Thursday, October 3, 2019

Environmental impact of the life cycle of tap water with the life cycle of glass bottled water

Environmental impact of the life cycle of tap water with the life cycle of glass bottled water Abstract In this report, the Life Cycle Assessment (LCA) methodology is applied to compare the lifecycle of tap water and bottled water using the four assessment methods. The results of inventory analysis and impact assessment shows that the tap water and glass bottled water production processes play an important role in almost all of the analysed parameters. The processes that have was examined include production and transportation, the quantification of the energy used and the potential contributions to impact categories was also evaluated. It was realised that the glass bottle water production shows a relatively higher energy requirement as well as overall higher contribution to environmental impact in Climate change, ozone layer, Exotoxicity, acidification/eutrophication, respiratory organics, respiratory inorganics, radiation, carcinogens, land use and minerals. 1:Introduction Presently, industries and businesses are assessing how their activities affect the environment due to increases environmental awareness. Also, the Society is becoming more concerned about the issues of natural resource depletion and environmental degradation and many industries have responded to this awareness by providing sustainable products and using sustainable processes. Drinking water is a basic necessity, but how can this basic need be satisfied in an environmentally friendly manner. This analysis compares the entire life cycle from the water extraction to serving it up in a glass bottle in a Life Cycle Assessment (LCA). The systems that have been assessed in this study are: the production of inputs of tap water and glass bottle, transportation, energy used and the manufacturing process. This study was carried out with the use of the SimaPro 7 software for the inventory and interpretation of the analysis. Eco-indicator 99 (l) V2.02/Europe El 99 l/l was used as an assessment method in which the various materials and products are weighted with regard to the impact caused by them to the environment. 2:Benefits of conducting Life Cycle Assessment * Life cycle analysis encourages a more informed and broader view of the environmental impact of a product. It helps decision-makers select the product or process that results in the least impact to the environment. This information can be used alongside other factors, such as cost and performance data to select a product or process. * LCA helps to avoids generalisations about the environmental performance of a product in isolation to its total life cycle. Rather, it openly acknowledges the assumptions made, and tests the effects of the assumptions. * LCA allows producers and consumers to compare relatively, the significance of different types of environmental impacts with caution. * LCA helps to avoid the Shifting environmental problems from one place to another; It allows a decision maker to study an entire product system thus, avoiding a sub-optimization that could result if only a single process were the focus of the study. For example, when choosing between two rival products, it may appear that product A is better for the environment because it generates less solid waste than product B. However, after performing an LCA it might be discovered that the first product actually creates larger cradle-to-grave environmental impacts when measured across all three media i.e. air, land and water e.g. it may cause more emissions of chemicals during its manufacturing stage. Therefore, the second product that produces solid more waste may be viewed as producing less cradle-to-grave environmental harm or impact than the first technology due its lower chemical emissions. This ability to track and document shifts in environmental impacts of products can help decision makers to fully characterize the environmental trade-offs associated with product alternatives. By conducting an LCA, analysts will be able to; * Analyze the environmental trade-offs associated with one or more specific products to help gain stakeholders acceptance for a planned action. * Quantify the environmental emissions to air, water, and land in relation to each life cycle stage and the major contributing process. * Develop an efficient assessment of the environmental consequences associated with a given product. 3:Challenges encountered in conducting Life Cycle Assessment Performing an LCA could be time and resource intensive. Depending on how comprehensive the user wishes to conduct, gathering the data can be problematic, and the availability of data can greatly impact on the accuracy of the final results. Therefore, it is important to consider the availability of data, the time required to accomplish the study, and the financial resources necessary against the anticipated benefits of the LCA. Table 1 below shows the general challenges of LCA. Table 1:The general challenges and difficulties of LCA methodology. Goal definition and scoping In conducting an LCA, the cost may be prohibitive to small firms; also, the required time to conduct LCA may exceed product development constraints especially for short development cycles; the temporal and spatial magnitude of a dynamic product system are complex to address; definition of functional units for the evaluation of design alternatives can be problematic; allocation methods used in defining system boundaries have inherent weaknesses; complex products (e.g. automobiles) entails huge resources to analyse. Data collection Availability of data and access can be limiting e.g. proprietary data; data quality, including bias, precision completeness and accuracy ,are frequently not well addressed. Data Evaluation Sophisticated models and model parameters for evaluating resource depletion, human health and ecosystem, may not be available or their ability to represent the product system may be repulsive. Thus most times, uncertainty analyses of the results are often not conducted. Information transfer Design decision-makers often lack knowledge