Format And Type Fonts CHEMICAL ENGINEERING TRANSACTIONS VOL. 29, 2012 A publication of The Italian Association of Chemical Engineering Online at: www.aidic.it/cet Guest Editors: Petar Sabev Varbanov, Hon Loong Lam, Jiří Jaromír Klemeš Copyright © 2012, AIDIC Servizi S.r.l., ISBN 978-88-95608-20-4; ISSN 1974-9791 DOI: 10.3303/CET1229225 Please cite this article as: Margallo M., Aldaco R., Bala A., Fullana P. and Irabien A., (2012), Best available techniques in municipal solid waste incineration: state of the art in Spain and Portugal, Chemical Engineering Transactions, 29, 1345-1350 1345 Best Available Techniques in Municipal Solid Waste Incineration: State of the Art in Spain and Portugal María Margallo*a, Rubén Aldacoa, Alba Balab, Pere Fullanab, Ángel Irabien a a Departamento de Ingeniería Química y Química Inorgánica, Universidad de Cantabria, Avda. de Los Castros, s.n., 39005, Santander, Spain; b Escola Superior de Comerç Internacional (ESCI-UPF), Pg. Pujades 1., 08003 Barcelona, Spain margallom@unican.es In the year 2010 more than 24 Mt and 5 Mt of Municipal Solid Waste (MSW) were generated in Spain and Portugal. Landfilling, incineration and recycling are the most common treatments. In 2010, in the Iberian Peninsula between 58-6 2 % of the MSW generated was sent to the landfill, 9-19 % was incinerated and the rest was recycled and composting (EUROSTAT, 2010). Despite landfilling is still the most common practice, waste treatment by means of an incineration process has increased. The main advantages of this type of waste treatment are the reduction of mass and volume of residues and the energy recovery. Nevertheless, incineration had gained a bad reputation owing to the environmental impact, in particular, due to the emissions of acid gases, dioxins and furans (PCDD/F) and greenhouse gases. To assess the environmental advantages and disadvantages as well as the potential environmental impacts of waste incineration a life cycle perspective is required. Within this framework is the development of FENIX-Giving Packaging a New Life, a 3-year European LIFE+ funded project. This work is just the first step within this project where a database and a model based on Life Cycle Assessment (LCA) to assess the environmental impacts of waste incineration in Spain and Portugal will be developed. Particularly, the aim of this paper is to review the different technologies applied to MSW solid waste incineration and to carry out both the diagnosis of the current situation at the incineration plants in Spain and Portugal and to collect data to develop the Life Cycle Inventory (LCI). 1. Introduction Municipal Solid Waste (MSW) generation in Europe has increased regularly in recent years, amounting in 2010 to more than 2 billion tons of waste, that is to say a waste generation rate of 502 kg MSW/person. The same growth trend can be seen in Spain and Portugal, where in 2010 a waste generation of 535 and 514 kg of MSW/per capita was reached respectively. In 2010 in Spain more than 24 Mt of MSW were generated, 58 % being sent to the landfill, 9 % incinerated and the rest being recycling and used produce compost. For the same year, in Portugal more than 5 Mt of municipal solid waste were generated. 62 % of this waste was sent to the landfill, 19% was incinerated and the rest was recycled and composting (EUROSTAT, 2008). According to the available data, from 1998 to 2010 an increase in the incineration share of 68 % in Spain and 100 % in Portugal has come about. This rapid development of the sector has taken place over the last 10 to 15 years driven by the legislation specific to industry that has reached reducing emissions to air (European Commission, 2006). The main advantages of this type of waste treatment are the reduction of mass and volume of residues and the recovery of energy content in that waste with a significant heating value. However, incineration had 1346 gained a bad reputation owing to the environmental impact specifically due to the emissions of acid gases, dioxins and furans (PCCD/F) and greenhouse gases (Chevalier et al., 2003, Morselli et al., 2007). To assess the advantages and disadvantages and the environmental impacts of the incineration process a life cycle perspective is required. Life Cycle Assessment (LCA) is a powerful tool for assessing the environmental performance of a product, process or activity from “cradle to grave” (ISO 2006a and 2006b). Within this framework is the development of FENIX-Giving Packaging a New Life, a 3-year European