IMPLICATIONS OF RECYCLING ACTIVITIES ON SUSTAINABILITY OF SOLID WASTE MANAGEMENT IN THAILAND

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1 IMPLICATIONS OF RECYCLING ACTIVITIES ON SUSTAINABILITY OF SOLID WASTE MANAGEMENT IN THAILAND S.N.M. Menikpura, S. Bonnet, S.H. Gheewala * The Joint Graduate School of Energy and Environment, King Mongkut s University of Technology Thonburi, 126 Pracha-Uthit Road, Bangmod, Tungkru, Bangkok 10140, Thailand Corresponding author. Tel.: ; fax: address: shabbir_g@jgsee.kmutt.ac.th ABSTRACT At present, only 22% of Municipal Solid Waste (MSW) is being separated for recycling in Thailand while the rest is being open-dumped and landfilled. Such poor MSW management methods create severe environmental, economic and social problems. The development of a sustainable MSW management system is therefore, crucial and should be based on an integrated approach. The inclusion of recycling as one of the processes of an integrated MSW management system is necessary to ensure maximum reclamation of useful materials. Therefore, in this study, the environmental, economic and social implications of recycling activities as part of a MSW management system have been assessed for a particular municipality in Thailand using sustainability indicators. The evaluation results revealed that recycling can contribute bringing substantial socio-economic and environmental benefits when integrated as part of a MSW management system. Keywords: Municipal Solid Waste, Sustainability, Indicators, Recycling, Thailand Introduction Open dumping and non-engineered landfilling are the two predominant waste disposal methods used in most developing countries in Asia. Such poor MSW management methods create severe environmental, economic and social problems. Similar situations can be observed in Thailand. According to the Pollution Control Department (PCD), 22 % of generated MSW is being recycled in Thailand while the remaining fraction is being disposed in sanitary landfills and open dumps [1]. In this study, Nonthaburi municipality was selected to evaluate the implications of recycling activities on the sustainability of its MSW management system. Nonthaburi has put significant efforts in maximizing recycling and minimizing waste under the Kitakyushu Initiative Network Program via community approach, and public awareness and participation. As a result of this program, the recycling rate has increased from 22% in 2006 to almost 25% in Public participation and awareness raising campaigns were recognised as key factors for such successful achievements as well as the strong political will of the local administration [2]. Overview of recycling activities in Nonthaburi The municipality of Nonthaburi is located in the central region of Thailand and covers an area of 39 km 2 with a population of 0.27 million inhabitants [2]. The average amount of MSW generated in the municipality amounts to 370 tonnes per day, with a daily per capita MSW generation rate of 0.8 kg. Approximately 90 tonnes of recyclable waste are being separated at the household level and 38 small companies are involved in collecting those recyclables. The collected materials in the recyclable mix include five major categories which are paper, plastic, glass, aluminium and steel. These recyclables are pre-processed (cleaned, shredded and baled) at a sorting facility and then transported via heavy duty trucks to various recycling facilities in different provinces [2]. In this study, a detailed assessment was performed to evaluate the socio-economic and environmental implications of recycling as part of the MSW management system set in Nonthaburi. Methodology Life cycle assessment To evaluate the environmental, economic and social impacts related to recycling, Life Cycle Assessment (LCA) was used as the basic tool. To quantify the above mentioned impacts, the functional unit was defined as recycling of one tonne of waste in a recyclable mix. The system boundary includes raw material 176

