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HomeMy WebLinkAboutGORE SystemGORETM Cover System W.L. Gore & Associates GmbH Page 1 of 17 Solid Waste Treatment confidential 10.01.07 DOCUMENTATION FOR THE APPROVAL OF GORETM COVER SYSTEMS AS ENCLOSED COMPOSTING SYSTEMS GORE;GORETM COVER SYSTEM AND DESIGNS ARE TRADEMARKS OF W.L. GORE & ASSOCIATES © 2007, W.L. GORE & ASSOCIATES GMBH - COMPANY CONFIDENTIAL - GORETM Cover System W.L. Gore & Associates GmbH Page 2 of 17 Solid Waste Treatment confidential 10.01.07 DOCUMENTATION FOR THE APPROVAL OF THE GORETM COVER SYSTEMS AS ENCLOSED COMPOSTING SYSTEMS Contents: DEFINITIONS .............................................................................................................................................................3 COMPOSTING SYSTEM.......................................................................................................................................................3 ENCLOSED........................................................................................................................................................................3 FUNCTIONING PRINCIPLE ......................................................................................................................................4 THE GORETM COVER SYSTEM –A SINGLE-STAGE FUNCTIONAL UNIT........................................................................................5 GORETM COVER LAMINATE STRUCTURE:.............................................................................................................................6 THE GORE EPTFEMEMBRANE ........................................................................................................................................7 OBJECTIVES OF CLOSED COMPOSTING SYSTEMS .........................................................................................8 ODOR RETENTION...............................................................................................................................................................8 RETENTION OF AEROSOLS AND MICROORGANISMS...................................................................................................................10 DUST.............................................................................................................................................................................12 HYGIENE........................................................................................................................................................................12 SUMMARY:..............................................................................................................................................................15 ANNEX 1: CERTIFICATES OF THE HYGIENE TYPE VALIDATION SYSTEMwwwww..wwwwwwwww18 ANNEX 2: HUNGARIAN CERTIFICATE FOR gENCLOSED SYSTEMuwwwwwwwwwwwwwwwwww19 GORETM Cover System W.L. Gore & Associates GmbH Page 3 of 17 Solid Waste Treatment confidential 10.01.07 Bear in mind that the demand for genclosedu or gin-vesselu composting systems is increasing globally when determining the technical standards or legal requirements for composting and for individual approval of composting systems. This leads to the following question: which are the systems that can be considered as enclosed systems and how can an enclosed system be defined? The GORETM Cover System should be considered in detail in this document. DEFINITIONS COMPOSTING SYSTEM A composting system is a system comprising functionally related components for favoring the microbiological decomposition processes of organic materials under aerobic conditions. ENCLOSED This term has various definitions in technical literature: Definition 1: The term gEncapsulationu according to the composting handbook means: enclosing composting areas having a waste air treatment unit1 Definition 2: A system is considered to be enclosed when the materials does not have any contact with the environment as against an open system; exchange of energy is however possible2. Definition 3: gEnclosedu means a spatial separation of the system from its environment. It is accepted that the term genclosed systemu must be modified for composting systems as these are normally in contact with the environment as far as materials and energy are concerned. In order to adhere to the aerobic composting process, the gases (C02,steam) generated by the microorganisms continually need to be replaced by atmospheric oxygen. Irrespective of the waste air treatment system, waste air is constantly released in the environment. 