LIFE+ funded project that started in January 2010. The aim of this project is to develop a flexible and user-friendly software tool to be used by Spanish and Portuguese municipalities and other territorial organizations, to obtain LCA results for packaging waste management, integrating environmental, economic and social aspects. This work is just the first step in the development of a database and a model based on LCA to assess the environmental impacts of waste incineration in Spain and Portugal. Specifically, the aim of this paper is to review the different technologies applied to MSW solid waste incineration and to carry out both the diagnosis of the current situation at the incineration plants in Spain and Portugal and to collect data to develop the Life Cycle Inventory (LCI). 2. The incineration process The main objective of Municipal Solid Waste (MSW) incineration is to treat waste so as to reduce its volume and hazard, while capturing or destroying potentially harmful substances. Incineration processes can also provide a means to enable recovery of the energy, mineral and/or chemical content from waste. Incineration is used as a treatment for a very wide range of waste types such as MSW, Hazardous Waste (HW) or sewage sludge (European Commission, 2006). 2.1 Thermal treatment Different types of thermal treatments are applied to the different types of waste, however not all treatments are suited to all waste. The most common technologies applied are grate incinerators, rotary kilns, fluidised beds (FB) and pyrolysis and gasification systems. For MSW and Refuse Derived Fuel (RDF) incineration grates are widely applied, FB and rotary kilns are also applied but to a lesser extent. On the other hand, pyrolisis and gasification are rarely applied because they are still considered as emerging technologiesthis. In poarticular it is a less proven technology and the unclear economic benefits hamper a larger market penetration (Van Caneghem et al., 2012). In particular, in Spain and Portugal only grate incinerators and fluidised beds are applied at MSW incineration plants. In Spain 80 % of thermal treatment systems are grates while in Portugal this goes up to 100 %. Grate incinerators (GI): in Europe approximately 90% of the installations treating MSW use grates. Grate incinerators usually comprise the waste feeder, incineration grate, bottom ash discharge, the incineration air duct system to ensure complete combustion, incineration chamber and auxiliary burners to heat up the furnace to a specified temperature. The optimum incineration conditions in which to achieve a good burn out of the gases are a minimum gas phase combustion temperature of 850 ºC (1,100 ºC in some hazardous wastes) and a minimum residence time of the flue-gases, above this temperature, of 2 seconds after the last incineration air supply (European Commission, 2000).The main types of grates are rocking, reciprocating, travelling and cooled grates (European Commission, 2006). Fluidised beds (FB): they are widely applied to the incineration of finely divided waste such as RDF and sewage sludge. The FB incinerator is a lined combustion chamber in the form of a vertical cylinder. In the lower section a bed of sand, combustion ash, or other sand-like material is suspended in an upward flowing airstream. Normally this type of incineration requires a preparatory process step which makes raise the process costs. The main types of FB are stationary or bubbling fluidised bed, spreader-stoker furnace and rotating FB (European Commission, 2006; Van Caneghem et al., 2012). 2.2 Energy recovery The majority of the energy produced during combustion is transferred to the flue-gases. Cooling of these gases allows energy recovery and the cleaning of flue-gases before they are released into the atmosphere. Conventional recovery involves passing the flue gases through a boiler, thereby obtaining steam, which can be turned into energy by means of an engine (White et al., 1995). The principal uses 1347 of the energy transferred to the boiler are the production and supply of heat and the production and supply of electricity. Specifically, in Spain and Portugal is carried out but the energy recovered is used for the self consumption at the plant and sold to the public grid. 2.3 Flue-gas treatment (FGT) systems Before the emission to air, flue gases must be cleaned by a combination of individual process units that together provide an overall treatment. The number of different treatment processes used varies