Procesos De Bioremediacion Research Papers (original) (raw)

The objective of this study was to evaluate two bioremediation processes at scale (bioaugmentation and biostimulation) isolating and identifying soil-specific bacteria with the ability to bioaccumulate hexavalent chromium (Cr +6), for this we took a sample of 1 kg of soil from an industrial area of León, Guanajuato, from which the bacteria were isolated and identified: Moraxella bovoculi, Acinetobacter rudis, Enterobacter agglomerans, Moraxella bovis, Bulkholderia cepacia and Bulkholderia Mallei. Bioaugmentation was carried out with K2Cr2O7 at a concentration of 540 mg of Cr+6 with the bacteria identified and biostimulation was carried out with the consortium of microorganisms present in the soil with K2Cr2O7 concentration ranges of 440, 540 and 640 mg ofCr+6, using as a reference the NOM-147-SEMARNAT/SSA1-2004, treatments were maintained for 21 days. The biostimulation process was the most efficient for the removal of Cr+6, at a concentration of 640 mg of Cr+ had a maximum removal of 88%, while in the bioaugmentation process the maximum percentage of removal was 28.5 % with a concentration of 540 mg of Cr+ 6. It was determined that the process of biostimulation is the most suitable for the removal of Cr+6.

- by and +1
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- Environmental Remediation, Biotechnology, Environmental Microbiology (Biology), Procesos De Bioremediacion

El cacao (Theobroma cacao) a nivel mundial ha aumentado su área sembrada y rendimiento por hectárea, sin embargo actualmente los productores se enfrentan a una fuerte legislación emanada por la Unión Europea respecto a los contenidos máximos de plomo y cadmio que deben tener los chocolates que contienen una cantidad mayor o igual al 50% de sólidos de cacao. En base a una revisión de los trabajos realizados alrededor del mundo y que han sido publicados en los últimos tres años en bases de datos mundiales se presentan, en primera instancia, los problemas ocasionados en las personas por el consumo de alimentos contaminados por metales pesados y las rutas a través de las cuales se puede contaminar el cacao, desde su siembra hasta su procesamiento. A continuación y dando cumplimiento a el objetivo de la revisión se muestran las técnicas de remediación (ﬁtoremediación y bioremediación) que han obtenido buenos resultados respecto a la limpieza de suelos contaminados o que evitan la traslocación de los contenidos de plomo y cadmio del suelo a varios cultivos de interés comercial para tener opciones de potencial aplicación en las zonas cacaoteras de Colombia o cualquier parte del mundo. De los resultados obtenidos se resalta la importancia que tiene la implementación de un sistema integrado de remediación de suelos que incluya la incorporación gradual de árboles nativos, plantas herbáceas, plantas acuáticas, biochar, bacterias y micorrizas arbusculares.

Carbazole is a nitrogen heterocyclic compound released into the environment, used as a chemical feed stock for the production of dyes, medicines and plastics. Carbazole and their derivatives are detected in atmospheric samples, river sediments, marine water and ground water. Enriched Mineral salts medium (MSM) broth was used to isolate bacteria able to use carbazole as a sole Carbon and Nitrogen and plate assay using MSM agar plate was developed to select carbazole degrading microorganisms. Ten different bacterial isolates were obtained which were capable of utilizing carbazole as the only sole source of carbon and nitrogen added. From the obtained ten isolates C:1, C:2 and C: 3 were from marine water samples, C:4, C:5 and C:6 from marine soil samples, C:7 and C:8 from Pond water samples and C:9, C:10 were from garage soil samples. All isolates were further studied for their "Bioavailability assay" by using different stress and favourable conditions, among all C: 2 isolate showed the maximum considerable and noticeable result in MSM medium. From the bioavailability assay results carbazole degradation studies was carried out using C: 2 isolate by adding 100 ppm and 500 ppm concentration of carbazole in MSM broth medium from which the concentration of carbazole reduced to 8.33 ppm and 50 ppm in 144 hours containing 100 ppm and 500 ppm respectively. Immobilization studies were carried by immobilizing C: 2 isolate in the form of calcium-alginate beads and PVA-alginate beads. Study of Mechanical stability of calcium-alginate and PVA-alginate beads was checked by sonication. PVA-alginate beads were more stable than calcium-alginate beads. Viability of the immobilized cells was tested by calculating colony forming units using both the types of beads, PVA-alginate beads shows more viability than calcium-alginate beads. Carbazole degradation studies with immobilized cells was done by taking absorbance OD600, the concentration reduced to 41.66 ppm and 33.33 ppm in 144 hours using Calcium-alginate beads and PVA-alginate beads respectively containing 100 ppm concentration of carbazole and 241.6 ppm and 120.8 ppm respectively containing 500 ppm concentration of carbazole.