1 Composting handbook of the Bernkastel-Wittlich district administration, 2002 2 http://wasser-wissen.de/abwasserlexikon/g/geschlossenessystem.htm GORETM Cover System W.L. Gore & Associates GmbH Page 4 of 17 Solid Waste Treatment confidential 10.01.07 FUNCTIONING PRINCIPLE Conventional composting technologies normally use two-stage or multi-stage functional units to reduce emissions: gTwo-stage and multi-stage functional unitsu: Composting module (e.g. composting hall, composting tunnel) + biofilter or composting module + biofilter + washer gFunctional unit 1u: composting module: decomposition of biogenic materials, hygienization gFunctional unit 2u: waste gas collection and treatment plant: odor, aerosol and dust minimization Example As far as emission control is concerned, gFunctional unit 1u can be characterized as closed to a large extent when it is functioning properly. On the other hand, gFunctional unit 2u is intended for the essential exchange of materials with the environment and, among other things, also releases residual odor emissions in the environment. In comparison, the GORE TM Cover System achieves the same emission control with a single-stage structure. gSingle-stage functional unitu: (refer to pg. 5) Functional unit: Composting module including waste gas collection and treatment system: Optimization of the organic decomposition process along with reduction in emissions (odors, germs, dust, bioaerosols) INDOOR COMPOSTI NG 1 Enclosure suppression system 2 O2 measuring probe 3 Weather 4 CO2 5 Temperature profile measuring stick 6 GORETM Cover 7 Air 8 Heat 9 Odor 10 Moisture 11 Germs/bacteria F 1 F 2 GORETM Cover System W.L. Gore & Associates GmbH Page 5 of 17 Solid Waste Treatment confidential 10.01.07 THE GORETM COVER SYSTEM m A SINGLE-STAGE FUNCTIONAL UNIT The GORETM Cover system mainly consists of three components: GORETM Cover membrane enclosure, forced ventilation, control unit. The combination of the membrane enclosure and regulated forced aeration ensures safe process control. The ventilators are controlled by the oxygen parameter. The relevant data, which is taken directly from the heap body using sensors, is processed in the computer and is subsequently used for the documentation of the operational procedure. As soon as the mechanically pre-processed homogenized material has been placed on the aeration channels through front-end loaders and after the probes have been introduced in the composting material the GORETM Cover enclosure is pulled over the heap and sealed on the ground. The heap is not opened for the next four weeks. The membrane pore structure of the GORE TM Cover enclosure ensures a lot more than just the function of encapsulation m the treatment process is optimized. GORETM Cover System W.L. Gore & Associates GmbH Page 6 of 17 Solid Waste Treatment confidential 10.01.07 100% PES, highly tenacious, olive GORE ePTFE membrane 100% PES, highly tenacious, white The GORETM Cover laminate is also used in the BIODEGMA® system: GORETM COVER LAMINATE STRUCTURE: The GORETM Cover laminate consists of three layers firmly connected with each other: The core of the GORETM Cover laminate includes the Gore ePTFE membranes specially developed for the waste industry and manufactured using the GORE-TEX® membrane production technology. They are laminated between two high-tenacity polyester layers. On the one hand, they protect the composting material from seeping rainwater, and on the other hand, permit CO2 and water that develops during the composting process to escape. GORETM Cover System W.L. Gore & Associates GmbH Page 7 of 17 Solid Waste Treatment confidential 10.01.07 THE GORE ePTFE MEMBRANE The GORETM Cover membrane is made of three-dimensionally stretched Polytetrafluoroethylene (ePTFE). The pore size and even the air permeability, water-tightness, germ density and steam permeability are defined by this stretching process. For example: a drop of water has a diameter of approximately 0.1 to 3 mm and cannot seep through the pores; a steam molecule has a diameter of approximately 0.0003 µm and thus can easily seep through the membranes. A microscopic view of a GORETM Cover ePTFE membrane The GORE TM Cover laminate works against gaseous substances that escape from the composting material as diffusion barriers. A condensate film that retains odors and other gaseous substances also develops during the composting process on the inner side of enclosures made from it. These gases mostly dissolve in the water film and drip back into the composting material where the bacteria are further decomposed. This in turn reduces the overall emission flux. The correct choice of membranes also influences the moisture discharge during the composting process. On the one hand, it helps in preventing an excessively wet end product and on the other hand, the material contains sufficient moisture to enable adequate decomposition of biogenic materials, especially in arid zones. It is practically impossible for germs to pass through the Gore ePTFE membrane due to its microporous structure3. Germ reduction of > 99% could be proved in several microbiological tests: Industrial safety and safety of the residents is thus ensured. Thanks to the thermal insulation of the GORE TM Cover enclosure and the temperature-distributing excess pressure in the system, the temperature required for material hygienization can be ensured throughout the pit even during winter. Pathogenous germs throughout the composting material are definitely killed. As compared to a typical, structurally enclosed composting system with biofilter, only a maximum of a quarter or even less process air needs to be exchanged when the GORE TM Cover system is used. Emission fluxes and energy consumption are proportionately lower. 