PAPER RECYCLABILITY

Project Information

Grant agreement ID: E1

Start date 10 February 1994

End date 9 February 1998

Funded under

• European cooperation in the field of scientific and technical research (COST), 1971-

Total cost € 1 800 000,00

EU contribution No data

Coordinated by

Complutense University of Madrid
Spain

Objective

1.INTRODUCTION

Paper and board production is a major international industry and is important to the economics of most European countries whose total production in 1991 was 75 million tonnes. Paper and board is traded internationally with the balance of trade depending on the efficiency of production and the cost of raw materials. The principal raw materials, wood pulp and wastepaper, are also traded internationally. The selection of raw materials depends on the grade of paper and board to be produced, the availability of the material, its price and the manufacturing cost to convert it into the product. Recently the economic balance in Europe has favoured wastepaper with its use increasing in Europe from 33, 1% in 1987 of the total materials used to 36,2% in 1991.

Legislation will increase the availability of wastepaper by diverting it from landfill. Whether this wastepaper can be used for paper and board production will depend on the total economic and environmental costs of its collection, separation, grading and processing as a raw material. This is a complex topic, dependent on the treatment the wastepaper receives at all stages in the "paper chain" - original manufacture, coating, conversion, printing, end use, collection and separation and reuse. Up to and including the collection stages an increasing number of chemicals and other materials are added to ensure the functionality of the paper and board product or are introduced accidentally. .

Effective recycling depends on the ability to remove selectively and economically those materials that detrimentally affect the performance of paper and board products made from wastepaper; This task is made complex because these materials affect the performance of different products differently (e.g. residual ink is detrimental for a printing paper but not for the centre of a solid board).

In addition to the presence of contaminants, the papermaking and downstream processes change the properties of the fibres thus reducing their value as a raw material. Understanding at a basic level how these changes occur and their influence on the physical and surface chemical properties of the fibres is limited. An improvement in understanding would permit the development of reprocessing technology to reduce the impact of these changes on the cost of recycling and enable an increase in the levels of used paper being recycled.

There is also confusion arising from the use of environmental life cycle analysis to determine the relative merits of manufacturing products from new and recycled fibre. This arises from the different protocols, methodologies and average data for the various stages within the paper chain. A common approach would benefit the manufacturers in making decisions on the installation of appropriate process equipment and legislators in the development of targets for waste reduction and eco-labelling criteria. This would also assist in the objective assessment of the relative merits of incineration and recycling for a variety of used paper grades and populating densities.

Research is being undertaken on a number of aspects of paper and board recycling in various European countries in a disjointed manner with a variety of approaches which are sometimes in conflict being used. In contrast there is a major focus on recycling research within North America where effort is being co-ordinated. A concerted and co-ordinated research programme in Europe would help significantly to understand the basic factors which influence the recyclability of paper and board and thus improve Europe's ability to reuse wastepaper and minimize the effect on the environment.

2.ACTION OBJECTIVES

The aim of the Action is to improve the overall understanding at a basic level of the factors which influence fibre characteristics and fibre processing within paper and board manufacture. The Action will provide the platform for more applied studies which will be funded by industry or possibly by industry and the Community in the Framework Programme.

The objectives may be summarized as follows:

2.1.To characterize morphological and chemical changes that occur in and on fibres during recycling: the effects of these on their papermaking potential and investigate strategies to reduce or ameliorate these disadvantageous effects.

2.2.To determine the influences of chemicals added during various parts of the paper chain on process water quality and production efficiency in wastepaper using paper mills.

2.3.To increase basic understanding of the mechanisms of ink removal from paper surfaces in the de-inking process and the factors which control ink particle size distribution.

2.4.To identify opportunities for new technological approaches to reduce the influences of fibrous and non fibrous components of wastepaper on recyclability leading to better processes at all stages in the "paper chain".

