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Environmental Sustainability Normalization of Industrial Processes
19th European Symposium on Computer Aided Process Engineering – ESCAPE19 J. JeĪowski and J. Thullie (Editors) © 2009 Elsevier B.V. All rights reserved.
1105
Environmental Sustainability Normalization of Industrial Processes Ángel Irabien,a Rubén Aldaco,a Antonio Dominguez-Ramosa a
Universidad de Cantabria, Ingenieria Quimica y Quimica Inorgánica, Avda de los Castros s/n, Santander, 39005, Spain, E-mail:[email protected]
Abstract Sustainability indexes or indicators may be considered objective functions for industrial processes. They are based on different considerations; AIChE sustainability index [1] is based on seven components: Environmental Performance, Safety Performance, Product Stewardship, Social Responsibility, Value-Chain Management, Strategic Commitment and Sustainability Innovation; the Sustainable Development Progress Metrics developed by IChemE is based on three components: Environmental indicators, Economic indicators and Social indicators [2], but in all cases environmental variables play an important role in the sustainability evaluation. The Environmental Sustainability is based on two different variables: (1) Natural Resources Sustainability (NRS), and (2) Environmental Burdens Sustainability (EBS). The main components of EBS have been classified as atmospheric pollutants, water pollutants, soil pollutants and a fourth group including specific environmental burdens such as noise, etc. In this work normalization procedures for the environmental sustainability will be developed in order to get suitable objective functions for process optimization. Keywords: Normalization, Sustainability, Environmental impacts, LCA, Environmental Burdens
1. Introduction The competition on the chemical market has increased during the past decades and among the problems that the chemical and process industry has to face, the following can be mentioned: a) Many chemical plants for the production of bulk products were built based on a large margin of benefits; b) The globalization results in a great competitive pressure, on the operating companies. c) E-commerce based on the globalization leads to an increasing efficiency in the world market. Therefore, to be still competitive, most existing production processes need constant improvement through retrofitting while new processes need to satisfy stricter governmental regulations with concerns to pollution and social demands based on Corporate Social Responsibility (CSR). CSR (also called corporate responsibility, corporate citizenship, responsible business and corporate social opportunity) is a concept whereby organizations consider the interests of society by taking responsibility for the impact of their activities on customers, suppliers, employees, shareholders, communities and other stakeholders, as well as the environment.
1106
Á . Irabien et al.
One of the main challenges related to the environmental sustainability evaluation of industrial processes lies on the quantitative estimation of the environmental burdens, the normalization procedures and the impact evaluation. In order to compare results of different alternatives Life Cycle Assessment (LCA) has been assumed as the main technique, but it is very difficult to find normalization procedures to evaluate and compare different environmental impacts. Taking into account the Integrated Pollution Prevention Control (IPPC) policy [3] and the Integrated Product Policy (IPP) developed in the European Union, which includes a public information system based on the European Pollutants Release and TransferRegister (EPRT-R) [4] an initial classification and quantitative technical evaluation of the pollutants of concern has been considered for normalization purposes. Following these references; as first step a general normalized multi-objective function based on atmospheric pollutants, water pollutants, soil pollutants and transferred pollutants can be defined for environmental sustainability evaluation of the industrial chemical processes, which can be used for global LCA [5]. Increasing productivity based on the reduction of materials, water and energy consumption, leading to decrease the emissions the effluents and the industrial wastes all represent conditions (or constraints), which can be formulated as mathematical optimization problems. They also, formulate the conditions for a more sustainable process, which has been formulated for chemical transformations [6]. For many complex processing-systems, the techniques needed to solve these optimization problems may be time consuming or may even fail to give a solution. Also, for large and complex applications to chemical or biochemical processes, even when the problem is well defined and is solvable, there is no guarantee that the solution is the global optimum. Usually, the obtained solution is a trade-off between many of the above contradictory constraints (or conditions) as they may point towards opposite directions with respect to the performance criteria. The objective of this paper is to present a new generic and systematic methodology based on the European IPPC and IPP criteria in order to develop an objective function allowing the normalization procedure to different environmental constraints, related to the environmental sustainability.