3 ANAWA Bioservice Scientific Laboratories GmbH, Report 951282 GORETM Cover System W.L. Gore & Associates GmbH Page 8 of 17 Solid Waste Treatment confidential 10.01.07 OBJECTIVES OF CLOSED COMPOSTING SYSTEMS Closed composting systems are required to meet the objective of protecting humans, animals, plants as well as water, soil and air from emissions such as odor, aerosols and dust. ODOR RETENTION Without any emission reduction measures, concentration of odorous substances within a range of 1,000 to 40,000 odor units per m³ waste air can be measured in composting systems. For the reduction of odors, odor concentration limit values or odor reduction rates are prescribed in technical norms or approvals from time to time. Both limiting values do not always lead to effective protection of the environment from odors. The limiting concentration ignores the odor flux decisive for the odor perception in the environment; the reduction rate does not consider the typical curve progression of odor formation during the composting process. However, whether and how frequently odors are sensed, and how disturbing these are found to be ghedonic toneu), is critical for the protection of the residents. The odor exposure guideline (GIRL (OEG)) applicable in Germany sets corresponding limiting values for the frequency with which odors can be perceived from a system in the nearest area. Residents should not sense odors for more than 10% (in residential and mixed areas) and 15% (in trade and industrial areas) of the total number of hours in a year4. Evaluation of the GORETM Cover System In the year 2000, the German Federal Foundation for Environment (DBU) supported a research project in cooperation with the University of Stuttgart and BIODEGMA GmbH, Stuttgart related to: gPrice-worthy composting under semipermeable enclosure covers compared to established aerobic waste treatment procedures?u5,6 4 Refer to GIRL m odor exposure guideline (OEG) 3.1, immission values, dated 21.09.2004 5 Refer to DBU 2000: Composting under semipermeable enclosure covering as a low-emission gLow-Techu and gLow-Costu process, final report of the research project AZ 08776, Osnarbrück, unpublished report; 6 Organic waste Composting, New developments and solutions for the reduction of odour emissions, HLUG, 2001 GORETM Cover System W.L. Gore & Associates GmbH Page 9 of 17 Solid Waste Treatment confidential 10.01.07 The comparison with other waste treatment procedures (container composting + biofilter, enclosed pile + biofilter) as described in the study shows that the procedure of enclosed cover composting shows excellent results as far as odor reduction is concerned. The study also illustrates that a two-week container composting with subsequent unventilated curing may lead to an absolutely disadvantageous emission situation even when compared to open windrow composting. This study also explains that the entire waste treatment system must be always taken into consideration when forming an emission balance; considering only a part of the system, such as only the high rate composting in an enclosed structure is not sufficient. This DBU research project revealed that the use of an enclosure cover with ventilation (heap A+B) in high rate composting as compared to open windrow composting (windrow C) leads to a 90% reduction in the odor emissions. If this enclosure cover is also used in the curing phase, the odor flux can be lowered to up to 98%. Windrow C: Open windrow composting Heap A+B: Composting with membrane covers Re-stacking: Re-stacking a heap Intensive decomposting: Phase I of intensive rot (high rate composting) Subsequent decomposition: Phase II of intensive rot (stabilization) Maturity: curing (Phase III) Decomposition age [d]: Number of composting days Odor load [OU/m²h]: Odor flux [OU/m²h] Meanwhile, after implementing more than 170 systems equipped with the GORETM Cover System across the world with a total throughput of 2.7 million tons per year, a lot of data from odor measurements is available from systems operated for years. They prove that odor emissions have decreased by more than 90% with the GORE TM Cover procedure7. 