Toxicity measurement techniques for building materials with wastes

The innovative Horizon 2020 program sponsored by the European Union (EU) aims to promote and develop processes of waste integration in construction materials. However, several potential health hazards caused by building materials have been identified and, there-fore, there is an ongoing need to develop new recycling methods for hazardous wastes and effi-cient barriers in order to prevent toxic releases from the new construction solutions with wastes. This paper presents an overview that focus on two main aspects: the identification of the health risks related to radioactivity and heavy metals present in building materials and identification of these toxic substances in new construction solutions that contain recycled wastes. Different waste materials were selected and distinct methodologies of toxicity evaluation are presented to analyse the potential hazardous, the feasibility of using those wastes and the achievement of op-timal construction solutions involving wastes.

Can oil, plastic and RAP wastes have a new life in novel asphalt mixtures?

The pavement recycling allows to reuse reclaimed asphalt pavement (RAP) or other waste materials in new asphalt mixtures for road construction or rehabilitation, thus re-ducing the use of virgin materials (aggregates and bitumen). Thus, the main aim of this study is to minimize the use of natural resources through the reuse of three waste materials: HDPE, mo-tor oil and RAP. Different amounts of waste motor oil and HDPE were added to an asphalt binder with 50% aged bitumen. The best solutions to produce the modified binders (4.5 to 5.0% HDPE and 10 % waste motor oil) performed as well as a conventional bitumen although they only used 35 % of virgin bitumen. Asphalt mixtures with 50 % RAP were produced with the selected modified binders, improving some characteristics in comparison with conventional asphalt mixtures. In conclusion, these wastes can revive in new asphalt mixtures.

Evaluation of foamed bitumen efficiency in warm asphalt mixtures recycling

The recycling of pavements is nowadays a very important question to the road paving industry. With the objective of incorporating higher percentages of reclaimed asphalt (RA) materials in recycled asphalt mixtures, new techniques have been developed in the last years. The use of foamed bitumen is normally associated with the production of cold asphalt mixtures, which usually show lower quality standards. However, the objective of the work presented in this paper is to assess the use of foamed bitumen as the binder of warm asphalt mixtures incorporating 30% RA, which have quality standards similar to those of conventional mixtures. Thus, five mixtures have been produced with 30% RA, one of them with a conventional bitumen (control mix) and the others with foamed bitumen at different production temperatures. The mixtures were tested for compactability and water sensitivity and the results show a possible reduction of 25 ºC in the production temperatures, while the water sensitivity test results were kept close to 90 %.

A decision support system for a waste collection vehicle routing problem

The selective collection of municipal solid waste for recycling is a very complex and expensive process, where a major issue is to perform cost-efficient waste collection routes. Despite the abundance of commercially available software for fleet management, they often lack the capability to deal properly with sequencing problems and dynamic revision of plans and schedules during process execution. Our approach to achieve better solutions for the waste collection process is to model it as a vehicle routing problem, more specifically as a team orienteering problem where capacity constraints on the vehicles are considered, as well as time windows for the waste collection points and for the vehicles. The final model is called capacitated team orienteering problem with double time windows (CTOPdTW).We developed a genetic algorithm to solve routing problems in waste collection modelled as a CTOPdTW. The results achieved suggest possible reductions of logistic costs in selective waste collection.

Recycled asphalt mixtures produced with high percentage of different waste materials

The use of sustainable solutions in construction is not just an option, but is increasingly becoming a need of the Society. Thus, nowadays the recycling of waste materials is a growing technology that needs to be continuously improved, namely by researching new solutions for waste valorisation and by increasing the amount of wastes reused. In the paving industry, the reuse of reclaimed asphalt (RA) is becoming common practice, but needs further research work. Thus, this study aims to increase the incorporation of RA and other waste materials in the production of recycled asphalt mixtures in order to improve their mechanical, environmental and economic performance. Recycled mixtures with 50% RA were analysed in this study, including: i) RA selection, preparation and characterization; ii) incorporation of other waste materials as binder additives or modifiers, like used motor oil (UMO) and waste high density polyethylene (HDPE); iii) production of different mixtures (without additives; with UMO; with UMO and HDPE) and comparison of their performance in order to assess the main advantages of each solution. With this study it was concluded that up to 7.5 % of UMO and 4.0 % of HDPE can be used in a new modified binder for asphalt mixtures with 50 % of RA, which have excellent properties concerning the rutting with WTS = 0.02 mm/103 cycles, the fatigue resistance with ε6 = 160.4, and water sensitivity with an ITSR of 81.9 %.