2. Environmental Sustainability Variables Environmental Protection Agencies have been able to develop evaluation procedures, for example US EPA as part of their WAR algorithm [7]. The Institution of Chemical Engineers-UK has introduced for chemical process industries, the sustainability metrics to help engineers to address the issue of sustainable development. They also enable manufacturing companies to set targets and to monitor progress on a yearly basis. A lower metric indicates that either the impact of the process is less or the output of the process is more. In this work, the environmental sustainability metrics as proposed by the IChemE has been employed. From an environmental sustainability evaluation point of view, two main variables: X1, Natural Resources Sustainability (NRS) and X2, Environmental Burdens Sustainability (EBS) has been selected. These metrics should give a balanced view of the environmental impact of inputs– resource usage, and outputs– emissions, effluents and wastes and the products and services produced. Natural Resources Sustainability is based on the evaluation of four main variables: X1,1 Energy, X1,2 Material (excluding fuel and water), X1,3 Water, and X1,4 Land. These variables are related to economical considerations depending on the different markets.
Environmental Sustainability Normalization of Industrial Processes
1107
Environmental Burdens Sustainability, X2 is a very complex variable because an important number of chemical substances need to be taken into account. From a technical point of view: emissions, effluents and wastes have to be considered. The environmental impact categories chosen are a sub-set of those used internationally in environmental management, selected to focus on areas where the process industry’s activities are most significant. The environmental burden approach is a scientifically sound way to quantify environmental performance. It draws on developments in environmental science to estimate potential environmental impact, rather than merely stating quantities of material discharged. The Environmental Burden (EB) caused by the emission of a range of substances, is calculated by adding up the weighted emission of each substance. The weighting factor is known as the “potency factor”:
EBi = ¦WN ·PFi , N
(1)
where EBi = ith environmental burden, WN = weight of substance N emitted, including accidental and unintentional emissions, PFi,N = potency factor of substance N for ith environmental burden. Related to these variables an atmospheric impact X2,1 based on the emissions, an aquatic impact X2,2 based on the effluents and a land impact X2,3 based on the wastes can be assumed. The atmospheric impact can be related to five main environmental impacts: X2,1,1 Atmospheric acidification. EB is te/y sulphur dioxide equivalent; X2,1,2 Global warming. EB is te/y carbon dioxide equivalent; X2,1,3 Human health (carcinogenic) effects. EB is te/y benzene equivalent; X2,1,4 Stratospheric ozone depletion. EB is te/y CFC-11 equivalent; X2,1,5 Photochemical ozone (smog) formation. EB is te/y ethylene equivalent. The aquatic impact can be related to four environmental impacts: X2,2,1 Aquatic acidification. EB is te/y of released H+ ions; X2,2,2 Aquatic oxygen demand. EB is te/y oxygen; X2,2,3 Ecotoxity to aquatic life. EB is (i) X2,2,3,1 te/y copper equivalent, and (ii) X2,2,3,2 te/y formaldehyde equivalent; X2,2,4 Eutrophication. EB is te/y phosphate equivalent. The impacts to land can be described by: X2,3,1 Total Hazardous Solid Waste Disposal (where fourteen different hazardous characteristics, H1…H14 need to be considered) and X2,3,2 Total Non-Hazardous Solid Waste Disposal. 2.1. Normalization Procedure The E-PRTR Regulation [8] establishes an integrated pollutant release and transfer register at Community level in the form of a publicly accessible electronic database. It lays down rules for its functioning, in order to implement the UN-ECE Protocol on Pollutant Release and Transfer Registers and facilitate public participation in environmental decision making, as well as contributing to the prevention and reduction of pollution of the environment. The E-PRTR Regulation includes specific information on releases of pollutants to air, water and land and off-site transfers of waste and of pollutants in wastewater. Those data have to be reported by operators of facilities carrying out specific activities. Annex II of the E-PRTR Regulation lists the 91 pollutants that are relevant for reporting under the E-PRTR. Annex II to the E-PRTR Regulation also specifies for each pollutant an annual threshold value for releases to each relevant medium (air, water, land). The threshold values for releases to water also apply in respect of the off-site transfer of pollutants in wastewater destined for treatment. Where no threshold value is given, the parameter and medium in question do not trigger a reporting requirement.
