avoiding wastes and emissions in industry: experiences from austria

Avoiding wastes and emissions in industry: experiences from Austria

J o h a n n e s F r e s n e r

Stenum GmbH, Sparbersbachgasse 22, A-8010 Graz, Austria

Received December 1993: revised 6 April 1994

Over the last two years Stenum GmbH has conducted projects to minimize industrial waste and emissions at source, working with several companies involved in textiles, machine building, circuit board manufacturing, the automobile industry and the printing industry. This paper presents our experiences from recent projects with three companies, with about 200 employees each, from the textile and machine building industries within the Austrian PREPARE project, in cooperation with the Institute of Chemical Engineering, Graz University of Technology and the Institute for Ecological Economical Research (10W) in Vienna. The size and structure of these companies is typical of the Austrian industry. In all, the companies' hazardous waste could be reduced by at least 50%, and big savings arising from small technological or organizational changes could be realized. The reasons why these changes had not been found earlier were: lack of time on the part of staff; no systematic approach towards waste and emission problems; lack of information about which technologies are available in the market; and lack of clearly defined responsibilities for coping with environmental problems.

Keywords: was te ; emiss ions; indust ry

Options to reduce wastes at source

The main priorities in industrial waste management are: avoiding waste, recycling inside and outside the company, and finally treatment and disposal. Figure 1 shows a systematic representation of waste minimization options. In industrial processes, waste can be avoided by maintenance and good housekeeping.

Changing raw materials to avoid by-products or to eliminate toxic substances from the process is another possibility. Further options are changes in technologies to improve process control and to optimize operation. External recycling makes the wastes of one company the useful raw materials for other enterprises. If waste cannot be minimized in either way, it should fit into biogenic cycles to be recycled through geological

Approaches I

I Av°iding I Wastes and Emissions

| I I I

I°-'- I I - II-' the Spume Recycling Recyding I I

I I I

Raw Changing Housekeeping Ma~'ials Technologies

Figure 1 Classification of waste minimization options 2

0959-6526/94/01/0043-08 © 1994 Butterworth-Heinemann Ltd

I Utilizing Wastes and Emi~ons

I I

I I Biogenic Cycles

'1

Materials I

J. Cleaner Prod. 1994 Volume 2 Number 1 43

Avoiding wastes and emissions in industry: J. Fresner

structures, which means that the waste should not be toxic or a risk.

Waste minimization should be part of the design process of a product or process. Changes are easy in the conceptual phase of process design, whereas changing existing equipment always causes additional costs of replacing apparatus or in downtimes, risks and delays. At the same time, everyone involved in the production process has to believe in waste minimization: good housekeeping of chemicals, care of equipment, good maintenance to avoid leaks and spills and the steady supervision of processes to find deviations from the desired conditions, especially in small or medium-sized enterprises, are mostly up to the operators.

These options have been known for a long time, so why are they not applied in every enterprise?

Systematic approach to waste minimization

Our experience with Austrian companies ~-5 shows that environmental protection in industry is widely considered to be a matter of complying with limiting values for emissions prescribed by laws and regulations. Baas et al. 6 found that this is a widespread point of view in Europe. Waste minimization to reduce emissions below regulation requirements is not considered to be of interest. Why should we investigate where waste is generated and methods to avoid it? Costs associated with waste are usually insignificant in comparison to wages or the costs of raw materials. Where should we start, anyhow?

It is all a matter of a systematic approach: before we can eliminate waste, we have to know exactly how much there is and where it is generated. We also need motivation for the project. Costs are usually a good incentive: waste costs a lot more than the disposal fees; it has been purchased as raw materials and it has been taken through (part of) the production process. The aim is to increase the efficiency of processes in order to make the products out of less input materials; this is achieved by tracing emissions and waste back to their sources in the processes and by reducing them or avoiding them completely. It makes sense to look at environmental protection from a strategic view: analysing processes will increase the opportunities to improve their economy and there may be true innovations, thus it will improve competi- tiveness in future markets. Areas of future conflicts with environmental laws will be identified and eliminated, before it is necessary to add end-of-pipe technology to control emission problems. The fact that ecology and economy go together was proved, for example, within the project PRISMA in the Netherlands and the Landskrona project in Sweden.

Laborious academic work is not necessary, but systematic, clear, robust ways are needed to get a quick overview of the problem and then define the weak points and eliminate them. The real costs of waste need to be shown, and a system is required that

will trace the materials through the processes and provide a systematic and sufficiently global approach to avoid single measures (e.g. to comply with one regulation) without taking the whole business into account. To locate the exact amount, the source and the reason for wastes and emissions, the following methodology was used.

The method (Figure 2) is based on three foundations: teamwork (within the companies and between the companies and the consultants); a systematic approach; and balancing matter and energy at different levels. Environmental protection involves all divisions of an enterprise including purchasing, storing, accounting, data processing, production, waste logistics and marketing. Pollution prevention programmes need both strong management support and employee motivation. Teamwork within the company guarantees that all relevant divisions take part in the project, pool their knowledge, apply their individual know-how to other areas, develop creativity, and together support the solutions. The quick and comprehensive communi- cation of problems and potential solutions is crucial to the success of a waste minimization project. It depends on the involvement and the commitment of the team. Nevertheless, a project manager has to be responsible for the schedule and the documentation of the project.

Large companies often choose the project manager from their own organization. Many smaller companies rely on external consultants to organize such a project, especially for the first time. They rely on the consultants' experience in organizing such a project, their knowledge in locating the problems, their ability to communicate the problems, to initiate creative ideas and get professionals to consider solutions as soon as the problems are defined. External consultants are not blinded by routine, because they will look at the processes differently from the operating personnel who may have run the same process for years. However, consultants cannot be successful without the input of the people involved in the enterprise, who know the processes best and have to supply data and test the options to generate less wastes. A question of trust is the transfer of knowhow that is commonly associated with the work of consultants.

The pattern of the project organization follows the principle: first get an overview and then define and eliminate the weak points, whether they have technical, informal or organizational causes. It resembles in many aspects the method recommended by the EPA 8. At the beginning of a waste minimization project the team is formed within the company. A quick overview of the inputs and outputs of the company is collected and known problems are described. The aim of the project is defined. It is a good idea to define quantitative aims, e.g. to reduce toxic wastes by 30%, to eliminate all carcinogenic substances, to use 50% less water.

Next comes an analytical step, the aim of which is to make all material and energy flows through the

44 J. Cleaner Prod. 1994 Volume 2 Number 1

Figure 2

I Project organization

IAnalysis of input and 1 output of processes J

1 , Definition of problems J

I Collection of waste 1 and mission

prevention options

I_.o,o.o. 1 Selection of viable ] solutions

of solutions

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, Feedback of success J

I,--.n--o. o, --"- 1 Flow chart of a waste minimization project

company transparent (Figure 3). The basic logic is quite simple: what goes into a process has to leave it, either as a product, a by-product or an emission. Otherwise there is a material sink or source in the

Avoiding wastes and emissions in industry: ,J. Fresner

Input mt

Waste and Emissions

Figure 3 Looking inside the black box

process. Experience shows that this step can be of fundamental importance. In a brand new plant after only two years of operation (and continuous changes to increase production), the exact flows of water and waste water were only partially known. Two years and some undocumented changes were enough to result in no means of control over waste water quantities.

First, a mass and energy balance for the whole enterprise is made, so that the inputs to the company and the outputs (products, wastes and emissions) are determined (Figure 4). First qualitatively, then in terms of masses and prices, the necessary data for inputs, products and wastes are extracted from the accounting system. If this can be done with the available software, it will be a quick and yet comprehensive exercise. Collecting data for water, air and emissions can be quite difficult. If no measured values are accessible, measurements or estimations must be made. We allowed six months for balancing the input and output of the companies as a whole in the projects.

Walking through the factory itself, one will gain an overview of the processes and plants; one can structure the process and collect data on the flows of materials and energy among the process units. By matching these data to those from analysing the accounting system, a lot can be learnt about losses and good housekeeping. Raw materials are usually cared for very well. However, it can be a hard job to find out where the solvents, cleaning agents or lubricants go.