7 Cost-effective composting by using textile heap enclosures, pg. 181-190, M.Kühner, 1997; also refer to odor measurements in test heaps at the composting plant in Mannheim for the assessment of odor reduction using GORE-TEX® functional enclosures for heap composting, Stuttgart; unpublished report GORETM Cover System W.L. Gore & Associates GmbH Page 10 of 17 Solid Waste Treatment confidential 10.01.07 Based on these odor measurements, officially taken control measurements as well as on the aforementioned study, a comparative report about the odor immissions was prepared in 2006 by a qualified expert in accordance with the guidelines of the German Environmental Law (TA Luft, GIRL). This sample study confirms that the GORETM Cover System is at least equivalent to the established composting systems, and the GORETM Cover System achieves less odor immissions (odor perception frequencies) when compared with established tunnel or container composting systems. The minimum distances up to the nearest residential area as required by the German Approval Law can be reduced in system approval with the use of GORETM Cover System. To sum up, one may say that the GORETM Cover System has an odor reduction rate of up to 97%. Averaged over the entire composting period using the GORETM Cover enclosure (intensive rot), residual emissions less than 500 OU/m³ can be achieved. RETENTION OF AEROSOLS AND MICROORGANISMS Biotechnical procedures use and optimize biological decomposition processes that are then accelerated and optimized spatially. With these processes, bioaerosols (simplified in the following as gGermsu), i.e. air-borne bacteria (e.g. actinomycetes), fungi or their spores (aspergilla), as well as dead particles can be found in addition to the normal emissions such as dust, odor or noise. In order to prevent danger to or negative effects on system personnel and residents, extensive retention of these bioaerosols is essential from the point of view of immission control. Different types of germs have different sizes8: x Bacteria and spores: 0.5 m 10 µm x Fungus spores: 1 m 30 µm x Viruses: 0.02 m 0.26 µm Gore microporous ePTFE membranes are capable of effectively retaining germs of these sizes. This retention effect is supported by the fact that microorganisms do not normally appear as individual particles, but exist in the form of the described aerosols of microcolonies and aggregates linked to dust particles or water droplets 9; thus, they have cross sections that are considerably larger than the pore sizes of the Gore ePTFE membrane and can be therefore filtered more effectively. 8 Organic waste Composting m New developments and solutions for the reduction of odour emissions, page 7, HLUG, 2001 9 Organic waste Composting m New developments and solutions for the reduction of odour emissions, page 13, HLUG, 2001 GORETM Cover System W.L. Gore & Associates GmbH Page 11 of 17 Solid Waste Treatment confidential 10.01.07 Since the cost factors in the industrial waste management require the decomposition and stabilization of the organic material to be as fast as possible, even the microbial activity in the composting system should be increased. This also includes high germ concentrations within active composting systems10. Structurally enclosed systems retain aerosols by collecting waste air and by treating waste air loaded with germs using a two-stage or multi-stage functional unit (e.g.´scrubber-filter combination). Comparative measurements11,12 within and outside the GORETM Cover membrane enclosures show an almost 100% retention capacity as regards air-borne germs for the total number of bacteria (GBZ), the total number of molds (GSPZ) as well as for both the primary germs of these categories, namely Aspergillus Fumigatus (AF) and Thermophile Actinomycetes (TA). Refer to the following figure for composting under semipermeable laminate enclosures13. 10 Microorganisms in the environment of waste treatment systems, Hessian State Office for Environment and Geology, Department of Waste Management, Volker Kummer, Pg. 37-38 11 Microorganisms in the environment of waste treatment systems, Hessian State Office for Environment and Geology, Volker Kummer, Pg. 34 12 Refer to Fischer, K.& Kühner: Cost-effective composting by using textile pit lids, pg. 191-209 13 Refer to Organic waste Composting m New developments and solutions for the reduction of odour emissions, HLUG AF:Aspergillus Fumigatus TA: Thermophile Actinomycetes GBZ: total number of bacteria GSPZ: total number of molds GORETM Cover System W.L. Gore & Associates GmbH Page 12 of 17 Solid Waste Treatment confidential 10.01.07 The almost complete retention of every sort of germ is also confirmed by certificates 14 of independent testing institutes, which could prove the impermeability of the heap enclosure used in the GORETM Cover System with the help of enhanced testing devices. Measurements for the residual germ flux above the GORE TM Cover membrane enclosure show that emissions even during the high rate composting phase are reduced to germ-figures below the limit of detection15. DUST Dust is a natural element of air and thus exists virtually everywhere. Among other things, dust is formed by the release of biological materials (spores, seeds), and rises from the ground. Dust can be differentiated as coarse dust (> 10 µm) and fine dust. Dust with a particle size between 1 and 10 µm is termed as fine dust16. This fine dust is ubiquitous, can be inhaled and may affect the health. In the technical instructions for keeping the air clean (TA Luft), a limiting value of 10 mg/m³ is determined for dust-forming emissions in waste air (TA Luft 5.4.8.5: total dust). The GORETM Cover membrane has an average pore size of 0.3 µm. Empirical values prove that the GORETM Cover enclosure retains at least 99% of the fine dust. HYGIENE From the point of view of quality, gHygienic safetyu is an important criterion for the compost assessment. As per the requirements of the EU Law, waste treatment procedures must prove their epidemic and phytohygienic safety and their hygienic effectiveness, especially when waste of animal origin is being treated. For composting, this means that plant germs as well as germs that may be in the feedstock used for creating compost are definitely killed during the composting procedure used and during which high temperatures are generated. Moreover, a system must be designed such that re-contamination of the hygienized product is ruled out. This is achieved by encapsulating the heaps and a controlled collection of leachate, among other things. 14 ANAWA BIOSERVICE Scientific Laboratories GmbH, Report 951282 15 Refer to DBU 2000, pg. 142 16 Refer to www. Umweltlexikon: fine dust GORETM Cover System W.L. Gore & Associates GmbH Page 13 of 17 Solid Waste Treatment confidential 10.01.07 Type approval The hygiene type approval system is based on the principle of testing certain composting and fermentation procedures thoroughly for their efficacy to kill germs/effectiveness in killing germs. As one of the pioneers, the German Federal Community for Quality has created an extensive set of rules to determine the composting and fermentation procedures as hygienically tested prototypes17. Then, Salmonella senftenberg W775 (H2S negative), tomato seeds, Tobacco-Mosaic virus and Plasmodiophora brassicae must be removed from the biological waste, so as not to let the compost become a medium for spreading germs. This must be safely and reliably carried out in every single batch. In Germany, all composting systems must undergo a direct process inspection, i.e. the so-called hygiene type approval as per § 3 section 4 and annex 2 of the biological waste decree (BioAbfV) among other things18. The GORE TM Cover System (three layer laminate with ePTFE membrane and manipulator, forced air ventilation and oxygen-temperature-control) sold by W. L. Gore & Associates GmbH is one such approved type: In the gHeap encapsulatedu19 category, this technology has an independent type which proves that certain primary germs are reliably killed within two weeks even though they are, thermodynamically, at the most unfavorable positions in the heap body. The continuous monitoring and documentation of temperatures and oxygen concentrations in the individual pit batches using the operating software, the so-called indirect process inspection, ensures a cost-effective and permanent check of the composting process. By striking a balance with the necessary minimum requirements (correlation of time, temperature and particle size), the operation of the composting system as regards process hygiene can be achieved for each batch in conformity with the law. The type approval ensures that hygienic safety of the composting process is achieved with membrane- covered, forced air ventilated systems (GORE’ Cover System) just as in structurally enclosed systems. Also as far as hygienic safety is concerned, the GORETM Cover System is state-of-the-art. Similar testing criteria are also applied in the same or a similar form in other countries for the determination of hygienic suitability of composting systems. Even Hungary has implemented a similar certification procedure. The GORETM Cover System has been acknowledged as a closed system in Hungary as well.20 17 Refer to hygiene prototype test, 3rd revised edition of the Bundesgütegemeinschaft Kompost e.V. 18 Refer to the decree on the assessment of biological waste on soil used for agriculture, forest and gardening (biological waste decree m BioAbfV) dated 21.09.98 in BGBI I, pg. 2955ff 19 see annex 1: HB certificate, technical data sheet 20 Confirmation about the fulfillment of criteria of an genclosed compost systemu, Szent Istvan University, Gödöllö, 2002 GORETM Cover System W.L. Gore & Associates GmbH Page 14 of 17 Solid Waste Treatment confidential 10.01.07 European Animal By-products Regulation (ABPR; 1774/2002/EC) Implementation of the European ABPR guideline is very different as per the national law. There are still uncertainties in the implementation of the guideline; a uniform European procedure is lacking. Existing type approved systems are taken as a basis to test for the conformity to ABPR to a certain extent. In some cases, single and repeat tests must be conducted for systems. In any case, apart from fulfilling the technical requirements, organizational measures have to be taken to rule out the re-contamination of the hygienized product. An example could be the London Waste Composting Center in Londons Edmonton EcoPark that was approved in 2005, since Great Britain applies the most stringent standards in the whole of Europe as regards reactions to the BSE and foot-and-mouth disease. 