2.5.To create a platform for the exchange of information on paper recycling and paper production models with the purpose of developing a common approach to life cycle analysis methodology and use.

2.6.To encourage the co-operation of precompetitive research and development on the subjects of recyclability and wastepaper processing at a European level.

3. PROGRAMME

The Action will be divided into four separate projects dealing with the technical aspects required to meet the action objectives and a working group on modelling and life cycle analysis. There will also be a project which concentrates on the dissemination aspect of the work. The objectives and broad technical contents of each project are described in 3.1 (3.1.1 to 3.1.4) the Working Group function in 3.2 and information dissemination in 3.3. The way in which the projects inter-relate is described in 3.4.

3.1.Technical programme

3.1.1.Fibre and fire surface characterization - project 1

Paper and board are essentially a matrix of cellulose fibres held together by hydrogen bonds. The properties of paper and board are dependent on the strength of the fibres, their physical characteristics (length, diameter, aspect ratio) and their ability to form bonds. This latter aspect is controlled by the surface characteristics of the fibre. All these important properties of fibres are altered at various stages in the paper chain. The extent to which the changes take place, particularly when chemicals are added is not well enough known but is critically important to the use of wastepaper.

The objective of this project is to assess how these properties change with each step in the "paper chain" and when paper is subjected to multiple recycling. The results will provide information to determine the limits of the number of times a fibre can be recycled and to the setting of realistic targets for wastepaper recovery and utilization.

Subjects which need to be investigated include:

*the identification and development of analytical methods;

*the planning for the use of these techniques for selected paper grades;

*the application of the techniques to various stages in the "paper chain" with concentration on chemical additives introduced during papermaking, coating, converting, printing (both conventional and non impact);

*the assessment of the effect of ageing of fibres;

*the influence of wastepaper treatment processes (e.g. dispersing, bleaching and de-inking) on fibre and fibre surface.

3.1.2.The basics of de-inking - project 2

To increase the amount of used paper recycled it will be important to incorporate it into higher standard products used for office and publication purposes. Critical properties of these products are brightness, shade and freedom from specks. These are achieved by a complex industrial process designed to remove ink from the paper. Essentially chemicals and energy are used to separate the ink from the fibres and subsequent stages exploit physical and surface chemical differences between the fibres and ink particles to effect separation. The control of ink particle size distribution and surface chemistry are critical to the efficiency of the de-inking process. De-inking has developed empirically and is not efficient - typically 60%-80% of the ink is removed and overall yields are in the range 75-90%. The low yield leads to solid residues and aqueous effluents which have to be disposed of.

The objective of this project is to assess how chemical conditions and applied energy influence the ink particle size distribution for a number of the more common ink/paper combinations. The results will provide information to determine how to add chemicals and apply energy within a de-inking system more efficiently. It will also lead to an insight on how ink manufacturers could modify their formulations to improve the de-inkability of the printed products.

Subjects which need to be investigated include:

- the development of analytical methods to characterize dried ink properties - cohesion, adhesion to paper surfaces, "dispersibility";

- the derivation and use of methods to determine the relative rates of fibre/fibre and fibre (paper surface)/ink separation;

- the derivation and use of methods to determine the effect of energy (intensity of application, overall level) on ink particle size distribution;

- the application of analytical methods to determine the factors which influence ink redeposition on fibres and the rate of deposition;

- the development of alternative chemical regimes and chemical application strategies to de-inking.

3.1.3.Soluble material identification and quantification - project 3

The presence of chemicals which are soluble in the process waters of paper and board mills may be the factor which limit the economic and environmentally acceptable recycling of wastepaper. These chemicals reduce yield and process efficiency. They also contribute to the cost of on-line treatment of effluent.

The objectives of this project are to identify and quantify the material which is potentially soluble and assess its effect on process efficiency and the level of effluent discharge. The information will be used to identify possible options which will reduce the environmental impact of recycling and those of the whole "paper chain". This will provide a platform for the development of process additives which will have reduced environmental impact and could contribute positively to recycling. An example of this is an additive which is substantive to the fibre and functions as a strength aid by reinforcing inter fibre bonding.