1108
Á . Irabien et al. Table 1. Normalization procedure. Atmosphere
Variable
Reference
Number of substances [2]
X2,1,1
te/y dioxide te/y carbon dioxide te/y benzene te/y CFC-11 te/y ethylene
6
X2,1,2 X2,1,3 X2,2,4 X2,1,5
Reporting Dimensionless threshold (kg) variable [8] sulphur 150,000 X2,1,1 / 150 100,000,000
X2,1,2 / 100,000
23
1,000 1 1,000
X2,1,3 / 1 X2,1,4 / 0.001 X2,1,5 / 1
52 60 100
Table 1 shows the reduction of complexity in the environmental sustainability evaluation: near 250 different substances have been considered in the emissions to the atmosphere, which have been reduced to five dimensionless variables, which can be weighted in a standard indicator for atmospheric impact assessment: X2,1. Table 2. Normalization procedure. Aquatic Impact
Variable
X2,2,1 X2,2,2 X2,2,3
X2,2,4
Reference
Reporting Dimensionless threshold (kg) variable [8] X2,2,1 / 0,1 te/y of released 100 H+ ions te/y oxygen 50,000 X2,2,2 / 50 X2,2,3,1 te/y 50 X2,2,3 / 0,05 copper te/y 50 X2,2,3,2 formaldehyde te/y phosphate 5,000 X2,2,4 / 5
Number of substances [2] 4 14 11 18 8
Table 2 shows the main aquatic impacts, which can be also reduced to a weighted standard indicator X2,2. Table 3. Normalization procedure. Land Impact
Variable
Reference
X2,3,1
Hazardous Solid Waste Non-Hazardous 2,000 t/year Solid Waste
X2,3,2
Reporting threshold (t) [8] 2 t/year
Dimensionless variable X2,3,1 / 2
Number of substances [2] H1………H14
X2,3,2 / 2,000
Waste transfer is related to the hazardous properties H1…..H14, according to these considerations land impact can be evaluated by a weighted standard indicator X2,3, Table 3.
Environmental Sustainability Normalization of Industrial Processes
1109
3. Conclusions Environmental sustainability in industrial processes is a multiobjective optimization procedure due to the influence of the site location connected to the environmental vulnerability. It corresponds to a complex system optimization due to the increasing number of substances, which need to be controlled. In this paper a systematic normalization procedure has been developed based on the considerations of the European Integrated Pollution Prevention Policy (IPPC). Some examples will be given as case studies corresponding to the application of this methodology to the process optimization.
4. Acknowledgements This research was funded by the Spanish Ministry of Science and Technology (Project C- CTM2006-00317).
5. References [1] D Schuster, "Benchmarking Sustainability", Chemical Engineering Progress, Vol. 103, No. 6, June 2007. [2] Institution of Chemical Engineers, "The Sustainability Metrics. Institution of Chemical Engineers Sustainable Development Progress Metrics recommended for use in the Process Industries"Institution of Chemical Engineers, 2002. [3] Official Journal of the European Union L 24, "Directive 2008/1/EC of the European Parliament and of the Council of 15 Jan. 2008. concerning integrated pollution prevention and control (Codified version)", Jan. 2008. [4] Official Journal of the European Union L 33. "Regulation (EC) No 166/2006", Feb. 2006. [5] I. Grossmann, "Challenges in the new millenium: product discovery and design,enterprise and supply chain optimization, global life global life cycle assessment", Computers and Chemical Engineering, Vol. 29, pp29–39, Jul. 2004. [6] Anastas, P. T., Lankey, R. L., “Sustainability through green chemistry and engineering”, ACS Symposium Series, 823: 1-11, 2002. [7] Young, D., Scharp, R., Cabezas, H., “The Waste Reduction (WAR) Algorithm: Environmental Impacts, Energy Consumption and Engineering Economics”, Waste Management, 20: 605-615, 2000. [8] E-PRTR Regulation: Regulation (EC) No 166/2006 of the European Parliament and of the Council concerning the establishment of a European Pollutant Release and Transfer Register and amending Council Directives 91/689/EEC and 96/61/EC.
