Environmental reporting in Italian thermal power plants: insights from a comprehensive analysis of EMAS environmental statements.

The global energy sector heavily relies on fossil fuels, significantly contributing to climate change. The ambitious European emissions' reduction targets require sustainable processes and alternatives. This study presents a comprehensive analysis of 73 Italian thermal power plants registered to the European Eco-Management and Audit Scheme (EMAS) aimed at assessing EMAS effectiveness in addressing and quantifying the environmental impacts of this relevant industrial sector. The analysis was based on EMAS environmental statements, publicly disclosing verified and certified data, with the secondary objective of evaluating if EMAS could be an efficient tool to improve the plants' environmental performances. An inventory of technical and environmental aspects, adopted indicators, and allocated budgets was based on 2023 data. A strong correlation was found between the significance of the environmental aspects and the number of adopted indicators. Gaps were observed in describing aspects like "biodiversity" and "local issues". Improvement objectives and budget allocation showed discrepancies and lacked correlation with the significance of the related environmental aspects. "Energy production" accounted for 68% of the total allocated budget; "environmental risks", "emissions to air", "electricity consumption", and "local issues" were also key focus areas. Insufficient information on emission control technologies and progress tracking of improvement objectives was detected. This study highlights the need for thermal power installations to improve the selection of appropriate indicators and to better relate allocated budget to improvement objectives when implementing EMAS. Such measures would facilitate the quantification of the effective environmental impacts of the energy production sector, supporting future research on this topic, allowing stakeholders a better comparison among plants, and driving industry-wide improvements.

Review of lithium-ion batteries' supply-chain in Europe: Material flow analysis and environmental assessment.

European legislation stated that electric vehicles' sale must increase to 35% of circulating vehicles by 2030, and concern is associated to the batteries' supply chain. This review aims at analysing the impacts (about material flows and CO2 eq emissions) of Lithium-Ion Batteries' (LIBs) recycling at full-scale in Europe in 2030 on the European LIBs' supply-chain. Literature review provided the recycling technologies' (e.g., pyro- and hydrometallurgy) efficiencies, and an inventory of existing LIBs' production and recycling plants in Europe. European production plants exhibit production capacity adequate for the expected 2030 needs. The key critical issues associated to recycling regard pre-treatments and the high costs and environmental impacts of metallurgical processes. Then, according to different LIBs' composition and market shares in 2020, and assuming a 10-year battery lifetime, the Material Flow Analysis (MFA) of the metals embodied in End of Life (EoL) LIBs forecasted in Europe in 2030 was modelled, and the related CO2 eq emissions calculated. In 2030 the European LIBs' recycling structure is expected to receive 664 t of Al, 530 t of Co, 1308 t of Cu, 219 t of Fe, 175 t of Li, 287 t of Mn and 486 t of Ni. Of these, 99% Al, 86% Co, 96% Cu, 88% Mn and 98% Ni will be potentially recovered by pyrometallurgy, and 71% Al, 92% Co, 92% Fe, 96% Li, 88 % Mn and 90% Ni by hydrometallurgy. However, even if the recycling efficiencies of the technologies applied at full-scale are high, the treatment capacity of European recycling plants could supply as recycled metals only 2%-wt of the materials required for European LIBs' production in 2030 (specifically 278 t of Al, 468 t of Co, 531 t of Cu, 114 t of Fe, 95 t of Li, 250 t of Mn and 428 t of Ni). Nevertheless, including recycled metals in the production of new LIBs could cut up 28% of CO2 eq emissions, compared to the use of virgin raw materials, and support the European batteries' value chain.

Closed-loop recycling of lithium iron phosphate cathodic powders via citric acid leaching.

Lithium recovery from Lithium-ion batteries requires hydrometallurgy but up-to-date technologies aren't economically viable for Lithium-Iron-Phosphate (LFP) batteries. Selective leaching (specifically targeting Lithium and based on mild organic acids and low temperatures) is attracting attention because of decreased environmental impacts compared to conventional hydrometallurgy. This study analysed the technical and economic performances of selective leaching with 6%vv. H2O2 and citric acid (0.25-1 M, 25 °C, 1 h, 70 g/l) compared with conventional leaching with an inorganic acid (H2SO4 1 M, 40 °C, 2 h, 50 g/l) and an organic acid (citric acid 1 M, 25 °C, 1 h, 70 g/l) to recycle end of life LFP cathodes. After conventional leaching, chemical precipitation allowed to recover in multiple steps Li, Fe and P salts, while selective leaching allowed to recover Fe and P, in the leaching residues and required chemical precipitation only for lithium recovery. Conventional leaching with 1 M acids achieved leaching efficiencies equal to 95 ± 2% for Li, 98 ± 8% for Fe, 96 ± 3% for P with sulfuric acid and 83 ± 0.8% for Li, 8 ± 1% for Fe, 12 ± 5% for P with citric acid. Decreasing citric acid's concentration from 1 to 0.25 M didn't substantially change leaching efficiency. Selective leaching with citric acid has higher recovery efficiency (82 ± 6% for Fe, 74 ± 8% for P, 29 ± 5% for Li) than conventional leaching with sulfuric acid (69 ± 15% for Fe, 70 ± 18% for P, and 21 ± 2% for Li). Also, impurities' amounts were lower with citric acid (335 ± 19 335 ± 19 of S mg/kg of S) than with sulfuric acid (8104 ± 2403 mg/kg of S). In overall, the operative costs associated to 0.25 M citric acid route (3.17€/kg) were lower compared to 1 M sulfuric acid (3.52€/kg). In conclusion, citric acid could be a viable option to lower LFP batteries' recycling costs, and it should be further explored prioritizing Lithium recovery and purity of recovered materials.

Medial or Lateral, That Is the Question: A Retrospective Study to Compare Two Injection Techniques in the Treatment of Knee Osteoarthritis Pain with Hyaluronic Acid.

Background: Mild-to-moderate knee osteoarthritis (KOA) can be successfully treated using intra-articular hyaluronic acid (IA-HA). The medial infrapatellar (MIP) approach and lateral infrapatellar (LIP) approach are two of the most used techniques for performing IA-HA, but it is still not clear which one is preferable. Objectives: The study aims to find the best knee injection technique between MIP and LIP approaches. Methods: In total, 161 patients were enrolled, divided into two groups (MIP or LIP). Each technique was performed once a week for three weeks. Patients were evaluated using the Numeric Rating Scale (NRS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Roles and Maudsley Score (RMS) at T0 (before the first injection), T1 (one week after the third injection) and T2 (six months after). Results: NRS, KOOS and RMS showed a statistically significant improvement in both groups at all the detection times, without significant differences. No differences were detected between the groups in terms of systemic effect effusions, while the MIP group presented a mildly higher number of bruises in comparison with the LIP group (p = 0.034). Conclusions: Both the IA-HA techniques are equally effective in measured outcomes. The MIP approach seems to produce some local and transient side effects. So, the choice of the LIP or MIP approach depends on the operator's skill and experience.

Assessing the environmental performances of waste-to-energy plants: The case-study of the EMAS-registered waste incinerators in Italy.

