Int J Life Cycle Assess (2017) 22:1957–1968 DOI 10.1007/s11367-017-1282-2

LCA OF MANAGEMENT SYSTEMS

A study on the environmental aspects of WEEE in a Brazilian company

Juliana Mendes Campolina1 & Carolina São Leandro Sigrist1 & Jane Maria Faulstich de Paiva1 & Andréa Oliveira Nunes1 & Virgínia Aparecida da Silva Moris1

Received: 6 July 2016 /Accepted: 9 February 2017 /Published online: 13March 2 017 # Springer-Verlag Berlin Heidelberg 2017

Abstract the consumption of energy and in CO2 emissions. When com- Purpose The high consumption of electrical and electronic pared to the production of virgin ABS and HIPS, the recycling equipment motivated by the rapid technological advances processes for such showed a reduction in energy con- seen over the years has lead to an increase in the generation sumption by approximately 90% for both plastics and a reduc- of waste electrical and electronic equipment (WEEE). Such tion in CO2 emissions by approximately 84% for HIPS and residues contain various dangerous substances and therefore 87% for ABS. The plastics recycled by the company retain deserve special attention. To that end, the Brazilian Policy on over 90% of their virgin mechanical properties. Solid Waste has provided guidelines on integrated and solid Conclusions The study shows that recycling is highly relevant , such as consumer electronics, aiming at and that components present in WEEE received appropriate their appropriate disposal and treatment through reverse logis- destination and treatment. Recycling avoids environmental tics. In this context, the present work focuses on studying the impacts as it prevents WEEE from being disposed of in land- recycling of some WEEE plastics. fills and as the pellets of recycled plastics can re-enter the Methods This study was conducted using the methodological supply chain as raw materials. Considering the legislation in framework presented in the International Standard ISO Brazil, the stage of collection/transport/treatment of WEEE 14040:2006 and aimed to determine the life cycle inventory conducted by the company under study presents strong indi- (LCI) of a WEEE process in a company in cations of contributions to the environment, society, and econ- Brazil. Having collected the data, it was possible to identify omy of the country. and quantify the environmental aspects caused by the recycling process of major plastics (acrylonitrile-butadiene- Keywords Environmental aspects . Life cycle inventory . styrene (ABS) and high impact polystyrene (HIPS). The study Recycled plastics . Waste electrical and electronic equipment was conducted in the only company in Brazil that operates WEEE plastic recycling in large scale. Results and discussion Some of the environmental aspects caused during the recycling process of the plastics under study 1 Introduction were identified and quantified. As a result, besides presenting the inventory, it was also possible to determine a reduction in Currently, it is possible to notice an increase in the consump- tion of electrical and electronic equipment (EEE), which is often the result of technological advancements and a model Responsible editor: Martin Baitz of consumption aimed at the acquisition of new products and their quick replacement. This, in turn, leads to the accelerated * Virgínia Aparecida da Silva Moris [email protected] generation of Waste electrical and electronic equipment (WEEE) (Tanskanen 2013). 1 Federal University of São Carlos, Rod. João Leme dos Santos, km In 2015, in Europe, it was estimated that approximately 110 (SP-264) Bairro do Itinga, Sorocaba CEP, São Paulo 18052-780, 12 million t of electronic waste was generated—the equivalent Brazil to 14 kg per capita a year (Goosey 2004).

