Ecology meets economy. Eco-Efficiency Analysis of water-based ink systems for PE film applications.

Transcription

1 Ecology meets economy Eco-Efficiency Analysis of water-based ink systems for PE film applications.

2 The Eco-Efficiency Analysis makes sustainability measurable Contents Input and methodology Customer benefit and alternatives 04 System boundaries 04 Model parameters 06 BASF label to mark eco-efficient products Environmental impact categories The eco-efficiency portfolio according to BASF 08 Environmental impact categories 08 Fingerprints Ecological fingerprint 12 Costs summary 13 Results Conclusions 14 Method for Eco-Efficiency Analysis is validated by NSF International Method for Eco-Efficiency Analysis is validated by the German Association for Technical Inspection (TÜV) Growing expectations growing responsibility About the Eco-Efficiency Analysis Consumers continue to expect more from the packages that deliver and protect the products they consume. In response brand owners strive to innovate with new package designs, materials and user-friendly features. With increasing legislation and pressure to create sustainable packaging, brand owners and retailers are starting to explore alternatives to conventional approaches. Creating packaging that is sustainable on an environmental, social and economic level is key to providing value to the consumer, maintaining the competitive edge and adhering to current regulations. Market interest in environmental information on products that is credible, unbiased, verifiable, and covers the entire life cycle is growing. Life cycle assessment tools have become an important quantitative tool to validate the environmental impacts and claims of products and processes. This Eco-Efficiency Analysis (EEA) was conducted comparing two ink technologies used in the printing of low-density polyethylene film for the European market, such as used to produce shopping bags. The analysis is based on the 2008 US study with adjustments to the European conditions in the following categories: ink composition, material and labor costs, printing conditions risk and toxicity potential European weighting and relevance factors methodology updates Developed by BASF in 1996, the Eco-Efficiency Analysis compares the economic and environmental impacts that products and processes have over the course of their

3 Life cycle: cradle to grave transportation products product application landfilling recovery of raw materials energy production incineration/recycling production use disposal life cycle. In the economic dimension materials, energy, waste, capital, labor and the cost of EHS programs are considered. The environmental impacts assessed are energy consumption, material consumption, land use, worker health effects, risk potential, wastes and emission to air and water. In this eco-efficiency study a functional output, or customer benefit (CB), was defined as the production, use and disposal of 1,000 m 2 of flexographic printed LDPE film. Two ink systems were evaluated; water-based and solvent-based which were thermally dried. The model assumed a 4-color CI flexographic wide-web printing press with an ink coverage of 40 % on the polyethylene film. Processing variables taken into account applied wet and dry ink film weight, percent ink solids and energy to operate the printing equipment and cure the ink. The most eco-efficient alternative is the water-based ink based on Joncryl FLX The results show that the water-based ink system has a lower overall environmental impact in addition to lower life cycle costs. The lower material input (due to water used as diluent) is primarily responsible for this good performance. Inks are the main driver of environmental impact, but energy use associated with printing and curing has a significant impact on various environmental impact categories (energy, air emissions, land use)

4 Input and methodology of the Eco-Efficiency Analysis Customer benefit and alternatives System boundaries The alternatives compared in this EEA study consist of water-based and solvent-based printing inks. The Customer Benefit (CB), or defined level of output, for this study was defined as the production, use and disposal of 1,000 m 2 of LDPE flexographic printed film with a 40 % solid image coverage area on a 4-color CI (Central Impression) press. The scope of any EEA is defined by its system boundaries, which define the specific elements of production, use, and disposal that are considered as part of the analysis. The production, use and disposal phases of the printing inks differed slightly between the alternatives; therefore, the environmental and economic impact analysis focused on all three phases for each printing ink alternative. Customer benefit and printing ink alternatives Joncryl FLX 5000 styrene acrylic water-based thermally cured Customer benefit: printing 1,000 m 2 of LDPE film 40 % image coverage 4-station press Europe solvent-based nitrocellulose polyurethane solvent-based thermally cured

