Recycling in buildings: an LCA case study of a thermal insulation panel made of polyester fiber,recycled from post-consumer PET bottles

Background, aim, and scope  

The interest in polyethylene terephthalate (PET) recycling is quite recent, but it has been growing steadily over the past few years. In this context, the aim of this paper is to assess the eco-profile, the energy savings and the environmental benefits of the use of recycled raw materials to manufacture products for thermal insulation of buildings in Italy (i.e., PET bottles post-consumer).     

Life-cycle assessment of domestic and transboundary recycling of post-consumer PET bottles

Background, aim, and scope  

In recent years, besides being recycled domestically, a part of Japanese post-consumer polyethylene terephthalate (PET) bottles have been exported to and recycled in mainland China. In this study, life-cycle assessment (LCA) was applied to compare domestic and transboundary recycling scenarios between Japan and China and disposal scenarios from the viewpoints of greenhouse gases (GHG) emission and fossil resource consumption.     

Life cycle environmental impacts of carbonated soft drinks

Purpose

The UK carbonated drinks sector was worth £8 billion in 2010 and is growing at an annual rate of 4.9 %. In an attempt to provide a better understanding of the environmental impacts of this sector, this paper presents, for the first time, the full life cycle impacts of carbonated soft drinks manufactured and consumed in the UK. Two functional units are considered: 1 l of packaged drink and total annual production of carbonated drinks in the UK. The latter has been used to estimate the impacts at the sectoral level. The system boundary is from ‘cradle to grave’. Different packaging used for carbonated drinks is considered: glass bottles (0.75 l), aluminium cans (0.33 l) and polyethylene terephthalate (PET) bottles (0.5 and 2 l).

Materials and methods

The study has been carried out following the ISO 14040/44 life cycle assessment (LCA) methodology. Data have been sourced from a drink manufacturer as well as the CCaLC, Ecoinvent and Gabi databases. The LCA software tools CCaLC v2.0 and GaBi 4.3 have been used for LCA modelling. The environmental impacts have been estimated according to the CML 2001 method.

Results and discussion

Packaging is the main hotspot for most environmental impacts, contributing between 59 and 77 %. The ingredients account between 7 and 14 % mainly due to sugar; the manufacturing stage contributes 5–10 %, largely due to the energy for filling and packaging. Refrigeration of the drink at retailer increases global warming potential by up to 33 %. Transport contributes up to 7 % to the total impacts.

Conclusions

The drink packaged in 2 l PET bottles is the most sustainable option for most impacts, including the carbon footprint, while the drink in glass bottles is the worst option. However, reusing glass bottles three times would make the carbon footprint of the drink in glass bottles comparable to that in aluminium cans and 0.5 l PET bottles. If recycling of PET bottles is increased to 60 %, the glass bottle would need to be reused 20 times to make their carbon footprints comparable. The estimates at the sectoral level indicate that the carbonated drinks in the UK are responsible for over 1.5 million tonnes of CO₂ eq. emissions per year. This represented 13 % of the GHG emissions from the whole food and drink sector or 0.26 % of the UK total emissions in 2010.     

Comparative life cycle assessment and social life cycle assessment of used polyethylene terephthalate (PET) bottles in Mauritius

Purpose

Improper disposal of used polyethylene terephthalate (PET) bottles constitute an eyesore to the environmental landscape and is a threat to the flourishing tourism industry in Mauritius. It is therefore imperative to determine a suitable disposal method of used PET bottles which not only has the least environmental load but at the same time has minimum harmful impacts on peoples employed in waste disposal companies. In this respect, the present study investigated and compared the environmental and social impacts of four selected disposal alternatives of used PET bottles.

Methods

Environmental impacts of the four disposal alternatives, namely: 100 % landfilling, 75 % incineration with energy recovery and 25 % landfilling, 40 % flake production (partial recycling) and 60 % landfilling and 75 % flake production and 25 % landfilling, were determined using ISO standardized life cycle assessment (ISO 14040:2006) and with the support of SimaPro 7.1 software. Social life cycle assessments were performed based on the UNEP/SETAC Guidelines for Social Life Cycle Assessment of products. Three stakeholder categories (worker, society and local community) and eight sub-category indicators (child labour, fair salary, forced labour, health and safety, social benefit/social security, discrimination, contribution to economic development and community engagement) were identified to be relevant to the study. A new method for aggregating and analysing the social inventory data is proposed and used to draw conclusions.

Results and discussion

Environmental life cycle assessment results indicated that highest environmental impacts occurred when used PET bottles were disposed by 100 % landfilling while disposal by 75 % flake production and 25 % landfilling gave the least environmental load. Social life cycle assessment results indicated that least social impacts occurred with 75 % flake production and 25 % landfilling. Thus both E-LCA and S-LCA rated 75 % flake production and 25 % landfilling to be the best disposal option.

