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Consumer markets have questioned the use of plastics in packaging because of their environmental impact, and alternative, bio-based films are being developed for this purpose. This study employs Life Cycle Assessment to analyze the environmental and energy performances of producing cassava starch-based film made from casting in Brazil. Results indicate that impacts are mainly caused by the cassava crops, the film manufacture, and the fossil glycerin and ethanol additives used. Resource efficiency and cleaner production measures were devised to reduce the environmental and energy impacts of the product. In terms of energy, an arrangement using both renewable glycerin and biofilm made by extrusion combining cassava starch and polyethylene was shown to be an adequate option to reduce impact. The use of sugarcane ethanol led to an increase in impact for most of the analyzed categories. On the other hand, if the carbon balance considers both carbon dioxide sequestration and biogenic carbon dioxide emissions, the use of renewable alcohol leads to lower impact in Climate Changes. This systemic analysis also allowed for the identification of trade-offs in terms of environmental impacts when considering cultivating and processing cassava in other sites.

Department of Environmental Engineering Campus Experimental de Sorocaba Universidade Estadual Paulista, Sorocaba, Sao Paulo

Post-consumer cooking oil and soft drink PET bottles (PEToil and PETsoft drink) were ground and washed only with water (conventional washing). The polymer was then chemically washed (10 min in an aqueous solution of sodium hydroxide 5 mol·L−1 at 90°C) and rinsed. The materials before and after chemical washing were characterized by intrinsic viscosity, differential scanning calorimetry, thermogravimetry, elemental analysis, scanning electron microscopy with X-ray spectrum microanalysis, and gas chromatography coupled to mass spectrometry. The results indicated that conventionally washed PEToil is the material that most differs among the four tested ones, and that the other three are more similar to each other and to what is expected for pure PET. For example, the composition of PEToil washed only in water contained 30 volatile organic compounds, 5 nonvolatile compounds, and 7 metals, while PETsoft drink washed conventionally and chemically contained 5 volatile organic compounds and no metal or nonvolatile...

This study presents the laboratory scale results of an extra step in Poly (ethylene terephthalate) – PET mechanical recycling (grinding, washing, drying and reprocessing): a chemical washing after the conventional one. Cooking oil PET bottle flakes were washed in water and then subjected to a reaction with an aqueous solution of sodium hydroxide 5 M at 90 °C for 10 min (chemical washing). After rinsing and drying, the flakes were characterized by thermogravimetry, gas chromatography and elemental analysis tests. The results indicated that the chemically washed material had higher purity than PET washed only with water: 99.3% and 96.7%, respectively, which undoubtedly implies properties, applications and prices closer to those of virgin resin. The production of purified terephthalic acid (TPA) from the chemical washing residue was optimized and reached a purity of 99.6%. Despite the results, the use of chemically washed PET and of TPA obtained is not recommended for direct contact with food, since they still contain some impurities.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:01:48Z No. of bitstreams: 1 S0104-14282008000400006.pdf: 124141 bytes, checksum: 2c38712da8c151d86c681b1d6fc26cc9 (MD5) Made available in DSpace on 2013-08-22T19:01:48Z (GMT). No. of bitstreams: 1 S0104-14282008000400006.pdf: 124141 bytes, checksum: 2c38712da8c151d86c681b1d6fc26cc9 (MD5) Previous issue date: 2008-01-01 Made available in DSpace on 2013-09-30T20:02:10Z (GMT). No. of bitstreams: 2 S0104-14282008000400006.pdf: 124141 bytes, checksum: 2c38712da8c151d86c681b1d6fc26cc9 (MD5) S0104-14282008000400006.pdf.txt: 41355 bytes, checksum: 8acce1c56d046ca4c90eb0fb9691762e (MD5) Previous issue date: 2008-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:15:56Z No. of bitstreams: 2 S0104-14282008000400006.pdf: 124141 bytes, checksum: 2c38712da8c151d86c681b1d6fc26cc9 (MD5) S0104-14282008000400006.pdf.txt: 41355 bytes, checksum: 8acce1c56d046ca4c90eb0fb9691762e (MD5) Made available in DSpace on 2014-05-20T15:15:56Z (GMT). No. of bitstreams: 2 S0104-14282008000400006.pdf: 124141 bytes, checksum: 2c38712da8c151d86c681b1d6fc26cc9 (MD5) S0104-14282008000400006.pdf.txt: 41355 bytes, checksum: 8acce1c56d046ca4c90eb0fb9691762e (MD5) Previous issue date: 2008-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Filmes de polipropileno (PP) e de polietilenos de alta (HDPE) e baixa densidades (LDPE) foram estudados avaliando-se a presença de impurezas e o efluente da lavagem de seus resíduos provenientes tanto de coleta comum (resíduos misturados) quanto seletiva (resíduos separados). Os resultados apontam que os filmes estavam impregnados com, no mínimo, 30% de impurezas quando provenientes de coleta comum e com, no máximo, 10% quando de coleta seletiva. Esses resultados, associados aos da turbidez do efluente de lavagem, indicam que dos filmes de coleta seletiva, preferidos pelos recicladores, se obtém pelo menos 20% mais material e tem-se uma lavagem mais fácil, por envolver praticamente só a retirada de sólidos, ao contrário da coleta comum, associada a resíduos úmidos impregnados. Os efluentes foram também avaliados segundo sólidos totais, sólidos sedimentáveis e o teor de nove metais. Os resultados indicaram que os dois tipos de coleta geram efluentes semelhantes e que no máximo duas etapas devem ser suficientes para seus tratamentos: decantação e diluição do efluente no corpo d'água receptor. Polypropylene (PP), high density polyethylene (HDPE) and low density polyethylene (LDPE) films were studied according to the way their wastes are collected (segregated from or mixed with other residues) by evaluating the amount of impurities and the washing wastewater. It was found that the films from mixed collection presented at minimum 30% of impurities, while the films from segregated (or curbside) collection presented at maximum 10% of impurities. The amount of impurities and the wastewater turbidity indicated that 20% more material can be obtained from the films of segregated colletion, preferred by recyclers, in addition to having a simpler washing process because it only involves solids removal, unlike mixed collection which is associated with the impregnation of wet wastes. The effluents were also evaluated according to the total amount of solids, sediments and concentration of nine metals. The results showed that both types of collection generated similar wastewaters and their treatment requires two steps at the most: sedimentation and effluent dilution in the water body. UNESP Engenharia Ambiental UNESP Engenharia Ambiental

The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of São Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000 kg day—1. A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks.