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One of the main drawbacks of heterogeneous photocatalysis is the high consumption of electrical energy generated by conventional lamps. This study proposes a methodology to find the best distribution of light emitting diodes (LEDs), i.e., the least amount of elements, and the optimum distance between them in order to substitute conventional lamps in photocatalytic processes, and a performance analysis in terms of energetic efficiency, using for this the Electric energy per order (EEO) Figure-of-merit and the cost results for the degradation of the textile reactive dye Orange PX-2R by means of UV/TiO2 process, using conventional lamps and different geometrical patterns of LED arrays. The obtained experimental results show that it is possible to replace sources of high-energy consumption by UV-LED arrays adapted to the specific needs for a given photocatalytic reactor obtaining suitable oxidation results, and the rate of decolorization obtained is similar to the results obtained with conventional lamps; however the UV-LEDs require 70% less electrical energy (178 vs 628 kWh/m3/order) than UV-lamps. Consequently, the use of UV-LEDs enables to degrade 3.5 times more dye with the current energy consumption of UV lamps. Finally, the proper choice for an array can generate additional energy savings.

The textile industry is one of the largest consumers of water in the world and its wastewater constitutes a serious problem when it is discharged without the proper treatment. Different techniques are being applied for treating textile effluents. But, as far as we know, none of them consider the reuse of the clarified effluents. In this work, a recently developed wastewater system named ECUVal is proposed to treat and subsequently reuse the effluents generated by the dyeing process of a textile mill, which usually have high dyes and salt content. With this system, a reduction of water and salt consumption is achieved and simultaneously the volume of discharged effluents is also reduced. The ECUVal system is based on an electrochemical treatment assisted by UV irradiation. The system is able to remove colour completely. Colour removal efficiencies between 64 and 99% were obtained depending on the intensity applied. Moreover, the treated effluents are reconstituted in the system to be reused in new dyeing processes. Thus, 70% of water and up to 72% of salt reuse was achieved. The chromatic coordinates of fabrics dyed with the treated effluent were evaluated with respect to reference ones. Dyeings performed with reused effluents were in general into the acceptance limit of the textile industry (DECMC(2:1)¿=¿1). Finally, the environmental impact of the wastewater treatment currently performed in the textile companies was compared with respect to the ECUVal treatment by means of life cycle assessment. It was concluded that the use of the system reduces significantly the environmental impact of the textile industry.

Road transportation is heading towards electri fi cation using Li-ion batteries to power electric vehicles o ff ering eight or ten years' warrant. After that, batteries are considered inappropriate for traction services but they still have 80% of its original capacity. On the other hand, energy storage devices will have an important role in the electricity market. Being Li-ion batteries still too expensive to provide such services with economic pro fi t, the idea to reuse a ff ordable electric vehicle batteries for a 2nd life originated the Sunbatt project, connecting the automotive and electricity sectors. The battery reuse is, by itself, a path towards sustainability, but the clean- liness of energy storage also depends on the electricity generation power sources and the battery ageing or lifespan. This paper analyses the rest of useful life of 2nd life batteries on four di ff erent stationary applications, which are: Support to fast electric vehicle charges, self-consumption, area regulation and transmission deferral. To do so, it takes advantage of an equivalent electric battery-ageing model that simulates the battery capacity fade through its use. This model runs on Matlab and includes several ageing mechanisms, such as calendar ageing, C-rate, Depth-of-Discharge, temperature and voltage. Results show that 2nd life battery lifespan clearly depends on its use, going from about 30 years in fast electric vehicle charge support applications to around 6 years in area regulation grid services. Additionally, this study analyses the day-to-day emissions from electricity generation in Spain, and states that grid oriented energy storage applications will hardly o ff er environmental bene fi ts in the nearby future. On the other hand, applications that go by the hand of renewable power sources, such as self-consumption applications, are much more appropriate

