Elizabeth C. N. F. A. Duarte (original) (raw)

Papers by Elizabeth C. N. F. A. Duarte

Frontiers in Sustainable Food Systems

In the past years, there has been steady growth in work relating to improve resource efficiency t... more In the past years, there has been steady growth in work relating to improve resource efficiency through waste minimization and bioenergy recovery to mitigate climate change. Agro-food industries produce large amounts of bio-waste, challenging innovative energetic valorization strategies in the framework of circular economy principles. Anaerobic digestion (AD) technology is an interesting route to stabilize organic matter and produce biogas as a renewable energy source. This study involves continuous co-digestion of pig slurry (PS), cereal and exhausted coffee wastes (CECW) performed in a continuously stirred tank reactor, with a hydraulic retention time (HRT) of 16 days under at mesophilic conditions (36.9 ± 0.3°C). The experimental trials, were designed to include different cereal and exhausted coffee liquor (CECL) shares in the feeding mixture, corresponding to different PS to CECL ratios (PS:CECL), respectively: 100:0 (T0), 90:10 (T1), 80:20 (T2), and 70:30 (T3), in terms of perc...

I Congresso Luso-Brasileiro de Horticultura. Sessão Horticultura Biológica (Orgânica)Avaliou-se o... more I Congresso Luso-Brasileiro de Horticultura. Sessão Horticultura Biológica (Orgânica)Avaliou-se o efeito de diferentes tipos de cobertura do solo sobre as características dos frutos do pimentão (Capsicum annuum L. cv. Yolo Wonder) e incidência de plantas infestantes num ensaio de campo nas instalações do Departamento de Ciências Agrárias (UNITAU), em Taubaté-SP, a 23º02’34”S e 45º31’02”W, com altitude média de 577 m, em um Latossolo Vermelho Amarelo distrófico de textura média. O delineamento experimental utilizado foi de blocos casualizados com cinco repetições e quatro tratamentos: 1-cobertura de casca de arroz (CCA), 2-filme de polietileno preto (PE), 3-filme de bioplástico preto (ABF) e 4-solo sem cobertura(SC). Os tratamentos foram distribuídos em canteiros, com 1,2 m de largura, 0,3 m de altura e 10 m de comprimento. A irrigação por gotejamento foi colocada sobre a superfície dos canteiros, com (gotejadores distanciados 0,4 m, caudal de 1,67 L.h-1, pressão de serviço de 1,6 kP...

I Congresso Luso-Brasileiro de HorticulturaAs exigências do mercado e o enorme desajuste entre o ... more I Congresso Luso-Brasileiro de HorticulturaAs exigências do mercado e o enorme desajuste entre o curto período de tempo durante o qual as culturas necessitam do filme de cobertura e a longevidade do filme tradicional de polietileno, abriram a oportunidade para em 2010 se desenvolver o projeto Europeu AGROBIOFILM. Este projeto veio quebrar barreiras e trazer de volta ao debate público a aplicação dos filmes de cobertura biodegradáveis em Portugal, Espanha e França. Para além do desempenho agronómico, fundamental para a sua competitividade, foram determinadas características como a permeabilidade ao vapor de água e a biodegradação no solo. Desde o final do projeto e da validação da sua utilização, o Agrobiofilm® passou a ser aplicado comercialmente e já foi testado e comprovado o seu desempenho para culturas tão diversas como: morango, pimento, alface, vinha, entre outros. O projeto teve uma grande repercussão, despertando interesses no Brasil, onde deu origem ao projeto Agrisus - Ava...

Foods, 2021

Goat and second cheese whey from sheep’s milk are by-products of the manufacture of goat cheeses ... more Goat and second cheese whey from sheep’s milk are by-products of the manufacture of goat cheeses and whey cheeses from sheep. Due to their composition which, apart from water—about 92%—includes lactose, proteins, fat, and minerals, and the elevated volumes generated, these by-products constitute one of the main problems facing to cheese producers. Aiming to add value to those by-products, this study evaluates the efficiency of ultrafiltration/diafiltration (UF/DF) for the recovery of protein fraction, the most valuable component. For a daily production of 3500 and using the experimental results obtained in the UF/DF tests, a membrane installation was designed for valorization of protein fraction, which currently have no commercial value. A Cost–Benefit Analysis (CBA) and Sensitivity Analysis (SA) were performed to evaluate the profitability of installing that membrane unit to produce three new innovative products from the liquid whey protein concentrates (LWPC), namely food gels, pr...