1105
Environmental Sustainability Normalization of Industrial Processes Ángel Irabien,a Rubén Aldaco,a Antonio Dominguez-Ramosa a
Universidad de Cantabria, Ingenieria Quimica y Quimica Inorgánica, Avda de los Castros s/n, Santander, 39005, Spain, E-mail:[email protected]
Abstract Sustainability indexes or indicators may be considered objective functions for industrial processes. They are based on different considerations; AIChE sustainability index [1] is based on seven components: Environmental Performance, Safety Performance, Product Stewardship, Social Responsibility, Value-Chain Management, Strategic Commitment and Sustainability Innovation; the Sustainable Development Progress Metrics developed by IChemE is based on three components: Environmental indicators, Economic indicators and Social indicators [2], but in all cases environmental variables play an important role in the sustainability evaluation. The Environmental Sustainability is based on two different variables: (1) Natural Resources Sustainability (NRS), and (2) Environmental Burdens Sustainability (EBS). The main components of EBS have been classified as atmospheric pollutants, water pollutants, soil pollutants and a fourth group including specific environmental burdens such as noise, etc. In this work normalization procedures for the environmental sustainability will be developed in order to get suitable objective functions for process optimization. Keywords: Normalization, Sustainability, Environmental impacts, LCA, Environmental Burdens
1. Introduction The competition on the chemical market has increased during the past decades and among the problems that the chemical and process industry has to face, the following can be mentioned: a) Many chemical plants for the production of bulk products were built based on a large margin of benefits; b) The globalization results in a great competitive pressure, on the operating companies. c) E-commerce based on the globalization leads to an increasing efficiency in the world market. Therefore, to be still competitive, most existing production processes need constant improvement through retrofitting while new processes need to satisfy stricter governmental regulations with concerns to pollution and social demands based on Corporate Social Responsibility (CSR). CSR (also called corporate responsibility, corporate citizenship, responsible business and corporate social opportunity) is a concept whereby organizations consider the interests of society by taking responsibility for the impact of their activities on customers, suppliers, employees, shareholders, communities and other stakeholders, as well as the environment.
1106
Á . Irabien et al.
One of the main challenges related to the environmental sustainability evaluation of industrial processes lies on the quantitative estimation of the environmental burdens, the normalization procedures and the impact evaluation. In order to compare results of different alternatives Life Cycle Assessment (LCA) has been assumed as the main technique, but it is very difficult to find normalization procedures to evaluate and compare different environmental impacts. Taking into account the Integrated Pollution Prevention Control (IPPC) policy [3] and the Integrated Product Policy (IPP) developed in the European Union, which includes a public information system based on the European Pollutants Release and TransferRegister (EPRT-R) [4] an initial classification and quantitative technical evaluation of the pollutants of concern has been considered for normalization purposes. Following these references; as first step a general normalized multi-objective function based on atmospheric pollutants, water pollutants, soil pollutants and transferred pollutants can be defined for environmental sustainability evaluation of the industrial chemical processes, which can be used for global LCA [5]. Increasing productivity based on the reduction of materials, water and energy consumption, leading to decrease the emissions the effluents and the industrial wastes all represent conditions (or constraints), which can be formulated as mathematical optimization problems. They also, formulate the conditions for a more sustainable process, which has been formulated for chemical transformations [6]. For many complex processing-systems, the techniques needed to solve these optimization problems may be time consuming or may even fail to give a solution. Also, for large and complex applications to chemical or biochemical processes, even when the problem is well defined and is solvable, there is no guarantee that the solution is the global optimum. Usually, the obtained solution is a trade-off between many of the above contradictory constraints (or conditions) as they may point towards opposite directions with respect to the performance criteria. The objective of this paper is to present a new generic and systematic methodology based on the European IPPC and IPP criteria in order to develop an objective function allowing the normalization procedure to different environmental constraints, related to the environmental sustainability.