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WEEE is composed of glass, plastics, metals, and hazard- secondary raw materials. Menikpura et al. (2014)havemadea ous substances such as heavy metals and flame retardants, detailed investigation of the effectiveness of WEEE recycling which pose a threat to human health and to the environment on greenhouse gas (GHG) reduction by analyzing the overall if disposed of incorrectly. These substances are present in recycling process of major home appliances in Japan, con- different components of the equipment. Examples are antimo- cluding that a significant amount of GHG emissions could ny, found in semiconductors, alloys, and welds, and arsenic, be avoided when compared with the virgin production of ma- found in printed circuit boards, among others. Plastics, for terials by implementing an appropriate WEEE recycling and example, pose a risk to the environment when disposed of in program. Wager et al. (2011) conducted a landfills due to their long-term degradation process and to the study in order to quantify the environmental impacts of the presence of flame retardants (Jonkers et al. 2016; Tsydenova collection, dismantling, recycling, incineration, and disposal and Bengtsson 2011; Horner and Gertsakis 2006;Yu2005). stages of WEEE in landfills in Switzerland. Additionally, plastics occupy a lot of space in landfills and This study aims to develop the life cycle inventory (LCI) of thus could be made better use of or recycled before being recycling WEEE plastics from information and communica- discarded. In 2015, the world production of thermoplastic tion technology products (ICT) at a company in the region of resins was 260 million t. Latin America represents 5% of this Sorocaba/SP (Brazil). The major polymers recycled during the production, with Brazil accounting for almost half of this val- study period were acrylonitrile-butadiene-styrene (ABS) and ue (ABIPLAST 2015). high impact polystyrene (HIPS). Having the data necessary According to the Social Environmental Institute for Plastics for the preparation of the LCI, it was possible to identify and in Brazil, the mechanical recycling rate of post-consumer plas- quantify some environmental aspects related to the recycling tic in Brazil is in the range of 21.7%, 3 % below the European process in question, such as (i) gaseous emissions, (ii) gener- average index of 24.7%. The semi- and non-durable consumer ation of solid waste, and (iii) energy consumption. goods sector is the largest consumer of recycled plastic in the The present study is the first to evaluate the environmental country, with an index of 41%, followed by the construction aspects of WEEE recycling in large scale in Brazil. It was and infrastructure sector with 16% and the agriculture, with carried out in the only large-scale company in the country that 11.8% (Plastivida 2011). collects and industrially recycles WEEE plastics. The compa- In this context, it is necessary to search for appropriate ny is also responsible for WEEE reverse logistics and the technologies and WEEE management sources, such as proper disposal of all unprocessed other materials and elec- recycling processes. The environmental management tool tronic components during the recycling process. In 2015, for used to evaluate the environmental performance of a product, example, the company processed 1340 t of electronic waste process, or service throughout its life cycle is known as life and put 270 t of plastic for in the manufacture of new cycle assessment (LCA) (Curran 2012). products. The life cycle assessment (LCA) related to WEEE requires large amount of data because of the electronic product com- plexity and its inherent technology. Nevertheless, this type of 2 Literature review tool has been used in a successful way to develop ecodesign strategies in the electronics business (Andraw and Andersen 2.1 Electrical and electronic equipment and waste 2010). The LCA study for WEEE is usually done on a partic- ular product and from a product life point of view, including EEE are all devices that rely on electric currents or electro- focus on different waste management alternatives (Bigum magnetic fields to be operated. After the end of life of such et al. 2012). equipment, they are classified as WEEE and the global rate of The literature presents several studies on LCA related to growth of WEEE is about 3 to 5% per year (Cucchiela et al. WEEE, for instance, the study that determined the environ- 2015). Such waste is mainly composed of ferrous and non- mental impacts of WEEE plastics recycling in Europe and ferrous metals, glass, and plastics. Iron and account for which compared the incineration of such waste with the pro- almost half of the total weight, followed by plastics, which duction of virgin plastic (Wager and Hischier 2015). Hischier account for approximately 21% of the total, and the non- et al. (2005) have examined two Swiss take-back and ferrous metals, which account for 13%, where copper repre- recycling systems for computers, consumer electronics, tele- sents approximately 7% (Widmer et al. 2005). It is important communication equipments, and household appliances with a to bear in mind, however, that the weight percentage of WEEE combined approach of (MFA) and composition varies according to the type of equipment and the LCA. They concluded that the sorting and dismantling year of manufacture (Araújo et al. 2012). activities of the recycling chain are of lesser interest for The proper disposal and treatment of WEEE through companies, instead the main impact happens during the recycling provide benefits to the environment since materials treatment applied further downstream to turn the waste into in its composition are reused, thus reducing the consumption