about environmental effects, and aggregation and simplification techniques may distort results. Synthesis of environmental effect categories is limited because they are incommensurable. According to (Keoleian, 2003)Both cost and time constraints currently limit the practice of LCA. Most small companies are not likely to be able to afford specializing in LCA and even for larger firms, the benefits of investment in LCA may not be apparent immediately. In some cases, possible cost savings may not be identified unless full cost accounting systems have been instituted. Therefore, in other for it to be more cost effective, it should be incorporated into the existing environmental management system and information systems within a firm. Also, LCA will not conclude on which product is the most cost effective or works the best. Therefore, the information developed in an LCA should be used as one component of a more comprehensive decision process in assessing the trade-offs with cost and performance, an example is Life Cycle Management. 4:Present quality examples of uses of LCA. One example of the uses of Life cycle assessment is its application in the pulp and paper industry. Life cycle assessment is used to compare the environmental impact of the use of two kinds of fuel i.e. heavy fuel oil and natural gas, in the pulp and paper production process. Another, LCA methodology can be applied to agricultural production. An example is the Life cycle analysis of sugar beet production using different forms of nitrogen fertilizers. It could be used in this aspect to quantify and evaluate the impact of the choice of different N fertilisers on the environmental burden associated with the sugar beet production system. Also, it could be applied in the bakery industry. An example is the life cycle analysis of bread production by comparing homemade bread or industrial bread. In this context, it could be used to compare the environmental effects of producing bread at home or at the bakery showing which type of bread production has less environmental effects and how the environmental effects can be reduced. 5:Guidance and LCA standards There are international standard which help us undertake LCAs in a standard way. The International Organization for Standardization (ISO) is a worldwide federation of national standards bodies (ISO member bodies) and the ISO technical committees produce international standards on a variety of topics. The ISO 14000 series The ISO 14000 series relates to numerous facets of environmental management. These series includes ISO 14040 14043 and they were prepared by the Technical Committee ISO/TC 207, Environmental Management Subcommittee SC 5, Life Cycle Assessment. While ISO recognizes that LCA is still in a growing stage of development, ISO 14040-14043 is a consensus-based, voluntary set of standards pertaining to LCA. ISO 14040 Environmental management Life cycle assessment Principles and framework: Specifies the general framework, principles, and requirements for conducting and reporting life cycle assessment studies, but does not describe the life cycle assessment technique in detail. ISO 14041 Environmental management Life cycle assessment Goal scope and definition and inventory analysis: Specifies the requirements and procedures for the compilation and preparation of the definition of goal and scope for an LCA and for performing, interpreting, and reporting a life cycle inventory (LCI) analysis. ISO 14042 Environmental management Life cycle assessment Life cycle impact assessment: Describes and gives guidance on the general framework for the life cycle impact assessment (LCIA) phase of LCA, and the key features and inherent limitations of LCIA. It specifies requirements for conducting the LCIA phase and the relationship of LCIA to other LCA phases. ISO 14043 Environmental management Life cycle assessment Life cycle interpretation: Provides requirements and recommendations for conducting the life cycle interpretation in LCA or LCI studies. It does not describe specific methodologies for the life cycle interpretation phase of LCA and LCI studies. (Dooley, 2002) ISO 14040:2006 Environmental management Life Cycle Assessment Principles and framework PAS2050:2008 Specification for the assessment of life cycle greenhouse gas emissions of goods and services (Patterson, 2009) These standards set out the general process that should be followed when undertaking any Life Cycle Assessment and are not legally binding or enforceable. 6:Methodological framework 6.1:General requirements This analysis was performed using a methodological framework based on ISO (International Organization for Standardization) recommendations stated above and according to ISO, there are four phases in LCA: goal and scope definition, inventory analysis, impact assessment and interpretation. 6.2:Goal and scope definition 6.2.1: Purpose The purpose of this study is the identification and assessment of the environmental impacts associated with the production, use, disposal and recycling of tap water and glass bottle water. The main reason for conducting this study is to compare the environmental impact of the life cycle of tap water with the life cycle of glass bottled water, to provide information on which of production processes has less environmental impact, to understand which of the processing stages account for the highest or lowest environmental effects and to evaluate how the environmental impacts can be reduced. 6.2.2: Functional Unit (FU) The main purpose of the functional unit is to provide a reference unit to which the inventory data are normalised. In this assessment, the appropriate functional unit of water is related to 1 kg of portable water to be consumed and the equivalent amount which is 750 grams of water in the bottle 6.2.3:Study Questions The study seeks to answer the following questions: * What are the environmental impacts of tap water and glass bottle production? * What are the different materials used in the manufacture of these two products? * Which of the production processes has less environmental impact? 