The effects of changes in recycling patterns on United Kingdom resource consumption

Recycling, substitution and product life extension are identified as significant factors contributing to an extension of the time to exhaustion of industrially Dnportant materials. A quantitative assessment of the significance of virtually all materials to the U.K. is made. Copper is identified as one of the most important materials deserving of further investigation into potential resource savings through increased recycling. The other factors listed above are accounted for in the modelling technique employed. United Kingdom copper flows are qualitatively and statistically described for the years 1949 - 1976. Less accurate statistics are developed for 1922 - 1948. Adaptive expectations type causal models of total, unalloyed, and alloyed copper demand are successfully constructed and are used to generate future scenarios. Evidence is demonstrated for a break in the historical link between U.K. copper demand and industrial production. Simple causal models of potential copper scrap supply are constructed and a comparison made with actual old scrap withdrawals. Accurate adaptive expectations type models of total scrap demand are developed, but no conclusion is reached about the price elasticity of scrap demand. Various scenarios of copper goods demand are forecast and their effect on copper scrap demand. The potential to recover up to an extra 100.000 tonnes/year of generally lower grade old scrap is identified. Policy options are examined and the following recommendations made: 1) A total investment of up to £67 million in secondary refining capacity by the year 2000 is needed. 2) The copper scrap content of copper bearing goods should be specified to aid recovery. 3) A U.K. copper scrap buffer stock scheme would be advantageous for the secondary copper industry. Finally the methodology used is summarised for potential application to other materials.

A review of barriers to kerbside recycling household waste in the UK

The aim of this work is to use systematic review methodology to answer the question “What are the current barriers to kerbside recycling of household waste in the UK?” A systematic search of electronic databases and journals was undertaken to identify academic published work. A critical scoping review of research published between 2000 – 2008 profiles theory and research design. The systematic review identified twelve relevant papers, of which seven contain original data. To define the current barriers the explanations of barriers were systematically aggregated into four main categories: household / individual behaviour; services / local situation; attitudes / motivation; information and knowledge. The purpose of the work is to inform future marketing campaigns which will assist the UK to reach the statutory targets of waste diversion. The synthesis will be useful to environmental professionals working in waste authorities and researchers and students. The framework offers an opportunity to develop better marketing and communications strategies to help more people recycle more things more often and will inform future recycling policy development.

Household waste recycling behavior: a market segmentation model

The potential of social marketing has been recognized in the United Kingdom by the Department for Environment, Food and Rural Affairs (DEFRA) as a useful tool for behavioral change for environmental problems. The techniques of social marketing have been used successfully by health organizations to tackle current public health issues. This article describes a research project which explored the current barriers to recycling household waste and the development of a segmentation model which could be used at the local level by authorities charged with waste collection and disposal. The research makes a unique contribution to social marketing through the introduction of a competencies framework and market segmentation for recycling behaviors.

A techno-economic study of the recycling of mixed plastics to useful products

The techno-economic implications of recycling the components of mixed plastics waste have been studied in a two-part investigation: (a) An economic survey of the prospects for plastics recycling, the plastics waste arisings from retailing, building, automotive, light engineering and chemical industries have been surveyed by mans of questionnaires and interviews. This was partially successful and indicated that very considerable quantities of relatively clean plastics packaging was available in major department chains and household stores. The possibility of devising collection systems for such sources, which do not lead to any extra cost, have been suggested. However, the household collection of plastics waste has been found to be uneconomic due to high cost of collection, transportation and lack of markets for the end products. (b) In a technical study of blends of PE/PP and PE/PS which are found in admixture in waste plastics, it has been shown that they exhibit poor mechanical properties due to incompatibility. Consequently reprocessing of such unsegregated blends results in products of little technological value. The inclusion of some commercial block and graft copolymers which behave as solid phase dispersants (SPES) increase the toughness of the blends (e.g. EPDM in PE/PP blend and SBS in PE/PS blend). Also, EPDM is found to be very effective for improving the toughness of single component polypropylene. However, the improved Technical properties of such blends have been accompanied by a fast rate of photo-oxidation and loss of toughness due to the presence of unsaturation in SPD's. The change in mechanical properties occurring during oven ageing and ultra-violet light accelerated weathering of these binary and ternary blends was followed by a viscoelastonetric technique (Rheovibron) over 9,, wide range of temperatures, impact resistance at room temperature (20-41'G) and changes in functional groups (i.e. carbonyl and trans-1,4-polybutadiene). Also the heat and light stability of single and mixed plastics to which thiol antioxidants were bound to SPE1 segment have been studied and compared with conventional antioxidants. The long-term performance of the mixed plastics containing SPE1 have been improved significantly by the use of conventional and bound antioxidants. It is concluded that an estimated amount of 30000 tonnes/year of plastics waste is available from department chains and household stores which can be converted to useful end products. This justifies pilot-experiments in collaboration with supermarkets, recyclers and converters by use of low cost SPD's and additives designed to make the materials more compatible.

