Helsinki mw

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Collaboration with UAF School of Management:
Associate professor Jim Collins, UAF School of Management Director of
Entrepreneurship, has taken an interest in this project and begun involving some of his
students in working on the economic feasibility and business-planning aspects. This
project provides students with an excellent opportunity to leverage their academic
study and exercises into real-world results. CCHRC is pleased and grateful to have the
opportunity to collaborate with these students and for Dr. Collins’ interest and
mentorship.
Collaboration with Small Businesses in Fairbanks & North Pole:
A growing number of local cement-related business owners and managers are
expressing interest in participating directly in CCHRC’s efforts to develop the commercial
applications of geopolymer cements and concretes. These businesses presently include
Stonecastle Masonry, Fairweather Masonry, MAPPA Test Lab, and Fairbanks Precast &
Rebar.
One of the top 20 in the 2010 Arctic Innovation Competition:
Out of more than 200 entries in the UAF School of Management 2010 Arctic Innovation
Competition, CCHRC’s presentation (given by Ty Keltner) on the potential for local
geopolymer development was selected as one of the top 20. The final four projects
were notably further along in the process of establishing a specific business. CCHRC’s
involvement in the competition helped establish connections with individuals
contributing suggestions and expressing interest in working with us in the future. These
included Jim Collins in the School of Management and Shiva Hullavarad in the Advanced
Materials Group of the UAF Institute of Northern Engineering.
Collection and organization of 2.5GB of relevant literature:
CCHRC staff have collected, organized and partially reviewed more than 2.5 GB of text
on the alternatives to portland cement. That currently amounts to 2,049 files in 161
folders and seven mind-maps, including over 600 research papers. Plus seven text books
on geopolymer cements. Although it is outside the scope of this project, the
organization of this information has been done in a manner which will facilitate
references, abstracts and CCHRC’s notes being made publically available on the Internet
without copyright infringement. It is our hope that this extensive and on-going literature

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Helsinki mw

  1. 1. M. Weil, E. Gasafi, A. Buchwald, K. Dombrowski: Sustainable Design of Geopolymers - Integration of Economic and Environmental Aspects in the Early Stages of Material Development. 11th Annual International Sustainable Development Research Conference, Helsinki, Finnland 2005
  2. 2. Sustainable Design of Geopolymers - Integration of Economic and Environmental Aspects in the Early Stages of Material Development Marcel Weil* Forschungszentrum Karlsruhe, Institute for Technical Chemistry, Department of Technology-Induced Material Flow, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany E-mail: marcel.weil@itc-zts.fzk.de *Corresponding author Edgar Gasafi Forschungszentrum Karlsruhe, Institute for Technical Chemistry, Department of Technology-Induced Material Flow, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany Anja Buchwald Bauhaus University Weimar, Chair of Building Chemistry, Coudraystr. 13, 99421 Weimar, Germany Katja Dombrowski Freiberg University of Mining and Technology, Institute for Ceramic, Glass, and Construction Materials, Agricolastr. 17, 09596 Freiberg, Germany Abstract Design of novel products is a complex, multi-level process. It may be divided into the two main phases of material and product development. Up to now, economic and ecological assessments have been carried out mainly after the development of materials. At that point of time, however, there is only a small degree of freedom to change the composition or process and to optimize the materials. The authors present a new systematical approach which considers economic and ecological aspects in the early phase of materials development, as shall be illustrated by the example of geopolymers (alkali-activated material). 1/14
  3. 3. In this approach, systems analysis tools like Multi-criteria Decision Analyses (MCDA), Life Cycle Assessment (LCA), and Life Cycle Costing (LCC) will be used with the aim of guiding the development of geopolymers in a sustainable way. The presented paper shall focus on the first of three steps of the approach, namely, the evaluation of the solid raw materials for geopolymer manufacturing. Keywords Systems analyses, Multi-criteria Decision Analyses, Life Cycle Costing, Material Flow Analyses, material development, composite materials, geopolymers, alkali- activated material, evaluation of raw materials, building products Biographical notes: Marcel Weil has been awarded a PhD in engineering by the Technical University of Darmstadt. His research interests and areas of experience include Life Cycle Assessment - especially of newly developed products and processes, Eco- Labeling, Material Flow Analyses, Life Cycle Thinking, and Systems Analyses. 1 Introduction The design phase of a product has to take into account different aspects for a successful product implementation. Early stage Material development Degree of freedom TP Information Product development TM [t] Late stage Product Figure 1: Degree of freedom for modifications of material combinations or the manufacturing process in the phase of material and product development 2/14