Subjects which need to be investigated include:

- the identification and development of analytical methods;

- the measurement of the trace soluble materials in wastepapers and mill systems;

- the identification of the source of soluble materials which impact adversely on the ability to recycle wastepaper and are potentially hazardous to the environment;

- the kinetics of dissolution and degradation of soluble materials;

- the formulation of a method to determine alternative options for additives to be used in various parts of the "paper chain";

- the identification of the ultimate fate of chemicals added to during paper manufacture and use.

3.1.4.Identification and study of new technologies - project 4

The paper and board industry has continually developed its processes to cope with the challenges arising from the introduction of new materials and newer downstream processes. In the case of wastepaper as new chemicals and substances are introduced into the "paper chain", incremental development in wastepaper processing equipment takes place. To these traditional challenges there will be added a new dimension of a poorer standard of wastepaper containing a greater proportion of previously recycled fibres. This wastepaper will be more heterogeneous and be more contaminated than the grades used now. However it must be processed into a product with the same properties in order to gain market acceptance and meet the same criteria as far as environmental discharges are concerned. The traditional development process may not be sufficient to cope with the future requirements to recycle more paper products and reduce the discharges from paper manufacture. Newer technologies e.g. based on biotechnology to eliminate the dissolved chemicals which are detrimental to paper recyclability and separation and fractionation techniques to enhance fibre quality will be required.

The objective of this project will be to identify suitable techniques and undertake feasibility studies at a laboratory stage.

The methodology used will be to identify potential technologies for various applications within the wastepaper processing and on-line effluent treatment stages by undertaking feasibility studies and possibly laboratory experiments.

3.2.Environmental Life Cycle Analysis Methodology Working Group

The paper and board industry is concerned to reduce its overall impact on the environment and has introduced a number of process improvements which reduce energy consumption, increase yield and result in "light-weighted" products, etc. The future direction the industry takes is difficult to define because of the complexities of the processes and the array of possible raw materials, which could be used. Proponents of a particular raw material and process use techniques such as environmental life cycle analysis to support their case. These claims can be disputed because there is no standard agreement on the methodology or the data, which are used. This leads to confusion inside the industry, amongst the industry's customers and in the minds of legislators.

Another problem faced by users of life cycle analysis is that their conclusions are based on existing industry practice and are invariably historic perceptions. Knowledge of newer processes and technologies is not fed into the models used. The models are used rarely to assist in evaluating and developing new technologies. It is thus important that closer links are forged between researchers and life cycle analysis practitioners.

This situation is capable of resolution by pooling knowledge amongst the groups which use life cycle analysis to determine the relative environmental merits of processes and products. A working group made up of leading and respected institutes will be set up as part of this COST Action to link life cycle analysis work with that of researchers.

The object of this working group will be to develop a common approach to undertaking environmental life cycle analysis and to reporting the results of such analysis.

It is envisaged that this group will tackle issues such as the use of standard data, the handling of energy consumption in pulping, the environmental "score" of wastepaper.

The work of the group will be publicised to improve the general industrial awareness of the utility of the technique, its strengths and weaknesses and scope of application.

3.3.Information dissemination

A vital part of the Action is the dissemination of the results to those within the "paper chain". It is envisaged that a number of activities will take place including:

*workshops on various technical aspects of the project at project level involving those who are actively researching and others with a contribution to play;

*seminars describing the work programme and the results which will be achieved;

*conferences on the subject of recycling;

*publications based on the results from the Action.

3.4.Action organization

A minimum of five partners for both the technical programme and working group are required. The partners will appoint a project co-ordinator who will be responsible for co-ordinating activities and ensuring that the Action direction will meet the overall objectives. Project leaders will also be appointed for each project within the technical programme and the working group. The project leaders will assist the Action co-ordinator and take specific responsibility for ensuring that the work is of a high standard.