2. Environmental Sustainability Variables Environmental Protection Agencies have been able to develop evaluation procedures, for example US EPA as part of their WAR algorithm [7]. The Institution of Chemical Engineers-UK has introduced for chemical process industries, the sustainability metrics to help engineers to address the issue of sustainable development. They also enable manufacturing companies to set targets and to monitor progress on a yearly basis. A lower metric indicates that either the impact of the process is less or the output of the process is more. In this work, the environmental sustainability metrics as proposed by the IChemE has been employed. From an environmental sustainability evaluation point of view, two main variables: X1, Natural Resources Sustainability (NRS) and X2, Environmental Burdens Sustainability (EBS) has been selected. These metrics should give a balanced view of the environmental impact of inputs– resource usage, and outputs– emissions, effluents and wastes and the products and services produced. Natural Resources Sustainability is based on the evaluation of four main variables: X1,1 Energy, X1,2 Material (excluding fuel and water), X1,3 Water, and X1,4 Land. These variables are related to economical considerations depending on the different markets.
Environmental Sustainability Normalization of Industrial Processes
1107
Environmental Burdens Sustainability, X2 is a very complex variable because an important number of chemical substances need to be taken into account. From a technical point of view: emissions, effluents and wastes have to be considered. The environmental impact categories chosen are a sub-set of those used internationally in environmental management, selected to focus on areas where the process industry’s activities are most significant. The environmental burden approach is a scientifically sound way to quantify environmental performance. It draws on developments in environmental science to estimate potential environmental impact, rather than merely stating quantities of material discharged. The Environmental Burden (EB) caused by the emission of a range of substances, is calculated by adding up the weighted emission of each substance. The weighting factor is known as the “potency factor”:
EBi = ¦WN ·PFi , N
(1)
where EBi = ith environmental burden, WN = weight of substance N emitted, including accidental and unintentional emissions, PFi,N = potency factor of substance N for ith environmental burden. Related to these variables an atmospheric impact X2,1 based on the emissions, an aquatic impact X2,2 based on the effluents and a land impact X2,3 based on the wastes can be assumed. The atmospheric impact can be related to five main environmental impacts: X2,1,1 Atmospheric acidification. EB is te/y sulphur dioxide equivalent; X2,1,2 Global warming. EB is te/y carbon dioxide equivalent; X2,1,3 Human health (carcinogenic) effects. EB is te/y benzene equivalent; X2,1,4 Stratospheric ozone depletion. EB is te/y CFC-11 equivalent; X2,1,5 Photochemical ozone (smog) formation. EB is te/y ethylene equivalent. The aquatic impact can be related to four environmental impacts: X2,2,1 Aquatic acidification. EB is te/y of released H+ ions; X2,2,2 Aquatic oxygen demand. EB is te/y oxygen; X2,2,3 Ecotoxity to aquatic life. EB is (i) X2,2,3,1 te/y copper equivalent, and (ii) X2,2,3,2 te/y formaldehyde equivalent; X2,2,4 Eutrophication. EB is te/y phosphate equivalent. The impacts to land can be described by: X2,3,1 Total Hazardous Solid Waste Disposal (where fourteen different hazardous characteristics, H1…H14 need to be considered) and X2,3,2 Total Non-Hazardous Solid Waste Disposal. 2.1. Normalization Procedure The E-PRTR Regulation [8] establishes an integrated pollutant release and transfer register at Community level in the form of a publicly accessible electronic database. It lays down rules for its functioning, in order to implement the UN-ECE Protocol on Pollutant Release and Transfer Registers and facilitate public participation in environmental decision making, as well as contributing to the prevention and reduction of pollution of the environment. The E-PRTR Regulation includes specific information on releases of pollutants to air, water and land and off-site transfers of waste and of pollutants in wastewater. Those data have to be reported by operators of facilities carrying out specific activities. Annex II of the E-PRTR Regulation lists the 91 pollutants that are relevant for reporting under the E-PRTR. Annex II to the E-PRTR Regulation also specifies for each pollutant an annual threshold value for releases to each relevant medium (air, water, land). The threshold values for releases to water also apply in respect of the off-site transfer of pollutants in wastewater destined for treatment. Where no threshold value is given, the parameter and medium in question do not trigger a reporting requirement.
