Life cycle assessment of experimental Al-ion batteries for energy storage applications.

In this work, the analysis of environmental performance and its coherence with circular economy priorities of different variants of Al-ion battery construction was performed. Al-ion-based batteries can be considered as one of the future alternatives for currently used Li-ion-based cells when the shortage of lithium or cobalt becomes a challenge. All tested batteries were constructed with Al anodes, polypropylene foil separator, polyvinylidene fluoride + N-Methyl-2-pyrrolidone (PVDF+NMP) binder, Al collector and laminated Al foil pouch cell. WO3, Norit and carbon from potato starch (CPS) were used as a cathode material. Saturated solutions of AlCl3 dissolved in diethylene glycol dimethyl ether (DEG) and deep eutectic solvents (DES) originating from bacterial polymer polyhydroxyalkanoate were used as electrolytes. The ReCiPe impact assessment method was used in this analysis. The indicator in this study was ReCiPe Endpoint (H) V1.07 referring to Europe. SimaPro 9.4 software with Ecoinvent 3.8 inventory database were used for all calculations. The analysis included experimental production and assembly of batteries and their end-of-life processing. Based on the performed analysis it was found that the overall weighted impact of each single construction variant of an Al-ion battery is dominated by the use of electricity, no matter which variant is considered since it is related to the electricity mix in Poland and its high dependence on fossil fuels. Overall environmental impact is the smallest for CPS DEG battery, while Norit DEG and CPS DEG variants have slightly higher impacts. The share of end-of-life processing in overall environmental impacts of all analysed variants was found low compared to the Li-ion batteries. This observation indicates the Al-ion batteries as a promising direction of alternative electrochemical devices for energy storage systems while end-of-life processing and circular solution are concerned.

Findings from a streamlined life cycle assessment of PET-bottles for beverage-packaging applications, in the context of circular economy.

Economic activity, especially production, is based upon the use of natural resources. This is a fact that affects the growing pressure of the need to implement a sustainable approach to the design, manufacture, and disposal of products, as waste management and disposal have a significant impact on the environment. Therefore, the EU waste management policy aims to reduce the impact of waste on the environment and health and improve the efficient use of resources in the EU. The long-term goal of this policy is to reduce the amount of waste generated and, if generation is unavoidable, to promote its use as a resource, increase recycling and ensure safe waste disposal. These and related solutions are critical, given the growing amount of plastic waste. Under this perspective, the aim of the article was to assess the relevant environmental issues in the production of PET bottles for packaging applications, which can enable a significant improvement in the life cycle environmental profile not only of the analysed material but, also, of the downstream systems in which they are used as such or processed for finished, more complex goods. Results highlighted that, due to the largest contribution (nearly 84 %) to the environmental profile of the bottles' life cycle, a substantial improvement could be achieved by replacing 50 % of the total amount of virgin PET used with recycled PET.

A polyhydroxyalkanoates bioprocess improvement case study based on four fed-batch feeding strategies.

The modelling and optimization of a process for the production of the medium chain length polyhydroxyalkanoate (mcl-PHA) by the bacterium Pseudomonas putida KT2440 when fed a synthetic fatty acid mixture (SFAM) was investigated. Four novel feeding strategies were developed and tested using a constructed model and the optimum one implemented in further experiments. This strategy yielded a cell dry weight of 70.6 g l-1 in 25 h containing 38% PHA using SFAM at 5 l scale. A phosphate starvation strategy was implemented to improve PHA content, and this yielded 94.1 g l-1 in 25 h containing 56% PHA using SFAM at 5 l scale. The process was successfully operated at 20 l resulting in a cell dry weight of 91.2 g l-1 containing 65% PHA at the end of a 25-h incubation.

Robust process for high yield conversion of non-degradable polyethylene to a biodegradable plastic using a chemo-biotechnological approach.