This study evaluated the environmental performances of 15 Italian waste incineration (WI) plants registered to EMAS. From the EMAS Environmental Statements, the validated data related to 5 environmental aspects (emissions to air, energy consumption/production, waste production and reagent consumption) and 24 key indicators were analyzed to describe and assess the environmental performances of the plants in 2017-2019 in relation to the best available techniques associated emission levels (BAT-AELs) and other sectorial reference values. All air pollutants' average concentrations resulted significantly below the upper BAT-AELs, the majority under the lower BAT-AELs, with an overall slightly decreasing trend (-4.6%). The specific productions of bottom and other ashes were steady over time and just above the lower characteristic values. The specific energy consumption was higher than the average European performance and stable over time, while the specific reagent consumption was harder to evaluate, with results varying for the different reagents. An evaluation of the influence of the WI plants' characteristics on the environmental performances was also performed considering 13 different parameters (e.g., flue gas cleaning technologies, waste treatment capacity, etc.). A correlation analysis highlighted the positive influence of the pre-dedusting stages on overall emissions, specific reagents consumption and specific waste production, and of the plant size on the specific energy production. This study demonstrated that EMAS can provide a tool to evaluate the environmental performances of WI plants and compare different installations using certified data. It also highlighted the excellent performances of the Italian WI plants registered to EMAS compared to the sectorial references.

Analysis of the influence of mobile phones' material composition on the economic profitability of their manual dismantling.

This work presents a systematic characterisation of 100 waste mobile phones (73 feature phones and 23 smartphones) produced between 1989 and 2016. All items were inventoried and the evolvement of the relative abundances of their macro-components (mechanic and electro-mechanic parts, electronics and others) and materials was investigated. The average lifetime was 15.1 years for feature phones and 6.4 years for smartphones. The main component was plastic, on average 46%-wt. in feature phones and 37%-wt. in smartphones; over the years electronics' and plastic's amounts decreased (respectively 80% and 70%), while metal components' amount increased (12%). A cost-benefit analysis explored the profitability of the management of waste mobile phones through manual dismantling followed by the sale of the separated components and materials. The average cost of manual dismantling was estimated as 6.93 € per item according to EU average labour costs and 1.50 € per item based on minimum EU labour costs. According to the performed economic analysis, the actual market prices for the potentially recoverable materials and components of waste mobile phones were not able (particularly mixed plastics) to counterbalance the costs of manual dismantling according to the European standard labour costs.

Recovery of Waste Polyurethane from E-Waste. Part II. Investigation of the Adsorption Potential for Wastewater Treatment.

This study explored the performances of waste polyurethane foam (PUF) derived from the shredding of end-of-life refrigerators as an adsorbent for wastewater treatment. The waste PUF underwent a basic pre-treatment (e.g., sieving and washing) prior the adsorption tests. Three target pollutants were considered: methylene blue, phenol, and mercury. Adsorption batch tests were performed putting in contact waste PUF with aqueous solutions of the three pollutants at a solid/liquid ratio equal to 25 g/L. A commercial activated carbon (AC) was considered for comparison. The contact time necessary to reach the adsorption equilibrium was in the range of 60-140 min for waste PUF, while AC needed about 30 min. The results of the adsorption tests showed a better fit of the Freundlich isotherm model (R2 = 0.93 for all pollutants) compared to the Langmuir model. The adsorption capacity of waste PUF was limited for methylene blue and mercury (Kf = 0.02), and much lower for phenol (Kf = 0.001). The removal efficiency achieved by waste PUF was lower (phenol 12% and methylene blue and mercury 37-38%) compared to AC (64-99%). The preliminary results obtained in this study can support the application of additional pre-treatments aimed to overcome the adsorption limits of the waste PUF, and it could be applied for "rough-cut" wastewater treatment.

Recovery of Waste Polyurethane from E-Waste-Part I: Investigation of the Oil Sorption Potential.

