Outline. MSW policy framework proposed by HKSAR. MSW management scenario in Hong Kong. Background. Methodology. Results and Discussion.

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1 Outline Background The Hong Kong Institution of Engineers A Life Cycle Eco-efficiency Analysis of the Proposed Landfill Extension and Advanced Incineration Facility in Hong Kong Dr. Vincent K. S. WOON Department of Civil and Environmental Engineering The 25 August 2015 Methodology Results and Discussion Conclusions Limitations and Recommendations 1 MSW management scenario in Hong Kong Hong Kong's three strategic landfills are: The West New Territories (WENT) Landfill at Tuen Mun (110 hectares) The South-East New Territories (SENT) Landfill at Tseung Kwan O (100 hectares) The North-East New Territories (NENT) Landfill at Ta Kwu Ling (61 hectares) Hong Kong rely solely on landfills to meet waste disposal needs 9,000 tonnes per day of MSW disposed of at the landfills estimated to be full by MSW policy framework proposed by HKSAR Landfill extension (LFE) IWMF - Advanced incineration facility (AIF) Recently approved by the Legislative Council Finance Committee and will be implemented in Hong Kong Locations of Strategic Landfills in Hong Kong Source: HKEPD, IWMF: Integrated Waste Management Facility 4

2 A hot debated issue Sustainability issue of proposed LFE and AIF Landfill Extension Environmental impacts Economic aspects Advanced Incineration Facility Human health Ecosystem quality Private cost External cost 5 Integration of LCA and LCC results LCA LCC Effective and scientific way for communicating the environmental and economic aspects simultaneously (Hong et al., 2010; Franchetti, 2013) Life Cycle Assessment (LCA) 6 Recent LCA and LCC studies Life Cycle Assessment (LCA) LCA studies on landfill and incineration (Hong et al., 2010; Koci and Trecakova, 2011; Menikpura et al., 2012) Life Cycle Costing (LCC) Environmental impacts contributed by the individual sub-process Hotspot that provides most environmental burden can be identified facilitate improvements on the operating and design criteria Eco-efficiency (WBCSD, 2000) Modified Eco-efficiency Indicator Link economic performance with its environmental impact using an ecoefficiency indicator (Shonnard et al., 2003) Limitation: normalization issue - difficult to be applied to impacts such as human health (require regional or country specific normalized values) Life Cycle Costing (LCC) LCC studies considered only private costs (Aye and Widjaya, 2006; Zhao et al., 2011; Assamoi and Lawryshyn, 2012) External costs are not evaluated to any depth External cost is important for public properties (e.g., waste disposal facility) avoid the free-ridership problem (Ertan et al., 2009) 7 8

3 Objectives To evaluate the environmental impacts of the proposed LFE and AIF using LCA methodology and identify the emission compounds and hotspot areas To investigate the life cycle costs of the proposed LFE and AIF via LCC methodology To develop a modified eco-efficiency indicator for determining the ecoefficiency of the proposed LFE and AIF Outline Background Methodology Results and Discussion Conclusions Limitations and Recommendations Additional dimension for formulating a MSW policy framework 9 Overview of methodology Part 1 Life cycle environmental impacts and hotspot analysis of proposed LFE and AIF Part 2 Life cycle costing and eco-efficiency of proposed LFE and AIF Life cycle assessment (LCA) LCA is a technique assessing the potential environmental aspects associated with a product or process throughout its life cycle. (ISO14040, 2006) Climate change Carcinogens Respiratory organics Respiratory inorganics Acidification/ Eutrophication 1. Goal and scope definition 2. Inventory analysis (LCI) 1 3. Impact assessment (LCIA) 2 Note: Ecotoxicity 1) LCI Life Cycle Inventory 2) LCIA Life Cycle Impact Assessment 12 Goal: objective of the study Scope: system boundary, functional unit 4. Interpretation