Los procesos de la industria de curtido en la ciudad de León Gto, generan desechos altamente contaminantes (Cr+6) que son vertidos hacia los cuerpos de agua sin un tratamiento eficaz, originando un impacto en el ecosistema acuático y por ende en la salud de la población. Sin embargo, se han propuesto alternativas tecnológicas para el tratamiento del agua contaminada con Cr+6. Entre ellas están el uso de humedales artificiales, tratamientos químicos, y técnicas de adsorción empleando biopolímeros. Esta última técnica ha demostrado ser amigable con el ambiente, sustentable y eficaz. En un trabajo previo se obtuvieron perlas deshidratadas a base de quitosano a nivel laboratorio y se demostró que su obtención depende en gran medida de las características de la materia prima, las concentraciones de los reactivos en las distintas etapas y finalmente, del secado. La presente propuesta de investigación está orientada a sentar las bases para el diseño in silico de una planta piloto con la capacidad de procesar 10 kg de exoesqueleto de camarón por lote y satisfacer así, parcialmente, la demanda a futuro de la industria curtidora.

- by Felipe CL
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- Procesos De Bioremediacion, Biopolimeros

This paper presents an example of the importance of evapotranspiration in constructed wetlands, with vertical subsurface flow, comparing different methods of treatment efficiency calculations and discussing the influence of evapotranspiration on removal rates. The application of reed, marked by high transpiration ability, is a cheap and effective method of landfill leachate disposal. A 2-year study examined the effectiveness of leachate treatment in constructed wetlands with reed. Two kinds of vertical subsurface flow systems: first with sand, and second with combined two layers of sewage sludge and sand has been tested. 1, 3, and 5 mm d−1 hydraulic loading rates of landfill leachate have been applied. Daily evapotranspiration was in the range from 0.98 to 2.99 mm d−1 in the first year of research and from 2.56 to 4.61 mm d−1 in the second year. The influence of evapotranspiration rate on chemical oxygen demand (COD) removal rate was examined. Two methods of removal efficiency calculation have been used: first based on inlet and outlet COD concentrations, second on mass balance determination. Research showed that the removal efficiency calculated as a comparison between initial and final concentration is significantly lower, than expected from mass balance, especially, when higher hydraulic loading rates were applied.

- by Andrzej Białowiec and +1
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- Environmental Engineering, Chemical Engineering, Civil Engineering, Environmental Science

Resumen Esta investigación se la realizó con el fin de evaluar la capacidad de biodegradación de los fenoles presentes en el extracto de tánico de guarango (Caesalpinia spinosa) y en los colorantes índigo carmín, naranja II y rojo fenol, presentes en los desechos de la industria textil. Se utilizaron dos tipos de hongos, el de podredumbre blanca Trametes versicolor y filamentoso Aspergillus niger. Los tratamientos biológicos se aplicaron por triplicado, realizados por el método espectrofotométrico UV por 15 días; los resultados obtenidos al aplicar el hongo Trametes versicolor en el extracto tánico fue del 69,45 % de degradación; y en el colorante índigo carmín fue del 100 % de decoloración. Los resultados de la degradación con el hongo Aspergillus niger sobre el extracto tánico fue del 63,45 % y en el colorante naranja II fue del 32,78 %. En la aplicación de Trametes versicolor y Aspergillus niger sobre el colorante rojo fenol se obtuvieron porcentajes de decoloración no mayores al 26 %. Los hongos aplicados en los tratamientos biológicos presentaron tolerancia tanto a la composición del extracto tánico como a las concentraciones de cada uno de los colorantes usados, esto fue comprobado con la cinética de crecimiento para cada hongo. Abstract This research was done to evaluate phenol biodegradation capacity in Guarango (Caesalpinia spinosa) tannic extract phenols and in indigo carmine, orange II and red phenols, common residues in the textile industry. Two types of fungi were used, white-rot Trametes versicolor fungus and the filamentous Aspergillus niger. Biological treatments were applied in triplicate through the spectrophotometric UV method for 15 days. When applying the Trametes versicolor fungus to the tannic extract, there was 69.45 % degradation, and a 100 % discoloration in the indigo carmine. When applying the Aspergillus niger fungus to the tannic extract and orange II dye, there was a 63,45 % and 32,78 % degradation, respectively. There was a discoloration no greater than 26 % when applying Trametes versicolor and Aspergillus niger to the red phenol. The fungi applied during the biological treatment presented tolerance to both the tannic extract composition as well as the concentration of each dye used, verified through growing kinetics of each fungus.