Content courtesy of Springer Nature, terms of use apply. Rights reserved. Int J Life Cycle Assess (2017) 22:1957–1968 1959 of natural resources and energy (Tanskanen 2013; Cui and Reverse logistics provides different types of benefits and is Forssberg 2003). an important stage in the recovery system. Concerning the On the other hand, if improperly disposed of, they become environment, reverse logistics reduces the incorrect disposal dangerous to human health and to the environment as they of WEEE and the consumption of energy through recycling. contain hazardous substances. For these reasons, legislations The social benefits of this logistics relate to the generation of on WEEE have been and are being implemented in several formal employment, the increased in awareness of the popu- countries (Tsydenova and Bengtsson 2011). lation with regard to environmental issues, and the decrease in In addition, the disposal of WEEE in landfills generates health problems caused by the incorrect handling of WEEE negative environmental impacts due to the space they occupy (Abdi 2013). and to the fact the materials are not recovered. The environ- Several studies evaluate the cost involved in WEEE reverse mental impacts are considerably higher when WEEE is logistics, which lies mainly in the cost associated with the discarded in uncontrolled landfills, as there is soil and ground operation of the system due to the long distances between contamination, besides surface water contagion due to the the collection points and the destinations (Yla-Mella et al. leaching of toxic substances in such equipment by rainwater 2014;Abdi2013). (Ongondo et al. 2011; Barba-Gutiérrez et al. 2008). Kilic et al. (2015) studied a reverse logistics network de- Araújo et al. (2012) proposed a model for estimating signed for Turkey. They evaluated different scenarios, each of WEEE generation that was proposed in Brazil. Different which based on different quantities of WEEE to be collected. methods are used in this model for mature and non-mature For each scenario, the suitable locations, numbers, and types market products. The yearly WEEE generation per capita for of storage points and recycling facilities were determined so as the selected products is 3.8 kg. However, this value should be to minimize the total cost of the system. considered with care, since there are variations according to On the other hand, reverse logistics presents complexities region, location, and consumer behavior for buying, using, such as: (i) the non-uniform quality of the collected product, and discarding the equipment. (ii) the little predictability of the collection paths and routines, (iii) low volume collection, (iv) the costs of a process about which little is understood, (v) the difficulty to make plans, (vi) 2.2 Legislations the not so transparent visibility of the return, and (vii) the high financial aspects (Rogers and Tibben-Lembke 1998). Some countries have legislations on WEEE management. In WEEE return through reverse logistics contributes with up Europe, for example, there are two directives: 2002/95/CE to 18% of the growth of recycled material available in the and 2002/96/CE. The Directive 2002/95/CE (RoHS) restricts market, such as plastics. In addition, it reduces CO2 emissions. the use of cadmium, mercury, hexavalent chromium, lead, The average potential savings per tonne of aluminum, copper, polybrominated biphenyl, and polybrominated diphenyl and recycled glass are 4.5, 4.7, and 0.32 t of CO2,respectively ethers in EEE (European Union 2003a) and Directive (Abdi 2013). Oliveira (2012) presents that the polyethylene 2002/96/EC (WEEE) focuses on WEEE management through terephthalate (PET) recycling contributed to reduction of reuse, recycling, and other forms of recovery (European CO2eq emission about 1.94 t CO2 eq./t. Therefore, reverse Union 2003b). logistics is essential for the Brazilian Policy on Solid Waste Both directives were thought so that manufacturers would to be effectively implemented. assess the environmental impacts of their products throughout their life cycles and ensure their proper disposal after their end 2.3 WEEE recycling process of life through shared producer responsibility (Goosey 2004). In Brazil, the National Policy on Solid Waste has prompted The increasing generation of WEEE in recent years and the discussions on the future of solid residues. growing awareness of the public on environmental issues have This law presents guidelines on integrated and solid waste placed emphasis on WEEE treatment processes through management through their appropriate allocation and treat- recycling (Taurino et al. 2010). ment using reverse logistics for pesticide containers, batteries, The recycling process of WEEE usually starts with its col- tires, lubricating oils, electronics, and fluorescent lamps. The lection and subsequent sorting into several components, such law highlights shared responsibility for the life cycle of prod- as ferrous and non-ferrous metals and plastics, among others. ucts and states that waste management must comply with the The material is then compacted in crushers (Tanskanen 2013). following hierarchy: non-generation, reduction, reuse, Ferrous residues are normally sent to steel plants and plastics recycling, treatment, and final disposal in landfills (Brasil to recycling plants, and copper and aluminum are recycled in 2010). The Brazilian government establishes that the compa- foundries. Materials considered according to the nies need to recycle 17% of all electronic equipments sold in Brazilian National Policy on Solid Waste are sent for final Brazil (Brasil 2013). disposal in suitable landfills (Araújo et al. 2012).