4 Subject of study, system boundary and functional unit Landfill Extension (LFE) WENT Landfill Extension Largest proposed waste capacity (81Mm 3 ) Current WENT landfill receives highest MSW disposal rate Advanced Incineration Facility (AIF) AIF to be located at an artificial land near Shek Kwu Chau Island Proposed first phase development System boundary: MSW hauling to energy recovery system in proposed waste disposal facilities Functional unit: per tonne of MSW (wet basis) Part 1: Major sub-processes of LFE Landfill Extension (LFE) (i) (ii) MSW transport from RTS to landfill Biological reactions at landfill cells (iii) Flare system (iv) Leachate collection and treatment system (v) Ash disposal after sludge treatment (vi) Energy recovery system electricity and heat generation 13 Part 1: Major sub-processes of AIF 14 Part 1: Data collection WENT = West New Territories APC = air pollution control Advanced Incineration Facility (AIF) (i) MSW transport from RTS to AIF + ash transport from AIF to landfill (ii) Stack discharge system (iii) Desalination system (iv) Ash treatment and disposal system (v) Energy recovery system electricity generation Hong Kong data are used whenever possible. Data Physical and elementary composition of MSW (e.g., waste composition, dry matter and carbon content of waste component) Emission compounds (e.g., heavy metals, dioxins, furans, benzene, SO 2, NO x, etc.) Consumption of heat/electricity of LFE and AIF, efficiency of gas and steam turbine Electricity emission factor Sources HKEPD waste statistic report for monitoring of solid waste and unpublished report EIA studies of Hong Kong WENT landfill extension and Integrated Waste Management Facilities (IWMF) Applications of Renewable Energy in Hong Kong. Stage 1 Study Report. Electrical and Mechanical Services Department (EMSD) China Light & Power (CLP) Company (power plant company in Hong Kong) 15 16

5 Part 1: Major assumptions of this study Toxicity Characteristics Leaching Procedure (TCLP) limits - incinerated ash being dumped in the landfills (5% leached into the groundwater) assume worst case scenario not reflect the actual potential situation for leaching Control value limits for air emission (i.e., Hong Kong Target s Emission Levels) - stack discharge system in the proposed AIF assume worst case scenario 87 waste-to-energy plants in the United States (Kaplan et al., 2009) actual emissions are less than regulatory requirements Part 1: Life cycle impact assessment SimaPro software with Eco-Indicator 99 (E) impact assessment method most widely used software for LCA studies on waste management sector (Kulczycka et al., 2015) Climate change Carcinogens Respiratory inorganics Respiratory organics Damage category - Human health 17 Part 1: Life cycle impact assessment (cont.) Unit: Disability Adjusted Life Year () Provide a comparison among the selected impact categories Adopted by World Heath Organization (WHO) and World Bank in the field of public health and health impact assessment Cumulative number of years lost due to disease, injury or early death Disability Adjusted Life Years () = Years lost due to disease or injury (morbidity) + Years of life lost (mortality) 18 Part 2: Life cycle costing Summary of private cost/benefit LCC Private costs and benefit: internal to the MSW disposal in LFE and AIF Private cost Private benefit Capital cost Transportation cost Operating cost Methodology for the systematic economic evaluation of life cycle costs over a period of analysis (ISO , 2008) Energy saving due to energy recovery system Healthy life Disease or injury Early death Mortality and morbidity are combined into a single, common unit. 19 Expected life years Most updated cost from reports of Legislative Council Finance Committee Avoided electricity/heat electricity tariff from China Light & Power (CLP) company and gas charge from Towngas company 20