The shredding of end-of-life refrigerators produces every year in Italy 15,000 tons of waste polyurethane foam (PUF), usually destined for energy recovery. This work presents the results of the investigation of the oil sorption potential of waste PUF according to ASTM F726-17 standard. Three oils (diesel fuel and two commercial motor oils) having different densities (respectively, 0.83, 0.87, and 0.88 kg/dm3) and viscosities (respectively, 3, 95, and 140 mm2/s at 40 °C) were considered. The waste PUF was sampled in an Italian e-waste treatment plant, and its characterization showed 16.5 wt% particles below 0.71 mm and 13 wt% impurities (paper, plastic, aluminum foil), mostly having dimensions (d) above 5 mm. Sieving at 0.071 mm was applied to the waste PUF to obtain a "coarse" (d > 0.71 mm) and a "fine" fraction (d < 0.71 mm). Second sieving at 5 mm allowed an "intermediate" fraction to be obtained, with dimensions between 0.71 and 5 mm. The oil sorption tests involved the three fractions of waste PUF, and their performances were compared with two commercial oil sorbents (sepiolite and OKO-PUR). The results of the tests showed that the "fine" PUF was able to retain 7.1-10.3 g oil/g, the "intermediate" PUF, 4.2-7.4 g oil/g, and the "coarse" PUF, 4.5-7.0 g oil/g, while sepiolite and OKO-PUR performed worse (respectively, 1.3-1.6 and 3.3-5.3 g oil/g). In conclusion, compared with the actual management of waste PUF (100 wt% sent to energy recovery), the amount destined directly to energy recovery could be limited to 13 wt% (i.e., the impurities). The remaining 87 wt% could be diverted to reuse for oil sorption, and afterward directed to energy recovery, considered as a secondary option.

Investigation of the anaerobic digestion of cosmetic industrial wastes: Feasibility and perspectives.

This study assessed the anaerobic digestion (AD) of wastes deriving from cosmetics production: sludge from onsite wastewater treatment plant (sWWTP), residues of shampoo/conditioner (RSC) and sludge from mascara production (MS), considered as single substrates and as mixture according to the produced amounts (54 %-wt sWWTP, 31 %-wt RSC, 13 %-wt MS, plus 2 %-wt food waste from the canteen, FW). Total COD (CODT) was 624-1436 g O2/kg VS, while soluble COD was 5-23 %-wt of CODT. AD tests at 35 °C achieved the following biogas yields: 0.10 Nm3/kgvs (70 %-v/v methane) for sWWTP; 0.07 Nm3/kgvs (62 %-v/v methane) for RSC; 0.04 Nm3/kgvs (67 %-v/v methane) for MS. The mixed substrates underwent physico-chemical pre-treatments (thermo-alkaline, TA: 120 min at 50 °C; thermo-alkaline-sonication, TAS: 15 min at 40 kHz and 80 °C, both based on the addition of 0.08 g NaOH per each g of total solid in the substrate), reaching 64-66% disintegration rate, and AD tests (5 %-wt dry substance) at 35 and 52 °C. Biogas yields were (for TA and TAS respectively): 0.22 and 0.20 Nm3/kgVS (62-70% methane); 0.21 and 0.19 Nm3/kgVS (66-66% methane) at 52 °C. At both temperatures, methane yields considerably improved (+71-100%), compared to mixed untreated substrates, and 5-8 %-wt total solids reductions were observed. A technical-economic scale-up assessment completed the research. The energy analysis highlighted the crucial role of TA pre-treatment in achieving the process energetic sustainability. The economic analysis showed that the AD of the considered cosmetic waste could be sustainable anyway, thanks to the savings related to the disposal of the digestate compared to current waste management costs.

Evaluation of the influence of filter medium composition on treatment performances in an open-air green wall fed with greywater.