  4. 4. Economic considerations are always important to product development, but also environmental aspects have become an important issue in recent years. The environmental aspects will get even more attention in the future, if an environmental product declaration (EPD) will become obligatory for building products in the European Union (EU 2004). In contrast to this, the main focus of investigations of material development is on technical aspects like mechanical strength. If at all in material development, economic and ecological assessment are carried out after the technical investigations are finished (TM, Figure 1). More often, they are postponed to the subsequent phase of product development (TM-TP, Figure 1). This course of action has several drawbacks. If economic and ecological aspects are neglected during material development, they are not available in the early phase of product development, thus a selection can only be based on the technical properties of the materials. Two cases are conceivable: • For product development, some candidates with good technical properties are considered, which might have no chance of being implemented on the market due to their bad economic and/or ecologic performance. Consequently, time and money will be squandered. • If a less suitable economic and/or ecologic performance of a candidate becomes obvious during the phase of product development, there is only a small degree of freedom to change or to optimize the composition or the manufacturing process of the material without spending additional time and money for basic investigations. Therefore, a prospective development of materials should consider technical, but also economic and ecological aspects for a successful and efficient product development. But also for the material development itself, integration of economic and ecological aspect has advantages. As research projects are limited in time and money, a group or a selection of raw materials or a selection of raw material combinations is very often investigated for the technical properties only. A systematic investigation covering all sensible raw materials and mixtures would exceed the possibilities and capabilities of a normal project because of the high expenditure needed. 3/14
  5. 5. Only a screening which does not only consider technical aspects, but also economic and/or ecological aspects allows for an efficient and systematic material development that is initially based on all sensible materials and successively excludes the less promising materials from the further investigations. The level of screening has to be adjusted to the availability of information, the aim, and time span of the project. 2 Background Geopolymer Geopolymers consist of a silicate-aluminate solid component (binding material) and an alkaline liquid component (alkaline activator), see Figure 2. After simple mixing of both components, dissolution takes place, accompanied and followed by a polycondensation (Davidovits 1976). The formed polymeric network of alumosilicates (geopolymer binder) hardens in an amorphous to semi-crystalline structure. Depending on the amount of soluble calcium oxide in the raw materials, also mineral phases may occur, similar to the hydration products of portland cement (Buchwald et al. 2005a). In this respect, geopolymers represent a link between ordinary Portland Cement (OPC) and sodium silicate binders. Binder Geopolymer setting mixing Binding material: •metakaolin •slag •fly ash •activated clay •... Alkaline activator: •NaOH/KOH •sodium water glass •potassium water glass •... + water Figure 2: Production of the geopolymer Geopolymers have been investigated for more than 25 years. Despite these long- lasting and continuous investigations, geopolymers have not yet reached a wide application. In fact, a wide range of applications is described in literature, but only a few niche applications can be found on the market. 4/14
  6. 6. This is surprising, especially because geopolymers (in comparison to cement- based composite materials or ceramics) are reported to have many advantages: • Resistance against acids • Temperature resistance • High strength • High durability • Cold setting • Quick setting • Stable bonding of heavy metals and harmful substances • Simple manufacturing technique The favorable technical properties are proved by numerous investigations, e.g. (Bakharev 2005), (Fernandez-J. and Palomo 2003), (Bakharev and Sanjayan 2002), (Hermann et al. 1999). But they depend on the curing time and temperature and very strongly on the mixture composition of the chosen solid and liquid components. Ecological and economic features of geopolymers have hardly been investigated so far (e.g. in (Davidovits 2002)). But it can be assumed that they depend