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A study on material flow analysis and energy requirements plastics reduces energy consumption by approximately 80% on the recovery process of mobile phone materials identified compared to the production of virgin plastics. A major chal- that the energy needed to recover copper from such devices is lenge for mechanical recycling is that the plastic waste must half the amount needed in primary copper extraction and sim- have been effectively separated through suitable separation ilar to or greater than the amount of energy needed for refining technologies so that a high degree of purity is achieved precious metals. Nevertheless, only 2.5% of mobile phones (Dodbiba et al. 2005). This is necessary because plastics have are sent for industrial recovery (Navazo et al. 2014). WEEE different characteristics such as different melting points, den- plastic recycling is a complex process since the WEEE con- sity, and hardness, among others (Araújo et al. 2012). tains about 15 different types of polymers, including ABS, According to Oliveira (2012), the mechanical recycling is HIPS, polypropylene (PP), and polystyrene (PS). It is also seen as one of the solutions for the treatment of post-consumer common to find brominated flame retardants (BFR) like plastics in Brazil. On an industrial scale, this type of recycling polybrominated biphenyl (PBB), polybrominated diphenyl typically involves a series of treatments and preparation stages ethers (PBDE), and others (Vilaplana and Karlsson 2008; that can be outlined in the Sankey diagram of Fig. 1.Ingen- Maris et al. 2015). If disposed of or treated incorrectly, these eral, the mechanical recycling presents the separation, milling, flame retardants pose a threat to human health and to the washing, drying, extrusion, and granulation as main steps for environment (Jonkers et al. 2016). obtaining the recycled plastic. The most common plastic recycling approaches are incin- Nnorom and Osibanjo (2009) have collected waste plastic eration and mechanical recycling. Incineration provides pow- housing units of mobile phones and analyzed for lead, cadmi- er generation while mechanical recycling provides the separa- um, nickel, and silver to study the toxicity characterization of tion of plastic waste that can be reused and reinserted into the waste mobile phone plastics, concluding that there may not be production chain (Vilaplana and Karlsson 2008). Incineration any immediate danger from end-of-life mobile phone plastic emits toxic substances and so requires appropriate equipment housing if appropriately treated. At the same time, it is impor- for their treatment (Taurino et al. 2010). tant to consider the large quantities generated and the present Jang (2010) presents an overview of WEEE recycling and low-end management practices, such as burning, in most de- management in Korea. More efforts should be made to devel- veloping countries, revealing a genuine concern about the op cost-effective recycling technologies and promote the reuse potential for environmental pollution and toxicity to man and recycling of WEEE prior to its final disposal, for example, and ecology. economic incentives for collectors and the development of Recent studies have shown an increase in the use of life recycling technology. Recycling options should become a ma- cycle assessments (LCA) to evaluate environmental im- jor part of WEEE management in Korea as incineration and pacts and address the importance of WEEE recovery in landfilling are not currently accepted. some countries. The studies present benefits of WEEE Vilaplana and Karlsson (2008) point out that plastic recovery such as the reduction in energy consumption, recycling has a smaller impact on the environment when it is use of raw materials, and therefore in impacts on the en- carried out through mechanical recycling. According to vironment (Wager and Hischier 2015; Wager et al. 2011; Makenji and Savage (2012), the mechanical recycling of Biganzolietal.2015).

Fig. 1 Mechanical recycling of plastics

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2.4 LCA study on the production of virgin HIPS and ABS 14040:2006 in order to determine the LCI of recycling major plastics from WEEE collected by the company (ISO 2006). Plastics Europe (2012) used the LCA tool and the cradle-to- gate approach to assess the environmental impacts caused 3.1 Aims during the production of virgin HIPS. Data collection was carried out in 2010, over a period of 12 months. The function- The aim of the study was to determine the LCI of recycling al unit defined in the study was 1 kg of HIPS pellets. Data WEEE plastics and to compare the environmental aspects of were collected from six HIPS producers in 11 plants covering the major plastics recycled at the studied company with liter- eight European countries, which represents 95% of the pro- ature data of their virgin production. After establishing the duction capacity of this polymer in the year under study. The consolidated LCI, it was possible to identify and quantify software used to perform the LCIA was GaBi LCA 5. some environmental aspects (air emissions, energy consump- The energy demanded in the process was approximately tion, solid waste generation), so that they could subsequently 86.99 MJ/kg HIPS pellets and the global warming potential be compared to the production of virgin materials presented in was 2.43 kg CO eq./kg of HIPS pellets, where the CO emis- 2 2 the literature. sion was 2.23 kg CO /kg of HIPS pellets (Plastics Europe 2 The study compared the recycling process with the produc- 2012). tion of virgin ABS and HIPS polymers in relation to their CO Another study by Plastics Europe (2005) used the LCA 2 emissions and energy consumption. This was possible tool to assess the environmental impacts caused during the through the obtention of recycled plastics pellets. production of virgin ABS. It used the cradle-to-gate approach and the functional unit of the study was 1 kg of ABS pellets. The demand for energy was 95.34 MJ/kg of ABS pellets, 3.2 Scope the global warming potential was 3.8 kg CO2 eq./kg of ABS pellets, and the CO2 emission was 3.1 kg CO2/kg of ABS 3.2.1 The system pellets (Plastics Europe 2005). The studied system focused on WEEE plastic recycling and on the ICT equipment at a recycling company located in Brazil. The boundary system is shown in Fig. 2. 3 Methods Examples of WEEE processed at the company include cell phones, cartridges, printers, cables, and tablets. The This study was conducted using the methodological frame- process begins with the collection and transportation of work presented in the International Standard ISO WEEE to the company, which is carried out by third