6 Relative life cycle cost (%) Part 2: LCC - Summary of external cost/benefit External cost Opportunity cost of land Disamenity cost External environmental cost due to air pollution External cost/benefit Definition Quantification approach Opportunity cost of land Disamenity cost External environmental cost/benefit due to air pollution External benefit External environmental benefit due to air pollution A value of the land that must be given up to achieve another purpose of land use Nuisance caused due to noise, dust, odors, visual pollution Risks and benefits of air pollutants are quantified in monetary unit Sales comparison approach (SCA) Hedonic price model (HPM) Impact pathway analysis (IPA) Part 2: Integration of LCA and LCC Modified Eco-efficiency Indicator (EEI) Modified eco-efficiency indicator a two-dimensional graph to compare the relative importance of alternatives from environmental and economic perspectives of a waste disposal facility simultaneously Half non Ecoefficiency Half Ecoefficiency Fully non Eco-efficiency Fully Eco-efficiency Half non Ecoefficiency Half Ecoefficiency Relative life cycle environmental impact (%) System 1 System 2 Lower life cycle environmental impact, lower life cycle cost Outline Background Methodology Results and Discussion Conclusions Limitations and Recommendations Part 1 - Analyzing Environmental Hotspots of Proposed LFE and AIF in Hong Kong using LCA Environmental impacts of sub-processes of LFE and AIF Climate change Carcinogens Human Respiratory Organics Health Respiratory Inorganics 23 24

7 Impacts of sub-processes of landfill extension Impacts of sub-processes of landfill extension (cont.) 1.2E E E E E E E E E E E E E E E E E-08 Climate Change Carcinogens Respiratory Organics -8.0E-08 Respiratory Inorganics Climate change category mostly contributed by biological reactions at landfill cells (due to portion of uncollected landfill gas) but mostly offset by energy recovery system (displaced electricity supplied by CLP company) Carcinogens category Leachate collection and treatment system arsenic and cadmium leaching into the groundwater 25 Impacts of sub-processes of advanced incineration facility 1.0E E E E-07 Climate Change 6.0E E E-08 Carcinogens Climate change category mostly contributed by stack discharge system (release of CO 2 due to MSW combustion) but mostly offset by energy recovery system. Carcinogens category mostly constituted by ash treatment and disposal system (67.7% for whole category), and 32.3% from the stack discharge system. 27 Respiratory organics category Mainly contributed by flaring process, followed by leachate collection and treatment system attributed by the release of benzene to ambient air Respiratory inorganics category Flaring process but mostly offset by energy recovery system due to respiratory suspended particulates (RSP) displaced from the CLP company 26 AIF: Ash treatment and disposal system Carcinogens category AIF - ash treatment and disposal heavy metals arsenic and cadmium Suggestions reuse treated ash for civil application (e.g., road pavement) (Ferreira et al., 2003) reduce hazardous metals from entering AIF waste sorting and recycling (Tian et al., 2012) arsenic: circuit board, LCD displays, computer chips (e.g., Waste Electrical and Electronic Equipment (WEEE) Recycling Programme in 2005) cadmium: Ni-Cd battery (e.g., Rechargeable Battery Recycling Programme in 2005) 28

8 Relative Percentage (%) AIF: Emission compounds from stack discharge system Carcinogens category Ranking Emission compound Value ( 10-8 ) Percentage (%) 1 Cadmium Total heavy metals a Dioxins and furans a Including Sb, As, Pb, Co, Cr, Cu, Mn, V and Ni Dioxins and furans (from stack discharge system) insignificant burden (0.48% of the total impact for the stack discharge system) should not be a major public concern 29 Impacts of sub-processes of advanced incineration facility 5.0E E E E E-11 Respiratory Organics 2.0E E E E E-07 Respiratory Inorganics Respiratory organics category Mostly contributed by stack discharge system attributed by the release of volatile organic compounds Respiratory inorganics category Mostly contributed by stack discharge system attributed by the release of SO 2 and NO x Mostly avoided by energy recovery system due to RSP displaced from the CLP company 30 Overall impact and damage category Climate Change Carcinogens Respiratory Organics LFE Respiratory Inorganics AIF Human Health absolute value of waste disposal facility for an impact/damage category Relative percentage = 100% highest absolute value of waste disposal facility for that particular impact/damage category to show relative environmental burden between the LFE and AIF Climate change and respiratory inorganics: AIF is better than LFE Carcinogens and respiratory organics: LFE is better than AIF Human health: AIF is better than LFE Note: A positive percentage indicates a negative environmental performance 31 Part 2 - An Integrated LCC and Life Cycle Human Health Impact Analysis of LFE and AIF in Hong Kong via Modified Eco-efficiency Indicator Overall cost/benefit breakdown for LFE and AIF Results of modified eco-efficiency indicator 32