According to the European Research and Innovation Policy Agenda, nature-based solutions (NBSs) are key technologies to improve the sustainability of urban areas. Among NBSs, green walls have been recently studied for several applications, among the others the treatment of lowly polluted wastewater flows as greywater (GW, e.g. domestic wastewater excluding toilet flushes). This work is aimed at the evaluation of the influence of four additives (compost, biochar, granular activated carbon, polyacrylate) mixed with a base filter medium made of coconut fibre and perlite, on the performances of a green wall fed in batch mode with synthetic GW. The green wall was operated with a high hydraulic loading rate of GW (740.8 L/m2/day) in open-air winter conditions (3.5-15 °C measured for GW) between January and April. The performances of the green wall have been assessed though the monitoring every 1-2 weeks of physicochemical and biological parameters (pH, electric conductivity, total suspended solids, dissolved oxygen, BOD5 and COD, nitrogen and phosporus compounds, chlorides and sulphates, anionic surfactants and E. coli). Removal performances were excellent for BOD5 (>95%) and E.coli (>98%) for all additives; compared to the base medium, biochar was the best performing additive over the highest number of parameters, achieving removals equal to 51% for COD, 47% for TKN and nitric nitrogen and 71% for anionic surfactants. Compost also achieved high removal performances, but the frequent clogging events occurred during the monitoring period do not make its use recommendable. Granular activated carbon and the combination of biochar and polyacrylate performed better than the base medium, but only about the removal of nitric nitrogen. These results demonstrated that, in the considered experimental boundaries, biochar could improve the overall treatment performances of a green wall fed by GW and operated in challenging conditions.

Semi-continuous anaerobic digestion of mixed wastewater sludge with biochar addition.

This work analysed the effects of Biochar (BC) addition to the Anaerobic digestion (AD) of wastewater Mixed sludge (MS) in semi-continuous mode. A 3 L digester was operated at 37 °C for 100 days, feeding MS collected every three weeks in the same wastewater treatment plant, and 10 g L-1 of BC. The average performance of MS digestion (biogas 188 NmL d-1, 68% methane) improved in presence of BC (biogas 244 NmL d-1, 69% methane). According to the results of the multiple linear regression analysis performed on the experimental data, the 79% variation of the soluble COD in the MS was the driving factor for the 38% increase of biogas and methane yields. In conclusion, in the considered experimental conditions, the variability of the substrate's composition was the key factor driving the performances of the AD of MS, independently of the addition of BC.

A Novel Dry Treatment for Municipal Solid Waste Incineration Bottom Ash for the Reduction of Salts and Potential Toxic Elements.

The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilot-scale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4. The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%), chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization.

A review of nature-based solutions for greywater treatment: Applications, hydraulic design, and environmental benefits.

Recognizing greywater as a relevant secondary source of water and nutrients represents an important chance for the sustainable management of water resource. In the last two decades, many studies analysed the environmental, economic, and energetic benefits of the reuse of greywater treated by nature-based solutions (NBS). This work reviews existing case studies of traditional constructed wetlands and new integrated technologies (e.g., green roofs and green walls) for greywater treatment and reuse, with a specific focus on their treatment performance as a function of hydraulic operating parameters. The aim of this work is to understand if the application of NBS can represent a valid alternative to conventional treatment technologies, providing quantitative indications for their design. Specifically, indications concerning threshold values of hydraulic design parameters to guarantee high removal performance are suggested. Finally, the existing literature on life cycle analysis of NBS for greywater treatment has been examined, confirming the provided environmental benefits.

Classification of plastic waste originated from waste electric and electronic equipment based on the concentration of antimony.

The aim of this research is a preliminary assessment of antimony concentration in plastic fractions deriving from different e-waste. We considered microwave ovens, desktop computers, laptops, mobile phones, a TV case, a PC monitor and LED lamps (63 items in total). The plastic fraction ranged from 8%-wt in computers and microwave ovens, up to 40%-wt in cell phones and 59%-wt in LED lamps. Specific polymers were identified through Near Infrared spectroscopy. The samples followed three parallel procedures: acid digestion with aqua regia; conversion into ashes at 600 °C then acid digestion with aqua regia; leaching according to UNI10802 reference procedure. Plastic components with significant amounts of antimony were the ones derived from desktop computers (25-1900 mg/kg) and from microwave ovens (830 mg/kg), yet their relative amount compared to the total weight of the item was limited. Items with larger plastic fractions showed lower concentrations of antimony (1-6 mg/kg in mobile phones cases and 160-640 mg/kg in plastic components of LED lamps). Leaching tests revealed that the analyzed plastic fractions could be mostly admitted in non-hazardous waste landfills. The analysis of ashed samples highlighted the need to further improve the acidic extraction procedure.