1108
Á . Irabien et al. Table 1. Normalization procedure. Atmosphere
Variable
Reference
Number of substances [2]
X2,1,1
te/y dioxide te/y carbon dioxide te/y benzene te/y CFC-11 te/y ethylene
6
X2,1,2 X2,1,3 X2,2,4 X2,1,5
Reporting Dimensionless threshold (kg) variable [8] sulphur 150,000 X2,1,1 / 150 100,000,000
X2,1,2 / 100,000
23
1,000 1 1,000
X2,1,3 / 1 X2,1,4 / 0.001 X2,1,5 / 1
52 60 100
Table 1 shows the reduction of complexity in the environmental sustainability evaluation: near 250 different substances have been considered in the emissions to the atmosphere, which have been reduced to five dimensionless variables, which can be weighted in a standard indicator for atmospheric impact assessment: X2,1. Table 2. Normalization procedure. Aquatic Impact
Variable
X2,2,1 X2,2,2 X2,2,3
X2,2,4
Reference
Reporting Dimensionless threshold (kg) variable [8] X2,2,1 / 0,1 te/y of released 100 H+ ions te/y oxygen 50,000 X2,2,2 / 50 X2,2,3,1 te/y 50 X2,2,3 / 0,05 copper te/y 50 X2,2,3,2 formaldehyde te/y phosphate 5,000 X2,2,4 / 5
Number of substances [2] 4 14 11 18 8
Table 2 shows the main aquatic impacts, which can be also reduced to a weighted standard indicator X2,2. Table 3. Normalization procedure. Land Impact
Variable
Reference
X2,3,1
Hazardous Solid Waste Non-Hazardous 2,000 t/year Solid Waste
X2,3,2
Reporting threshold (t) [8] 2 t/year
Dimensionless variable X2,3,1 / 2
Number of substances [2] H1………H14
X2,3,2 / 2,000
Waste transfer is related to the hazardous properties H1…..H14, according to these considerations land impact can be evaluated by a weighted standard indicator X2,3, Table 3.
Environmental Sustainability Normalization of Industrial Processes
1109
3. Conclusions Environmental sustainability in industrial processes is a multiobjective optimization procedure due to the influence of the site location connected to the environmental vulnerability. It corresponds to a complex system optimization due to the increasing number of substances, which need to be controlled. In this paper a systematic normalization procedure has been developed based on the considerations of the European Integrated Pollution Prevention Policy (IPPC). Some examples will be given as case studies corresponding to the application of this methodology to the process optimization.
4. Acknowledgements This research was funded by the Spanish Ministry of Science and Technology (Project C- CTM2006-00317).
5. References [1] D Schuster, "Benchmarking Sustainability", Chemical Engineering Progress, Vol. 103, No. 6, June 2007. [2] Institution of Chemical Engineers, "The Sustainability Metrics. Institution of Chemical Engineers Sustainable Development Progress Metrics recommended for use in the Process Industries"Institution of Chemical Engineers, 2002. [3] Official Journal of the European Union L 24, "Directive 2008/1/EC of the European Parliament and of the Council of 15 Jan. 2008. concerning integrated pollution prevention and control (Codified version)", Jan. 2008. [4] Official Journal of the European Union L 33. "Regulation (EC) No 166/2006", Feb. 2006. [5] I. Grossmann, "Challenges in the new millenium: product discovery and design,enterprise and supply chain optimization, global life global life cycle assessment", Computers and Chemical Engineering, Vol. 29, pp29–39, Jul. 2004. [6] Anastas, P. T., Lankey, R. L., “Sustainability through green chemistry and engineering”, ACS Symposium Series, 823: 1-11, 2002. [7] Young, D., Scharp, R., Cabezas, H., “The Waste Reduction (WAR) Algorithm: Environmental Impacts, Energy Consumption and Engineering Economics”, Waste Management, 20: 605-615, 2000. [8] E-PRTR Regulation: Regulation (EC) No 166/2006 of the European Parliament and of the Council concerning the establishment of a European Pollutant Release and Transfer Register and amending Council Directives 91/689/EEC and 96/61/EC.