The weak points are then defined. Undoubtedly, violation of legal constraints is a weak point, as this may endanger the duration of the business. High costs are also weak points. The use of toxically problematic and especially carcinogenic materials is a weak point. There has to be a ranking of these criteria first and then an assessment of the inputs and outputs of the company according to these criteria.

In the next steps of the project, these weak points will be eliminated as far as possible. Not all existing problems will be eliminated in one project, so waste minimization has to be an on-going process. The main point is to understand more of the reasons for emissions and wastes and to eliminate them as close to the



Process Level AUxlII,

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Figure 4 Two-step analysis of a process

source as possible. So waste minimization has to become part of the corporate culture, with a management information system as an organizational back- bone.

Following the path of the streams, the wastes and emissions are traced back to the source in the process. Now matter and energy balances are applied to process units to determine efficiencies for materials' and energy usage. Compositions of the material flows will be analysed to keep track of valuable or undesirable components. The material and energy flows will be compared to design values, and values from similar plants, if available. The true costs of the wastes will be determined during these procedures, as the path of a material or a compound through the enterprise becomes clear from purchasing and storing, to using and treating the waste. The cost of purchasing and the value added through the production process will far surpass the cost of disposal for many waste streams.

Thus an efficient instrument for controlling the use of materials and energy is created during the process of collecting and compiling the necessary information. The desired degree of accuracy should be defined before going into all the details, otherwise the data collection will become time-consuming and frustrating.

In the second phase of the project, options for solutions are worked out and the economically favour- able ones are implemented; six months was allowed for this phase. Many options will include state-of-the- art techniques, which have to be adopted or optimized. Examining solutions from other industries will be useful, especially mechanical separation options. The main point is that one must use creativity and freedom to question the processes and operations. We have to find out the functions of the processes and how they work today, and we have to optimize the enterprise as a whole, not a single process step. The situation can be compared to Figure 5: it is like taking a piece out of the puzzle and finding another piece that fits into the enterprise without the wastes and emissions of the old one.

The creative phase of defining options has to be

separated from the phase of evaluating the options. This follows from the rules of brainstorming to avoid early criticism and the 'killing' of ideas hastily. Solutions will include the diffusion of options that are state- of-the-art, to elaborate research and development projects. They will not necessarily be technical solutions, but will include changing production procedures or improving information flow.

Economical assessment of the solutions and taking decisions on their implementation and investments are the next steps. The implementation and monitoring of the success of the solutions brings a good project to its end.

Solutions will result from the options of Figure 1. Good housekeeping (eliminating leaks in pipes, flanges, valves, covering open tanks, avoiding spills) will help to avoid the wastes. Switching to cleaner or different raw materials can eliminate undesirable by-products. Changing process conditions (temperature, pressure, ratio of inputs, concentrations, humidity) can optimize the use of materials. More efficient quality control will result from documenting material usage and process conditions. Materials, especially water or solvents, can be reused in the process. It can turn out to be economical to clean water (by ultrafiltration, for example), to recycle the water and to dispose only of the residues. Some other industry may be able to use the spent chemicals, such as solvents or acids; the Board of Trade, for example, may be able to help identify such a company.

Examples for waste minimization actions

The following paragraphs describe two examples of solutions from our latest projects. They also show how the problems were approached and solved.

Recycling solvents

A significant amount of solvents is used for cleaning gears in a textile mill; 90% of the solvents used are now recycled. Before the project, the amount of


Avoiding wastes and emissions in industry: J. Fresher

v V

Figure 5 Solving emission problems is like solving a puzzle

solvents used and their purchase and disposal costs were unknown to the operators. To separate spent solvents from residues by distillation is a widely used process in chemical engineering. So, after a laboratory experiment had shown that the spent solvents could be cleaned sufficiently by simple distillation, a company was found that produced the necessary equipment. After a quick calculation had shown a payback period of 1.2 years, and a pilot test run with the actual solvent had been carried out, the distillation plant was bought and put into operation. It has worked without any problem since then. An interesting side effect was that after the operators had learned about the price and the value of the solvents, the quota of solvent collected after use rose significantly.