Techno-economic assessment of non-sterile batch and continuous production of lactic acid from food waste.

Non-sterile lactic acid (LA) fermentation of highly viscous food waste was demonstrated in batch and continuous flow fermentations. With Streptococcus sp., an indigenous consortium, and/or applied glucoamylase, food waste was fermented without addition of external carbon or nitrogen sources. Experimental results were used for economic and energy evaluations under consideration of different catchment area sizes from 50,000 to 1,000,000 inhabitants. During batch mode, addition of glucoamylase resulted in a titer (after 24 h), yield, and productivity of 50 g L-1, 63%, and 2.93 g L-1h-1, respectively. While titer and yield were enhanced, productivity was lower during continuous operation and 69 g L-1, 86%, and 1.27 g L-1h-1 were obtained at a dilution rate of 0.44 d-1 when glucoamylase was added. Both batch and continuous flow fermentations were found economically profitable with food waste from 200,000 or more inhabitants.

Improving waste electric and electronic equipment management at full-scale by using material flow analysis and life cycle assessment.

This work has as main objective the analysis of waste from electric and electronic equipment (WEEE or e-waste) management through material flow analysis and life cycle assessment of a full-scale Italian facility that is significant about the e-waste flows treated (9900 t/y) and representative of a developed EU country about the industrial process outline, based on manual dismantling phases and physic-mechanical automatic processes. Three WEEE categories (i.e. R1-Cooling equipment, R2-Large household appliances and R3- TVs and screens) have been chosen with the reason that they are the most abundant in EU. The methodology was based on two end-of-life scenarios: S0-partial recycling of valuable fractions and landfilling of the rest, which is conventional e-waste processing in Italian facilities; S1-complete recycling of valuable fractions, limited incineration and landfilling of the rest, which describes what happens in the considered case study. Mass balance of the three treatment lines showed recycling rate (RR) values equal to: for R1 40% for S0 and 80% for S1; for R2 65% for S0 and 99% for S1; for R3 86% for S0 and 91% for S1, with significant fractions incinerated or landfilled only for R1 treatment line. Life cycle assessment considered transport (post-consumer collection), treatment, recycling, incineration and disposal. As main results, eco-toxicity aquatic potentials referring to marine and fresh water were the most relevant impact categories. In conclusion, recycling (mostly of metals) played a crucial role for environmental benefits, and transport and polyurethane plus rubber incineration for the environmental impacts.

Assessment of plastic waste materials degradation through near infrared spectroscopy.

Plastic waste is a relevant challenge for waste management sector and further technological means have to be urgently researched. The evaluation of plastic waste quality through non-destructive, cost-effective and mature technologies could be without any doubt a key issue. This study is aimed at the assessment of Near Infrared (NIR) spectroscopy for the generation of global degradation-prediction models able to forecast plastic ageing. The degradation of Polyethylene terephthalate (PET), Acrylonitrile Butadiene Styrene (ABS), Polypropylene (PP) and Polyethylene (PE) was achieved by thermal ageing (at 85 °C, 105 °C and 120 °C and durations ranging from 4 to 504 h), to simulate environmental outdoor conditions. Experimental data obtained for each plastic material were elaborated through partial least square (PLS) regression to obtain empirical models. For all inspected plastic materials, a good correspondence between the variation in absorbance units and the change in chemical bonds vibrations was observed. The PLS models were afterwards calibrated (taking into account the different ageing conditions; first separately then including the ageing factors combined). A high accuracy (R2 equal to 0.85-1.00) was observed in predicting ageing for PET and ABS, while the correspondence showed a 30% decrease for PE and PP. This study proves that NIR spectroscopy can be recommended as an effective tool to investigate plastics degradation, with some limitations for specific polymers that need further investigations.