2 extraction (crude oil extraction) and production of energy carriers (diesel production for transportation), collection and transportation of recyclables (by light duty trucks), pre-processing at the sorting facility (cleaning, size reduction, compaction and bailing), transportation of pre-processed recyclables to recycling facilities (by heavy duty trucks) and recycling processes. In addition, system expansion was used to account for material recovery. Thus, for instance, credits were provided to account for avoided virgin production of materials which had been recovered as a result of recycling. Inventory data was collected from individual recycling processes based on socio-economic and environmental considerations. Information related to material and energy consumptions, costs and revenues, as well as employment opportunities related to recycling processes were collected from various sorting plants and recycling facilities in Thailand. In addition, appropriate databases such as Ecoinvent and BUWAL 250) [3-4] were used to quantify life cycle emissions and resources consumption from recycling as well as virgin production processes. Indicators for sustainability assessment In order to assess the implications of recycling activities on sustainability, relevant socio-economic and environmental indicators were identified. According to the inventory data collected, it was found that recycling activities are associated with fossil energy consumption in the form of diesel fuel, electricity and thermal energy. This contributes to abiotic resources depletion and greenhouse gases (GHGs) emissions. In contrast, the materials recovered as a result of recycling enable to gain benefits from the avoided virgin production of such materials and related GHG emissions. In order to quantify the environmental impacts of recycling activities, global warming potential (GWP) and abiotic depletion potential (ADP) were therefore identified as the most relevant environmental indicators. To estimate GWP, the GHGs considered include carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) [5]. GWP is expressed in the unit of CO 2 equivalent. Fossil fuel and mineral resources consumption are characterised in terms of ADP which is expressed in the unit kg of antimony (Sb) equivalent. The sustainability of a MSW management system is influenced by its capital and operating costs. A detailed financial analysis via a Life Cycle Cost (LCC) is an appropriate option to deal with such an economic assessment [6-7]. Hence, LCC was selected as the economic indicator to perform the evaluation. The concept of community well-being is one factor considered for social sustainability assessment. Poverty alleviation and economic development are major aspects related to improvement of communities well-being. As recycling activities can contribute to uplifting living standards by facilitating employment and providing income generation opportunities, the income based community well-being was selected as the indicator for social impact assessment. Results and Discussion Composition of the Recyclable Mix in Nonthaburi The composition of the recyclable mix and the recyclability of the different materials it is composed of are important factors to assess the amount of materials that can be recovered from recycling. In Nonthaburi, the recyclable mix consists of five major categories that are paper, plastic, glass, aluminium and steel in the proportion of 23%, 3%, 7%, 27%, and 40% respectively. Based on the recyclability of those materials, from one tonne of paper, plastic, glass, aluminium and metal, 850 kg, 900kg, 950kg, 760kg and 900kg of recycled products can be recovered respectively [2, 3-4]. Environmental Sustainability Assessment From the inventory data collected, GWP and ADP were estimated as shown in Figure 1 (a) and (b). It is observed that in comparison to other recyclable materials, the benefits of aluminium recycling are outstanding for both the environmental impacts considered. Virgin aluminium production is responsible for higher GWP and ADP because of the large amount of fossil fuel consumption required for its production and related emissions. Thus, the credited impacts from recycling of aluminium influence considerably the reduction in net GWP and ADP values. The estimated net GWP and ADP from recycling of one tonne of recyclable mix amount to kg CO 2 equivalent and kg of Sb equivalent respectively. The 177

3 negative values obtained express the environmental benefits arising from recycling activities and therefore its advantage as an environmentally sustainable option for MSW management. (a) GWP (kg of CO2 eq/tonne) 1.40E E E E E E E E+00 Recycling Plastic Virgin production Recyclable mix (b) ADP (kg of Sb eq)/tonne 7.00E E E E E E E E+00 Recycling Virgin production Plastic Recyclable mix Figure 1. (a) GWP (b) ADP from recycling of waste materials and corresponding virgin production of such materials Economic Sustainability Assessment For the LCC assessment, all cost elements were identified in a systematic way including capital expenditure, operation and maintenance costs, and environmental cost (monetary value for the environmental emissions). To calculate the gross LCC for the recycling operations, cost at the sorting plant and cost at the recycling facility were added. From the results obtained it was observed that operation and maintenance costs share a major fraction of the gross LCC mainly because of the high labour, electricity and primary energy costs associated with recycling operations. In fact, operation and maintenance costs represent 86%, 65%, 59%, 93% and 75% of the gross LCC for paper, plastic, glass, aluminium and metal respectively. The selling price of all the primary products recycled and the monetary value of the credited environmental emissions were taken into account to calculate the revenues generated from recycling activities. For each category of recyclable materials, the net LCC was determined by subtracting revenues from the gross LCC as shown in Figure 2. It is observed from the above figure that revenues from recycling are much higher than gross LCC for all recyclable materials. The estimated net LCC was determined to amount to -11,700 baht/ tonne of waste for 178