Optimizing the use of water

Twenty per cent of water usage of another textile mill could be avoided by studying the processes and optimizing the use of water through better process control, i.e. by comparing different batches and checking for the minimum water needed to get a certain result and then controlling the process for that parameter. Thirty per cent of the chemical oxygen demand (COD) of the waste-water of the same plant could be avoided, by keeping fibres and dust out of the water by vacuum cleaning the fabrics before washing them and removing fibres from the waste- water by a sieve. Additionally, operational sequences have been partially changed to avoid wastes by frequently changing finishing baths. The problem of the finishing baths will be addressed by automatically operated mixing systems.

The checklist in Table 1 gives an overview of the options for waste minimization sorted by areas of the company. The motivation of the employees is of crucial importance: the success of the project and the

efficiency of the defined measures depends on their commitment.

Lessons from the projects

The time-consuming collection of the data needed in documenting the flow of materials and energy has truly been a problem in enterprises with many different products, few staff and no adequate electronic data processing. But it is worth the effort. The data about consumption of materials and energy have become a controlling tool in most companies. The company leaders now know their processes better than before, and the work has stimulated innovations. Cooperation with the authorities has changed in some cases, and the companies can use the results of their work for improving their public image and marketing.

Ninety-nine options were found to reduce waste in the machine manufacturing company and the two textile mills. From them, 62 measures have been adopted and six research projects are evaluating other options. We have classified the measures by their nature, their degree of innovation and their profitabil- ity. Figure 6 shows the nature of the solutions.

The results resemble the Dutch results from PRISMA7: 28% of the measures were good housekeeping measures to avoid leaks and spills, activating unused control equipment, etc.; 25% were changes in raw materials to eliminate volatile compounds and increase the use of biogenic raw materials; 30% of the changes involved changes in technologies. The technological background of the changes showed that process changes usually involve better controls and automatic data collection. Internal recycling is done in most cases with the aid of ultrafiltration to clean water for reuse. Two-thirds of the solutions came from the same industry; two-thirds were suggested by the consultants.



Table 1 Checklists for waste and emission reduction

Motivation [ ] Provide for instructions, training and supervision [ ] Provide for an incentive system for waste reduction ideas [ ] Create responsibilities [ ] Provide for information about costs [ ] Keep records of materials and wastes and use them for improving management [ ] Include waste minimization goals into job profile [ ] Include waste minimization goals into the enterprise's policy

Energy [ ] Check pressurized air system for leaks [ ] Use superheat of compressors for warm water [ ] Use heat recovery with heat exchange [ ] Check boiler efficiency [ ] Check lighting efficiency

Waste/ogistics [ ] Analyse waste composition [ ] Select optimum container sizes [ ] Use containers with different colours for different fractions

! [ ] Empty barrels completely [ ] Analyse packing materials

! Mechanica/ workshops [ ] Use pressure cleaning [ ] Use CFC-free cleaning

[ ] Close water cycles [ ] Regenerate cutting emulsions [ ] Regenerate lubricating oils [ ] Check oversprayin coating [ ] Use HVLP or electrostatic guns in coating [ ] Use standard parts [ ] Improve quality control

TexU/e industry [ ] Analyse washing and use of water [ ] Analyse surplus dyeing and finishing baths [ ] Analyse heating and control of direct dryers [ ] Cascade water usage [ ] Use computerized dosage systems

Process engineering and operation [ ] Minimize leakage in pipes, pumps and valves [ ] Minimize evaporative losses [ ] Minimize cleaning losses [ ] Improve mixing [ ] Use selective catalysts [ ] Increase sizes of production runs [ ] Segregate water for reuse [ ] Reuse rinse water [ ] Use continuous processes [ ] Use countercurrent processes

Figure 7 gives the degree of innovation of the implemented actions: 76% were the diffusion of existing knowledge to the companies, 15% were classified as innovations; 9% stimulated research projects to investigate the feasibilities for further improvements, where there were no 'easy solutions' because of the complexity of the problems. Table 2 gives the aims, a short description and the expected duration of the research projects.