Tasks within the Action will be assigned to the participants. Each participant will then appoint a task leader who will draw up a task plan and manage the work in line with the plan.

The Action co-ordinator and project leaders will form a steering group which will meet every six months to review progress and take remedial action if required. There will also be an annual meeting of all partners to which representatives of industrial companies will be invited.

Reports will be issued at the completion of each individual task and at the completion of projects. A summary report of the Action will be prepared at the end of this four year project.

4.MILESTONES

The Action is ambitious and is unlikely to be completed successfully in less than four years after the start of work. The milestones and the way the projects inter-relate are shown in Table 2 and Figure 2 respectively.

At this stage in the Action development the milestones are indicative of the progress anticipated.

Current status

To reach the objectives five Working Groups were established, each tackling one of the sub-objectives :

WG1 : Fibres properties
The expected achievements are :

- to provide information to determine the limits to the number of times a fibre can be recycled;

- to assess the influence of chemicals on recycled fibre properties;

- to set realistic targets for wastepaper recovery and utilisation.

This group acts as a forum to share the information on the progress of projects going on at the laboratories of the different participants. In order to facilitate comparison of results a lab-scale recycling procedure, the type of pulps to be used and different analytical methods have been defined.

WG2 : Fundamentals of de-inking
The expected achievements are :

- to model the de-inking process;

- to determine how to add chemicals and apply energy within a de-inking system more efficiently;

- to asses how ink manufacturers could modify their formulations to improve the de-inkability of the printed products.

Two meetings are organised per year : a working group meeting (WGM) to exchange and discuss current research results of the participants, and a workshop to give insight into a specific de-inking topic together with representatives from other institutes (not members of COST) and from the industry.

WG3 : Stock Preparation Chemistry
Dissolved and Colloidal Material (DCM) works on :

- methods to characterise the DCM present in the process water of paper mills and to determine the deposition capability;

- identification and quantification of the DCM that negatively affects the wet-end chemistry, the product quality and the water clarification process;

- identification of possible options which will reduce the environmental impact of recycling and those of the "whole chain";

- the basis for the development of new process additives which will have reduced environmental impact.

The WGMs are organised to share information about the subjects of the program and to define research needs or lacks in the programme in order to carry out an specific research. The dissemination of the activities is carried out through Workshops, organised in combination to WGM, which proceedings are published.

WG4 : New Technologies
The overall purpose of this Group was to determine whether the use of enzymes could assist in improving the economic performance of papermaking. Once the possible applications were identify and defined, the activities of this group were incorporated into WG2 and WG3.

WG5 : Life Cycle Analysis
The aim is to create a platform for the exchange of information on paper recycling and paper production models with the purpose of developing a common approach to live cycle analysis methodology and use. This work will illustrate different methods through examples and will validate methodological choices and give recommendations on when a certain method can be used. The work is based on case studies. A proper name for the method is "match racing", a parallel approach, when different methods are used on the same case, as a basis for discussion and evaluation of differences in the result.

The complexity of the total project has made it necessary to split it into three different phases :

I.- Cradle-to-grave inventory analysis of solid bleached board produced from virgin fibres.

II.- Life-cycle inventory analysis of solid bleached board, including recycling.

III.- Impact assessment.

Contacts have been made with industry bodies involved in paper and board sector.

Programme(s)

• IC-COST - European cooperation in the field of scientific and technical research (COST), 1971-

Topic(s)

• 14 - Forestry

Call for proposal

Data not available

Funding Scheme

Data not available

Coordinator

Complutense University of Madrid

• EU contribution: No data
• Address: 28040 Madrid ; Spain
• Total cost: No data

Participants (1)

Paper Research Institute Ltd.

Hungary

• EU contribution: No data
• Address: Duna u. 57 ; 1525 Budapest
• Total cost: No data