Conclusions

Two dimensions of sustainability (environmental and social) when investigated using the Life Cycle Management tool, favoured scenario 4 (75 %?% flake production and 25 % landfilling) which is a partial recycling disposal route. One hundred percent landfilling was found out to be the worst scenario. The next step will be to explore the third pillar of sustainability, economic, and devise a method to integrate the three dimensions with a view to determine the sustainable disposal option of used PET bottles in Mauritius.     

PET bottle reverse logistics—environmental performance of California’s CRV program

Purpose

Disposable beverage bottles made of polyethylene terephthalate (PET) stand in sharp contrast to many other disposable plastic packaging systems in the US for their high level of post-consumer recovery for recycling. This is due in part to container deposit programs in several US states, such as the California Redemption Value (CRV) program. We investigate the impacts of PET bottle recycling in the CRV program to evaluate its effectiveness at reducing environmental burdens.

Methods

We develop a life cycle model using standard process LCA techniques. We use the US LCI database to describe the energy production infrastructure and the production of primary materials. We describe the inventory and logistical requirements for materials recovery on the basis of state-maintained statistics and interviews with operators and industry representatives. We report inventory indicators describing energy, freight, and waste disposal requirements. We report several impact indicators based on CML and TRACI-2.0 techniques. We apply system expansion to compare post-consumer activities to produce secondary polymer against equivalent primary production.

Results and discussion

While bottle collection is distributed across the state, processing is more centralized and occurs primarily near urban centers. The average distance traveled by a bottle from discard to recovery is 145–175 km. Recycling requires 0.45–0.66 MJ of primary energy/L of beverage, versus 3.96 MJ during the pre-consumer phase. Post-consumer environmental impacts are significantly lower than pre-consumer impacts, with the exception of eutrophication. The results are robust to model sensitivity, with allocation of fuel for bottle collection being the most significant parameter. Curbside collection is slightly more energy efficient than consumer drop-off, and is subject to smaller parametric uncertainty. Recycling has the potential for net environmental benefits in five of seven impact categories, the exceptions being smog (marginal benefits) and eutrophication (increased impacts).

Conclusions

California’s decentralized program for collecting and processing PET bottles has produced a system which generates a large stream of post-consumer material with minimal environmental impact. The selection of a reclamation locale is the most significant factor influencing post-consumer impacts. If secondary PET displaces primary material, several environmental burdens can be reduced.

Recommendations and perspectives

Our results suggest that deposit programs on disposable packaging are an effective policy mechanism to increase material recovery and reduce environmental burdens. Deposit programs for other packaging systems should be considered.     

Multicriteria Design of Plastic Recycling Based on Quality Information and Environmental Impacts

In this study, we develop a framework for the multicriteria design of plastic recycling based on quality information and environmental impacts for the purpose of supporting collaborative decision making among consumers, municipalities, and recyclers. The subject of this article is the mechanical recycling of postconsumer polyethylene terephthalate (PET) bottles. We present a “quality conversion matrix,” which links the quality of recycled PET resin to the quality of waste PET bottles and operational conditions, described in terms of the functions of modules constituting the entire recycling process. We estimate the quality of recycled PET resin and simulate the applicability to the intended products as the primary criterion by confirming whether the estimated quality of recycled resin satisfies the quality demands of PET resin users. The amounts of carbon dioxide (CO₂) emissions and fossil resource consumption are also estimated as the secondary criteria. An approach to collaborative decision making utilizing mixed‐integer linear programming (MILP) and Monte Carlo simulation is proposed on the premise of different objectives of various stakeholders, where all the feasible optimal solutions for achieving the quality demands are obtained. The quality requirements of waste bottles, along with the CO₂ emissions and fossil resource consumption estimated for each solution, contribute to the collaborative multicriteria design of plastic recycling.     

Évaluation de la TEP au 18F-FDG dans la tuberculose extrapulmonaire : premiers résultats d’une étude pilote observationnelle

Aim

Extrapulmonary tuberculosis treatment is difficult to assess and there is a need for new tools. The aim of this observational pilot study is to evaluate the potential role of 18F-FDG PET/CT in the initial staging and treatment evaluation of extrapulmonary tuberculosis.

Methods

Twenty-eight patients were included between January 2009 and 2010. Twenty-three had a 18F-FDG PET/CT before treatment and/or during and/or after treatment. All patients will be followed for 18 months after the end of treatment. A control group of five patients with previous history of tuberculosis was also included and PET/CT was performed.