Assessment of the waste electrical and electronic equipment management systems profile and sustainability in developed and developing European Union countries.

The assessment of waste management systems for electrical and electronic equipment (WEEE) from developed economies (Germany, Sweden and Italy) and developing countries (Romania and Bulgaria), is discussed covering the period 2007-2014. The WEEE management systems profiles are depicted by indicators correlated to WEEE life cycle stages: collection, transportation and treatment. The sustainability of national WEEE management systems in terms of greenhouse gas emissions is presented, together with the greenhouse gas efficiency indicator that underlines the efficiency of WEEE treatment options. In the countries comparisons, the key elements are: robust versus fragile economies, the overall waste management performance and the existence/development of suitable management practices on WEEE. Over the life cycle perspective, developed economies (Germany, Sweden and Italy) manage one order of magnitude higher quantities of WEEE compared to developing countries (Romania and Bulgaria). Although prevention and reduction measures are encouraged, all WEEE quantities were larger in 2013, than in 2007. In 2007-2014, developed economies exceed the annual European collection target of 4 kg WEEE/capita, while collection is still difficult in developing countries. If collection rates are estimated in relationship with products placed on market, than similar values are registered in Sweden and Bulgaria, followed by Germany and Italy and lastly Romania. WEEE transportation shows different patterns among countries, with Italy as the greatest exporter (in 2014), while Sweden treats the WEEE nationally. WEEE reuse is a common practice in Germany, Sweden (from 2009) and Bulgaria (from 2011). By 2014, recycling was the most preferred WEEE treatment option, with the same kind of rates performance, over 80%, irrespective of the country, with efforts in each of the countries in developing special collection points, recycling facilities and support instruments. The national total and the recycling carbon footprints of WEEE are lower in 2013 than in 2007 for each country, the order in reducing the environmental impacts being: Germany, Italy, Sweden, Bulgaria and Romania. The negative values indicate savings in greenhouse gas emissions. In 2013, the GHG efficiency shows no differences of the WEEE management in the developed and developing countries.

Investigation of food waste valorization through sequential lactic acid fermentative production and anaerobic digestion of fermentation residues.

This work concerns the investigation of the sequential production of lactic acid (LA) and biogas from food waste (FW). LA was produced from FW using a Streptococcus sp. strain via simultaneous saccharification and fermentation (SSF) and separate enzymatic hydrolysis and fermentation (SHF). Via SHF a yield of 0.33gLA/gFW (productivity 3.38gLA/L·h) and via SSF 0.29gLA/gFW (productivity 2.08gLA/L·h) was obtained. Fermentation residues and FW underwent anaerobic digestion (3wt% TS). Biogas yields were 0.71, 0.74 and 0.90Nm3/kgVS for FW and residues from SSF and SHF respectively. The innovation of the approach is considering the conversion of FW into two different products through a biorefinery concept, therefore making economically feasible LA production and valorising its fermentative residues. Finally, a mass balance of three different outlines with the aim to assess the amount of LA and biogas that may be generated within different scenarios is presented.

Scale effect of anaerobic digestion tests in fed-batch and semi-continuous mode for the technical and economic feasibility of a full scale digester.

Methane production capacity in mesophilic conditions of waste from two food industry plants was assessed in a semi-pilot (6L, fed-batch) and pilot (300 L, semi-continuous) scale. This was carried out in order to evaluate the convenience of producing heat and electricity in a full scale anaerobic digester. The pilot test was performed in order to obtain more reliable results for the design of the digester. Methane yield, returned from the pilot scale test, was approximately 80% of that from the smaller scale test. This outcome was in line with those from other studies performed in different scales and modes and indicates the success of the pilot scale test. The net electricity produced from the digester accounted for 30-50% of the food industry plants' consumption. The available thermal energy could cover from 10% to 100% of the plant requirements, depending on the energy demand of the processes performed.