Microplastic pollution is a growing environmental concern among the scientific community. These small particles (5 mm) might come from the fragmentation or direct emission of artificial and synthetic polymers. Among them, the microfibers (MF) are one of the most common types of microplastics identified in the environment. On the other hand, the most encountered type of garbage found in clean-up campaigns is the cigarette butts, which contains the smoked filters (SF) and unsmoked rests of tobacco. SFs are hazardous debris but are usually not properly disposed as such, and are composed of15,000 strands that can be detached as MFs. This study aims to evaluate the detachment rate, the acute aquatic toxicity, and the aquatic-, thermooxidative-, and photo-degradability of the MFs generated from SFs. In this way, it was found that SFs detach approximately 100 small MFs (0.2 mm) per day. In a rough estimation, about 0.3 million tons of potential MFs might be annually reaching aquatic environments from this source. Concerning the eco-toxicity, a statistically significant difference was found when MFs are present in the leachate generated by the SFs, where the Daphnia magna EC100 and EC50 were of 0.620 SF/L and 0.017 SF/L, respectively. Finally, the degradability of the SFs was evaluated by applying two methods (ATR-FTIR analysis and gravimetry). In both of them, a low degradability rate was observed. Thus, it may be concluded that MFs from SFs constitute an important source of microplastics, which might partially explain the high concentration of artificial polymers that have been found in the deep-sea sediments. Yet, the correct management of the SFs is an unsolved issue that should receive urgent attention. CAPSULE: This work evaluates the detachment rate, toxicity, and degradability of the microfibers detached from the cigarette butts.

Electric vehicles (EVs) are massively entering the mobility services. However, the high costs of their batteries, and thus of the vehicles, represent a real barrier that refrain consumers from buying EVs. In order to reduce the EV costs, research on recovery battery to be reused in a second life for stationary use is being explored, as it this is expected to decrease the cost of these batteries (second life) is being considered for additional stationary uses. For this purpose, specific conditioning (disassembling and repurposing) activities on the battery need to be undertaken to enable a further use of Li-ion batteries once they have completed their duty life in a vehicle (first life). Since economy matters, the economic aspects of these activities need to be analysed to fully understand the economic feasibility of the second life as a key element to that will determine the success of the implementation of EVs. This paper investigates the current state of art of the disassembling activities by analysing the Smart ForFour Li-ion battery and provides insights of the costs of each disassembling operation, from battery level to cell level. Another key aspect will be the remanufacturing at battery level as it presents some advantages over either module or cell level such as a less time is required and consequently a fewer cost. On the other hand, the reuse at module level presents interesting advantages such as the chance to design more versatile and scalable solutions, which could be more interesting despite their initial drawbacks for many second life applications. Therefore, the disassembling costs will play an important role in the repurposed battery selling prices.

In this work, the environmental performance of the reactive Jet dyeing process and the subsequent wastewater treatment currently carried out in the textile companies is compared with a new system. The developed system combines the application of an electrochemical process with ultraviolet irradiation (EC-UV) to remove colour of effluents containing reactive dyes. EC-UV system is also able to prepare the discoloured effluents for its subsequent reuse in a new dyeing process. The developed system can operate in two modes: decolourisation and decolourisation plus reuse. This study compiles life cycle inventory data for both operation modes and compares their environmental impact with the conventional dyeing and wastewater treatment. The results show that the EC-UV system, running in “decolourisation mode” (ED scenario), has a better environmental performance than conventional decolourisation (CD scenario), since the tertiary treatment is eliminated. The environmental assessment for CD and ED scenarios shows that the dyeing process has the largest contribution to all the impact categories, mainly caused by the consumption of Na2CO3 and NaCl. When EC-UV system is running to treat and reuse water and salt (EDR scenario), the reconstitution step process, necessary to reuse effluents, has a great contribution in most of the impact categories. Based on the obtained results, a modification in the dyeing process has also been evaluated. The proposed modification substitutes the use of Na2CO3 by NaOH in the dyeing process, causing a great environmental improvement in all the impact categories for the EDR scenario, being this scenario the one with better environmental performance.