Membranes, 2021

Goat cheese whey is a co-product that comes from goat cheese manufacture. Due to its high organic... more Goat cheese whey is a co-product that comes from goat cheese manufacture. Due to its high organic load, adequate treatment is necessary before its disposal. Additionally, the recent growing interest in caprine products, attributed to their specific nutritional and nutraceutical characteristics, such as the lower allergenicity of their proteins and higher content of oligosaccharides, compared with bovine products, made the recovery of goat cheese whey a challenge. In this study, an integrated process for the recovery of sweet goat whey components was carried out. It includes filtration, centrifugation and pasteurization, followed by sequential membrane processes, ultrafiltration/dilution, nanofiltration of ultrafiltration permeates in dilution mode and the concentration/dilution of nanofiltration retentates. Ultrafiltration was performed with membranes of 10 and 1 kDa. Membranes of 10 kDa have higher permeate fluxes and, in a single stage of dilution, allowed for better protein reten...

International Journal of Environmental Research and Public Health, 2020

The lack of access to safe drinking water causes important health problems, mainly in developing ... more The lack of access to safe drinking water causes important health problems, mainly in developing countries. In the West African country Guinea-Bissau, waterborne diseases are recognised by WHO as major infectious diseases. This study analysed the microbiological and physicochemical parameters of drinking water in the capital Bissau and its surroundings. Twenty-two sites belonging to different water sources (piped water, tubewells and shallow wells) were surveyed twice a day for three weeks, in both dry and wet seasons. Most of the microbiological parameters were out of the acceptable ranges in all types of water and both seasons and tended to worsen in the wet season. Moreover, in Bissau, the levels of faecal contamination in piped water increased from the holes to the consumer (tap/fountain). Several physicochemical variables showed values out of the internationally accepted ranges. Both well sources showed low-pH water (4.87–5.59), with high nitrite and iron levels in the wet seas...

SN Applied Sciences, 2020

Plant extracts have been used as alternatives to the conventional chemical water treatment. Morin... more Plant extracts have been used as alternatives to the conventional chemical water treatment. Moringa oleifera Lam. is one of the plants used for this purpose due to its antimicrobial and coagulant properties. However, there is no systematization of Moringa's application methodology. Different parts of the plant, extraction methods and concentrations can be applied to remove several pathogens present in contaminated drinking water. In the present work, reported Moringa applications with antimicrobial effect were systematically reviewed, in order to identify effective methodology(ies) for water treatment. Forty-nine articles were screened for: (1) part of the plant used, (2) extraction method, (3) extract concentration, (4) targeted pathogens, and (5) inhibition zone obtained. Nine articles complied with these criteria and were carefully analyzed; eight of them reported on leaf extracts and only one on seed extracts. Two approaches were used: analysis by pathogen and overall analysis. A total of eight different extraction methods were reported. Extract concentrations used ranged from 0.02 to 800 mg mL −1 and were tested on twenty pathogens. Our analysis revealed that none of such methods is effective against all the tested pathogens. However, leaf extracts obtained with distilled water or with 95% ethanol were the most effective ones for a higher number of pathogens such as Escherichia coli and, possibly, Vibrio cholerae. Moreover, Moringa's extract concentration of 30 mg mL −1 obtained by the 95% ethanol extraction method was the most efficient. Findings suggest an effective procedure to use Moringa, reinforcing its importance as an environmentally friendly alternative for water treatment in areas lacking a water supply system.