- by Gaby Méndez
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- Procesos De Bioremediacion

Twenty-three crude-oil-degrading bacteria were isolated from oil-contaminated sites near the Red
Sea. Based on a high growth rate on crude oil and on hydrocarbon degradation ability, four strains
were selected from the 23 isolated strains for further study. These four strains were selected on the
basis of dichlorophenolindophenol assay. The nucleotide sequences of the 16S rRNA gene showed
that these isolated strains belonged to genus Pseudomonas and Nitratireductor. Among the four
isolates, strains S5 (Pseudomonas sp., 95%) and 4b (Nitratireductor sp., 70%) were the most effective
ones in degrading crude oil. Using a spectrophotometer and gas chromatographymass
spectrometry, degradation of more than 90% of the crude oil was observed after two weeks of
cultivation in BushnellHaas medium. The results showed that these strains have the ability to
degrade crude oil and may be used for environmental remediation.

- by Amr A EL Hanafy
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- Procesos De Bioremediacion

Two media bed (gravel and Filtralite NR) were tested in a mesocosm to evaluate the removal of organic matter (as chemical oxygen demand (COD)), ammonia (NH4-N), nitrite, nitrate and solid matter (as total suspended solids (TSS)) for a synthetic wastewater (acetate-based) and a domestic wastewater. The use of Filtralite allowed average removal rates (6–16.8 g COD/(m2·day), 0.8–1.1 g NH4 -N/(m2·day) and 3.1 g TSS/(m2·day)) and removal efficiencies (65%–93%, 57%–85% and 78% for COD, NH4-N and TSS, respectively), higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with higher correlation coefficients for Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to
1.3 g NO3-N/(m2·day). There was no evidence of the influence of nitrate loads on the removal of organic matter.

- by Leonor Amaral and +2
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- Engineering, Environmental Engineering, Chemical Engineering, Civil Engineering

In this study, the effect of some physicochemical parameters on the bioremediation of cadmium (cd 2+) from aqueous solution using Adansonia digitata l. seed cake residue as biosorbent was evaluated. Dried fruits of Adansonia digitata L. were collected from the Department of Biological Sciences, Ahmadu Bello University, Zaria. The seeds were excised, washed with sterile distilled water, sun dried, powdered and defatted using n-hexane to give Adansonia digitata cake residue (ADCR) which was used as the biosorbent. Standard stock solution (30 mg/L) of Cadmium Nitrate Cd(NO 3) 2 was prepared by weighing 30mg of the salt and dissolving in 1L of deionized water this was further diluted for further study. Batch experiments were carried out to study the effect of pH, initial concentration of metal salts, dosage of biosorbent, and contact time. The experimental design was Cross Randomized Design (CRD) and One way Analysis of Variance (ANOVA) was used to determine significant difference among means of the various parameters measured. Duncan Multiple Range Test (DMRT) was used in separating means with different significant values. The level of significance was taken at p < 0.05. The results revealed that the biosorption efficiency increased significantly (p < 0.05) as pH increased from 2-10, initial concentration of metal salt increased from 5-30 mg/L, dosage of biosorbent increased from 50-200mg/L, and as contact time increased from 5-60 min. A maximum biosorption efficiency of 74.25% was observed at a dose of 200mg/L ADCR, initial concentration of metal ion of 30mg/L, pH of 7, and contact time of 60min. From this study Adansonia digitata L. seed could be considered as a potential, eco-friendly, low cost, biosorbent for the removal of Cd 2+ from aqueous solution.