Fig. 2 Studied system: plastic recycling process. Subtitle: co-products: waste, plastic packaging, cardboard, , foam, and Styrofoam. ferrous metals, glass, aluminum, aluminum with copper and stainless Scraps: factory scan materials, labels, cleaning cloths, metallic mixed steel, batteries, rubber, chargers, cartridges, CD, connectors, displays, plastics, etc. that cannot be recovered or sold. These materials are sent speakers, flats, power sources, HDD, stainless steel, DVD players, to specialized companies for incineration for power generation. Plastics: cables, motors, mouses, aluminum plates, printed circuit boards, ABS, HIPS, PC, PS, PP, and other mixed plastics, such as ABS, glass demagnetized processors, burrs, fan supports, keyboards, monitors, fiber. ABS with flame retardant, and ABS with polycarbonate and flame fans, and mixed plastics. Solid waste from packaging: pallets retardant

Content courtesy of Springer Nature, terms of use apply. Rights reserved. 1962 Int J Life Cycle Assess (2017) 22:1957–1968 parties. After that, the WEEE follows for disassembly and Greenhouse gas (GHG) emissions against electricity con- manual sorting. The plastics are identified through visual sumption and diesel aspects or by the identification stamps on some equip- GHG ¼ Σ ðÞ ðÞ ment. In unclear cases, near infrared spectroscopy (NIR) Em ee;y GWPGHGx m CEmxEFm 1 is used for light colors and infrared spectroscopy by py- EmGHG = GHG emission against electricity consump- rolysis (Py-IR) for dark colors. The devices belong to the ee,y tion in period y (t GHG); company’s analytical laboratory. The most common plas- GWP = global warming potential GHG (IPCC 2006); tics identified in the sorting stage are ABS, HIPS, poly- GHG CE = electricity consumption in month m (MWh); carbonate (PC), PS, and PP. m EF =gridCO factor in month m, against the power grid After being sorted and identified, the plastics (HIPS, m 2 serving the operating unit (t CO /MWh). ABS, and others like PP and PS) are taken to the knife 2 This study considered the grid CO emission factor in mill and then for extrusion. The plastics recycled by the 2 Brazil to be 0.1382 t CO /MWh. This value was based on company retain over 90% of their virgin mechanical prop- 2 the average of the emission values in the respective months erties confirmed by the analyses conducted at the labora- of the period studied (Brasil 2014, 2015). tory company. Therefore, the recycled plastics can be ap- plied for the same functions.

3.2.2 Functional unity 4 Results and discussion

In the present study, two LCIs were conducted, one for HIPS 4.1 Life cycle inventory and another for ABS. The functional unit used for the HIPS inventory was 1 kg of recycled HIPS pellets, and the function- Primary and secondary data were used in this study. Primary al unit used for the ABS inventory was 1 kg of recycled ABS data, i.e., direct information on the material and energy bal- pellets. ances from the period under study, as well as on the compo- sitions of the materials in the plastic recycling process, were obtained from the company. At this stage, the inputs and out- 3.2.3 Data collection period puts of the system were identified and quantified. Secondary data used were the data collected in Brazil (Brasil 2014, 2015) Input and output data relative to the productive system, such and were used in the calculations of the environmental aspects as raw materials, energy, water, air emissions, effluents, and related to energy consumption and CO emissions. solid waste generation, were collected between November 2 WEEE gets to the company through reverse logistics, 2014 and May 2015, a 7-month period. The major plastics which consists in collecting and transporting WEEE from cor- processed during this period were HIPS and ABS, which do porations, drop-offs by individuals, and also WEEE that not contain glass fibers and polycarbonate. comes by post. The collection of the waste is carried out by subcontractors using diesel trucks with a maximum capacity 3.2.4 Allocation procedure of approximately 7920 kg of WEEE. To calculate the distance between the collection and the It was necessary to carry out an allocation procedure to split company under investigation, it was considered that, for a the environmental effects among the co-products of the sys- particular city, on a particular day and on the next day, the tem. Plastics were the major products in the studied process, truck collected all the waste in the city and then went to the followed by byproducts such as ferrous metals, glass, and company. In addition, when calculating the diesel consump- aluminum, used in other product systems. The allocation pro- tion, only the percentage of the maximum capacity of the truck cedure was based on mass. used to transport the WEEE to the company was considered, The percentage of plastics (ABS, HIPS, PP, PS, and others) as the subcontracted vehicle may have been transporting loads in the WEEE accounted for approximately 24% of the mate- from other companies in case its maximum capacity had not rials. According to Vilaplana and Karlsson (2008), the weight been reached. The density used to calculate the diesel con- of these plastics corresponds to approximately 20% of the sumption of the vehicle was 0.85 kg/L and the fuel consump- total. tion was 5.6 km/L (Brasil 2014). The CO2 emission due to diesel oil consumption was calculated based on the emission

3.3 Calculation of CO2 emission in the studied process value 2.603 kg CO2/L of diesel (Brasil 2014). WEEE input was approximately 10.88 kg, where 7.06 kg was transported

CO2 emissions were quantified using Eq. (1), based on the by subcontractors and 3.82 kg came through the post and IPCC (2006)—Intergovernmental Panel on Climate Change. through individuals (Table 1).

