (Level 3 - MME: MultiMode® Explorer).

Every single yarn treatment module represents a production step and can store knowledge at module level and act according to the function of the module in interaction with other modules. Each of these modules is equipped with a MultiMode® switch and control cabinet, hence it is equipped with its own intelligence based on a PLC to control itself and to organize the module in association with other modules in the plant. The control hierarchy has an intelligent modular structure that configures itself according to the arrangement of modules given by the hardware and the interfaces within the system. Thus, a structure is realized that allows new arrangements by configuration and without any programming work required.

From a control perspective, the process level with the MultiMode® boxes forms the control level “BASIC” with the MMS modules. Up to 14 of these basic modules can be switched to one MMM. This second control level “INTEGRATED” is organized by the MMM, which is also responsible for configuring and forwarding the information to the computerbased MME.

High requirements for a flexible control system and expectations regarding ergonomics are met at this level of integration: a) Easy extension or reorganization of the modules in the line. b) Different configurations of modules can be tested in a short period of time. c) Individual modules can be operated as standalone machines outside the line. The computer level control (MME) can be connected with four MMMs, that gives the possibility of 56 MMS modules connected to their corresponding MMM

Steffen Müller-Probandt, born in Frankfurt am Main in Germany studied Machine Construction and Economics graduated as Dipl.-Wirtsch.-Ing. TH-Darmstadt. Experienced manager in leading positions in Sales, Marketing and in Research and Development followed by top management positions for several well-known companies in the sector of textile machines. Since 2003 owner and CEO of Dienes Apparatebau GmbH. Under his leadership the company has evolved into a leading manufacturer of modular laboratory, pilot, and production lines for high performance filament yarns. He can be reached at muellerprobandt@dienes.net.

References

with their own local input displays or to an industrial PC via gateways allowing all visualization and control options by means of a touch screen as acting as HMI.

The upper control level is the process control level “ADVANCED” and organizes the elegance functions of the system like, e.g., real-time evaluation of sensors, data logging with a connection to an SQL database every second, tracking of operator inputs, transfer of data to Excel for further evaluation, alarm logging, recipe management for saving current settings as a recipe under a freely assignable name to be used a later moment if necessary, etc.

1 Compound Annual Growth Rate

2 Corporate Social Responsibility

3 Environmental Social Governance

4 Key Performance Indicators

5 Man-Made Cellulosic Fibres

6 Verband Deutscher Maschinen- und Anlagenbau (German Machinery and Equipment Manufacturers Association)

José Canga Rodríguez, born in Oviedo (Spain) in 1976, studied Chemical Engineering and is MSc in Environmentally Sustainable Process Technology. Over the last 17 years he has been working in different R&D, Engineering and Sales positions at companies delivering turn-key plants for paper making and recycling, industrial wastewater treatment and disposal of hazardous weaponised chemicals and ammunition. Since 2020 he is working as Head of Sales at Dienes Apparatebau GmbH providing modular spinning lines for innovative and sustainable filament yarns at lab, pilot, and production scale. He can be reached at j.canga@dienes.net.

1. Cordeiro et al.; Becoming mainstream: Future opportunities and challenges for novel textile; International Conference on Cellulose Fibres, Cologne, 2022

2. Ellen MacArthur Foundation; A new textiles economy: Redesigning fashion’s future, 2017

3. Market demand of technical textiles worldwide in 2014 and 2022 (in million tons). In Statista – The Statistics Portal, available at https://www.statista.com/statistics/741532/technical-textiles-global-market-demand/ (accessed on March 13th 2023)

4. Fact.MR (February 2022). Technical Textile Market.https://www.factmr.com/report/technical-textile-market (accessed on March 3rd 2023)

5. Markets and Markets (2021). Market Research Report (February 2021). https://www.marketsandmarkets.com/PressReleases/technical-textile.asp (accessed on March 3rd 2023).

6. Fontell, P., Heikkilä, P.; Model of circular business ecosystem for textiles, VTT Technical Research Centre of Finland Ltd, November 2017

7. European Union Strategy for Sustainable and Circular Texiles. European Commision, February 23rd 2022, https://eur-lex.europa.eu/ legal-content/EN/TXT/?uri=CELEX%3A52022DC0141 (accesed April 14th 2023)

8. European Commission; European Directive 2008/98/EC on Waste; Official Journal of the European Union L312/3, 2008

9. Stahl, Beate; et al; Leitfaden Industrie 4.0 Orientierungshilfe zur Einführung in den Mittel-stand; VDMA Forum Industrie 4.0; VDMA Verlag ISBN 978-3-8163-0677-1; 2015