- by António Albuquerque and +1
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- Engineering, Environmental Engineering, Chemical Engineering, Civil Engineering

Biodegradability enhancement and detoxification of cork boiling wastewater (CBW) are required for the successful implementation of biological treatment options. We studied the possibility of achieving these goals through ozonation pre-treatment by experimenting on the effect of ozone dose and pH. The CBW used had a pH of 5.81, a chemical oxygen demand (COD) of 1,865 mg L1, a biochemical oxygen demand (BOD5) of 498 mg L1 and total phenol (TP) and tannin compounds concentrations of 523 and 399 mg L1, respectively. The ozone doses ranged from 0.27 to 2.63 for the O3(applied)/COD0 ratios with samples at natural pH and set to 3.33 and 9.96. Ozonation allowed the BOD20/COD ratio (biodegradability index) to increase from 0.37 to 0.63 and a toxicity reduction from 3.08 to 1.24 TU (Microtox). The corresponding removals obtained were 15.2–62.0%, 38.4–83.2% and 56.7–92.1% for COD, TP and colour, respectively. The best outcome of ozonation pre-treatment requires O3(applied)/COD0 ratios over 1.5 and an acid pH. The increase of TP removals with ozone dose at acid pH led to biodegradability enhancement and CBW detoxification. However, for similar conditions the highest COD removals were obtained at alkaline pH due to the hydroxyl radicals’ high oxidation ability but lack of selectivity.

- by A. Gomes and +2
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- Environmental Engineering, Chemical Engineering, Civil Engineering, Environmental Science

An indole-biotransforming strain MA was identified as Lysinibacillus xylanilyticus on the basis of the 16S rRNA gene sequencing. It transforms indole completely from the broth culture in the presence of an additional carbon source (i.e., sodium succinate). Gas-chromatography-mass spectrometry identified indole-3-acetamide, indole-3-acetic acid, and 3-methylindole as transformation products. Tryptophan-2-monooxygenase activity was detected in the crude extracts of indole-induced cells of strain MA, which confirms the formation of indole-3-acetamide from tryptophan in the degradation pathway of indole. On the basis of identified metabolites and enzyme assay, we have proposed a new transformation pathway for indole degradation. Indole was first transformed to indole-3-acetamide via tryptophan. Indole-3-acetamide was then transformed to indole-3-acetic acid that was decarboxylated to 3-methylindole. This is the first report of a 3-methylindole synthesis via the degradation pathway of indole.

Los plaguicidas alteran el balance de la naturaleza desequilibrando los sistemas ecológicos, este equilibrio es afectado principalmente por los fungicidas y otros productos utilizados directamente sobre el tratamiento del suelo, pues provocan una esterilización (depende del pH y la temperatura) según la cantidad que se agregue de plaguicida y su grado de toxicidad.
El 1,1,1-tricloro-2,2’bis(p-clorofenil)etano (DDT) ha sido usado desde la segunda guerra mundial para controlar enfermedades transmitidas por insectos en humanos y animales domésticos. El uso de estos insecticidas organoclorados se ha prohibido en la mayoría de los países debido a su persistencia en el ambiente, susceptibilidad de biomagnificación y potencial toxicidad a animales superiores.
En muchas zonas del país donde se practica la agricultura intensiva, se hace uso de cualquier tipo de pesticida que puede ayudar a controlar las plagas no teniéndose en cuenta los daños que causan estos productos al suelo. Un grupo de alumnos del Instituto Tecnológico de Toluca decidió realizar un de análisis de suelo con el objeto de conocer la afectación en un área perteneciente al municipio de Malinalco Estado de México para su biorremediación, debido a que sus resultados muestran un alto contenido de DDT, se toma la decisión de dar seguimiento a este trabajo proponiendo un conjunto de técnicas que ayuden a la remediación del sitio.

Cork boiling wastewater pollutants were fractionated by sequential use of four ultrafiltration membranes and five fractions were obtained: four retentates (>100, 50–100, 20–50 and 10–20 kDa) and one permeate (<10 kDa); which were used to study the correlation of molecular size with biodegradability and toxicity before and after ozonation. The results show that molecular size is correlated with organic load and restrains biodegradability. The fraction with >100 kDa corresponds to 56% of the organic load and the one with <10 kDa only 8%. The biodegradability of fractions increased 182% with fractions molecular size reduction from >100 to < 10 kDa and the chemical oxygen demand (COD) was from 3436 to 386 mg L−1. For biodegradability enhancement the best outcome of ozonation was obtained with compounds having molecular size >20 kDa and range from 5% up to 175% for applied ozone doses to COD ratios between 0.15 and 0.38.

