Life Cycle Assessment and Environmental Product Declaration of Forestry related Products and Processes - a Way to meet Environmental Objectives.

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1 Life Cycle Assessment and Environmental Product Declaration of Forestry related Products and Processes - a Way to meet Environmental Objectives. Athanassiadis Dimitris, PhD Life Cycle Assessment specialist, Post Doctoral Fellow, FERIC, Eastern Division. Dimitris.Athanassiadis@ssko.slu.se ABSTRACT -The demand for quantified and verified information about the environmental performance of products and services constantly increases. A number of environmental tools that can help companies to understand and measure the environmental impacts associated with their products, processes, and activities has emerged e.g. Design for the Environment (DfE), Life Cycle Assessment (LCA) and many more. LCA is a systematic set of procedures for compiling and examining the inputs and outputs of materials and energy and the associated environmental impacts directly attributable to the function of a product or service system throughout its life cycle. The aim of the study was to describe the environmental performance of a forwarder crane in a life cycle perspective taking into account the following stages of the crane's life time; (1) raw material acquisition and intermediate processing (2) fabrication of individual components and assembly of the crane, (3) associated transports and (4) use. It was found that a forwarder crane will consume 1050 MWh of energy during its lifetime while at the same time 360 tonnes of CO 2 equivalents (CO 2, CH 4, etc) will be released into to atmosphere. 97 of that amount of energy and 98 of the CO 2 equivalents were due to the use phase. The results were used to prepare an Environmental Product Declaration (EPD) for the forwarder crane. With the help of EPD:s, products that perform the same function can be compared to each other with respect to energy and resource consumption and associated s to air, water and soil, tied to system performance and final product produced. INTRODUCTION Industrial activity is a major contributor to environmental deterioration. Due to a prevailing pressure from markets and governments, companies and organisations pursue to improve their environmental performance. A number of environmental tools that can help companies to understand and measure the environmental impacts associated with their products, processes, and activities has emerged e.g. Design for the Environment (DfE), Life Cycle Assessment (LCA) and many more. These tools are drawn up differently depending on whether they focus on product and service systems, plants and installations or specific sites. LCA is one of many tools for studies of the environmental dimension in sustainability; it is an analytical and mainly quantitative tool that has a perspective of product rather than site. It is a systematic set of procedures for compiling and examining the inputs and outputs of materials and energy and the associated environmental impacts directly attributable to the function of a product or service system throughout its life cycle - with a cradle to grave approach, from raw materials acquisition through production, use and disposal. This is done by compiling an inventory of relevant inputs and outputs of a system; evaluating the potential environmental impacts associated with those inputs and outputs; and finally interpreting the results of the inventory and impact phases (ISO 1999). LCA applications include identifying process-related improvement options, eco-labelling of products, and comparison of alternative product systems. Cranab AB commissioned the Swedish University of Agricultural Sciences (SLU), to carry out an LCA for one of its forwarder cranes. The aim of the commissioners was to acquire a certified environmental product declaration (EPD). The company was the first manufacturer concentrating on forestry cranes to be approved in accordance with the international ISO environmental standard and is also EMAS registered. The EPD system is an attempt to apply ISO TR (a normative technical report for provisional use in the field of Type III environmental declarations) in practice. The system is based on LCA, according to ISO standards. The company aimed to use the results from the LCA in product development; that is identify opportunities to improve the environmental performance of the product at various points in its life cycle. The aim of the study was to describe the environmental performance of a forwarder crane based on a life cycle assessment by taking into account the following stages of the life cycle of the crane; (1) raw material acquisition and intermediate processing (referred to in the tables as raw material) (2) fabrication of individual components and assembly of the crane (refereed to in the tables as fabrication), (3) associated transports (raw material to component manufacturers, components to assembly factory, complete crane to final customer) and (4) use. MATERIAL AND METHODS The CRF 8 forwarder crane was examined. The technical life expectancy of the crane was set to crane cycles and the production capacity of a forwarder with the CRF 8 throughout its lifetime was set to m 3