widely from plant to plant, reflecting the emission standard required (Chevalier et al., 2003). Different techniques are applied to clean different pollutants such as acid gases, organic compounds or NOx. Particulates: the main types of techniques are electrostatic precipitator (EP), ionisation wet scrubbers (IWS), fabric filters or bag filters and cyclones and multi-cyclones. Acid gases (HCl,HF and SOx): these gases are cleaned using alkaline reagents (CaO and Ca(OH)2) by means of dry, semidry or wet processes. The main different between them is that in the wet process the reaction product is aqueous requiring a treatment prior to discharge (White et al., 1995). Nitrogen oxides (NOx): NOX are reduced to N2 and water vapour by the reduction agent (NH3 or urea) applying Selective Non-Catalytic Reduction (SNCR) process or Selective Catalytic Reduction (SCR) process where the flue-gas pass over a catalyst (European Commission, 2006). Dioxins and furans (PCCD/F): most usual treatment is adsorption on activated carbon but also bag filters and SCR could be applied. 2.4 Solid residue treatment The main waste types arising from the combustion stage are bottom ash and boiler and fly ashes that are usually treated together. They are generally disposed of, often after a solidification process with water and cement, but could be used as a filling material in civil construction. Slag is usually subjected to magnetic separation, from which a metallic fraction is obtained made up of metallic waste contained in MSW and non-metallic fraction comprising ceramic and vitreous materials and particles not burned in the combustion process. The metallic fraction, ferrous scrap, is used to produce steel in an electric arc furnace (Lopez-Delgado et al., 2003). The inert material is sent to landfill. 3. The incineration of MSW in Spain and Portugal According to the European Pollutant Release and Transfer Register E-PRTR and Directive 2008/1/EC, the so-called IPPC Directive (that replaced Directive 96/61/EC), dated September 2010, 10 Spanish facilities and 3 Portuguese plants are included in group 5.b; installations for the incineration of non- hazardous waste with a capacity of 3 tonnes per hour (European Parliament and Council, 2006). Figure 1 shows a map of the plants location. Figure 1. Location of the Spanish and Portuguese incinerators (Source: own elaboration based on E- PRTR information). Zabalgarbi (Vizcaya, Basque Country) URBASER (Cantabria) UTETEM (Barcelona , Catalonia) TERSA (Barcelona, Catalonia) TRARGISA (Girona, Catalonia) SIRUSA (Tarragona, Catalonia) TIR Madrid, (Madrid) SOGAMA (A Coruña, Galicia) REMESA (Melilla) TIRME (Palma de Mallorca, Balearic Islands) VALORSUL (Lisbon) LIPOR (Porto) VALORAMBIENTE (Madeira) 1348 In relation to the Spanish incineration plants, there are four plants in Catalonia (Spain). Two of them are located in Barcelona -Planta de Valortització Energética Sant Adrià de Besòs (TERSA) and Tractament i Revaloritzaió de Residus del Maresme, S.A. (UTETEM)- one in Girona -TRARGISA area de residus- and the last one in Tarragona -Incineradora de Tarragona (SIRUSA)-. Table 1 shows technical and operational data for the four incineration plants sited in Catalonia (AEVERSU, 2010). Table 1: Technical and operational data of TERSA, UTETEM, TRARGISA, SIRUSA. Tersa Utetem Trargisa Sirusa Type furnace Von Roll grate Martin travelling grate Martin reverse- acting grate Reciprocating grate Tons MSW incinerated 321,728 170,274 35,053.46 151,849 LHV (kcal/kg) 1,900-2,200 2,100 1,800 2,000 Energy production (MWh) 167,504 86,105 44,552 Energy sales (MWh) 144,761 72,809 N.A Slag (t) 55,642 41,973 6,338 30,921 Ashes (t) 12,039 7,237 650 3,508 Flue gases treatment SNCR, bag filters, scrubbers, electro filters, activated carbon SNCR, semidry and dry scrubber, bag filter Bag filter, activated carbon Semidry system, bag filter, activated carbon Three incinerators are sites in the North of Spain. In particular in Cantabria -Planta de Tratamiento Integral de RSU de Cantabria (URBASER)-, Vicaya (Basque Country) -Zabalgarbi, S.A.- and in A Coruña (Galicia) -Complejo medioambiental de Cerceda (SOGAMA)-. The rest of incineators are located in Madrid -TIR Madrid-, Melilla –PIR Melilla, REMESA- and in Mallorca (Balearic Islands)- TIRME S.A.