- by Antonio Albuquerque and +1
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- Environmental Engineering, Chemical Engineering, Environmental Science, Environmental Economics

Submerged constructed wetlands with sub-surface horizontal flow are suitable systems for wastewater treatment and reuse in small communities. Laboratory studies are a useful way to better understand the evolution of pollutant removal mechanisms
throughout the system. Two Series of experiments were performed in a laboratory microcosms system colonized by Phragmites australis, at the hydraulic loading of 1.67x10-3 m3 m-2 h-1 (approximately 4 cm d-1), organic loading ranging from 10 to 23.4 g m-2 d-1 COD, ammonia nitrogen loading ranging from 1 to 2 g m-2 d-1 NH4-N,
C/NH4-N ratio of 4 and hydraulic retention time of 4.6 d.
The results show an improvement of organic matter and ammonia nitrogen removals rates over time with average values of 7.2 g m-2 d-1 COD and 0.5 g m-2 d-1NH4-N, respectively, a considerable development of the plants and a good adaptation of the biofilm to changes in incoming loading conditions. The higher values of both
removal rates occurred in the initial bed section where the superior DO concentrations allowed the occurrence of aerobic pathways. In the remaining sections (approximately 1.7 m length) the system was DO limiting and the organic removal occurred at lower rates, which seemed to be associated with the prevalence of anaerobic pathways. Although nitrification appears as the most important mechanism of ammonia nitrogen removal, no significant concentration of nitrate nitrogen was detected along the bed, which may be explained by the quick removal of this compound by denitrification. For the range of applied organic and ammonia loadings there was no evidence of a significant variation of the global organic removal rate or the nitrification rate when the incoming characteristics where changed. However, the
nitrification rate at the initial section was in fact affected by changing on incoming loading conditions.

- by Antonio Albuquerque
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- Water, Wetlands, Water quality, Water resources

This work reports new fragments of DNA sequences related to microbes able to degrade phenol into acetate under strict anaerobic conditions. For this purpose, anaerobic digesting sludge was acclimatised to degrade phenol, then heat treated and in turn used as fermentative sludge. The resulting microbial community was able to convert phenol into acetate under anaerobic conditions (kinetic constants: 0.396 ± 0.01 and 0.345 ± 0.04 mg of compound L-1 day-1 , respectively). Microscopic, chemical and molecular analyses revealed that only bacteria were present in the final sludge and thus methanogens were eliminated. The bacteria were mainly Gram-negative sporeforming rods, belonging to the Deltaproteobacteria class and had a tendency for aggregation. These are also phenotypically related to organisms thriving at extreme environments. Cloning, temperature gradient gel electrophoresis (TGGE) and probe matching of a short 16S DNA fragment revealed that these new microbes are evolutionary related to, and share 90% of similarities with, Desulfovibrio sp.

- by Ernesto Hernandez
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- Bioremediation, Biorefinery, Biogas, Bioremediation of wastewater

Background: Chloronitrophenols (CNPs) are widely used in the synthesis of dyes, drugs and pesticides, and constitute a major group of environmental pollutants. 4-Chloro-2-nitrophenol (4C2NP) is an isomer of CNPs that has been detected in various industrial effluents. A number of physicochemical methods have been used for treatment of wastewater containing 4C2NP. These methods are not as effective as microbial degradation, however.

A submerged biologicalaeratedfilter (BAF) partiallyaerated was used to study the removal of lowconcentrations of ammonia nitrogen (0.3 g N/m3 to 30.5 g N/m3) typically found in nutrient enriched river and lake waters, and treated effluents. Four series of experiments were performed with a synthetic wastewater at ammonia loading rates between 6 g N/m3 d and 903 g N/m3 d and C/N ratios from 2 to 20. The results showed that ammonia removal rates reached higher values (172 g N/m3 d to 564 g N/m3 d) for C/N = 2 and lower values (13.6 g N/m3 d to 34.6 g N/m3 d) for C/N = 20. Between 50% and 70% of the ammonia was removed in the upper section of the BAF, where the dissolved oxygen (DO) concentration was over 2.1 g O2/m3 and the biofilm depth ranged from 0.4 to 0.6 mm. At the bottom section of the reactor, simultaneous removal of ammonia and nitrate was observed at the DO concentrations in the range 0.4 g O2/m3 to 0.8 g O2/m3. There was no removal of ammonia nitrogen for loads below 15 g N/m3.d. The results indicate that the removal of nitrogen in partiallyaerated BAF may not only be explained by the conventional mechanisms of nitrification/denitrification.