30,000 t/a of kitchen, green and garden waste (140 t/day) from the seven London districts is treated there in 16 composting modules from BIODEGMA®: in order to fulfill the stringent ABPR requirements, these composting modules are always loaded from one side and emptied from the other. This is achieved by a proper separation of the necessary front-end loaders. The gTwo-Barrier-Systemu can be thus implemented to rule out the risk of re-contamination of the hygienized product: The material to be treated undergoes a three-week closed high rate composting and then a similar three-week enclosed stabilization; thus, hygienization is ensured twice. The fresh compost subsequently matures for another 4-6 weeks in unventilated windrows (turned with a side turner), before it is finally marketed as high-quality ready compost. Composting systems with GORETM Cover enclosures have been approved in many countries (Ireland, Hungary, Great Britain, Spain, and Germany) since the national ABPR laws have come into force. GORETM Cover System W.L. Gore & Associates GmbH Page 15 of 17 Solid Waste Treatment confidential 10.01.07 SUMMARY: The requirement for enclosed or in-vessel models of composting systems is justified for the protection of the health of humans, animals, plants and environmental assets, namely water, soil and air from emissions such as odor, aerosols and dust. The term genclosed systemu for composting systems of all kinds is only partially applicable as they are unexceptionally in contact with the environment as far as materials and energy are concerned. Irrespective of the waste air treatment system, purified waste air is always released in the environment. Composting systems with GORETM Cover enclosures have been internationally recognized as enclosed or in-vessel systems (e.g. in Hungary, USA, UK, Spain, Sweden, Italy, Ireland, Finland, Estonia, Germany and Canada). The GORETM Cover laminate is water-proof and reduces odor. As against open systems, it prevents convection. It is thermally insulating and germ-proof. The GORETM Cover System can be considered as a single-stage functional unit. At the same time, this system meets all requirements that are met by two or multi-stage functional units (retention of dust, odor and aerosols). It also meets the requirements of the hygiene type approval system and produces compost of the highest quality. The parity of the membrane-covered, forced ventilated GORETM Cover composting system as regards emission control led to the approval of more than 170 systems in 27 countries across the world. GORETM Cover System W.L. Gore & Associates GmbH Page 16 of 17 Solid Waste Treatment confidential 10.01.07 Annex 1: Certificate of the hygiene type approval conducted at the Cyriaxweimar composting plant GORETM Cover System W.L. Gore & Associates GmbH Page 17 of 17 Solid Waste Treatment confidential 10.01.07 Annex 3: Hungarian certificate for genclosed systemu SZENT ISTVÁN EGYETEM GÖDÖLLėI TERÜLETI IRODA TALAJTANI ÉS AGROKÉMIAI TANSZÉK DR. ALEXA LÁSZLÓ PhD. 2103 GÖDÖLLė PÁTER KÁROLY U. 1 TEL: 28/410-200/1811 FAX: 28/410-804 C O N F I R M A T I O N About the fulfillment of the criteria of an “enclosed composting system” According to the Hungarian environmental protection guidelines and legal norms (biological waste decree, 2002), a composting technique is recognized as an enclosed system, if “during the composting process, the raw materials are separately treated in a closed area, without letting the untreated solid, liquid or gaseous particles enter the environment.” “In closed systems, the composting process is accelerated by forced-ventilation, optimization of the water content and temperature.” In accordance with the aforementioned features, the GORETM Cover System, comprising the GORETM Cover, a ventilation unit and a control unit is recognized as an “enclosed composting system”. E X P L A N A T I O N The conformity with the environmental protection guidelines has been confirmed as per the logs of the laboratory tests conducted at W.L. GORE & ASSOCIATES GmbH, Pasteur Institute and Anawa Bioservice, and as per the practically oriented logs of test composting (see annex 1 and 2 of the claimant). The raw materials are spatially separated and treated by covering the heaps with GORETM cover, and by fastening the cover. This helps in preventing dust emissions and the scattering of different larger particles due to wind. The GORETM Cover System also helps in separating the accumulation and the backflow of leachate of endogenous origin during the composting process. In the claimant's composting system, ground water contamination is prevented by collecting this leachate in the leachate channels installed below the heaps first, and then in the tanks. The spreading of odorous substances and the molecules responsible for the odor emission is ascertained with the help of olfactometeric measurements and computer modeling. On the basis of these tests, it was proved that only a minimal quantity of odorous substances reach the environment with this technology, which is safe from the point of view of environmental protection as well as industrial safety. GödöllĘ, 15 April 2002. Dr. Alexa László