very strongly on the mixture composition, too. So far, metakaolin has been applied mainly as a solid component to produce high-performance geopolymers. However, thermally activated kaolin (metakaolin) is a relatively expensive raw material. Consequently, the application fields are restricted due to the costs. In contrast to this, relatively cheap industrial by-products or residues, such as blast furnace slag, fly ashes or sewage sludge ashes, can also be used as solid components. These activated solids, however, may be associated with some drawbacks regarding the technical performance, e.g. retarded setting or low mechanical strength. Furthermore, the geopolymer system is very sensitive to changes of the chemical composition. As the chemical variations of secondary raw materials generally are larger than those of natural raw materials, it is more difficult to reproduce such geopolymers with comparable properties. Hence, the application fields are restricted by the performance. 5/14
  7. 7. 3 Development of Geopolymers 3.1 Goals The overall goal of the work presented here is the selection and optimization of the most promising geopolymer compositions for specific fields of application. The pretension of this approach is to consider all sensible raw materials or material combinations and to investigate them in a systematic manner. A methodological approach has to be performed to reach the goals and to fulfill the pretension. 3.2 Systems Analysis Tools For this approach, a set of systems analysis tools or methods were selected: • LCA (Life Cycle Assessment, according DIN EN ISO 14040ff , 1997) to list the ecological advantages and disadvantages over a specific period and/or the whole life cycle of geopolymers compared to traditional materials or products. The LCA results will also be used for the optimizations of geopolymers. • LCC (Life Cycle Costing) to present the economic advantages and disadvantages over a specific period and/or the whole life cycle of geopolymers compared to traditional materials or products. The LCC results will also be used for the optimizations of geopolymers. • MFA (Material Flow Analyses) to answer questions regarding the availability of raw materials and to show the effects of different recycling scenarios of the materials compared • MCDA (Multi-criteria Decision Analyses) is used to select (screening) the more promising raw materials for geopolymers manufacturing and to identify the most promising geopolymers for specific applications. As a very high number of different properties have to be compared and balanced for the selection, MCDA has a very central position in this approach. 6/14
  8. 8. AHP (Analytical Hierarchic Process) shall be used to elicit the weights of attributes and objectives (technique, ecology/health, economy) and for the calculation of the aggregated score of each alternative. The results of AHP will be compared with the results of a dominance concept (Weber and Eisenführ 1993) which will be conducted in parallel, without any weighting of the objectives. This set of systems analysis tools or methods was selected for the development of geopolymers. However, these tools and methods could also be applied to other developments of materials. This does not means that no other or additional tools and methods are more suitable under specific circumstances (different initial situation). 3.3 Overview of the Approach The authors will present a methodological approach to integrating technical, economic, and ecological aspects in the early stages of material development. It is started from a broad variety of raw materials, which will be reduced (screening) step by step to a few promising material combinations (geopolymeric product) for specific applications (Figure 3). For a promising selection and optimization of the different candidates, screening with regard to technique, economy, and ecology has to be based on information on the application fields. Therefore, its is crucial to investigate the general conditions of the application fields and the final 3rd step (Figure 3) of the specific application. This means that also the market, standards, regulations, and guidelines have to be considered in this early phase of material development. 7/14
  9. 9. 1 22 33 3rd Step: Detailed LCA, LCC, and optimization of most promising geopolymers 1st Step: Screening of mineral raw materials 2nd Step: Streamlined LCA, LCC, and key properties of geopolymers Development of geopolymers for specific applications Figure 3: Development of geopolymers for specific applications. The approach comprises three steps of investigation The approach is subdivided into three single steps (Figure 3): First step The first step is characterized by a screening of the solid raw materials. This has to be carried out in the early phase of material development (Figure 1) where only few information are available. Therefore several qualitative attributes were used. Overall 53 raw materials (binding materials) were considered, activated with one standard alkaline activator. To rank the different raw materials, a two-stage process is developed (Figure 4). The first stage considers the technical attributes only, the second stage considers all attributes (technique, economy, and ecology/health). In both, MCDA tools (Zimmermann and Gutsche, 1991) are used to identify the most promising raw materials for certain application fields. Less promising raw materials will be excluded from further investigations. 8/14
  10. 10. Objectives Economy Ecology/HealthTechnique a1 a2 ... an b1 b2 ... bn c1 c2 ... cn Stage 1 Stage 2 Attributes Figure 4: Two-stage process. The objectives technique, economy, and ecology/health and their measurable attributes Second step In the second step, technical key properties (e.g. acid resistance) of material combinations are investigated. This technical investigation is accompanied by streamlined Life Cycle Assessment (LCA) and Life Cycle Costing (LCC). The results are used to identify the most promising material combinations for specific application fields. In this step, geopolymer material combination will be compared with products existing in the respective field of application to also obtain further information for the optimization process during the third step. Less promising geopolymer material combinations will be excluded from further investigations. Third step The third step is characterized by the optimization of the most promising geopolymer material combination for a set of specific applications. A detailed LCA and LCC regarding a specific application will be made for both geopolymeric and existing products. The results will reveal not only proven profiles of properties (technical, economic, ecological), but also indicate in which applications geopolymers possess a competitive position. 3.4 First Step of the Approach This section shall deal with the first step exclusively. 9/14
  11. 11. The aim of the first step is the evaluation and ranking of different raw materials for certain fields of application. Three objectives (criteria), which are measured with attributes (indicators), will be considered (see Figure 4): Technique - reactivity (quantitative) - mechanical strength (quantitative) - resistance against acids (qualitative) - temperature resistance (quantitative) - fast setting (quantitative) - workability (qualitative) Economy - raw material costs (quantitative) - costs of the thermal activation of raw materials (qualitative) - costs of grinding raw materials (qualitative) - follow-up costs caused by slow setting (qualitative) - follow-up costs caused by high water sorption (qualitative) Ecology/Health - availability/consumption of mineral resources (quantitative) - consumption of energy resources (qualitative) - toxic load (qualitative) - health and safety at the workplace (qualitative) The different quantitative and qualitative indicator values are comparable and countable, as they are transformed into values between 0 and 1 . Values close to 0 are less favorable, values close to 1 are very favorable. For each attribute, a proper scale of transformation has to be determined, cf. (Buchwald et al. 2005b). This will be illustrated by the example of the attributes of toxic load: Toxic load: Information about the toxic load is deduced from the content of heavy metals. The content was compared to limit values for the use of secondary recourses (Z2, restricted usage) in Germany (LAGA 2003). Numerical values are given, if the raw material: - Does not reach any limit (1), - exceeds the limit only slightly in some cases (0.8), 10/14
  12. 12. - exceeds the limit slightly very often (0.6), - exceeds the limit considerably in some cases only (0.4), - exceeds the limit considerably in some cases and slightly often (0.2) - exceeds the limit considerably very often (0). Exceeding of the chromium limit leads to a strong devaluation because of the oxidation from chromium-(IV) to chromium-(VI) in alkaline media. The ranking will be made for all application fields considered. A two-stage process was used (Figure 4). In an expert panel, it was determined that the technical aspects in the early phase of material development (Figure 1) were to be superior to economic and ecological aspects. Therefore, only technical aspects were considered in the first stages to identify and exclude the less promising candidates. Stage 1(ranking with respect to technical aspects): The AHP-Method (Satty 1980) is used to elicit the weightings of the different technical attributes (indicator) with respect to the specifications of the application. That means, that the different weightings depends very strong on the required specifications in the application fields. The elicitation of the weightings has to be done for all application fields considered. By calculating all different raw material alternatives with the different set of weightings, a ranking order of all raw materials is obtained for each application field. Less promising alternatives (with low values) are excluded from the next ranking step. The cut-off value has to be determined by an expert panel. Stage 2 (ranking with respect to technical, economic/ecological aspects): After the first stage, the alternatives remaining in each application field are ranked with respect to technical, economic, and ecological aspects. The weighting factors of the different objectives (technique, economy, ecology) will based on a survey which will published elsewhere. The result of a new calculation is a new ranking order of the raw materials. Again, the less promising materials in each application field are excluded from further investigations. 11/14