Journal of Environmental Management, 2016

The anaerobic co-digestion process in a continuous stirred-tank reactor (CSTR) was carried out un... more The anaerobic co-digestion process in a continuous stirred-tank reactor (CSTR) was carried out under mesophilic conditions (37 ± 0.2 C). All the trials were performed at a hydraulic retention time (HRT) of 15 days and the AD reactor was daily fed with a mixture of sewage sludge (SS) and elephant grass hydrolyzate (EGH). In this study, three different trials were assessed, with different mixture proportions of SSSS and EGH: F0 (100:0,v/v), F1 (75:25, v/v) and F2 (50:50, v/v), during 90 days each trial, keeping the organic loading rate (OLR) in a range of 0.94e1.16 g VS L À1 day À1. The experimental results obtained showed that the soluble chemical oxygen demand (SCOD) removal efficiency was around 77% and 86% for trials F1 and F2, respectively. SS co-digestion with EGH enhanced methane yield, leading to an increment between 23% and 38%, in comparison with the reference scenario (F0).

Waste and Biomass Valorization, 2020

Agro-food industries produce large amounts of bio-waste, challenging innovative valorisation stra... more Agro-food industries produce large amounts of bio-waste, challenging innovative valorisation strategies in the framework of circular economy principles. Anaerobic digestion technology is an interesting route to stabilise organic matter and produce biogas as a renewable energy source. This paper aimed to study the optimal performance conditions for anaerobic co-digestion (AcoD) of pig slurry with pineapple (Ananas comosus) peel bio-waste. The anaerobic digestion (AD) trials were performed at lab scale, in a continuous stirred reactor, for 16 days' hydraulic retention time in mesophilic conditions (37 ± 1 °C). Three hydraulic retention time were performed, one for the reference scenario (T 0) and two for AcoD trials (T 1 , T 2). Feeding mixtures (20:80; v:v) of pineapple peel liquor and pig slurry, with an OLR of 1.46 ± 0.04 g TVS L −1 reactor day −1 were used during AD/AcoD trials, presenting high values for soluble chemical oxygen demand and C/N ratio. This operational conditions highlight bioenergy recovery up to 0.58 L CH 4 g TVS added −1 , in comparison with that obtained with pig slurry substrate (0.31 L CH 4 g VS added −1). The AD performance showed a total volatile solids and chemical oxygen demand removal efficiency of 23% to 47% and 26% to 48%, comparing T 0 with the average of T 1 and T 2 , respectively. The digester stability, evaluated by specific energetic loading rate, was below the limit (0.4 day −1) throughout the trials. Pig slurry co-digestion with pineapple peel liquor seems to be a promising approach for potential bioenergy recovery.

Encyclopedia of Agriculture and Food Systems, 2014

Water scarcity motivates the use/recycling of nonconventional water resources, mainly saline and ... more Water scarcity motivates the use/recycling of nonconventional water resources, mainly saline and drainage waters, treated wastewater, and desalinated water for agriculture. The characteristics of those waters point out the need to control the impacts on the environment and the soil, to manage crops in agreement with the characteristics of the used water, mainly for wastewater, and the need to avoid health consequences for workers and consumers of the produces. This article aims to review the main benefits, constraints, technologies, and strategies of recycling saline waters, wastewater, and desalinated water in irrigation.

Water Science and Technology, 2012

Olive mill wastewater (OMW) results from the production of olive oil, which is an important tradi... more Olive mill wastewater (OMW) results from the production of olive oil, which is an important traditional agro-industry in Mediterranean countries. In continuous three-phase centrifugation 1.0–1.2 m3 of OMW are produced per ton of processed olives. Discharge of OMW is of serious environmental concern due to its high content of organic matter with phytotoxic properties, namely phenolic compounds. Meanwhile, drinking water treatment sludge (DWTS) is produced in high amounts and has long been considered as a waste for landfill. The aim of this work was the assessment of reusing DWTS for OMW treatment. High performance liquid chromatography (HPLC) analysis was carried out to determine the phenolic compounds present and to evaluate if they are recalcitrant. Treatability assays were performed using a dosage of DWTS from 50 to 300 g L−1. Treatment efficiency was evaluated based on the removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD), total solids (TS), total suspended...