8 Abstract 9 The effects of technical grade hexachlorocyclohexane (tech-HCH) on the germination of different seeds were tested. 10 Two types of seeds, radish and green gram showed marked reduction in germination percentage and seeding vigour 11 index. The abnormalities and reduction in germination increased with increasing concentration of tech-HCH. At 100 lg 12 HCH level the germination of radish and green gram seeds was inhibited almost completely on moist filter paper and 13 soil. Protease and amylase activities were reduced in seeds grown in soil spiked with tech-HCH. Bioremediation of 14 HCH-spiked soils with a HCH-degrading microbial consortium helped in eliminating the toxic effects of tech-HCH 15 towards seed germination. The degradation of 25 lg tech-HCH g À1 soil was complete by 120 h. The seed germination 16 and the activities of the assayed enzymes, amylase and protease, were same as before or better in bioremediated soils. 17

- by Aracely Maldonado-Torres
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- Bioremediation, Procesos De Bioremediacion
- by Andrzej Białowiec and +1
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- Engineering, Environmental Engineering, Chemical Engineering, Civil Engineering

Arthrobactersp.SPGutilized2-nitrobenzoateasitssolesourceofcarbonandenergyanddegradeditwithaccumulationofstoichiometricamountsofnitriteions.Salicylateandcatecholweredetectedasmetabolitesofthe2-nitrobenzoatedegradationusinghighperformanceliquidchromatographyandgaschromatography–massspectrometry.Enzymeactivitiesfor2-nitrobenzoate-2-monooxygenase,salicylatehydroxylase,andcatechol-1,2-dioxygenaseweredetectedinthecrudeextractsofthe2-nitrobenzoate-inducedcellsofstrainSPG.The2-nitrobenzoate-monooxygenaseactivityresultedinformationofsalicylateandnitritefrom2-nitrobenzoate,whereassalicylatehydroxylasecatalyzedtheconversionofsalicylatetocatechol.Thering-cleavingenzyme,catechol-1,2-dioxygenasecleavedcatecholtocis,cis-muconicacid.CellsofstrainSPGwereabletodegrade2-nitrobenzoateinsterileaswellasnon-sterilesoilmicrocosms.TheresultsofmicrocosmstudiesshowedthatstrainSPGdegradedmorethan90%of2-nitrobenzoatewithin10–12days.ThisstudyclearlyshowsthatArthrobactersp.SPGdegraded2-nitrobenzoateviaanewpathwaywithformationofsalicylateandcatecholasmetabolites.Arthrobactersp.SPGmaybeusedforbioremediationof2-nitrobenzoate-contaminatedsitesduetoitsabilitytodegrade2-nitrobenzoateinsoil.

Nitrate removal from water has been accomplished by heterotrophic biofilms using organic carbon as a source of reducing power. To overcome the natural limitation in organic carbon in water, a poly-ε-caprolactone based biofilm carrier that serves simultaneously as a biofilm carrier and as a source of organic carbon was developed and tested in the present work. The feasibility of the new biofilm carrier for nitrate removal from water was evaluated in a packed bed reactor. The combination of size and structure provided a carrier element having high surface area and void volume, 1,170 m2/m3 and 67 %, respectively. A maximum denitrification rate of 4.4 mg N–NO3 −/(L.h) (9.2 mg N–NO3 −/(m2.h)) was achieved in the packed bed reactor at 20 °C and pH 7.0. Main advantages of the biofilm carrier developed in the present work are its mechanical stability in water even after biofilm formation and controlled release of organic carbon by enzymatic reactions. The proposed biotechnology to remove nitrate from groundwater is robust and easy to operate.

- by Antonio Albuquerque and +1
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- Environmental Engineering, Polymer Engineering, Chemical Engineering, Civil Engineering