Waste 4:electronic-scrap recycling

The Haloclean process, a rotary kiln process for pyrolysis, developed by researchers at the Forschungszentrum Karlsruhe, Germany makes it possible to recover copper and precious metals from the scrap, ready for recycling. Pyrolysis neatly turns brominated electronic scrap plastics into recyclable copper and methanol feedstock while removing the halogens. The process has demonstrated its ability to recycle brominated electronic scrap in extensive parametric studies. A method suitable for the selective production of HBr in the presence of chlorine is the treatment of the pyrolysis oils with molten polypropylene. This treatment is offers the possibility to use the gas and liquid fraction from pyrolysis of electronic scrap as fossil fuel substitute in copper smelter processes or as feedstock for methanol production via gasification.

SNX4 coordinates endosomal sorting of TfnR with dynein-mediated transport into the endocytic recycling compartment

SNX-BAR proteins are a sub-family of sorting nexins implicated in endosomal sorting. Here, we establish that through its phox homology (PX) and Bin-Amphiphysin-Rvs (BAR) domains, sorting nexin-4 (SNX4) is associated with tubular and vesicular elements of a compartment that overlaps with peripheral early endosomes and the juxtanuclear endocytic recycling compartment (ERC). Suppression of SNX4 perturbs transport between these compartments and causes lysosomal degradation of the transferrin receptor (TfnR). Through an interaction with KIBRA, a protein previously shown to bind dynein light chain 1, we establish that SNX4 associates with the minus end-directed microtubule motor dynein. Although suppression of KIBRA and dynein perturbs early endosome-to-ERC transport, TfnR sorting is maintained. We propose that by driving membrane tubulation, SNX4 coordinates iterative, geometric-based sorting of the TfnR with the long-range transport of carriers from early endosomes to the ERC. Finally, these data suggest that by associating with molecular motors, SNX-BAR proteins may coordinate sorting with carrier transport between donor and recipient membranes.

Scavenging of halogen in recycling of halogen-based polymer materials

Pyrolytic recycling of materials for electronics and automotive is attractive because of the possibility of recovery of fuel and of precious metals from printed circuit. Due to the complexity of their composition an appropriate pre-treatment has to be performed in order to limit the evolution of dangerous halogen containing compounds which strongly impair the fuel quality. An advantageous pyrolysis approach implies the attempt of mineralisation of the organic bromine to the not volatile and harmless inorganic form using strong bases such as NaOH and KOH to reduce the amount of volatile and increasing the residue. The char stability is greatly variable depending on the substrate. Mg(OH)2 and Ca(OH)2 behave in a similar manner but to a lower extent. Carbonates and reducing agent such as LiAlH have been tested as well and their ability to scavenge bromine is discussed in terms of effectiveness and mechanism.

The resource conservation effect of recycling in a dynamic Leontief model

The aim of the paper is to investigate the impact of recycling on the use of non-renewable resources in the economy. The paper tries to generalize the classical dynamic input–output model. In this regard we extend the standard Leontief model with the balance equation of recycled products, and we establish some properties of this augmented model. We investigate how recycling extends the availability of non-renewable natural resources for the next generations in an inter-industry framework. Supposing a balanced growth both for production and consumption, we examine the existence of the balanced growth path of this model and compare the results to the classical Leontief model. We try to answer the question whether recycling/reuse increases the growth possibility of an economy. Finally, we illustrate our results with a simple numerical example. Thus, we analyze a possible sustainable development of the economy on the basis of the product recovery management of industries.

A production/recycling model with quality consideration

An integrated production–recycling system is investigated. A constant demand can be satisfied by production and recycling. The used items might be bought back and then recycled. The not recycled products are disposed off. Two types of models are analyzed. The first model examines and minimizes the EOQ related cost. The second model generalizes the first one by introducing additionally linear waste disposal, recycling, production and buyback costs. This basic model was examined by the authors in a previous paper. The main results are that a pure strategy (either production or recycling) is optimal. This paper extends the model for the case of quality consideration: it is asked for the quality of the bought back products. In the former model we have assumed that all returned items are serviceable. One can put the following question: Who should control the quality of the returned items? If the suppliers examine the quality of the reusable products, then the buyback rate is strongly smaller than one, α<1. If the user does it, then not all returned items are recyclable, i.e. the use rate is smaller than one, δ<1. Which one of the control systems are more cost advantageous in this case?

A Comparison of the Impacts of Lithium Extraction and Lithium Recycling Processes

Lithium is used in the cathode and electrolyte of rechargeable batteries in many portable electronics and electric vehicles, and is thus seen as a critical component of modern technology (Gruber et al., 2011). Electric vehicles are promoted as a way to reduce carbon emissions associated with the transportation sector, which accounts for 14.3% of anthropogenic greenhouse gas emissions (OECD International Transport Forum, 2010). However, the sustainability of lithium procurement will influence the overall environmental impact of this proposed “green” solution. It is estimated that 66% of the world’s lithium resource is contained in natural brines, 24% in pegmatites, and 8% in sedimentary rocks such as hectorite clays (Gruber et al., 2011). It has been shown that “[r]ecycling of lithium from Li-ion batteries may be a critical factor in balancing the supply of lithium with future demand” (Gruber et al., 2011). In an attempt to quantify energy and materials consumption associated with production of a unit of useful lithium compounds, industry reports and peer-reviewed scientific literature concerning lithium mining and lithium recycling were reviewed and compared. Other aspects of sustainability, such as waste or by-products produced in the production of a unit of useful lithium, were also explored. Thus, this paper will serve to further the evaluation of the comparative environmental consequences associated with lithium production via extraction versus recycling. Efficiencies must be made in both processes to maximize productivity while minimizing ecological harm.

Asphalt cement concrete pavement recycling, Cass and Montgomery Counties : final report for Iowa DOT project HR-1018, Federal Highway Administration demonstration project no. 39, contract no. DOT-FH-15-336, 1986

This demonstration project consisted of three adjacent highway resurfacing projects using asphalt cement concrete removed from an Interstate highway which had become severely rutted.

Evaluation of control devices for asphalt pavement recycling operations : summary report for research project HR-188, 1982

The objective of the research project was to seek acceptable solutions to the air pollution problem created in the asphalt recycling process using modified conventional equipment.

Electrolytic cells for plastic waste recycling

The current project assesses potential molten alloy anodes for Solid Oxide Fuel Cells (SOFC) running on solid waste. A detailed phase diagram study was performed to locate probable anode systems. The molten metal oxide system PbO-Sb2O3 was selected as a possible molten alloy anode for this application. A detailed vapour pressure study of this system was performed. Several cells were fabricated to experimentally assess the electrochemical properties of this system. The work reveals several unexpected limiting features such as the incompatibility between the platinum and the chosen alloy. A second cell was built, this time using rhenium wires instead, preventing such reaction. However, the rhenium wire sublimes under oxidizing conditions (air) and the sealing glass and the chosen alloy system react with each other under long term use. Considering all these issues, a third cell design was conceived, surpassing some obstacles and providing some initial information regarding the electrochemical behaviour. The current project shows that many parameters need to be taken into account to ensure materials compatibility. For the PbOSb2O3 system, the high volatility of Sb2O3 was a serious limitation that can only be addressed through the application of new contact wires or sealing materials and conditions. Nonetheless, the project highlights several other potential systems that can be considered, such as Pb11Ge3O17, Pb3GeO5, Pb5Ge3O11, Bi2CuO4, Bi2PdO4, Bi12GeO20.

Processing traits of European catfish (Silurus glanis Linnaeus, 1758) from outdoor flow-through and indoor recycling aquaculture units

The quality of fish cultured using recycling units may differ from that of fish from outdoor farming units due to a range of deviating environmental determinants. This applies not only to flesh quality but also to morphological (processing) traits. This study evaluates processing yields of sibling fish cultured in two different farming units: (i) an outdoor pond aquaculture system with a flow-through regime (24.6 ± 0.2°C), and (ii) indoor tanks using a recirculation aquaculture system (RAS; 26.0 ± 1.0°C). Clear differences were observed in the most important processing traits, i.e. skinned trunk and fillet yields, which were both significantly higher (P < 0.01) in RAS fish due to significantly smaller (P < 0.05) head weight in fish of the flow-through system. Skin represented a significantly higher (P < 0.01) proportion of total weight in both RAS males and females. The most obvious difference was in the deposited fat weight, which was significantly higher (P < 0.01) in RAS fish. Visceral fat deposits were significantly higher (P < 0.01) in females and ventral and dorsal fat deposits higher (P > 0.05) in males.