Chemosphere, 2008

A greenhouse pot experiment was conducted to evaluate the effect of sewage sludge (SS), of sugar ... more A greenhouse pot experiment was conducted to evaluate the effect of sewage sludge (SS), of sugar beet sludge (SBS), or of a combination of both, in the remediation of a highly acidic (pH 3.6) metal-contaminated soil, affected by mining activities. The SS was applied at 100 and 200 Mg ha À1 (dry weight basis), and the SBS at 7 Mg ha À1. All pots were sown with Italian ryegrass (Lolium multiflorum Lam.). After 60 d of growth, shoot biomass was quantified and analysed for Cu, Pb and Zn. The pseudo-total and bioavailable contents of Cu, Pb and Zn and the enzymatic activities of b-glucosidase, acid phosphatase, cellulase, protease and urease were determined in the soil mixtures. Two indirect acute bioassays with leachates from the soil (luminescent inhibition of Vibrio fischeri and Daphnia magna immobilization) were also used. The SS, in particular when in combination with SBS, corrected soil acidity, while increasing the total organic matter content and the cation exchange capacity. The application of SS led to a decrease in the level of effective bioavailable metals (extracted by 0.01 M CaCl 2 , pH 5.7, without buffer), but caused an increase in their potential bioavailability (extracted by a solution of 0.5 M NH 4 CH 3 COO, 0.5 M CH 3 COOH and 0.01 M EDTA, pH 4.7). Plant biomass increased more than 10 times in the presence of 100 Mg SS ha À1 , and more than five times with the combined use of 100 Mg SS ha À1 and SBS, but a considerable phytotoxic effect was observed for the application rate of 200 Mg SS ha À1. Copper, Pb and Zn concentrations in the shoots of L. multiflorum decreased significantly when using 100 Mg SS ha À1 or SBS. The activities of b-glucosidase, urease and protease increased with increasing SS applications rates, but cellulase had a reduced activity when using 200 Mg ha À1 SS. Both amendments were able to suppress soil toxicity to levels that did not affect D. magna, but increased the soil leachate toxicity towards V. fischeri, especially with the application of 200 Mg SS ha À1. This study showed that for this type of mine soils, and when using SS of similar composition, the maximum SS application rate should be 100 Mg ha À1 , and that liming the SS amended soil with SBS did not contribute to a further improvement in soil quality.

Bioremediation Journal, 2008

Incubation tests were used to assess the effectiveness of three different organic residues and th... more Incubation tests were used to assess the effectiveness of three different organic residues and three different liming materials, alone or in combination, in the remediation of a mine contaminated soil. The organic residues tested were sewage sludge from a municipal wastewater ...

Journal of Sustainable Development of Energy, Water and Environment Systems, 2017

Over the last decades, phytodepuration has been considered an efficient technology to treat waste... more Over the last decades, phytodepuration has been considered an efficient technology to treat wastewaters. The present study reports a bench scale depuration assay of swine wastewater using Lemna minor. The highest observed growth rate obtained in swine wastewater was 3.1 ± 0.3 gDW m −2 day −1 and the highest nitrogen and phosphorus uptake were 140 mg N m −2 day −1 and 3.47 mg P m −2 day −1 , respectively. The chemical oxygen demand removal efficiency in the swine wastewater assay was 58.9 ± 2.0%. Furthermore, the biomass valorisation by anaerobic co-digestion with swine wastewater was assessed. Results showed a clear improvement in specific methane production rate (around 40%) when compared to mono-substrate anaerobic digestion. The highest methane specific production, 131.0 ± 0.8 mL CH4 g −1 chemical oxygen demand, was obtained with a mixture containing 100 g of duckweed per liter of pre-treated swine wastewater. The water-nutrients-energy nexus approach showed to be promising for swine waste management.