4 the recyclable mix in Nonthaburi (30.8 baht = 1 US$) see Figure 2. The negative values obtained express the potential of net earnings from recycling. In fact, 1.02 million baht can be expected as net earnings from the daily amount of recyclable (90 tonnes) generated in Nonthaburi municipality. Such figures highlight the potential benefits offered by recycling activities as part of a MSW management system and how important it is to promote such activities as an economically attractive business. Cost & revenue (baht/tonne) 100,000 80,000 60,000 40,000 20, ,000-40,000 Gross LCC Revenue Net LCC Plastics Recyclable Mix Figure 2. Gross LCC, revenue and net LCC of recycling Social Sustainability Assessment At the community level, recycling was found to contribute income generation from the selling of recyclables as well as employment opportunities. Thus for instance, from the daily selling of recyclables (90 tonnes), the indirect income generation potential in the community was estimated at 1.57 million baht which corresponds to 17,440 baht/tonne. In addition, recycling activities were found to contribute to the creation of 675 skilled employment opportunities in the community at various positions from waste collectors to managing directors. The estimated total labour power (skilled and unskilled) requirement per tonne of recyclable mix works out to 7.5 labour days. Based on this, the average wage-based income generation potential for the community was estimated to amount to 2,900 baht/tonne of recyclable mix. From the above figures, total income generation potential amounts to 20,300 baht/tonne of recyclable mix. Such income generation provides direct benefits to the community in uplifting their living standards. Conclusions The Nonthaburi municipality in Thailand was identified as an interesting case study to assess the implications of recycling on the sustainability of its MSW management system since it has been involved in a program promoting such activities. For the assessment, relevant environmental, economic and social indicators were identified to quantify the ultimate effects of recycling. The results obtained clearly show that recycling offers important prospects since it provides non negligible socio-economic and environmental benefits and therefore contribute to improve sustainability of the entire MSW management system in place. The results of this study could be used as a probing tool to convince all stakeholders involved in waste management of the benefits of recycling and to promote and strengthen recycling activities in Thailand. Acknowledgements Research grant from The Joint Graduate School of Energy and Environment is acknowledged. The authors would like to also express their gratitude to the Nonthaburi Municipality and recycling facilities in Thailand for providing the necessary information and data to perform this study. 179

5 References [1] PCD Status of Municipal Solid Waste. The Pollution Control Department, Thailand. Available in [2] Nonthaburi Municipality Bangkrasor, Thailand (Personal communication). [3] Pre Consultants BUWAL 250, SimaPro 7.1 Manual. Amersfoort, Netherlands. [4] R. Hischierand and E.M.P.A St. Gallen Life cycle inventories of packaging and graphical papers. Eco-invent report no.11, Swiss Centre for Life Cycle Inventories, Dübendorf. [5] IPCC Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programme, Eggleston H.S., Buendia, L., Miwa, K., Ngara, T., Tanabe, K. (Eds.). Published: IGES, Japan. [6] J. Lutz, A. Lekov, P. Chan, C.D. Whitehead, S. Meyers and J. McMahon Life-cycle cost analysis of energy efficiency design options for residential furnaces and boilers. Energy, 31: [7] M. C. Reich Economic assessment of municipal waste management systems case studies using a combination of life cycle assessment (LCA) and life cycle costing (LCC). J of Clean Prod, 13: