大都市地区共享城市固体废物管理外文文献Economic analysis of a shared municipal solid waste management facility in a metropolitan region

Economic analysis of a shared municipal solid waste management facility in a metropolitan region Diogo Appel Colvero a b Jos Ramalhoc Ana Paula Duarte Gomesa Manuel Arlindo Amador de Matosa Lu s Ant nio da Cruz Tarelho a aDepartment of Environment and Planning and Centre for Environmental and Marine Studies University of Aveiro Portugal b Researcher of the Brazilian National Council for Scientifi c and Technological Development CNPq File No 207172 2014 5 Brazil cDepartment of Mechanical Engineering University of Aveiro Portugal a r t i c l ei n f o Article history Received 7 December 2018 Revised 30 October 2019 Accepted 21 November 2019 Available online 6 December 2019 Keywords Economic analysis Municipal solid waste MSW Shared management Tariff Brazil a b s t r a c t Municipal solid waste MSW management in dense urban areas is a challenge for municipalities espe cially in developing countries which commonly have defi cient waste management For example the metropolitan region of Goi s State Brazil has 19 municipalities that dispose of about 72 5 of total MSW in unlicensed MSW fi nal disposal facilities Therefore this study analysed the investment and oper ating costs and revenues of a municipal solid waste management facility projected for 20 years shared among these 19 municipalities The economic viability analysis has shown that regardless of the man agement facility type MSW collection and transport are the most expensive cost components accounting for about 60 of MSW management operating costs For an Internal Rate of Return of 0 anaerobic diges tion is 11 more expensive in total than using community composting For 2040 last year the monthly MSW management tariffs will vary between 3 5 and 10 8 R inhabitant 1 month 1 depending on the municipality So as the unit price of biowaste treatments lowers with waste quantities for the munici palities with large biowaste quantities anaerobic digestion becomes recommended for its economic attractiveness This study can serve as a model for other municipalities in Brazil and elsewhere helping public decision makers to establish a strategy for MSW management 2019 Elsevier Ltd All rights reserved 1 Introduction Currently municipal solid waste MSW management follows different paths in developed and developing countries In the fi rst case the MSW management model is focused on the hierarchy of waste management which consists of prevention reuse prepara tion for reuse recovery and disposal EU 2018 Otherwise for developing countries the MSW management model is generally insuffi cient with an incomplete waste collection coverage low source separation and recovery rates of such waste which ends up commingled and sent to landfi lls or dumps Figueiredo 2012 World Bank 2012 Therefore the world needs to pay attention to the increased production of MSW If not treated properly MSW can produce seri ous environmental damage Lavee and Nardiya 2013 and the loss of resources This is especially true in developing countries with large populations dense urban areas fast growth of per capita MSW generation and defi cient waste management Abramovay et al 2013 Bernstad Saraiva et al 2017 Brazil is an example of a developing country that presents defi cient MSW management According to ABRELPE 2017 78 3 mil liontonnesofMSWwereproducedin2016 Ofthese approximately 91 were collected while the remaining 9 were uncollected and dumped in vacant lots rivers on city streets or burned in the open Alfaia et al 2017 In Goi s State Brazil MSW management is defective because the practices based on prevention and circular economy are still nascent Colvero et al 2017b Consequently MSW is commingled and disposed of in dumps or unlicensed landfi lls Abreu et al 2016 Figueiredo 2012 This breaches Law No 12 305 2010 National Solid Waste Policy PNRS that stipulates that all Brazil ian municipalities should terminate any unsuitable MSW fi nal dis posal facilities by August 2014 Brasil 2010 In 19 municipalities located in the metropolitan region of Goi s near capital Goi nia 97 2 of all collected MSW is sent for fi nal disposal Of those 72 5 goes to dumps or unlicensed landfi lls and only 24 7 are sent to landfi lls licensed by the Environmental Water Resources Infrastructure Cities and Metropolitan Affairs https doi org 10 1016 j wasman 2019 11 033 0956 053X 2019 Elsevier Ltd All rights reserved Corresponding author at Campus Universit