In this study, three different biological methods&mdash, a conventional activated sludge (CAS) system, membrane bioreactor (MBR), and moving bed biofilm reactor (MBBR)&mdash, were investigated to treat textile wastewater from a local industry. The results showed that technically, MBR was the most efficient technology, of which the chemical oxygen demand (COD), total suspended solids (TSS), and color removal efficiency were 91%, 99.4%, and 80%, respectively, with a hydraulic retention time (HRT) of 1.3 days. MBBR, on the other hand, had a similar COD removal performance compared with CAS (82% vs. 83%) with halved HRT (1 day vs. 2 days) and 73% of TSS removed, while CAS had 66%. Economically, MBBR was a more attractive option for an industrial-scale plant since it saved 68.4% of the capital expenditures (CAPEX) and had the same operational expenditures (OPEX) as MBR. The MBBR system also had lower environmental impacts compared with CAS and MBR processes in the life cycle assessment (LCA) study, since it reduced the consumption of electricity and decolorizing agent with respect to CAS. According to the results of economic and LCA analyses, the water treated by the MBBR system was reused to make new dyeings because water reuse in the textile industry, which is a large water consumer, could achieve environmental and economic benefits. The quality of new dyed fabrics was within the acceptable limits of the textile industry.

Research towards renewable energy sources is of great relevance in the pursue of environmental impact reduction and to decrease the dependency on fossil fuels. In high solar irradiation locations, the use of Concentrating Solar Power technologies might be a good alternative in front of other power sources. This study presents how multi-criteria methods such as the weighted technical analysis are useful to select the best heat transfer fluid to be used in a relatively small Concentration Solar Power plant in the Burkina Faso. To do so it analyzes three aspects, the technical performance of thermal fluids, their environmental impact and their price, giving them different weights to confer more or less relevance according to the idiosyncrasy of the region. To do the technical analysis, this study simulates the heat gain and temperature increase of four heat transfer fluids while passing through a solar parabolic trough. The environmental impact factor is evaluated following the life cycle assessment methodology and the economic factor compares their price in the market. Results show that Dowtherm A is the best choice for Burkina Faso and Marlotherm is the worst, but these results change considerably if the comparison is done in the USA, where the environmental factor gains relevance in contrast to the economic factor.

Membrane bioreactor (MBR) is one of the advanced treatment technologies used in industrial wastewater treatment due to its various advantages over conventional biological processes. Recently, the application of MBR in treatment of textile wastewater has increased significantly with an effective removal of contaminants. Moving bed bioreactor (MBBR) has been efficiently used for the treatment of different municipal and industrial wastewater during the last decades and it is a relatively novel and effective technology applied in textile wastewater treatment. This review paper presents the situation of MBR and MBBR technology for textile wastewater purification under different conditions and collates results of previous studies during the past years about MBR and MBBR treatment technologies used in textile processes. Both of these two technologies have shown their efficiency, but they still have problems in textile wastewater treatment. To this end, MBR-MBBR hybrid system could be an attractive solution for textile wastewater purification because of the high efficiency and low consumption of energy and space

Textile microfibers are one of the most important sources within primary microplastics. These have raised environmental concerns since its recent identification as pollutants. However, there are still no accurate models to assess their contribution to the microplastic pollution. Hence, in this study, a method to estimate the mass flow of microfibers detached from household laundry that reaches aquatic environments has been developed. The method considers a set of parameters related to the detachment of microfibers, which are, basically: (1) the detachment rate of microfibers from different textile garments, (2) the volume of laundry effluents, (3) the percentage of municipal water that has been treated, (4) the type of used-water treatment applied, and, (5) the proportion of front- versus top-loading washing machines. In this way, 0.28 million tons of microfibers per year were estimated to reach aquatic environments, which is approximately half than the last published valuation. Finally, hypothetical situations were simulated to evaluate the reduction of microfibers by the modification of some of the parameters at different levels (consumer, government entities, and industry). Thus, depending on the implanted alternatives, microfibers that reach the aquatic environments could be reduced between 30% and 65%.