-. In Table 2 and 3 are given the data of these plants and in Table 4 the emissions to air of all the Spanish incinerators are shown (AEVERSU, 2010) . Table 2: Technical and operational data of Zabalgarbi, SOGAMA and URBASER. Zabalgarbi SOGAMA URBASER Type furnace Reciprocating grate Circulating FB Roller grate Tons MSW incinerated 223,933 550,000 113,338 Energy production (MWh) 661,160 335,078 82,800 Energy sales (MWh) 632.000 332,761 N.A Slag (t) 42,547 69,038 14,972 Ashes (t) 8,375 33,240 4,536 Flue gases treatment SNCR, semidry system, bag filter, activated carbon Semidry system, bag filters, activated carbon Scrubber, bag filter, activated carbon Table 3: Technical and operational data of Zabalgarbi, SOGAMA and URBASER. TIR Madrid PIR Melilla TIRME Type furnace bubbling FB serrated grate roller and cooled grates Tons MSW incinerated 418,905 40,986.7 294,185 LHV (kcal/kg) 3,500 1,400-3,000 1,800 Energy production (MWh) 234,841 N.A 152,389 Energy sales (MWh) 170,014 11,298 119,759 Slag (t) N.A 9,397 69,133 Ashes (t) N.A 1,043 28,242 Flue gases treatment Cyclones, bag filters, SCR, scrubber, activated carbon Semidry system, bag filter, activated carbon Semidry scrubber, SCR, bag filter, activated carbon 1349 Table 4: Emissions to air of the Spanish incinerators in 2009. Pollutants mg/Nm 3 Incineration plants Tersa Utetem Trargisa TIR Madrid Zabal- Garbi Sirusa Tirme Sogama PIR Melilla Urbaser HCl 5.9 2.11 3.8 4.2 3.2 7.0 0.0 <2.5 8.7 5.3 Particles 3.24 2.73 3.0 9E-1 8.7 7.0 <1.1 <6 22.6 3.68 CO 35.9 24.9 4.1 14.1 4.47 8.35 <4.0 <27 <4.6 11.6 HF 6E-2 1.9E-1 0.0 6E-2 2.8E-2 1.0 <4E-2 <1.5 <3.2E-2 3.3E-1 SO2 14.4 20.15 0.0 3.2E-1 11.37 33 <7.5 <14 <13.6 1.36 Metals (1) 3.9E-2 3.8E-2 5E-3 5.3E-2 6.1E-2 6E-3 <2.9E-2 7E-2 <9.8E-2 1.4E-1 Cd+Tl 7.2E-3 5.4E-3 2.5E-3 <5E-4 2E-3 4.4E-3 <2E-3 <3E-2 <7.2E-3 1.4E-2 NH3 6.1E-3 2.3E-3 N.A N.A N.A N.A N.A N.A N.A N.A TOC 1.59 3.63 N.A N.A N.A N.A N.A N.A N.A N.A Hg N.A (3) N.A 3E-3 6E-4 2E-3 5E-2 <2.5E-3 <1E-2 <1.6E-4 2.5E-3 VOC N.A N.A 3.4 1.4 1.4 8E-1 <5 <7 <1.4 2.8 PCDD/F (2) 1.4E-2 4.6E-3 6E-3 9E-3 7E-3 3E-3 5.6E-3 1.4E-2 2.5E-2 1.7E-2 NOx 135 ppm 155 225 123 157 161 51.3 116 195 158 1) Sb+As+Pb+Cr+Co+Cu+Mn+Ni+V; 2) ng ITEQ/Nm 3 ; 3) N.A: Data Not Available. In Portugal the 3 incinerators are located in Lisboa -VALORSUL, Valorização e Tratamento de Resíduos da Área Metropolitana de Lisboa (Norte), S.A S.-, Madeira -Valor Ambiente Gestão e Administração de Resíduos da Madeira- and Porto –LIPOR, Serviço Intermunicipalizado de Gestão de Resíduos do Grande Porto-. In Table 5 the main data and emissions of the Portuguese incinerators are given (VALORSUL, 2010, Valor Ambiente, 2010, LIPOR, 2010). Table 5: Technical and operational data and emissions to air of the Portuguese incinerators in 2009. VALORSUL Valor Ambiente LIPOR Incineration capacity (ton/year) 662,000 126,000 400,000 Type furnace Reverse-Acting grate Roller grates Grate Energy production (MWh) N.A N.A 200,000 Slag (kg/ton MSW) 200 160 N.A Ashes kg/ton MSW) 30 N.A N.A Emissions to air (mg/Nm 3 ) CH4 N.A 515,000 N.A PCDD/F N.A 1E-4 N.A CO2 502,000,000 N.A 357,000,000 Hg N.A N.A N.A HCl 17,600 N.A N.A NOx 502,000 N.A 265,000 N2O 59,500 N.A N.A NH3 N.A N.A 11,700 4. Conclusions In this work the most relevant technologies applied in MSW incineration in Spain and Portugal have been determined and will be included in the future database and model based on LCA. The main data are collected from the European Pollutant and Transfer Register (E-PRTR), the Business Association of MSW valorisation (AEVERSU) and websites of different incineration plants.Regarding the thermal stage, grate incinerators, rotary kilns and FB could be applied to a range of waste types. In the case of MSW treatment, only grate incinerators and FB are used. Fluidised bed are applied to a smaller extent than grate incinerators because a preparatory stage is required when heterogeneous waste is treated. Specifically, in Spain the application of grate incinerators makes up 80% of incinerators, rising to 100% in Portugal. The majority of the energy produced during combustion is used for the self consumption at the plant and sold to the public grid.The amount of energy produced differs from one plant to another 1350 and depends on the amount of waste incinerated and the heating value. Before being emitted the flue gases need treatment. Different systems are applied depending on the pollutants contained in the gases. For reducing particulate emissions in Spain and Portugal, electrofilters and bag filter are the technologies that are most often applied, and to a less extent cyclones and multicyclones. Acid gases such are treated through dry and semi-dry processes using an alkaline reagent such as CaO and Ca(OH)2. To remove NOx