A produção suinícola é uma atividade económica de grande importância, mas que tem um impacte ambi... more A produção suinícola é uma atividade económica de grande importância, mas que tem um impacte ambiental elevado, devido às emissões de gases com efeito de estufa e também à poluição associada ao chorume produzido. Como forma de minimizar esses impactes é importante o desenvolvimento de modelos de gestão assentes em novas tecnologias eficientes e de baixo custo. A co-digestão anaeróbia tem tido um papel relevante como tecnologia de bioconversão, combinando as potencialidades de dois ou mais substratos com diferentes características, no âmbito de uma bioenergia sustentável. O objetivo deste estudo é avaliar o desempenho de um sistema de tratamento e valorização de chorumes suinícolas, em co-digestão com macrófitas, como processo integrado de bioconversão. Numa primeira etapa pretende-se estudar a cinética de crescimento de Lemna minor na fração líquida do chorume, rica em macro e micronutrientes, em distintas condições operacionais, de modo a potenciar a acumulação de amido e/ou de líp...

Water Science and Technology, 2009

An air micro-bubble bioreactor (AMBB) using a free self-adapted microbial population, 15 dm 3 wor... more An air micro-bubble bioreactor (AMBB) using a free self-adapted microbial population, 15 dm 3 working volume, was used for aerobic treatment of winery wastewater. This reactor utilizes a Venturi injector in conjunction with mass transfer multiplier nozzles, which allow an efficient oxygen transfer. The reactor can operate in batch or continuous conditions. The dynamics of chemical oxygen demand (COD), biomass and total contents of polyphenolic compounds was followed throughout each trial. The wastewater COD ranged between 4.0-8.0 kg COD m 23 and the efficiency of the batch treatment was about 90.0^4.3%, after 6 days of operation. The maximum efficiency obtained was achieved after 15 days of treatment (99%). In continuous conditions, the loading rate and the treatment efficiency ranged between 0.45-1.00 kg COD m 23 d 21 and 93.3^2.0%, respectively. The AMBB hydraulic retention time was 15 days. To assess the suitability of treated water in relation to vineyard irrigation, the effluent was physico-chemical analysed and direct toxicity bioassays with effluent matrix were carried out using Lepidium sativum L. seeds. The results showed the water quality required to be reutilised minimizing water consumption. This study will contribute for the implementation of an efficient water use plan, aiming the preservation of the water resource and the reduction of the wastewater production.

Ambiente e Agua - An Interdisciplinary Journal of Applied Science, Dec 26, 2019

The study reports the performance of a sanitary effluent treatment constituted by a septic tank, ... more The study reports the performance of a sanitary effluent treatment constituted by a septic tank, anaerobic filter and constructed wetland. The study monitored nutrient's, carbonaceous material's and thermotolerant coliform's (CT) removal efficiency during 12 months. The treatment system included a septic tank, an anaerobic filter and a horizontal subsurface flow constructed wetland cultivated with Typha spp. Effluent samples were monthly collected before and after the septic tank, anaerobic filter and wetland. The removal efficiency for N-NH + 4 was 37.6%, 66.3% for total P, 37% for COD, 54% for BOD and 99.4% for CT. The anaerobic filter and wetland were more efficient than the septic tank. P-total reduction was higher in the constructed wetland than in the anaerobic filter. Climatic conditions influenced the evaluated constituent's removal being the highest values during hot months.

European Journal of Energy Research

The exponential population growth will put great pressure on natural resources, agriculture, ener... more The exponential population growth will put great pressure on natural resources, agriculture, energy systems and waste production. New business models and innovative technological approaches are necessary to tackle these challenges and achieve the energy transition targets set by the European Commission. Renewable energy technologies and processes such as solar photovoltaic, solar thermal and anaerobic co-digestion have become a subject of interest and research as a solution that could be fully implemented in industries and solve several environmental and economic problems. This paper discusses the possibility of integrating and complement these technologies to maximize renewable energy production and circularity. The review was performed with a funnel approach aiming to analyze broad to specific subjects. Beginning with a literature review on the various definitions of circular economy, bioeconomy, and circular bioeconomy, ultimately proposing a single definition according to an ind...