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Table 1 HIPS consolidated inventory Parameters Unit Amount Source

Input Material resources WEEE transported by subcontractors kg/kg of recycled HIPS pellets 7.06 Primary source WEEE brought in by individuals and post kg/kg of recycled HIPS pellets 3.82 Primary source WEEE arriving in the company kg/kg of recycled HIPS pellets 10.88 Primary source WEEE allocated to the kg/kg of recycled HIPS pellets 9.10 Primary source disassembly/sorting area Plastic WEEE to be ground kg/kg of recycled HIPS pellets 1.43 Primary source HIPS plastic from WEEE to be ground kg/kg of recycled HIPS pellets 0.58 Primary source HIPS plastics for grinding kg/kg of recycled HIPS pellets 0.58 Primary source Ground stocked HIPS plastic kg/kg of recycled HIPS pellets 0.47 Primary source HIPS plastic to be extruded kg/kg of recycled HIPS pellets 1.06 Primary source Diesel oil kg/kg of recycled HIPS pellets 0.01 Primary source Energy MJ/kg of recycled HIPS pellets 8.12 Primary source Output Atmospheric emissions

CO2 kg CO2/kg of recycled HIPS 0.35 Calculated data pellets (Eq. 1) Solid waste Co-products kg/kg of recycled HIPS pellets 1.10 Primary source Extrusion waste kg/kg of recycled HIPS pellets 0.061 Primary source Product HIPS pellets kg/kg of recycled HIPS pellets 1.00 Primary source Others Packaging solid waste kg/kg of recycled HIPS pellets 0.80 Primary source kg/kg of recycled HIPS pellets 0.13 Primary source

The mass allocation factor attributed to plastics that was used was 24.4%

Upon arrival at the company, the WEEE was identified and Previously sorted WEEE plastics were sent for grinding stored into bags. Approximately 9.10 kg of WEEE followed and then for extrusion according to customer demand. to the disassembly/sorting area and 1.78 kg remained in stock. As this research elaborated two LCIs, one for HIPS and one In the disassembly/sorting stage, the WEEE was separated for ABS, data collection focused on the grinding and extrusion into several components (for example, ferrous metals, glass, stages of the two processed plastics. Table 1, related to HIPS aluminum, aluminum with copper and stainless steel, batte- consolidated inventory, shows that 0.58 kg of HIPS plastics ries). Each component was stored in its respective bag, which was allocated for grinding and 0.85 kg of other plastics (ABS, were weighed and identified after being filled, thus presenting PS, PP, and mixed plastics such as ABS with fiber glass and a cumulative system of materials. Therefore, the amount of polycarbonate) was kept in stock. Since loss in the grinding materials that came out of that area in the period studied had a process is small, the amount of WEEE plastics after grinding higher value than the amount of WEEE sent in to be disman- was considered to be the same as the amount generated in the tled, as the bags already contained some stocked materials. sorting stage. Subsequent to the sorting stage, co-products, solid waste The ground plastics (HIPS and ABS) were sent to the ex- from packaging, and scraps were sent to the final storage area trusion area according to the demand of the company. During for proper environmental disposal. It is important to note that the study period, 0.58 kg of HIPS plastic was ground per some co-products and packaging materials were sold to other kilogram of recycled pellet (Table 1). The amount of 0.47 kg companies, where they were reused or reprocessed. Co- of ground HIPS plastics in stock was added to this value products containing hazardous substances such as batteries resulting in 1.06 kg HIPS plastics, which followed for and monitors were sent to specialized companies for treatment extrusion. and/or appropriate disposal, whereas scraps were donated to Input in the extrusion stage consisted of ground WEEE specialized companies for incineration and energy generation. plastics, energy, water, and mineral oil used in the extruder.