  13. 13. Compared to the weighting procedure in stage 1,which is based on the requirements of the application fields, the weighting of the objectives technique, economy and ecology in stage 2, which is based on a survey, is an even more critical point in the presented approach. In addition to the AHP method, the “dominance concept” (Eisenführ and Weber 2003) without weighting of the objectives (criteria) will therefore be applied, to identify the less promising candidates. The results of both investigations will be compared. After this, the promising raw materials can be used in step two of the approach (Figure 3) to develop and optimize raw material combinations for specific application fields. The preliminary results of this first step are published in Buchwald et al. (2005b) and Weil et al. (2005). 4 Conclusions The sustainable development of materials with enhanced properties, but also with economic and ecologic advantages is one of the challenges of modern materials science. In practice, economic and ecological aspects are considered rarely, which is probably due to the low level of information available in the early phase of material development. Based on the example of the development of geopolymers, the authors presented a methodological approach to integrating technical, economic, and ecological aspects in the early stages of material development. The approach is subdivided into three single steps. It is started from a broad variety of raw materials, which will be reduced step by step to a few promising material combinations for specific applications. This course of action is supported by the use of systems analysis tools. Besides LCA, LCC and MFA especially Multi-criteria Decision Analyses tools play a prominent role. Acknowledgements This paper was drawn up with the financial support of the Volkswagen-Stiftung, Germany. 12/14
  14. 14. 5 References Bakharev, T. (2005) Resistance of geopolymer materials to acid attack. Cement and Concrete Research, Volume 35, Issue 4, April 2005, pages 658- 670 Buchwald, A., Dombrowski, K. and Weil, M. (2005a) The influence of calcium content on the performance of geopolymeric binder especially the resistance against acids. Geopolymer Conference 2005, Saint- Quentin, France Buchwald, A., Dombrowski, K. and Weil, M. (2005b) Evaluation of primary and secondary materials under technical, ecological and economic aspects for the use as raw materials in geopolymeric binders. 2nd International Symposium. Non-Traditional Cement & Concrete, 2005. Brno, Czech Republic Davidovits, J. (1976) Solid-phase synthesis of a mineral block polymer by low temperature polycondensation of aluminosilicate polymers. I.U.P.A.C. International Symposium on Macromolecules, Stockholm; Sept. 1976; Topic III, New Polymers of high stability Davidovits, J. (2002) Environmental Drivers. International Conference Proceedings of Geopolymer 2002. Melbourne, Australia, 2002 DIN EN ISO 14040ff (1997) Environmental Management – Life Cycle Assessment – Principles and Framework. Berlin: DIN (Deutsches Institut für Normung), 1997 Eisenführ, F. and Weber, M. (2003) Rationales Entscheiden. Springer-Verlag, Berlin Heidelberg New York, 4. edition, 2003 European Commission -EU- (2004) Development of horizontal standardized methods for the assessment of the integrated environmental performance of buildings. EWG 04/081A (Construction Product EPDs) Fernandez-Jimenez, A. and Palomo, A. (2003) Alkali Activated Fly Ashes: Properties and Characteristics. Proceedings of 11th International Congress on the Chemistry of Cement (ICCC), 2003 Durban, South Africa, pages 1332 –1339 13/14
  15. 15. Bakharev, T. and Sanjayan, J.G. (2002) Alkali-activated slag concrete: Durability in aggressive environment. Geopolymer 2002, Melbourne, Australia Hermann, E., Kunze, C., Gatzweiler, R., Kiesslig, G., Davidovits, J. (1999) Solidification of various radioactive residues by geopolymer with special emphasis on long-term-stability. Geopolymer 1999, Saint- Quentin, France Länderarbeitsgemeinschaft Abfall -LAGA- (2003) Anforderungen an die Stoffliche Verwertung von mineralischen Reststoffen /Abfällen. Technischen Regeln Saaty, T.L. (1980) The Analytical Hierarchial Process. McGraw Hill Company, New York, 287 p. Weber, M. and Eisenführ, F. (1993) Behavioural influence on weight judgements in multiattribute decision making. European Journal of Operational Research, Volume 67, Issue 1, May 1993, Pages 1-12 Weil, M., Dombrowski, K. and Buchwald, A. (2005) Development of Geopolymers Supported by Systems Analysis. 2nd International Symposium. Non-Traditional Cement & Concrete, 2005. Brno, Czech Republic Zimmermann, H.J. and Gutsche, L. (1991) Multi-Criteria Analyse. Springer- Verlag, Berlin Heidelberg New York 14/14

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