6.2.4: Product description The products being assessed are glass bottle and tap water. The raw material used in the production of glass bottle are dolomite, sand, feldspar, limestone, silica sand, natural gas, 2 litres of water and electricity while the raw material used in the production of the tap water are water from lakes, water from river and underground water, chlorine, hydrogen peroxide, ozone, charcoal and electricity. 6.2.5: Product system boundaries The system being assessed produces glass bottle water and tap water using the typical life cycle stages. * Cradle to material production for glass bottle and reuse. * Treatment and distribution of tap water. 6.2.6:Process flow charts The process flow for the glass bottle is represented in figure 1 below and it includes the following; Water, dolomite, soda, limestone, feldspar, sand, silica sand, natural gas, electricity, transport and waste disposal (land filling and recycling). Figure 3:The network of the Life cycle analysis of the glass bottled water. Figure 4:The network of the Life cycle analysis of the tap water. 6.4.2:Impact Assessment of the tap water and glass bottle water The comparison is made up of the environmental impact of glass bottled water and tap water. For the glass bottle water, the environmental impact is also determined by the power requirements, the basic infrastructure and in this case, the waste disposal scenario is taken into consideration which involves the recycling of the glass. The power requirements and basic infrastructures includes; Electricity, soda powder at the plant, natural gas, transport, manufacturing of the empty white glass bottle and assembly of glass bottle full of water. The analysis of the inventory carried out for the tap water shows that the environmental impact of tap water is determined by power requirements and by the basic infrastructure i.e. the electricity production medium, the pump station, portable water , water supply network and supply of water. By contrast, the recycling equipment used in water treatment is less relevant in this context. The power consumption figures (percentages) are relatively accurate as they make a 100%. Eco Eco-indicator 99 (l) V2.02/Europe El 99 l/l method was used in this study with regards to all the impact categories. For each of the two systems analysed using the SimaPro 7 LCA software, the potential contribution to climate change, ozone layer, Exotoxicity, acidification/eutrophication, respiratory organics, respiratory inorganics, radiation, carcinogens, land use and minerals are characterized. The results are presented below in histograms and in tables. Generally there are 3 steps in Life Cycle Inventory Analysis, namely: * Classification and characterization, * Normalization, and * Weighting Classification and characterization are mandatory element while normalization and weighting are optional elements (Guinee, 2002; Hauschild, Jeswiet, Alting, 2005; ISO14000, 2000). 6.4.3:Characterisation Chart 1:The characterisation under impact assessment for the life cycle analysis of the glass bottle. According to the characterisation chart above, the environmental impact is at the waste disposal scenario and assemble of glass bottle full of water but less at the transport process for all the impact categories. Table 4:Table showing the characterisation result of the impact category in glass bottled water Climate change Climate change is the change in the statistical distribution of weather over a period of time ranging from decades to millions of years. From chart 1 above, the main cause of climate change is more evident during the assembly of glass bottle full of water, emission of CO2, NOx, SO2 etc during the waste disposal stages and at the transport stage due to emission of CO2 by the lorry. These are indicated in table 4 above where they contributed 1.49E-9, -5.92E-8 and 1.31E-9 respectively. Ozone layer The ozone layer is a layer in Earths atmosphere containing relatively high concentrations of ozone (O3). This layer absorbs about 93-99% of the suns high frequency ultraviolet light, which is potentially damaging to life on earth. From chart 1 above, the main cause of the ozone layer is assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 3.71E-11, -7.45E-12 and 6.47E-13 respectively. Ecotoxicity Ecotoxicity refers to the potential for biological, chemical or physical stressors that affects the ecosystems. Such stressors might occur in the natural environment at concentrations, densities or levels high enough to disrupt the natural biochemistry, behaviour and interactions of the living organisms that comprise the ecosystem. From chart 1 above, the main cause of the ecotoxicity is assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 0.00779, -0.0171and 0.000516 respectively. Acidification/eutrophication Acidification is a natural process used to describe the loss of nutrient bases i.e. calcium, magnesium and potassium through the process of leaching and their replacement by acidic elements such as hydrogen and aluminium. Eutrophication is the increase in the concentration of chemical nutrients in an ecosystem to an level that it increases the primary productivity of the ecosystem. From chart 1 above, the main cause of the Acidification/eutrophication is assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 0.022, -0.00425 and 0.000211 respectively. Respiratory organics From chart 1 above, the main cause of the respiratory organics is assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 2.2E-10, -8.4E-11 and 2.02E-11 respectively. Respiratory inorganics From chart 1 above, the main cause of the respiratory inorganics is assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 3.57E-7, -1.56E-7 and 2.94E-9 respectively. Radiation Radiation is energy that travels in form of waves or high-speed particles. It occurs naturally in sunlight and sound waves. If exposed to small amounts of radiation over a long time, it increases the risk of cancer and it can also cause mutations in genes, which could be pass on to generations after exposure. From chart 1 above, the main cause of the radiation is the assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 1.11E-10,-1.25E-11 and 1.02E-12 