rio de Santiago 3810 193 Aveiro Portugal E mail address diogocolvero ua pt D A Colvero Waste Management 102 2020 823 837 Contents lists available at ScienceDirect Waste Management journal homepage Offi ce of Goi s SECIMA GO Colvero et al 2017b The other 2 0 are recycled and 0 8 are uncollected Supplementary Material SM Table 1 Similarly in the rest of Brazil MSW management is almost exclusively done in landfi lls Alfaia et al 2017 Likewise almost no actions are currently aimed at reducing waste produc tion in Brazil such as initiatives to encourage changes in people s consumption patterns or information about life cycle impacts and resource costs Brasil 2010 EC 2008 Godecke Naime Maier and Oliveira 2014 Pin et al 2018 Santos et al 2019 How ever few studies perform this type of evaluation in a holistic way discretizing all operations and processes associated with the man agement of MSW from the conception of the model until the end of the project life like this study does While this is a large innova tion this paper also presents an economic viability analysis of a MSWMF with two different alternatives the fi rst in which the facility is built by the State and the second in which a partnership between the State and the private sector is foreseen Furthermore the research is intended to assist the decision makers of these municipalities and Goi s State in developing a strategic plan to meet the recommended landfi ll diversion targets for Brazil 2 Materials and methods The proposed MSWMF covers 19 municipalities located in Goi s State Midwest Brazil that are highly heterogeneous in pop ulation density and MSW production In 2015 they accounted for 35 of the total population of Goi s and produced 43 5 of the MSW in the state Colvero et al 2017b IBGE 2016 The popula tion density of these municipalities is 330 inhabitants km 2 IBGE 2016 2 1 Management model and host municipality of the proposed shared MSWMF The proposed MSWMF will be based on BNDES 2014 due to the area s population and MSW production SM Tables 1 and 2 This model aims to meet the PNRS which stipulates that MSWMF must establish streams that obey the waste management hierarchy Brasil 2010 Alas virtually no actions are aimed at reducing waste produc tion in Brazil at the moment such as initiatives to encourage changes in people s consumption patterns or information about life cycle impacts and resource costs Brasil 2010 EC 2008 Godecke Naime Figueiredo 2012 So to change the current MSW management scenario it is mandatory to abandon obsolete waste disposal facilities and look for alternatives focused on circular economy i e to keep the resources in the economy for as long as possible Malinauskaite et al 2017 Merli et al 2018 Three alternatives for biowaste treatment in the municipalities were defi ned regarding the minimum MSW handling capacity by technology Tsilemou and Panagiotakopoulos 2006 HC home composting for 13 of the 19 municipalities which will handle less than 2 000 t year 1of biowaste between 2021 and 2040 SM Table 3 The generated biowaste is sustain ably treated in households avoiding collection and transport costs and generating a compost that can be used in orchards and gardens V zquez and Soto 2017 CC community composting or AD anaerobic digestion for the six municipalities that will treat more than 2000 t year 1 of biowaste SM Table 3 between 2021 and 2040 The choice between CC or AD was supported by an economic analysis Source separated biowaste is sent to a local windrow compost Nomenclature Acronym Meaning ADanaerobic digestion CCcommunity composting CF cash fl ow HChome composting IRRinternal rate of return LHVlower heating value MARRminimum acceptable rate of return MRFmaterials recovery facility MSWmunicipal solid waste MSWMF municipal solid waste management facility NPVnet present value O Russo 2003 mass point geometry was applied as explained in SM Item 3 Regarding the landfi ll the most suitable construction area was found through the methodology of Colvero et al 2018 and Gorsevski et al 2012 2 2 Landfi ll diversion targets and the proposed scenarios The municipalities of Goi s must propose an MSWMF to meet the landfi ll diversion targets of recyclables and biowaste from landfi lls as established in the National Plan for Solid Waste PLA NARES MMA 2012a Table 1 Based on those diversion targets three future scenarios have been defi ned according to the Brazilian Ministry of the Environ ment These scenarios should be designed for a 20 year horizon MMA 2012b between 2020 