In this study, the optimisation of a process for producing medium-chain-length polyhydroxyalkanoate (mcl-PHA) by Pseudomonas putida KT2440 when fed with a polyethene (PE)-derived fatty acid mixture was investigated. The PE was pyrolysed to produce a hydrocarbon wax that was subsequently oxidised to produce a mixture of fatty acids, purified, and used as a PHA substrate for the growth and selection of microorganisms. Based on the shaken flask screening, a production strain, i.e., Pseudomonas putida KT2440, was selected for conducting bioreactor studies. Feeding PE-derived fatty acids in a 20-L setup resulted in high mcl-PHA yields (83.0 g L-1 CDW with 65% PHA in 25 h). Furthermore, life-cycle assessment (LCA) was conducted to determine the environmental advantages of the proposed process and its impacts compared to those of other technologies for treating PE-derived waste streams. We conclude that processing waste PE into PHA, rather than incineration, produces biodegradable material while also reducing the additional emissions that arise from traditional PE waste treatment processes, such as incineration to gain energy.

Identifying the location of odour nuisance emitters using spatial GIS analyses.

The primary objective of the article was to establish the location of odour emitters with the use of spatial GIS analyses. The odour emitter location analysis based on measurements was carried out using QGIS software tools. The algorithm of the procedure was developed by analysing vector elements, including simulated odour streaks (in the form of wedge buffer surfaces) and a regular grid of points needed to determine the presence of a given buffer in a given location. Statistical analysis was performed in ArcGIS software. The detailed aim of the conducted study was to analyse the nuisance of odours from the measurement data on the basis of IDW interpolation and the arrangement of buildings. An innovative element of the developed analysis is the application of the inversed method of fragrance streak propagation. Identifying a streak from the measuring point towards the blowing wind is very likely to determine the approximate location of the odour emitter measured. The described method should provide better results at the location of emitters than the above mentioned methods using interpolation, because of taking into account wind direction and speed. In addition, it is a method that can be applied over a large open area where methods based on simulation and particle propagation would not be efficient or highly impossible to apply due to extensive and complex analysis. It was necessary to conduct field studies in order to meet the main goal, which resulted in sensory evaluation of the intensity of odour nuisance in an urbanised area. Odour concentration tests using field olfactometry with NasalRanger olfactometer were taken.

What Has Been Trending in the Research of Polyhydroxyalkanoates? A Systematic Review.

Over the past decades, enormous progress has been achieved with regard to research on environmentally friendly polymers. One of the most prominent families of such biopolymers are bacterially synthesized polyhydroxyalkanoates (PHAs) that have been known since the 1920s. However, only as recent as the 1990s have extensive studies sprung out exponentially in this matter. Since then, different areas of exploration of these intriguing materials have been uncovered. However, no systematic review of undertaken efforts has been conducted so far. Therefore, we have performed an unbiased search of up-to-date literature to reveal trending topics in the research of PHAs over the past three decades by data mining of 2,227 publications. This allowed us to identify eight past and current trends in this area. Our study provides a comprehensive review of these trends and speculates where PHA research is heading.

How sustainable are biopolymers? Findings from a life cycle assessment of polyhydroxyalkanoate production from rapeseed-oil derivatives.

The main purpose of the article was to compare different scenarios of biopolymer production and their impacts on the environment using Life Cycle Assessment. Three alternative polyhydroxyalkanoates (PHA: amorphous PHA and poly(3-hydroxybutyrate), P(3HB)) production scenarios were considered to assess its environmental impact: Scenario A - Production of mcl-PHA/P(3HB) from crude vegetable oil; Scenario B - Production of P(3HB) with biodiesel by-product; Scenario C - Production of mcl-PHA/P(3HB) from used vegetable oil. Subject to the scenario considered, it was shown that the environmental efficiency of PHA production is highly dependent on carbon sources used, and it is strongly supporting production of mcl-PHA instead of P(3HB). As LCA study shows, due to low yield of P(3HB) in comparison to mcl-PHA production in considered processes, all the P(3HB) production scenarios have higher impacts than the production of mcl-PHA. Production processes based on bacterial fermentation had its impacts related mostly to the raw materials used and to its separation phase. Additionally, using secondary materials instead of raw ones, namely used oil instead of virgin oil, gives significant improvement with regard to environmental impact. The resource efficiency is also the identified as the key factor with sensitivity analysis that indicates the possible increase of biopolymer yield as the most beneficial factor. Biobased polymers have big environmental potential but still need significant improvement with regard to their manufacturing processes in order to become more economically benign. Preferably production of these microbial polymers should be integrated into biorefinery blocks, where such waste stream arises (e.g. biodiesel production plant).