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In the inventory (Table 1), the consumption of water and min- quantify the key factors that account for environmental as- eral oil were not quantified, as the water used in the process pects, such as energy consumption, solid waste, and atmo- works under a closed system, passing through a cooling tower, spheric emissions generated during the data collection period. and because the oil had not been changed up to the moment considered. After extrusion, the plastic pellets were conveyed to the 4.2 Input and output analysis of the system final storage area and sold according to the planning of the company. 4.2.1 Raw material: WEEE The co-products (ferrous metals, glass, aluminum, alumi- num with copper and stainless steel, etc.) were also allocated WEEE corresponds to the input chain of the system under to the final storage area to be sent to a specialized company for study and may be considered raw material for obtaining the treatment. end products—pellets of HIPS and ABS plastic. All other materials (co-products, plastic pellets, solid waste The Brazilian Policy on Solid Waste states that reverse from packaging, extrusion waste, and scrap) followed for final logistics for this type of waste must be conducted through their storage to be dispatched according to the demand of the com- proper disposal and treatment, and thus, an increase in the pany. It is in this area that the pressing process of cardboard, return of these materials is expected. packaging plastics, foam, and Styrofoam solid waste took In addition, the volume of WEEE collected is expected to place. increase due to awareness campaigns aimed at the population, Tables 1 and 2 show the consolidated inventories consid- which deal with the proper disposal and treatment of WEEE. ering the functional unit of 1 kg HIPS pellets and 1 kg of ABS The company conducted a project in partnership with the pellets, respectively. Federal University of Sao Carlos/Sorocaba Campus (Brazil) Based on the consolidated LCIs of the two major recycled for the development and implementation of a WEEE collec- plastics, HIPS and ABS, it was possible to identify and tion point prototype (Sigrist et al. 2015).

Table 2 ABS consolidated inventory Parameters Unit Amount Source

Input Material resources WEEE transported by subcontractors kg/kg of recycled ABS pellets 13.01 Primary source WEEE from individuals and post kg/kg of recycled ABS pellets 7.06 Primary source WEEE arriving in the company kg/kg of recycled ABS pellets 20.07 Primary source WEEE that heads to the kg/kg of recycled ABS pellets 17.48 Primary source disassembly/sorting area Plastic WEEE to be ground kg/kg of recycled ABS pellets 2.90 Primary source ABS plastic from WEEE to be ground kg/kg of recycled ABS pellets 1.29 Primary source Ground ABS plastic kg/kg of recycled ABS pellets 1.29 Primary source ABS plastic from WEEE to be extruded kg/kg of recycled ABS pellets 1.08 Primary source Diesel oil kg/kg of recycled ABS pellets 0.02 Primary source Energy MJ/kg of recycled ABS pellets 9.01 Primary source Output Atmospheric emissions

CO2 kg CO2/kg of recycled ABS 0.41 Calculated data pellets (Eq. 1) Solid waste Co-products kg/kg of recycled ABS pellets 2.17 Primary source Extrusion waste kg/kg of recycled ABS pellets 0.08 Primary source Product ABS pellets kg/kg of recycled ABS pellets 1.00 Primary source Others Packaging solid waste kg/kg of recycled ABS pellets 1.57 Primary source Scrap kg/kg of recycled ABS pellets 0.25 Primary source

The mass allocation factor attributed to plastics used was 24.4%

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4.2.2 Energy 4.2.4 Atmospheric emissions

Energy was considered an input element and emissions related Toxic air pollutants alter local air quality, whereas non- to energy consumption are shown in Figs. 3 and 4. Figure 3 toxic pollutants cause problems on a global scale, such as shows the energy consumption at each stage of the WEEE global warming and the destruction of the ozone layer. plastic recycling process for HIPS and ABS pellets. This fig- Carbon dioxide (CO2), for example, is a relatively inert ure shows that the extrusion presented a higher consumption gas at ambient conditions and is not harmful to human of energy when compared to other stages. This was due to the health but is the gas that most accounts for global need to operate the extruder at high temperatures for fusion of warming. CO2 emissions to the atmosphere were calculat- the materials in the feeding zone. ed as shown in Section 3. Figure 5 shows the CO2 emis- It is also possible to notice that the stage showing the low- sions for each subsystem of the WEEE plastic recycling est energy consumption was the disassembly/sorting stage, process. The extrusion stage was responsible for most which is when the process is mostly carried out manually. CO2 emissions due to its high energy consumption Yet, this consumption could be even smaller if the conveyor (Fig. 5). Emissions during WEEE transportation to the transporting the sorted WEEE operated only when it reached a company relate to the consumption of diesel by the capacity defined as appropriate to operate. vehicle.