5 System boundaries of water-based ink based on Joncryl FLX 5000 System boundaries of solvent-based ink Raw materials: acquisition and transportation Raw materials: acquisition and transportation Production acrylic emulsion wax emulsion phthalo blue pigment silicon emulsion water styrene acrylic resin Production polyurethane ethanol n-propyl acetate nitrocellulose PE wax phthalo blue pigment adhesion promoter natural gas electricity steam water ink LDPE film natural gas electricity steam solvent ink LDPE film Use natural gas ink printed on flexible film electricity Use natural gas ink printed on flexible film electricity Disposal film disposal ink disposal Disposal VOC abatement film disposal ink disposal 04 05

6 Input and methodology of the Eco-Efficiency Analysis Model parameters The assumptions and inputs in this study were modeled on manufacturer equipment specifications, and not collected from a live printing run. The ink, processing and energy parameters utilized for this study are given in the tables below. A general assumption was made that the printed film scrap made during production was the same for both ink scenarios. Water-based ink composition Solvent-based ink composition FLX water Heliogen Blue D % Solvent Heliogen Blue D % Joncryl HDP % polyurethane 7.0 % Joncryl FLX % nitrocellulose dry 9.0 % Joncryl WAX % polyethylene wax 1.0 % surfactant 1.0 % adhesion promoter 2.0 % defoamer 0.5 % maleic resin 2.5 % water 12.0 % n-propyl acetate 13.0 % total % ethyl acetate 3.0 % ethanol 50.0 % total %

7 Summary of ink and processing variables Summary of energy parameters Parameter FLX SB Parameter FLX SB Ink variables solid content [%] Electricity driver power [kw] weight per liter [kg] inter-station - drying [kw] - - printed weight wet [g/m 2 ] inter-station - blower [kw] printed weight dry [g/m 2 ] main (final)-drying [kw] - - ink selling price [EUR/kg] main (final)-blower [kw] Processing variables ink coverage (image) [%] Natural gas inter-station-drying[mj/hr] web width [m] main (final)-drying[mj/hr] 1,203 1,013 web speed [m/min] total [MJ/hr] 2,005 1,688 Ink consumption wet ink usage (kg/hr) total [MJ/CB] 5,568 4,689 wet ink usage (kg/hr)

8 MJ/CB Environmental impact categories of the Eco-Efficiency Analysis Weighting factors of the different environmental impact categories Environmental impact categories 600 energy consumption land use 500 risk potential toxicity potential 200 resource consumption 100 energy consumption 0 FLX SB emissions 0 % 5 % 10 % 15 % 20 % 25 % 30 % VOC abatement curing drive power/energy truck diesel use inks The eco-efficiency portfolio according to BASF 1,2 BASF has developed the eco-efficiency portfolio to allow a clear illustration of eco-efficiency. The overall cost calculation and the calculation of the ecology fingerprint constitute independent calculations of the economic and environmental considerations of a complete system with different alternatives. The environmental and economic aspects are considered and weighted equally in an eco-efficiency analysis. The environmental impact is characterized using the following categories: primary energy consumption, resource consumption, toxicity potential, risk potential, water emissions, solid waste generation, land use and air emissions (global warming, acidification, ozone depletion and photochemical ozone creation potential). The global warming and acidification potential are the potentials with largest impact on the air emissions. Environmental impact categories Energy consumption The impact category energy consumption is based on the consumption of primary energy over the whole life cycle and includes conversion losses for electricity and steam generation. In the case of BASF processes, company-specific data is used. In the case of non-basf processes, the UCPTE data set 3 is used. In order to calculate the total energy requirement, the lower calorific value of the primary energy equivalent is used. The following forms of energy are taken into account: coal, oil, gas, lignite, nuclear energy, hydraulic power, biomass and others. The figure energy consumption shows that solvent-based ink has the highest overall energy consumption. The ink formulation is the largest single contributor, but also the energy consumption during printing and curing is critical. Resource consumption To determine the resource consumption, first the mass of raw materials necessary for each alternative is determined. The individual materials are weighted according a factor incorporating that reflects the demand and the exploitable reserves of a raw material 4. The figure resource consumption shows that the ink

9 kg silver-eq/cb toxicity potential points [weighted] risk potential points [weighted] weighted land use m2a/cb resource consumption 0.20 toxicity potential 6.0 risk potential 0.6 land use FLX SB 0.00 FLX SB 0.0 FLX SB 0.0 FLX SB VOC abatement curing drive power/energy truck diesel use inks ink use diesel electricity & gas ink production VOC abatement curing drive power/energy truck diesel use inks VOC abatement curing drive power/energy truck diesel use inks formulation dominates resource consumption, but high electricity use during printing and curing also contributes significantly. Water-based ink contains less organic material and thus has lower resource consumption than solventbased ink. Toxicity potential The toxicity potential is based on the R-phrases of all substances involved (incl. the pre-chain). Water-based ink usage is not associated with any R-phrases, while solvent-based ink is R10 (flammable), which has no direct human toxicological effect. Land use Area is not consumed like a raw material but, depending on the type, scope and intensity of the use, is changed so radically that it is impaired or even destroyed in its ability to perform its natural function. Area necessary to fulfill the customer benefit is considered for each alternative. The area requirement is assessed by weighting according to principal type of use and in relation to the relevance of the area requirement. Land use is dominated by secondary energy production. It is very similar for both printing ink technologies. Risk potential The risk potential covers the physical hazards during the production, use, and disposal phases and also considers the risk of explosion, flammability, storage accidents, worker illness and injury rates, malfunctions in product filling/packaging, transportation accidents, and any other risk deemed relevant to the study. For this analysis the risk potential is based on statistics for occupational accidents and illnesses associated with energy and chemical production and use. 1 P. Saling, A. Kicherer et al, Int. J. LCA 7 (4), , (2002) 2 A. Kicherer, S. Schaltegger, H. Tschochohei, B. Ferreira Pozo Int J LCA 12 (7) (2007) 3 West European Electricity Coordination System (UNION POUR LA COORDINATION DE LA PRODUCTION ET DU TRANSPORT DE L`ÉLÉCTRICITÉ) 4 U.S. Geological Survey, Mineral Commodity Summaries, 1997; Römpp Chemie Lexikon, Thieme, Stuttgart; Institut für Weltwirtschaft, Kiel; D. Hargreaves et al, World Index of Resources and population, Dartmouth Publishing, 1994; World Resources, Guide to the Global Environment, Oxford 1996; Deutsches Institut für Wirtschaftsforschung, Berlin 08 09

10 Environmental impact categories of the Eco-Efficiency Analysis Weighting factors weighting factor emissions weighting factor air emissions 24 % emissions 11 % - air emissions 8.0 % 11.0 % 5.0 % 4.8 % 5.0 % 1.3 % 0.3 % 0 % 5 % 10 % 15 % 20 % 25 % 30 % water emissions air emissions solid wastes 0 % 2 % 4 % 6 % 8 % 10 % 12 % global warming potential (GWP) acidification potential (AP) ozone depletion potential (ODP) photochemical ozone creation potential (POCP) Emissions Emissions consist of solid waste and emission to the water and air. In the figure above the weighting factors are given. Air emissions Air emissions of different gases are recorded separately and added up over the whole life cycle. The impact categories that are taken into consideration in the eco-efficiency analysis are the global warming potential, photochemical ozone creation potential (summer smog), acidification potential (acid rain) and ozone depletion potential. The above figure shows their relevance factor into the air emissions category. In most processes, the emission of carbon dioxide is the largest air emission. All emissions occurring during the life cycle are considered, for example for the generation and use of electricity. The effect of these air emissions in the environment varies depending on the type of gas. In order to take account of this, the various emission quantities are linked to scientifically determined assessment factors 1. Using this method, the emissions of 21 kg of carbon dioxide have the same greenhouse effect as 1 kg of methane. These so-called impact factors are used for each emission. Some emissions play a role in several impact categories. Ethanol use in the solvent-based ink formulation results in a large contribution in the acidification potential compared to the water-based alternative. The main contributors to the GWP of each alternative include the CO 2 emitted during the ink formulation, drive power, and curing stages. Additionally, the solvent-based ink system contains a VOC abatement stage that has a

11 g CO 2 -equivalent/cb critical waste water volume I/CB weighted kg/cb Emissions 35,000 global warming potential 10,000 water emissions 0.8 solid wastes 30,000 25,000 8, ,000 15,000 6,000 4, ,000 5,000 2, FLX SB 0 FLX SB 0.0 FLX SB VOC abatement curing drive power/energy truck diesel use inks VOC abatement curing drive power/energy truck diesel use inks VOC abatement curing drive power/energy truck diesel use inks measurable impact on GWP, which contributes to the fact that it is the least desirable alternative from a carbon footprint standpoint. The highest carbon footprint occurred in the solvent-based printing ink alternative, with a measurement of almost 30 kg of CO 2 equivalents per customer benefit. The water-based printing ink system has an emission of about 16 kg of CO 2 equivalents per customer benefit. The result is almost 50 % reduction in the carbon footprint for the waterbased alternative when compared to solvent-based. Water emissions Water emissions are taken into account for 8 % in the emission category. The assessment of water pollution is carried out by means of the critical volume model. For selected pollutants that enter the water, the theoretical water volume affected by the emission up to the statutory limit value (critical load) is determined. The volumes calculated for each pollutant are added up to yield the critical volume. Water emissions are dominated by inks. Water-based ink again has the advantage of containing less material (i.e., excluding water) than solvent-based inks. Solid wastes Solid wastes occur during production of the ink components; wastes due to energy generation are negligible. The water-based ink systems can reduce the amount of solid waste generation drastically compared with its alternatives as shown in the figure above. 1 UBA Texts 23/

12 Fingerprints of the Eco-Efficiency Analysis Ecological fingerprint energy consumption land use emissions resource consumption toxicity potential Joncryl FLX risk potential solvent-based Ecological fingerprint The impact categories are normalized (and, in the case of emissions, also aggregated) and plotted on the ecological fingerprint. This plot shows the ecological advantages and disadvantages of the alternatives relative to one another. The alternative with a value of one is the least favorable alternative in that category; the closer an alternative is to zero, the better its performance. The axes are independent of each other so that an alternative which is, for example, favorable in terms of energy consumption may be less favorable in terms of emissions. Using the ecological fingerprint, it is possible to find the areas in which improvements are necessary in order to optimize the whole system effectively.

13 EUR/CB Life cycle costs FLX SB wastes handling thermal oxidizer labor electricity natural gas inks Costs summary Ink is the largest contributor to the total costs and is about 15 % higher for solvent-based inks, despite the higher kg ink price of water-based inks. Labor also contributes significantly to total costs and is similar for the different printing technologies

14 environmental impact (norm.) Results of the Eco-Efficiency Analysis Conclusions The figure below shows the overall environmental impact and life cycle costs. To obtain the overall environmental impact, the individual environmental impact categories are aggregated according to the weighting factors mentioned earlier. Because environmental impact and cost are equally important, the most eco-efficient alternative is the one with the largest perpendicular distance above the diagonal line. For this study the water-based ink system is the more eco-efficient alternative due to its lower environmental impact and lower costs relative to the solvent-based alternative. The BASF Eco-Efficiency Analysis continues to be a valuable tool for suppliers, manufacturers and end-users to make informed and educated decisions about raw material selections for printed products. Overall environmental impact and life cycle costs 0.0 Customer benefit Joncryl FLX printing 1,000 m 2 of LDPE film % image coverage 4-station press Europe solvent-based costs (norm.)

15 Result water-based ink is the most efficient alternative due to lower environmental impact and lower cost 14 15

16 Contact BASF SE Success-Info-Point Ludwigshafen Germany Tel.: Fax: BASF Nederland B.V. Resins & Additives Innovatielaan SN Nijehaske P.O. Box AJ Heerenveen The Netherlands Tel.: Fax: resins@basf.com The data contained in this publication are based on our current knowledge and experience. In view of the many factors that may affect processing and application of our product, these data do not relieve processors from carrying out their own investigations and tests; neither do these data imply any guarantee of certain properties, nor the suitability of the product for a specific purpose. Any descriptions, drawings, photographs, data, proportions, weights, etc. given herein may change without prior information and do not constitute the agreed contractual quality of the product. The agreed contractual quality of the product results exclusively from the statements made in the product specification. It is the responsibility of the recipient of our product to ensure that any proprietary rights and existing laws and legislation are observed. When handling these products, advice and information given in the safety data sheet must be complied with. Further, protective and workplace hygiene measures adequate for handling chemicals must be observed. = registered trademark of the BASF Group BASF SE Ludwigshafen Germany EDC 0110 e