Comparative environmental life-cycle analysis of concretes using biomass and coal fly ashes as partial cement replacement material

Nowadays, the concrete production sector is challenged by attempts to minimize the usage of raw materials and energy consumption, as well as by environmental concerns. Therefore, it is necessary to choose better options, e.g. new technologies or materials with improved life-cycle performance. One solution for using resources in an efficient manner is to close the materials' loop through the recycling of materials that result either from the end-of-life of products or from being the by-product of an industrial process. It is well known that the production of Portland cement, one of the materials most used in the construction sector, has a significant contribution to the environmental impacts, mainly related with carbon dioxide emission. Therefore, the study and utilization of by-products or wastes usable as cement replacement in concrete can supply more sustainable options, provided that these type of concrete produced has same durability and equivalent quality properties as standard concrete. This work studied the environmental benefits of incorporating different percentages of two types of fly ashes that can be used in concrete as cement replacement. These ashes are waste products of power and heat production sectors using coal or biomass as fuels. The results showed that both ashes provide a benefit for the concrete production both in terms of environmental impact minimization and a better environmental performance through an increase in cement replacement. It is possible to verify that the incorporation of fly ashes is a sustainable option for cement substitution and a possible path to improve the environmental performance of the concrete industry.

Mechanical analysis of asphalt mixtures produced with waste plastic modified binders

This work compares the viscoelastic properties of an asphalt binder (70/100 pen) modified with different waste plastics and the mechanical properties of the resultant asphalt mixtures. Two different plastic wastes were used, namely recycled HDPE and EVA. Three different polymer modified binders were produced with these plastic wastes: i) 5% HDPE modified binder (P5); ii) 5% EVA modified binder (E5) and; iii) a modified binder with 4% of EVA and 2% HDPE (E4P2). Asphalt mixtures were produced with these modified binders, and their mechanical properties were analysed and compared with a conventional mixture produced with a 30/50 pen bitumen. It was possible to conclude that these recycled polymers are able to improve the mechanical performance of the asphalt mixtures used in road paving.

A mechanical analysis of asphalt recycled mixtures produced with high recycling rates

In this work four asphalt mixtures were compared in terms of mechanical characteristics. One of the mixtures (control mixture) was used as a reference to the study of three mixtures produced with reclaimed asphalt pavement (RAP). One of the recycled mixtures incorporated 30% of RAP and the other two were produced with 50% of RAP. The effect of using a rejuvenator additive (3% rejuvenator) was also evaluated in one of the mixtures with 50% of RAP.

Study of the interaction between asphalt and plastic wastes in new polymer modified binders (PMB)

The aim of this study is evaluating the interaction between several base pen grade asphalt binders (35/50, 50/70, 70/100, 160/220) and two different plastic wastes (EVA and HDPE), for a set of new polymer modified binders produced with different amounts of both plastic wastes. After analysing the results obtained for the several polymer modified binders evaluated in this study, including a commercial modified binder, it can be concluded that the new PMBs produced with the base bitumen 70/100 and 5% of each plastic waste (HDPE or EVA) results in binders with very good performance, similar to that of the commercial modified binder.

Análise da estrutura de mercado de Resíduos de Equipamentos Elétricos e Eletrónicos: REEE em Portugal

Dissertação de mestrado em Economia Industrial e de Empresa

Development of bioplastics from agro-wastes

Poster

Sustentabilidade no Design: uma abordagem aos resíduos limpos das indústrias do calçado

Dissertação de mestrado em Design e Marketing

Processing and characterization of plates made from granulate of waste electrical cables

This article is intended to evaluate the density and the mechanical, acoustic and thermal properties of compression moulded plates composed of granulate from electrical cables wastes. Those cable wastes are the insulation part from the electric cables, and are composed of PVC, PE, EMP and PEX rubber. After these materiais lose their initial properties and cease to be useful as insulation material, due to safety requirements, it is possible to reuse them into new applications like industrial or playground floorings, as sound insulation material to be applied in walls or floors, or to dampen vibrations from equipments. Recovering electric cable waste has been a major concern to the European Commission due to its leveis of toxicity when incineration and land fill ing is the solution to dispose this material. Such as the European Commission's study for DG Xl[1] suggested that recycling may be the most favourable future waste management option.

Lard as a suitable and cheap substrate for microbial lipids production by Yarrowia lipolytica

[Excerpt] Current agricultural and industrial practices have led to the generation of large amounts of various low-value or negative cost crude wastes, which are difficult and economically notattractive to treat and valorize. One important example of waste generation is animal fat, commonly found in tanning process and slaughterhouses. These wastes, in which the lipids are often the main and most problematic components, are not currently used effectively and there are almost no application methods to recover the respective value. (...)