Results

Three cases of differential diagnosis were excluded of the study. The initial PET for staging showed additional lesions in 8/10 patients compared to conventional imaging. At the end of treatment, 6/11 patients had a negative PET, and 5/11 patients had a positive PET. PET had a significant clinical impact for 3/10 patients at initial staging (guiding biopsy or increase of planned treatment duration), and for 3/16 during follow up (extend or early interruption of the treatment). All PET scans in the control group were negative.

Conclusion

18F-FDG PET has an excellent sensitivity for the detection of extrapulmonary tuberculosis lesion and excellent negative predictive values. The impact of initial PET staging seems significant. The interest of 18F-FDG PET for the evaluation of response to treatment remains to be assessed and will be correlated with patients’ follow up in a second phase of this study.     

Reliability-based life cycle assessment for future solid waste management alternatives in Portugal

Background, aim, and scope  

This paper presents a study related to the application of the reliability-based life cycle assessment (LCA) to assess different alternatives for solid waste management in the Setúbal peninsula, Portugal. The current system includes waste collection, transport, sorting, recycling, and mechanical and biological treatment (MBT) by means of aerobic treatment and landfill. In addition, some future expansion plans are discussed.     

<Emphasis Type="Italic">In vivo</Emphasis> molecular imaging of experimental joint inflammation by combined <Superscript>18</Superscript>F-FDG positron emission tomography and computed tomography

Introduction  

The purpose of this work was to establish and validate combined small animal positron emission tomography - computed tomography (PET/CT) as a new in vivo imaging method for visualisation and quantification of joint inflammation.     

<Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> β-lactamase induction requires two permeases,AmpG and AmpP

Background  

In Enterobacteriaceae, β-lactam antibiotic resistance involves murein recycling intermediates. Murein recycling is a complex process with discrete steps taking place in the periplasm and the cytoplasm. The AmpG permease is critical to this process as it transports N-acetylglucosamine anhydrous N-acetylmuramyl peptides across the inner membrane. In Pseudomonadaceae, this intrinsic mechanism remains to be elucidated. Since the mechanism involves two cellular compartments, the characterization of transporters is crucial to establish the link.     

The methionine salvage pathway in Bacillus subtilis

Background  

Polyamine synthesis produces methylthioadenosine, which has to be disposed of. The cell recycles it into methionine through methylthioribose (MTR). Very little was known about MTR recycling for methionine salvage in Bacillus subtilis.     

Design of recycling system for poly(methyl methacrylate) (PMMA). Part 1: recycling scenario analysis

Introduction

In this series of papers, we present a poly(methyl methacrylate) (PMMA) recycling system design based on environmental impacts, chemical hazards, and resource availability. We evaluated the recycling system by life cycle assessment, environment, health, and safety method, and material flow analysis.

Purpose

Previous recycling systems have not focused on highly functional plastics such as PMMA, partly because of lower available volumes of waste PMMA compared with other commodity plastics such as polyethylene or polypropylene. However, with the popularization of PMMA-containing products such as liquid crystal displays, the use of PMMA is increasing and this will result in an increase in waste PMMA in the future. The design and testing of recycling systems and technologies for treating waste PMMA is therefore a high research priority. In this study, we analyze recycling of PMMA monomers under a range of scenarios.

Methods

Based on the differences between PMMA grades and their life cycles, we developed a life cycle model and designed a range of scenarios for PMMA recycling. We obtained monomer recycling process inventory data based on the operational results of a pilot plant. Using this process inventory data, we quantified life cycle greenhouse gas (LC-GHG) emissions and fossil resource consumption, and we calculated the LIME single index.

Results and discussion

PMMA produces more than twice the amount of GHG emissions than other commodity resins. Through scenario and sensitivity analyses, we demonstrated that monomer recycling is more effective than mechanical recycling. Operational modifications in the monomer recycling process can potentially decrease LC-GHG emissions.

Conclusions

Highly functional plastics should be recycled while maintaining their key functions, such as the high transparency of PMMA. Monomer recycling has the potential to achieve a closed-loop recycling of PMMA.     

Asymmetric localization of <Emphasis Type="Italic">Arabidopsis</Emphasis> SYP124 syntaxin at the pollen tube apical and sub-apical zones is involved in tip growth

Background  

The continuous polarized vesicle secretion in pollen tubes is essential for tip growth but the location of endo- and exocytic sub-domains remains however controversial. In this report we aimed to show that Arabidopsis thaliana syntaxins are involved in this process and contribute to spatially define exocytosis and membrane recycling.     

MtnK, methylthioribose kinase, is a starvation-induced protein in Bacillus subtilis

Background  

Methylthioadenosine, the main by-product of spermidine synthesis, is degraded inBacillus subtilisas adenine and methylthioribose. The latter is an excellent sulfur source and the precursor of quorum-sensing signalling molecules. Nothing was known about methylthioribose recycling in this organism.     

LCI modelling approaches applied on recycling of materials in view of environmental sustainability,risk perception and eco-efficiency

Purpose and scope  

Two ISO-compliant approaches on modelling the recycling of plastics and metals are frequently applied in life cycle assessment case studies and intensively debated: the recycled content or cutoff approach and the end of life recycling or avoided burden approach. This paper discusses the two approaches from three different perspectives: (1) the kind of sustainability concept served, (2) the risk perception involved and (3) the eco-efficiency indicators resulting from the two approaches.     

Single group study to evaluate the feasibility and complications of radiofrequency ablation and usefulness of post treatment position emission tomography in lung tumours

Background  

There is genuine need to develop interventional treatment options for management of lung tumors. Radiofrequency ablation (RFA) is one such alternative being promoted to treat lung tumors recently. Larger studies should help define RFA's further development. Furthermore fluorodeoxyglucose positron emission tomography (PET) has been reported to be an accurate indicator of treatment response in variety of tumors. This study focuses on the evaluating the feasibility of RFA and usefulness of PET scan in lung tumors after RFA procedure.     

Life cycle assessment of alternatives for recycling abroad alkaline batteries from Portugal

Purpose

The European legislation establishes collection rates and states that all identifiable batteries must undergo treatment and recycling. Due to the inexistence in Portugal of recycling plants for alkaline batteries, those collected there have been sent to Austria and France, and currently, it is pondered to send them to Spain. This study aims to know the potential environmental impacts associated with the management of spent domestic alkaline batteries from collection in continental Portugal to recycling abroad.

Methods

Three alternative recycling processes are considered: in Austria (A), France (F) and Spain (S). The system in study, from battery collection in continental Portugal to recycling abroad, includes complementary processes necessary for this circuit such as the production of boxes for battery collection and/or transportation and, for easiness of analysis and interpretation, is divided into: (i) container manufacture; (ii) distribution of empty containers; (iii) battery collection and sorting; (iv) international transport for the recycling; and (v) battery recycling. Recovered materials were also quantified. The LCA methodology and the method of impact assessment Eco-indicator 99, Hierarchist version, with two options, with and without inclusion of long-term emissions, were used. This method considers three damage categories: human health, ecosystem quality and resources, which group 11 impact categories.

Results and discussion

For ecosystem quality, there is a preponderance of the impact of recycling processes F and S regarding all other processes and, in particular, regarding recycling process A. After these, the container production impact is the most significant followed by the transport to Austria. For human health, there is a preponderance of the impact of recycling process S followed by the impact of F, and then of the transport to Austria and, only after, the impact of recycling process A. For resources, process S impact is higher than the one of A and this is higher than system F. The transport shows an expectable impact (highest for Austria, lowest for Spain), but for Austria and for France, it is higher than the impact of the recycling process itself.

Conclusions

System F is the most negative in terms of ecosystem quality and S is the worst in terms of human health. In these two damage categories, system A is the best but the worst in the damage category of resources, where F is the best system. If the recovered materials are considered in this balance, the environmental advantage of system A is clear.     

Cancer thyroïdien de souche folliculaire avec persistance d’anticorps antithyroglobuline : signification pronostique et apport de la TEP/TDM au F-FDG

Aim

To investigate the rate of persistence or/and recurrence of follicular cell-derived thyroid cancer with elevated serum antithyroglobulin antibody (TgAb) one year after ablative therapy. We also evaluated the predictive factors of persistence or/and recurrence and the clinical impact of PET/CT with FDG.

Methods

This retrospective study involved 154 TgAb+ patients. PET/CT was performed in 22 patients with a pejorative anatomo-clinical type. The results of the PET/CT were compared with histology and clinical follow-up.

Results

In 23 cases, thyroglobulin (Tg) was positive (14% of TgAb+ Tg+) while in other 131 cases, stimulated Tg was negative (86% of TgAb+ Tg−). Twenty-nine patients (18%) were finally diagnosed with persistent or recurrent disease during follow-up. Independent predictive factors were: age higher than 60 years, Tg+, increase of TgAb concentration in the first year following surgery, and T3/T4/N1 status. PET/CT showed sensitivity of 66% and specificity of 90%. Positivity of PET/CT was significantly associated with a poor prognosis.

Discussion and conclusion

There is no significant association between persistence of TgAb and persistent/recurrent disease when stimulated Tg is negative. An increase of TgAb concentration in the first year of follow-up is an important prognostic indicator. PET/CT with FDG seems to be very useful in the therapeutic management of differentiated thyroid cancer, especially for the patients with pejorative anatomo-clinical types.