Figure 4 shows the total energy consumption of the studied Figure 6 shows the CO2 emissions of the system studied system compared to the energy consumption of works found and those found in LCA works in the literature—Plastics in the literature on LCA under the cradle-to-gate approach, Europe (2005)andPlasticsEurope(2012)—, which respec- namely Plastics Europe (2005)andPlastics Europe (2012), tively used the cradle-to-gate approach for the production of which studied the production of virgin ABS and HIPS, respec- virgin ABS and virgin HIPS. Recycling HIPS and ABS from tively. By looking at this figure, it notices that recycling HIPS WEEE emits, respectively, 84 and 87% less CO2 than their and ABS reduces energy consumption by approximately 90% production using virgin material (Fig. 6). Such reduction con- when compared to using virgin materials. These results are tributes to the findings of Oliveira (2012) and ABDI (2013) consistent with the work made by Makenji and Savage that states that recycling materials (PET, aluminum, copper,

(2012), who emphasize that the mechanical recycling of plas- and glass) contributes to the reduction of CO2 emissions into tics saves over 80% of energy compared to the production of the atmosphere. virgin plastic. 4.2.5 Solid waste/others

4.2.3 Water All solid waste generated in the process (co-products, waste from packaging, scrap, and extrusion waste) were properly Water is used for heating and cooling in the extrusion process. It allocated through recycling processes, reuse or reprocessing, is used to give recycled plastic fillets and heat exchangers a Bcold and avoiding negative impacts on the environment and human bath^ in the heating area of the extruder. After use, it passes health. Scraps were donated to specialized companies for in- through the cooling tower and then returns to the process. cineration and power generation, and waste from the extruder Therefore, it operates in a closed circuit, avoiding effluents. that was not reprocessed was sold as mixed plastics.

Fig. 3 Energy consumption in HIPS and ABS recycling stages. Source: author, 2015

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Fig. 4 Energy: LCI of the HIPS and ABS recycling × literature data on the production of virgin HIPS/ABS. Source: author, 2015

Fig. 5 CO2 emission in each stage of WEEE plastic recycling for HIPS and ABS. Source: author, 2015

As described by Ongondo et al. (2011), Barba-Gutiérrez this stage operates in a closed circuit, thereby causing no dam- et al. (2008), and Rodrigues (2007), the WEEE cause environ- age to the environment. mental impacts when disposed in landfills. However, these impacts were not considered in the present study, since these 4.2.7 Recycled ABS and HIPS pellets are properly disposed. The output chain of the products consisted in the plastic pellets generated in the system, i.e., HIPS and ABS. The results of 4.2.6 Effluents this study show that recycling plastics is beneficial to the environment. This is consistent with other studies, like The extrusion stage was verified to be the only subsystem in Wager and Hischier (2015). The authors report that the ana- the plastic recycling process that uses water. The water used in lyzed environmental impacts were approximately four times

Fig. 6 CO2 emissions: LCI of HIPS and ABS recycling × literature data relative to the production of virgin HIPS/ABS. Source: author, 2015

Content courtesy of Springer Nature, terms of use apply. Rights reserved. Int J Life Cycle Assess (2017) 22:1957–1968 1967 lower when WEEE plastics were recycled instead of being By comparing the system studied with the virgin produc- incinerated and approximately six to ten times lower when tion of ABS and HIPS, it was possible to determine that the compared to the production of virgin plastics. This demon- studied system saves about 90% of energy by recycling HIPS strates the importance of recycling for the environment and and ABS and emits 84% less CO2 into the atmosphere by human health. recycling HIPS and 87% by recycling ABS. The percentage of plastics (ABS, HIPS, PP, PS, and others) By using the LCA tool, this study helped to determine the present in WEEE corresponded to 24% during the period LCI (in order to identify and quantify the environmental as- studied. According to Vilaplana and Karlsson (2008), the total pects) and to collect important information for decision-mak- weight of these plastics present in WEEE corresponds to ap- ing. Therefore, it is extremely important for the calculation of proximately 20%. environmental impacts and for obtaining primary data on As verified by Tanskanen (2013) and Cui and Forssberg WEEE plastic . (2003), the recycling process of WEEE reduced the consump- In order to increase the return of WEEE, the university, tion of natural resources and energy due to the reuse of these alongside the company, intends to develop optimization materials. This provides a saving of resources because it was models for the transportation of such waste by establishing a not necessary to carry out extractive activities to produce vir- route management and the management of the WEEE collect- gin raw materials. The recycled ABS and HIPS pellets are sold ed, thereby reducing the consumption of diesel and conse- and processed into new products with the same function, as quently reducing CO2 emissions into the atmosphere. printer parts, computers, and mobile phone. Acknowledgements We thank the company under study (SINCTRONICS) for their openness and trust in us to conduct this study on their production process. We also thank the Coordination for the Improvement of Higher Education Personnel (CAPES) for the master’s 5Conclusions grant scholarship to J. M. Campolina and the São Paulo Research Foundation (FAPESP) for the scientific research scholarship given to Through life cycle inventories of WEEE plastic recycling C.S.L. Sigrist in the 2013/21573-9 process. using the life cycle assessment tool, it was possible to identify and quantify some environmental aspects generated in each stage of the system studied, such as gas emissions and energy References consumption. 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