year of the initial MSWMF construc tion investments and 2040 end of life of the proposed MSWMF The diversion targets should be achieved between 2021 begin ning of MSWMF operation and 2031 year of the last PLANARES target From 2031 to 2040 it is expected that the entire facility will stabilise and maintain the diversion percentages of 2031 The amount of MSW to divert from the landfi ll between 2021 and 2040 was obtained from the estimated MSW production of the 19 municipalities evaluated by Colvero et al 2017b The three future scenarios are as follows Pessimistic scenario the PLANARES diversion targets MMA 2015 planned for 2015 and 2027 are reached in 2023 and 2031 respectively In this scenario the objective is to partially achieve the PLANARES targets as the diffi culties inherent to the deployment and operation of a new MSWMF mean the lin ear diversion rate is lower Moderate scenario the planned PLANARES targets MMA 2015 for 2019 are reached in 2023 In 2031 the facility attains the mean between the planned targets of 2017 and 2031 In this scenario the planned diversion targets for 2023 and 2031 will not be attained but there will be a higher linear diversion rate than in the pessimistic scenario constituting a plausible hypothesis Optimistic scenario the desired landfi ll diversions are attained in 2023 and 2031 In this scenario the proposed MSWMF for the 19 municipalities will operate as expected 2 3 Characterisation and heating value of MSW in Goi s Before calculating the lower heating value LHV characterising the MSW in the municipalities of Goi s fi rst is necessary in order to obtain the amount of energy that the incineration facility will sell annually According to Colvero et al 2016 this MSW is typi cally composed of 55 9 biowaste 31 9 recyclables and 12 2 other waste And the estimated average detailed characterisation of MSW in Goi s was obtained from Lima et al 2018 As MSW diversion targets are different Table 1 for each year and scenario the equations presented in SM Item 4 Matos and Pereira 2005 were used to calculate the LHV of the MSW submit ted to incineration each year for the three scenarios 2 4 MSWMF costs and economic viability analysis The investment and operating costs were calculated in Brazilian reais R using exchange rates from the Central Bank of Brazil BCB 2017 when necessary In 10 31 2018 R 1 0 2373 EUR US 0 2690 BCB 2017 This study s values were presented in Brazilian currency because they were extrapolated to 2021 and obtained from the mean infl ation between 2007 and 2016 as in item 2 4 However the presented conversion aids readers to obtain the values in a more global currency While the MSWMF investment costs will be insured by the Government of Goi s NURSOL UFG 2015 the operation and maintenance O Costs and revenues shared between all the 19 municipalities the costs of incineration landfi lling and transport of incineration refuse to the landfi ll and revenues from the sales of Table 1 Goi s diversion targets for MSW disposal in landfi lls Source Adapted from MMA 2012a Goal Landfi ll diversion targets 2015 2019 2023 2027 2031 Reduction in the percentage of landfi lled dry recyclable waste1315182125 Reduction in the percentage of landfi lled biowaste1525354550 Source Adapted from MMA 2012a D A Colvero et al Waste Management 102 2020 823 837825 electricity produced via incineration will be divided propor tionally between each municipality according to the MSW per centage that each municipality sends for incineration Other individual shared costs the TS costs and MSW transport to incineration will be individual or shared In the fi rst case when municipalities carry only their own MSW to incineration directly or through a TS these costs will be individual How ever in the second case for the other municipalities that will share the TS MSW transport to incineration will also be shared This division of TS and MSW transport costs will be proportional to the amount of MSW produced by each municipality The economic viability analysis of the project made use of cash fl ows CF and consequently Net Present Value NPV Internal Rate of Return IRR minimum acceptable rate of return MARR and payback period Barros 2017 The annual rate of income tax used for the NPV and IRR analysis was 15 Martins et al 2016 CF is the net amount of funds obtained by the algebraic sum of inputs revenue and outputs costs during the time of the project And the NPV calculates the current value of a series of future rev enues from which the initial investment