2 overbark (vob). The reference flow (functional unit) of the study is 1000 m 3 vob at the roadside. All energy and materials consumed as well as s to the environment were normalized to the functional unit. The functional unit is crucial as it defines a product s performance and enables comparisons between EPD:s. The main components of the forwarder crane are the slewing motor, the pillar, the main boom, the outer boom, the grapple, the hydraulic cylinders, the rotator, and the hydraulic hoses (Figure 1). These are either manufactured at Cranab or at suppliers and transported to Cranab (mainly by truck). The material composition of the crane was decided by examining each component. The contribution of the materials to the total mass of the crane was the following (in kg); Steel/iron: 1960, bronze: 1.2, brass: 7, nitrile rubber: 2, Polyethylene (High Density): 3, Ethylene Propylene Diene: 21, polypropylene 5. Figure 1. The CRF 8 forwarder crane Environmental data (amount of input materials, energy consumption, solid waste generation and air/water pollutant release) were collected for all life cycle stages of the crane. The system boundaries and data collection sources/methods are shown in Table 1. Table 1 The system boundary and data collection methods and sources for the forwarder crane LCA Life cycle Data collection method/source stages Databases consulted: International Iron and Steel Raw material Institute, Association of Plastics Manufacturers in Europe, PRe4, Buwal 250 Fabrication Suppliers Data provided by suppliers by means of a questionnaire. Emission factors for energy sources as in Athanassiadis et al. (2002) Transport Use In-house Data was directly measured and/or provided by Cranab. Emission factors as above Data provided by suppliers and Cranab. Database consulted: Network for Transport and the Environment Brunberg et al. 2000, Athanassiadis 2000a & 2000b The crane contains at least 15 of recycled steel. For that reason, environmental benefit from recycling of the crane was left out of the boundaries of the study. Several, but not all, of the manufacturing processes at the suppliers were taken into account. Use phase modelling included fuel consumption and hydraulic oil consumption (3 l/ 1000 m 3 vob) by the forwarder, fuel consumption for the transport of the forwarder between logging sites and parts replacement requirements (mainly hydraulic hoses) of the crane (25 kg steel and 20 kg Ethylene Propylene Diene/1000 m 3 vob). Forwarder fuel consumption strongly depends on vehicle size, engine power, travel distance, load size, log and bunch size, grapple volume, terrain conditions and operator skill. In the case of the 14 ton forwarder with the CRF 8 fuel consumption was estimated to 9.5 l per hour. 70 of that was judged to be due to the crane. The data were classified into five environmental impact categories such as global warming, eutrophication etc. (Figure 2). CO 2 NO x HC SO x CFC-11 Global Warming (g CO 2 ) Acidification (g SO 2 ) Eutrophication (g O 2 ) Photochemical Ozone Creation (g ethene ) Ozone Depletion (g CFC-11 eq) Figure 2. Flow process for calculation of the environmental impact

3 The impact was quantified with the aid of a category indicator. For the global warming environmental impact the category indicator is the global warming potential (GWP), expressed as CO 2, of each greenhouse gas (e.g. CH 4 equals to 21 CO 2, N 2 O equals to 310 CO 2 etc.). The environmental impacts and associated category indicators that were used are those recommended by the Swedish Environmental Management Council (2000). The environmental impacts are shortly described in Table 2. Table 2. Description of the environmental impacts handled with in the study Greenhouse effect Acidification Eutrophication Photochemical ozone formation Ozone depletion The so called greenhouse gases have the capacity to absorb and re-emit heat energy radiated from the surface of the earth thus causing changes in the Earth's climate and weather patterns. Climate change would have profound effects on the Earth's ecosystems, landforms and human society. The potential of gases to absorb and reradiate heat energy, and thereby intensify the greenhouse effect is expressed in CO 2 equivalents. Acidification is defined as a decline in nature s ability to neutralise acid precipitation, which in turn lowers the ph of lakes and soil. In the terrestrial ecosystem the effects are seen in softwood forests (e.g. spruce) as inefficient growth and as a final consequence dieback of the forest. In the aquatic ecosystem the effects are seen as acid lakes without any wildlife. The acidification potential of substances is expressed in SO 2 equivalents Oxygen is consumed by the biological degradation of organic substance that is emitted to the sea and lakes. The decomposition of organic material is an oxygen consuming process leading to decreasing oxygen content of the water. This leads to a deterioration of the water quality and a reduction in the value of the utilisation of the aquatic ecosystem. The acidification potential of substances is expressed in O 2 equivalents. Photochemical ozone formation is caused by degradation of organic compounds in the presence of light and nitrogen oxides. Exposure of plants to ozone may result in plant dieback. Exposure of humans to ozone may result in eye irritation, respiratory whole plant. problems, and chronic damage of the respiratory system. The contribution of organic compounds to ozone formation is expressed in ethene equivalents. Ozone in the upper atmosphere forms a shield that protects the earth from ultraviolet (UV) radiation. A diminished ozone layer allows more radiation to reach the Earth's surface. Increased UV radiation can have harmful effects on human health, plants, and marine ecosystems. The potential of gases to deplete the ozone layer is expressed in CFC-11 equivalents.