Selective Non Catalytic Reduction (SNCR) and the Selective Catalytic Reduction (SCR) are applied. In both cases NH3 or urea is the reagent used to reduce the NOx to N2. Other important pollutants generated during the combustion are organic compounds like PCDDD/F. These substances are usually treated by absorption on activated However, SCR systems, catalytic bag filters, and static bed filters are also available. With regard to waste, slag and ashes (bottom, fly and boiler ash) are generated during the combustion process. Ashes are usually disposed of at a landfill, sometimes following a stabilization process with cement and water. Slag is usually subjected to magnetic separation, with the metallic fraction, ferrous scrap used to produce steel in an electric arc furnace and the inert material sent to landfill. Acknowledgement The authors gratefully acknowledge the financial support of FENIX-Giving packaging a New Life project. References AEVERSU, 2011. Spanish Association of Municipal Solid Waste valorization accessed 15.12.2011. Chevalier, J., Rosseaux P., Benoit V., Benadda B., 2003, Environmental assessment of flue gas cleaning processes of municipal solid waste incinerators by means of the life cycle assessment approach. Chemical Engineering Science, 58 (10), 2053-2064. E-PRTR, European Pollutant and Release Transference Register accessed 22.10.2011. European Commission, 2000, Directive 2000/76/CE of the European Parliament and of the Council of 4 December 2000 on the incineration of waste, Brussels, Belgium European Commission, 2006, Reference Document on the Best Available Techniques for Waste Incineration Brussels, Belgium European Parliament and Council, 2006, Regulation (EC) No 166/2006 of the European Parliament and of the Council of 18 January 2006 concerning the establishment of a European Pollutant Release and Transfer Register and amending Council Directives 91/689/EEC and 96/61/EC. EUROSTAT, European Commission, 2010 accessed 11.03.2011. FENIX project accessed 16.6.2011. ISO, 2006a, ISO 14040: Environmental management - Life cycle assessment - Principles and framework. ISO, 2006b, ISO 14044: Environmental management - Life cycle assessment - Requirements and guidelines. LIPOR- Serviçio Intermunicipalizado de Gestão do Grande Porto accessed 22.10.2011. López-Delgado A., Peña C., López V., 2003, Quality of ferrous scrap from MSW incinerators: a case study of Spain. Resources, Conservation and Recycling, 40(1), 39-51. Morselli L., Luzi J., De Robertis C.D., Vassura I, Carrillo V., Passarini F., 2007, Assessment and comparison of the environmental performances of a regional incinerator network, Waste management, 27 (8), S85-S91. Valor Ambiente– Waste management of Madeira, S.A. accessed 25.10.2011. Valorsul, S.A. accessed 22.10.2011. Van Caneghem J., Brems A.Lievens P., Block C. Billen P, Vermeulen I., Dewil R, Van Caneghem J., Brems A.Lievens P., Block C. Billen P, Vermeulen I., Dewil R, Baeyens J, Vandecasteele C., 2012, Fluidized bed waste incinerators: Design, operational and environmental issues. Progress in Energy and Combustion Science, 38 (4), 551-582. White P.R., Franke M., Hindle P, Integrated Solid Waste Management. 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Glasgow, United Kingdom. http://www.aeversu.com/ http://prtr.ec.europa.eu/ http://epp.eurostat.ec.europa.eu/ https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26431681900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26634861900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26634861900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=15924743300&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=55124528600&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=35759939900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=6507444355&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26431681900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26431681900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26634861900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=26634861900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=15924743300&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=55124528600&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=35759939900&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=6507444355&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=7006171152&eid=2-s2.0-84861546942 https://vpnuc.unican.es/authid/,DanaInfo=www.scopus.com+detail.url?authorId=7005856566&eid=2-s2.0-84861546942