Optical brighteners (OBs) are colorless fluorescent dyes, widely used in industry to improve whiteness in materials. Nearly 80% of all OBs in the market are derivatives of stilbene. They absorb the near-ultraviolet light and re-emit most of it in the blue range as visible fluorescence. OBs are commonly applied on textiles, detergents, paper and plastic products, among others. OBs have a low degradation ratio. In biological plants, they can only be partially removed by adsorption into the sludge and a tertiary treatment could be required to fully remove them. Part of them may persist and can be found in river and lake waters. The current work aims to evaluate the effect of the OBs in the bacterial activity of biological wastewater treatment plants. The influence of two commercial OBs (Goldblanc BHA and Leucophor PC) on respiration rate was monitored by means of a semi-continuous electrolytic respirometer, in order to obtain information related to the growth of the biomass and the degradation of the substrate. Their acute toxicity was also determined. It was concluded that the OB effect on bacteria population is variable depending on its chemical structure. Unlike the former, the Leucophor-PC brightener had an impact on the respirometric rate.

There has been an intensive research and development focus on lithium-ion batteries, which have revolutionized the electric vehicle market due to the batteries’ high energy and power density, longer lifespan, and increased safety than compa-rable rechargeable battery technologies. The performance of lithium-ion batteries is achieved by packaging design, electrolyte, and electrodes material’s selection. This study focuses on cathode materials as they currently need to overcome criti-cal challenges. In fact, cathode materials affect energy density, rate capability and working voltage that led to the cathode currently costing twice as much as the anode. For this reason, this study reviews cathode materials for electric vehicle lithium-ion batteries under economic and environmental perspectives to optimize the batteries’ structures and properties. Findings reveal that presently there is no commercially installed battery that can satisfy both, economic and environmental concerns while offering an overall excellent performance.

International audience; In order to assess the effect of mixed pollutants, the influence of different concentration levels of a mixture of metals (Cr, Co, Pb, Mn, Ni, Cu, Zn) on the biodegradation of some PAHs (phenanthrene, fluoranthene, pyrene, benzo[b]fluoranthene and benzo[a]pyrene) in soil samples was evaluated. To do so, groups of microcosms of a natural soil from the region of Sabadell (Barcelona, Spain) were prepared as a reproduction of the native environment at laboratory scale, under controlled conditions. Mixtures of PAHs and metals were carefully selected, according to soil characterization and microbiological growth preliminary assays, and were added to microcosms. These microcosms were analyzed at various times, along two months, to obtain PAHs dissipation time-courses. A first-order kinetic modelling allowed obtaining different rate constants and DT50 values as a function of the metal levels introduced in microcosms. As a general observation, the higher the concentration of metals, the lower the biodegradation of PAHs of 3–4 rings (phenanthrene, fluoranthene and pyrene). On the other hand, no important effect on the biodegradation of higher molecular weight PAHs (benzo[b]fluoranthene and benzo[a]pyrene) was observed at the different concentration levels of metals tested.

This article presents a natural coagulant obtained from Moringa oleifera seeds used to reduce water turbidity. The residue generated by an oil extraction plant from M. oleifera seeds is valuated as coagulant in an automatized water purification plant that needs power supply. The main objective of this study is to find the most suitable and sustainable power supply option with regards to a specific zone of Burkina Faso. This article discusses the possibility to deploy a sustainable system providing water purification and electricity to a village of Burkina Faso. Three scenarios are considered to power up the water purification plant (A: electricity grid, B: diesel generator and C: solar panels supported by second life EV batteries). The environmental impact of these three scenarios is done following the life cycle assessment (LCA) methodology based on energy and resources consumption during the material extraction, elements manufacturing, use and dismantle phases. The less pollutant option for this case in Burkina Faso is the “solar panels supported by second life EV batteries”. In comparison to the other scenarios, this system entails a significant reduction of the environmental impact, mainly in the categories of climate change and fossil depletion.

The reactive dye Cibacron Yellow S-3R was selected to evaluate the feasibility of combining nanofiltration membranes with electrochemical processes to treat textile wastewater. Synthetic dyeing effluents were treated by means of two nanofiltration membranes, Hydracore10 and Hydracore50. Up to 98% of dye removal was achieved. The influence of salt concentration and pH on membrane treatment was studied. The best dye removal yield was achieved at pH 3 in the presence of 60 g/L of NaCl. After the membrane filtration, the concentrate containing high dye concentration was treated by means of an electrochemical process at three different current densities: 33, 83, and 166 mA/cm². Results showed a lineal relationship between treatment time and applied current density. Both permeates and electrochemically-decoloured effluents were reused in new dyeing processes (100% of permeate and 70% of decoloured concentrates). Dyed fabrics were evaluated with respect to original dyeing. Colour differences were found to be into the acceptance range.