4 RESULTS About 97 of the total amount of energy needed to manufacture and operate a forwarder crane is consumed at the use phase. During its lifetime the crane will need 1050 MWh in form of diesel fuel (100 tons of diesel oil). At the same time the crane will handle about m 3 of wood. In energy terms this amount of wood equals to more than MWh. Steel producing was the second more significant stage in the life cycle of the crane. Steel is a central material in the crane comprising 98 of its mass. The process of making steel uses significant amounts of energy (6 kwh/ kg steel produced) and significant amounts of carbon dioxide are released (558 g/kg steel). Carbon dioxide (CO 2 ), nitrogen oxides (NOx), sulphur oxides (SOx), hydrocarbons (HC) and particle s are some of the main s that cause a great impact to the environment and are mostly determined by the amount of energy consumption. The amount of these s from the different life cycle stages of the crane are shown in Table 3. Table 3. Amount(g/1000 m3 vob) of selected s for the life cycle stages of the forwarder crane. Life cycle stages CO 2 NOx SOx HC Particle s Raw material Fabrication Transport Use The magnitude of environmental impacts in each of the crane's life cycle stages is shown in Table 4. Based on the impact assessment results, the major contributors to environmental problems at each stage were identified. Table 4 Energy use and environmental impact per 1000 m 3 vob for the life cycle stages of the forwarder crane. Life cycle stages Raw material Fabrication kwh Energy use and environmental impacts g CO 2 g SO 2 g ethene g O Transport Use TOTAL Most environmental impacts occur at the use stage owing to the s from fuel combustion. The material acquisition and intermediate processing stage follows the use phase in terms of amount of energy consumed and contribution to the global warming impact category. None of the in-house and at suppliers manufacturing stage processes involved a lot of s except the painting process where some solvents were emitted affecting the photochemical ozone creation potential of the crane. It is clear that transports cause only a minor part of the s (Table 4). CONCLUSIONS Using LCA methodology priorities for environmental improvements can be set. In the case of the forwarder crane it is apparent that fuel consumption and s to air during the operation phase should be targeted for reduction. This can be achieved by shifting to modern engines that consume less fuel or emit fewer pollutants. By using a low sulphur diesel oil, the SOx s and thus the acidification potential of the system can be reduced substantially. At the manufacturing stage solvent s could be reduced by substituting solvent borne by water borne paints. Through an accredited certification body an external review of the study was conducted. It was confirmed that the data and the declaration is in conformance with the requirements for a certified Environmental Product Declaration. The final document, the first to be issued world-wide for a forest machine component, was approved on November 2001 and the EPD certification was issued shortly after the approval. The use of LCA has expanded among companies and organisations around the world and is more commonly regarded a strategic tool for a rational and preventive environmental work. In general LCA could be used for many purposes e.g.: in product development work to identify opportunities to improve the environmental performance of products and services at various points in their life cycle

5 in environmental management work as a base for a methodological approach in identifying significant environmental aspects and thereby assisting in setting targets and objectives within the framework of an environmental management system in communication and marketing giving a holistic basis for describing the environmental performance of products and services. ACKNOWLEGMENTS The project has been very successful in achieving its aims. The author and project leader acknowledges the valuable contribution of the project team (Jan Kärnestad, Cranab and Nina Åkerback, SYH) and of the members of the Reference Group (Stina Frejman, SYH; Ola Kåren, Holmen; Kjell Rönnholm, Cranab; Ulf Wiklund Tyréns and Iwan Wästerlund, SLU) who gave generously of their expertise at key points during the project. Further, the involvement of many of the employees at Cranab and suppliers is acknowledged and greatly appreciated. REFERENCES Athanassiadis D. 2000a. Energy Consumption and Exhaust Emissions in Mechanised Timber Harvesting Operations in Sweden. Science of the Total Environment 255(1-3): Athanassiadis 2000b. Resource consumption and s induced by logging machinery in a life cycle perspective. Doctoral Thesis. Swedish University of Agricultural Sciences, Department of Silviculture, Section of Forest Technology. Acta Universitatis Agriculturae Sueciae. Silvestria 143. Athanassiadis. D., G. Lidestav, and T. Nordfjell Energy Use and Emissions due to the Manufacture of a Forwarder. Resources Conservation and Recycling : 34(3) Brunberg, T., G. Eriksson, P. Granlund, B. Löfgren, C. Löfroth, B. Nordén Test av åtta mellanstora skotare - tekniska data och bränsleförbrukning. Skogforsk. Resultat nr 20, 4 pp. (in Swedish with English summary) International Standards Organization, ISO 14041: Environmental management - LCA - Goal and scope definition and inventory analysis Swedish Environmental Management Council, Requirements for Environmental Product Declarations - EPD an application of ISO TR Type III environmental declarations. MSR 1999:2.

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