The projects show a need for a systems approach to the complex problems. The solutions will require the cooperation of suppliers of raw materials and equipment, producers and customers. At the same time the solutions require networking of information from different stages of the production process. Cleaner production is a process that takes time, as it involves organizational as well as technological changes 9. It is not enough for consultants to locate the technological


Avoiding wastes and emissions in industry: J. Fresher

Internalrecycling

External recycling 7%

,d housekeeping 28%

Change of technologies

3O%

of materials 25%

Figure 6 Nature of the waste minimization actions

Research projects 9%

Innovatio 15%

Figure 7 Degree of innovation

;ion /0

options; they also have to be effective catalysts in a process that changes attitudes and organization.

Figure 8 gives details on the economy of the waste minimization actions, excluding the research projects.

< 1 year 44%

legal reasons, safety, image

44%

Figure 8

> 2 years 2%

1 - 2 years 10%

Economy o f actions (wi thout research projects)

Almost half the actions had a payback of less than one year.

Conclusions and future actions

This paper has focused on three recent waste minimization projects. Scores of options for waste minimization were identified in two textile mills and in one machinery builder; numerous solutions have been implemented, saving hundreds of thousands of Austrian Schillings annually in every plant. The investments made within this project and the cost of the consultancy work together have a payback period of about two years. These data provide motivation in three ways: (a) for more and more companies to conduct similar projects; (b) for the authorities to sponsor such projects instead of applying new and more stringent pollution control reguiations; (c) for the continuation of refining methods and compiling knowledge to tackle sophisti- cated waste prevention problems.

Acknowledgements

Special thanks are due to: the team at Stenum--Dr Hans Schnitzer, Helmut Moshammer, Kurt Schauer,

Table 2 Description and aims of the research projects

Title Description

Expected duration (months) Aims

Optimization of the air-conditioning system in a textile mill

Optimization of washing process

Optimization of dyeing process

Minimization of stenter emissions

Optimization of product packaging

Optimization of fnal quality control of yarn

Automatic frequency control of blowers

Ultrafiltration and recycling of water in combination with substitution of sizes and optimization of existing equipment

Recycling of dyes in combination with substitution of dyes Improved control in combination with substitution of chemicals and optimization of equipment Substitution of the conventional product packing of cardboard, polystyrene and polyethylene Substitution of visual control of product quality

6

12

6

12

15% reduction of energy costs for air conditioning

75% reduction of water usage

30% reduction of consumption of dyes

Elimination of 'blue smog'; 15% reduction of energy consumption

Use of a single material for product packaging

Automatic control of product quality



Wilhelm Zapfel; the companies--Werner Erhardt, Borckenstein GmbH, spinning mill, Dr Horst Miiller, Rosendahl GmbH, cable coating machine manufac- turer, Max Unterweger, Kufner GmbH, inlet fabrics mill; the sponsors---Michael Paula, Federal Secretariate of Science Research, Andreas Tschulik, Federal Secret- ariate of Youth, Environment and Family, and the Innovation and Technology Funds (ITF).

References 1 de Larderei, J. and Pounder, D.L. 'Cleaner Production

Worldwide', UNEP, Paris, 1993 2 Heitzinger, P., Schnitzer, H., Nnssbaumer, M., Regatschnigg,

H., Thiel, W., Grabher, A., Heitzinger, M. and Novak,

K. '0koprofit', Institute of Chemical Engineering, Graz University of Technology, 1991

3 Sage, J. Thesis, Institute of Chemical Engineering, Graz University of Technology, 1993

4 Schnitzer, H. 'Handbuch der Abfall- und Emissionsvermei- dung', Institute of Chemical Engineering, Graz University of Technology, 1991

5 Schnitzer, H. 'Konzeption des PREPARE-Projektes in Oster- reich', VT-Newsletter 7, Institute of Chemical Engineering, Graz University of Technology, 1992

6 Baas, L.W., van der Belt, M., Huisingli, D. and Neumann, F. Eur. Water Pollut. Control 1992, 2(1), 10

7 Huisingh, D. and Baas, L.W. Eur. Water Pollut. Control 1991, 1(1), 24

8 'Facility Pollution Prevention Guide', Office of Solid Waste, US Environmental Protection Agency, Washington, DC, 1992

9 Boons, F. and Huisingh, D. Eur. Water Pollut. Control 1992, 2(6), 40


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