9 LCC - Overall cost/benefit breakdown Cost/benefit categories Landfill extension (LFE) Value (HK$/tonne MSW) Percentage (%) Advanced incineration facility (AIF) Value (HK$/tonne Percentage MSW) (%) Private cost Capital cost Transportation cost Operating cost External cost Opportunity cost of land Disamenity cost External environmental cost Total cost Private benefit Energy saving due to energy recovery system External benefit External environmental benefit Total benefit Total life cycle cost Private + external costs/benefits - AIF is slightly lower than LFE (163.2 HK$/tonne MSW) If only private cost/benefit - LFE is lower than AIF AIF higher capital cost LFE higher opportunity cost of land and disamenity cost (> households in Tuen Mun than Cheung Chau Island) Note: Positive value indicates a cost while negative value indicates a benefit 33 LCC - Overall cost/benefit breakdown (cont.) Cost/benefit categories Landfill extension (LFE) Value (HK$/tonne MSW) Percentage (%) Advanced incineration facility (AIF) Value (HK$/tonne Percentage MSW) (%) Private cost Capital cost Transportation cost Operating cost External cost Opportunity cost of land Disamenity cost External environmental cost Total cost Private benefit Energy saving due to energy recovery system External benefit External environmental benefit Total benefit Total life cycle cost Private and external benefits - AIF has higher benefits than LFE More energy recovered in AIF Replaces more electricity produced by the CLP company Offsets more air pollutants released from CLP company Note: Positive value indicates a cost while negative value indicates a benefit 34 Modified eco-efficiency indicator Outline Fully eco-efficiency Reference point: LFE AIF falls under the fully ecoefficiency part AIF has a lower LCA (with a focus on human health category) and a slightly lower life cycle cost than LFE. Background Methodology Results and Discussion Conclusions Limitations and Recommendations Note: All positive results indicate a worse situation than the reference; all negative results indicate better conditions than the reference

10 Conclusion - Part 1 Conclusion - Part 1 (cont.) Landfill Extension Environmental hotspots Climate change biological reactions at landfill cells Carcinogens leachate collection and treatment system Respiratory organics and respiratory inorganics flaring process Advanced Incineration Facility Reuse treated ash for civil application (e.g., road pavement) instead of landfill disposal of ash Environmental hotspots Climate change, respiratory organics, respiratory inorganics stack discharge system Carcinogens ash treatment and disposal system Increase waste sorting and recycling process to reduce hazardous metals from entering AIF 37 Conclusion - Part 1 (cont.) 38 Conclusion - Part 1 (cont.) Advanced Incineration Facility Insignificant burden to the carcinogens category Overall impact and damage category LCA vs. Dioxins Furans Should not be a major public concern Landfill Extension Carcinogens Respiratory organics Advanced Incineration Facility Climate change Respiratory inorganics 39 40

11 Conclusion Part 2 Conclusions Part 1 and Part 2 LCC vs. Landfill Extension Landfill Extension (LFE) Only private costs/benefit Modified EEI Advanced Incineration Facility (AIF) Private + external costs/benefits AIF is more eco-efficient than LFE Advanced Incineration Facility Serve as an additional view to the decision makers when determining the future management of MSW in Hong Kong 41 Outline Background Methodology Results and Discussion 42 Limitations and recommendations Waste reduction is not considered in the study total amount of MSW being disposed of at landfills was quite constant (~ 8,950 to 9,550 tpd) from 2004 to % MSW disposal rate reduction target of the per-capita daily MSW disposal rate by year 2022 Conclusions Limitations and Recommendations Deterministic values are used in the study uncertainty analysis to investigate the variability of the data and improve the reliability of the LCA and LCC results

12 Limitations and recommendations Life cycle evaluation from social aspect (e.g., provision for job opportunities, working conditions, citizen acceptance) Holistic view on the sustainable MSW management in Hong Kong 45 46