An electrochemical treatment (EC) was applied at different intensities to degrade the chromophoric groups of dyes C.I. Reactive Black 5 (RB5) and C.I. Reactive Blue 7 (Rb7) until uncolored species were obtained. Decolorization rate constants of the azo dye RB5 were higher than the phtalocyanine Rb7 ones. In addition, the EC treatment was more efficient at higher intensities, but these conditions significantly increased the generation of undesirable by-products such as chloroform. The combination of EC with UV irradiation (UVEC) drastically minimized the generation of chloroform. The photo-assisted electrochemical treatment was also able to achieve decolorization values of 99%. Finally, mixtures of dyes and surfactants were treated by EC and UVEC. In the presence of surfactants, the decolorization kinetic of dyes was slowed due to the competitive reactions of surfactants degradation. Both methods achieved total decolorization and in both cases, the generation of haloforms was negligible.

Sales of bottled drinking water have shown a large growth during the last two decades due to the general belief that this kind of water is healthier, its flavour is better and its consumption risk is lower than that of tap water. Due to the previous points, consumers are more demanding with bottled mineral water, especially when dealing with its organoleptic properties, like taste and odour. This work studies the compounds that can generate obnoxious smells, and that consumers have described like swampy, rotten eggs, sulphurous, cooked vegetable or cabbage. Closed loop stripping analysis (CLSA) has been used as a pre-concentration method for the analysis of off-flavour compounds in water followed by identification and quantification by means of GC-MS. Several bottled water with the aforementioned smells showed the presence of volatile dimethyl selenides and dimethyl sulphides, whose concentrations ranged, respectively, from 4 to 20 ng/L and from 1 to 63 ng/L. The low odour threshold concentrations (OTCs) of both organic selenide and sulphide derivatives prove that several objectionable odours in bottled waters arise from them. Microbial loads inherent to water sources, along with some critical conditions in water processing, could contribute to the formation of these compounds. There are few studies about volatile organic compounds in bottled drinking water and, at the best of our knowledge, this is the first study reporting the presence of dimethyl selenides and dimethyl sulphides causing odour problems in bottled waters.

In this study, the photoreactivation and the modification of dark repair of E. coli in a simulated secondary effluent were investigated after initial irradiation under different conditions. The simulated solar exposure of the secondary wastewater was followed by exposure to six different low-intensity fluorescent lamps (blacklight blue, actinic blacklight, blue, green, yellow and indoor light) for up to 8 h. When photoreactivation was monitored, blue and green colored fluorescent light led to increased bacterial regrowth. Blacklight lamps further inactivated the remaining bacteria, while yellow and indoor light led to accelerated growth of healthy cells. Exposure to fluorescent lamps was followed by long term storage in darkness, to monitor the bacterial repair in the dark. The response was correlated with the pre-exposure dose of applied solar irradiation, and to a lesser extent with the fluorescent light dose. Bacteria which had undergone extensive exposure showed no response under fluorescent light or during storage in the dark. Finally, the statistical treatment of the data allowed us to suggest a linear model, which is non-selective in terms of the fluorescent light applied. The estimation of the final bacterial population was predicted well (R-sq similar to 75%) and the photoreactivation risk was found to be more important for cultivable cells.