is subtracted Sanches et al 2013 When greater than zero it indicates that the invested capital will be recovered IRR is a reference measure that sets an NPV of zero When IRR is greater than the stipulated MARR the project will be economically viable otherwise it should be rejected Martins et al 2016 The annual rate of income tax used for the NPV and IRR analysis was 15 Martins et al 2016 And fi nally the payback period is the time in years required to recover the invested capital Sanches et al 2013 In this study all revenues and operating costs for the MSWMF were updated monetarily Soares et al 2012 by applying the mean infl ation in Brazil from 2007 to 2016 which was 6 217 per year IBGE 2017a and then extrapolating this to 2020 begin ning of the project using Equation 1 Lima 2015 Soares et al 2012 VF VP 1 i n 1 where VF Future value R VP Present value R i Annual inter est rate n Elapsed time years 2 4 1 MSW collection and transport costs Because kerbside collection is already consolidated in Goi s an MSWMF with this kind of operation was considered To calculate theO and R 0 49 t 1 km 1 for the two municipalities which will carry their MSW directly to incineration in their own vehicles both values extrapolated for 2020 Bezerra 2012 Lastly Goi nia will send 82 9 of its MSW directly to incineration costing R 0 49 t 1 km 1 at a mean distance of 21 9 km from the urban centre and 17 1 through the TS 27 1 km away at a cost of 0 32 t 1 km 1 According to Vergara et al 2016 the 53 difference in com parison to long haul vehicles is because a 10 t vehicle consumes twice the fuel in L t 1 km 1 that a 25 t vehicle does hence the unit value for the two municipalities that will carry their MSW directly to incineration Additionally fuel costs represent almost 50 of the total expenses of a collection vehicle Marques 2015 2 4 2 Costs and revenues of recovery facilities for recyclables MRF require machines and operators to segregate the recyclable materials from the remaining waste to be sold to the recycling industries BNDES 2012 Grimberg and Blauth 1998 To calculate the investment and O Cerda et al 2018 Biogas is composed of methane CH4 between 45 and 70 and carbon dioxide CO2 between 35 and 60 and can be used for electricity production Gueri et al 2018 Woon and Lo 2016 To calculate the costs of the two composting types and AD dif ferent methodologies were used HC the mean investment and operating costs were obtained from EC 2000 and are shown in Table 2 The calculations are based on a 300 litre composter with a 10 year lifetime Carvalho et al 2011 EC 2000 To calculate the necessary number of homes with composters to comply with the biowaste diversion targets the mean number of inhabitants per domicile for each municipality was used SM Table 5 For Melo et al 2016 HC has an effi ciency of 61 which is the percentage diverted from fi nal disposal To guarantee the PLANARES diversion targets for biowaste 20 more composters were added beyond those strictly necessary CC and AD investment and operating costs of windrow CC and AD are presented in Table 2 While CC contemplates phases of intensive composting and maturation AD uses dry thermophilic digestion to treat source separated biowaste Tsilemou and Panagiotakopoulos 2006 It was considered that only 80 of waste destined for the CC and AD through separate collection will be diverted from MSW disposal facilities i e there will be a 20 rejection rate due to contaminants In addition to costs AD also generates revenue from the sale of electricity According to Fern ndez Gonz lez et al 2017 the elec tricity generated each year is calculated through the biogas recov ered in the process Equation 2 According to ANEEL 2018 electricity from biogas will be marketed at 319 48 R MW h 1 extrapolated to 2020 EI 0 28 B CH4 p LHVCH4 gb 1 000 2 where Ei produced electricity in MW h 0 28 conversion from MJ to kW h 1 MJ 0 28 kW h B yearly treated biowaste in AD t year 1 CH4 P methane generation ratio from the MSW organic frac tion Nm3 t 1 As in Fern ndez Gonz lez et al 2017 a fi gure of 115 Nm3 t 1was applied LHVCH4 methane lower heating value 37 2 MJ Nm 3 as in G mez et al 2010 and Lombardi and Carnevale 2016 b biogas to electricity conversion effi ciency A value of 0 29 was used for internal combustion engines to account for the electricity consumption of the facility Fern ndez Gonz lez et al 2017 2 4 5 Incineration costs and revenues Incineration is a waste recovery process that produces heat and or electricity from the heating pow