respectively. Carcinogens A carcinogen is any substance or radiation, that is an agent directly involved in the exacerbation of cancer or in the increase of its propagation. From chart 1 above, the main cause of the carcinogen is the assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 1.99E-8,-1.03E-8 and 3.41E-10 respectively. Land use Land use is the modification of natural environment into built environment such as fields, pastures, and settlements. From chart 1 above, the major impact on land use is caused by the assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 0.00345,-0.00942 and 0.000176 respectively. Minerals Minerals are naturally occurring solid formed through geological processes with characteristic chemical compositions, highly ordered atomic structure, and specific physical properties. From chart 1 above, the major impact on mineral is caused by the assembly of the glass bottle full of water, emission during the waste disposal stage and the transportation stage. These are indicated in table 4 above where they contributed 0.00586,-0.00357 and 0.00034 respectively. NB: From the characterisation impact category, the negative number for the waste disposal stage is caused by the uptake of carbon from the atmosphere during the water disposal scenario. Chart 2:The characterisation under impact assessment for the life cycle analysis of the tap water. From the characterisation chart above, the environmental impact occurred at the supply of water stage for all the impact categories. Table 5:Table showing the characterisation result of the impact in the tap water 6.4.4:Normalization Normalization is defined as the extent to which an impact category contributes to the total environmental burden (Guinee, 2002). When the values are normalized, comparison between impacts can be made. From chart 3 below, It was found that the main impact is from the assembly of glass bottle full of water. The main substances that contributed to this impact are; Carbon dioxide, fossil, hydrogen chloride, hydrogen fluoride, lead, nitrogen oxides, particulates and sulphur oxide emissions that occurred during the manufacturing of the empty white glass bottle. The second impact is the waste disposal, this impact is caused during the waste scenario. The third impact being transport caused due to emission from the lorry taking the bottles to the retailer. Chart 3:The normalisation under impact assessment for the life cycle of glass bottled water Table 6: The normalisation under impact assessment for the glass bottled water. Chart 4: The normalisation under impact assessment for the life cycle of tap water From the chart 4 above, It was found that the main impact is from the supply of water. The main substances that contributed to this impact are aluminium, chloride and chlorine emissions that occurred during the production of the portable water. Table 7: The normalisation under impact assessment for the tap water 6.4.5:Weighting Weighting is a process by which indicators are aggregated into a single score. It makes use subjective weighting factors (Soares, Toffoletto, Deschenes, 2006). Based on table 7, the weighting under impact assessment for the life cycle of the glass bottled water is given the same as normalization. The main impact occurred at the assembly of glass bottle full of water. Followed by waste disposal and transport impact. Chart 5: The weighting under impact assessment for the life cycle of glass bottled water Table 8:The weighting under impact assessment for the glass bottled water Chart 6:The weighting under impact assessment for the life cycle of tap water Based on table 8 below, the weighting under impact assessment for the life cycle of the tap water is given the same as the normalization. The main impact from the supply of water. The main substances that contributed to this impact are aluminium, chloride and chlorine emissions that occurred during the production of the portable water. Table 9:The weighting under impact assessment for the tap water Conclusion / Recommendation From the analysis conducted, tap water contributed the least damage to the environment while glass bottle contributed the highest damage to this category. However, tap water still contributed even at a moderate effect and efforts are needed based on reducing the damages that could happen. Thus, from an environmental point of view, tap water is generally preferable to glass bottled water. If, as an exception, bottled water is consumed, its production process is much more relevant for its environmental impact than its assembly. Among the impacts identified are; * The empty glass bottles production process contributes damages to the human health and the ecosystem quality. * The electricity generation process which uses natural gas has reduced the natural resource. To overcome these problems, suggestions of corrections are as follows: 1. The use of plastic bottles water to replace the glass bottle water 2. The reliance on natural gas for electricity generation is suggested to be combined with other two types of renewable electricity generation namely: * Using 25% solar energy (considering most manufacturing industries to divert into the use of solar energy). * Using 25% hydro-electric energy 25% considering the fact that electricity could be generated from the flowing water in the water treatment plant. * Using 50% natural gas. 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National Pollution Prevention Center, School of Natural Resources and Environment, University of Michigan, Dana Building, 430 E. University, Ann Arbor, MI 48109-1115, USA Lopes. E and Dias. A et al (2002) Application of life cycle assessment to the Portuguese pulp and paper industry. Department of Environment and Planning, University of Aveiro, 3810 Aveiro, Portugal, Journal of Cleaner Production 11 (2003) 51-59. Medline Plus website (2010) Radiation Exposure [online] Available from: http://www.nlm.nih.gov/medlineplus/radiationexposure.html [Accessed 12th April 2010] Patterson. T (2009) LIFE CYCLE ASSESSMENT (LCA). Sustainable Environment research centre, University of Glamorgan.

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