The generation of high-coloured wastewater is one of the main environmental problems of the textile industry. Reactive dyes are widely used in the dyeing of cellulosic fibres. However, they have low exhaustion degree (70–90%). The degradation of residual dyes by aerobic biological treatment is very poor, being necessary the application of specific treatments. In this work, three different methods for the removal of reactive dyes were compared: electrochemical treatment, coagulation with Moringa oleifera waste and enzymatic treatment with laccase. Two azo bifunctional dyes with different reactive groups were selected: C.I. Reactive Black 5 (vinyl sulphone) and C.I. Reactive Red 231 (chlorotriazine). The influence of pH (5 and 9) and dye hydrolysis on the decolourisation yield was studied. The electrochemical treatment was the most efficient, with 95–100% colour removal yield. The coagulation with M. oleifera waste also achieved high colour removal efficiency (91–94%). Both methods showed an independent behaviour with respect to pH or dye hydrolysis. The enzymatic treatment should be performed at pH 5. This method was suitable to remove the chlorotriazine dye (92–93% efficiency), whereas the vinyl sulphone one showed a marked dependence on dye hydrolysis: moderately efficient for the hydrolysed dye and highly efficient without hydrolysis. The activity of laccase was not modified by the usual salinity of the reactive dyeing effluent (20 g/L NaCl). Nevertheless, the effluent salinity enhanced the electrochemical and M. oleifera treatment yield.

In this work, solar disinfection of wastewater was studied, focusing on the effect of selected environmental variables, namely light intensity, continuous/intermittent light delivery, and post-irradiation storage as well as dilution in lake water. These variables were studied for their effect on the disinfection efficiency and on post-irradiation survival/regrowth in undiluted wastewater and in wastewater diluted in lake water at different dilution rates. The bacterial inactivation curves were studied, and distinct kinetic phases were identified and interpreted. The dose primarily influenced the demonstration of phases and total inactivation times, independently of the irradiance. Intermittent illumination unevenly prolonged the required exposure time and highlighted the need for extended illumination times when unstable weather conditions are expected. Post-irradiation survival/regrowth in undiluted wastewater showed three distinct kinetic profiles, with transitions among them largely determined by the applied light dose. Lower doses resulted in similar inactivation profiles to the higher ones, when irradiation was followed by prolonged storage at high dilution rates in lake water. The studied factors show significant design and operation implications for solar wastewater applications based on local environmental conditions and water receptor restrictions.

This study is on the reuse of the residue generated by a Moringa oleifera oil extraction plant. The residual oil cake produced during the process of oil extraction retains the positively charged protein of the M. oleifera seed, which is the active component in the process of attracting and capturing suspended particles in waters. Such coagulant flocculant properties give rise to the elimination of turbidity in the process of water purification. In the cases studied, it has been demonstrated that the same amount (100 mg/L) of Aluminum sulfate coagulant and M. oleifera coagulant is required to reduce water turbidity to levels within the International guidelines (

In this work, the feasibility of polyvinylidene difluoride ultrafiltration membranes to treat textile wastewater was studied. The C.I. Disperse Orange 30 and C.I. Disperse Rubine 73 were selected as pollutant for the membrane filtration study. The results showed about 90 and 96% of COD decrease and dye removal, respectively. In addition, very low fouling was observed which demonstrated the feasibility of applying this type of membranes to treat textile wastewater. Finally, after the membrane treatment, 100% of the obtained permeate was reused. Fabrics dyed with the reused water were evaluated with respect to references carried out with softened tap water. No significant colour differences were observed between reference fabrics and the fabrics dyed with the permeate.

Lemon essential oil is one of the most widely used natural flavours in the food and beverage industries. Knowledge of the enantiomeric ratio in flavours has gained relevance because they may indicate differences in their organoleptic characteristics or their authenticity. The study was carried out during the growth of the lemon fruit to evaluate the possible variations of the enantiomeric ratio of four characteristic terpenes: a-pinene, ß-pinene, linalool and limonene. Two extraction methods were applied to extract the terpenes: simultaneous distillation–extraction at reduced pressure (V-SDE) and solid-phase microextraction; the results were equivalent whatever the method applied. In both cases, the target compounds were obtained from the lemon peel. Enantiomeric profiles were obtained by enantioselective multi-dimensional gas chromatography–mass spectrometry (enantio-MDGC-MS). Consistent enantiomeric ratios of a-pinene, ß-pinene and limonene were observed; however, the enantiomeric ratio of linalool varied significantly according to the growth stage of the lemons in a spontaneous and natural way