Wet anaerobic digestion of organic fraction of municipal solid waste: experience with long-term pilot plant operation and industrial scale-up.

This paper presents the analysis of a pilot anaerobic digestion plant that operates with organic fraction of municipal solid waste (OFMSW) from a wholesale market and can treat up to 500 kg d-1. The process was monitored for a period of 524 days during which the residue was characterized and the biogas production and methane content were recorded. The organic load rate (OLR) of volatile solids (VS) was 0.89 kg m-3 d-1 and the Hydraulic Retention Time (HRT) was 25 d during the process. The yield was 82 Nm3 tons OFMSW-1 biogas, equivalent to 586 Nm3 tons CH4 VS-1. The results obtained in the pilot plant were used to carry out a technical-economic evaluation of a plant that treats 50 tons of OFMSW from wholesale markets. A production of 3769 Nm3 d-1 of biogas and 2080 Nm3 d-1 of methane is estimated, generating 35.1 MWh d-1 when converted to electricity.

Instrumented open-source filament extruder for research and education.

Extruders are necessary equipment for 3D filament manufacturing, which is considered a clean technology because it has less scrap and can reuse materials, increasing its life cycle. Open source extruders are less expensive than industrial extruders. However, they have little instrumentation, which limits processing analysis and thus the development of new materials, screw design and process control. Therefore, this project aims to develop a low-cost extruder with a high degree of instrumentation for in-situ process analysis. To achieve this, equipment was developed with an integrated circuit board, both with modularity, machine and peripheral control, process stability, and data acquisition. To validate the equipment, processing was done at constant temperature and with flow variation. The data obtained were the temperatures at different points in the barrel, the rotation speed of the extruder motor, the current consumed by the motor and the resistances, and the speed of the extruder motor. Thermal images of the components were obtained during processing, validating the type of material used in the parts manufactured by additive manufacturing. The ABS filament produced was analyzed by flow and surface analysis using a confocal microscope. Higher flow rates had a better surface quality of the filament.

Development of an economically competitive Trichoderma-based platform for enzyme production: Bioprocess optimization, pilot plant scale-up, techno-economic analysis and life cycle assessment.

Despite decades of research and industrial applications of Trichoderma reesei, the development of industrially relevant strains for enzyme production including a low-cost and scalable bioprocess remains elusive. Herein, bioprocess optimization, pilot plant scale-up, techno-economic analysis and life-cycle assessment for enzyme production by an engineered T. reesei strain are reported. The developed bioprocess increased in âˆ¼ 2-fold protein productivity (0.39 g.L-1.h-1) and 1.6-fold FPase activity (196 FPU.L-1.h-1), reducing the fermentation in 4 days. Cultivation in a 65-L pilot plant bioreactor resulted in 54 g.L-1 protein in 7 days, highlighting the robustness and scalability of this bioprocess. Techno-economic analysis indicates an enzyme cost of âˆ¼ 3.2 USD.kg-1, which is below to the target proposed (4.24 USD.kg-1) in the NREL/TP-5100-47764 report, while life-cycle assessment shows a carbon footprint reduction of approximately 50% compared to a typical commercial enzyme. This study provides the fundamental knowledge for the design of economically competitive Trichoderma technologies for industrial use.

Evaluation of zinc adsorption through batch and continuous scale applying Bayesian technique for estimate parameters and select model.

This work aims to study the efficiency of zinc adsorption onto granular-activated carbon, predicting the mathematical models that best describe the adsorption behavior in a fixed bed column. First, batch scale experiments were performed to evaluate the influence of pH (3 to 6), contact time (5 to 60 min), and absorbent concentration (5 to 25 g L-1) using synthetic effluent. Fixed bed column experiments were performed by varying the adsorbent concentration (10, 13, 20, and 40 g L-1) and the effluent flow rate (15 and 20 mL min-1). Markov Chain Monte Carlo and Bayesian criteria information were applied to describe the phenomena using Langmuir, Freundlich, Temkin, Redlich-Peterson, Sips, Toth, Khan, Radke-Prausnitz, for isotherm models, and Thomas; Yoon-Nelson; Yan; Clark models for breakthrough curve. Adsorption operating best conditions were pH 5, 20 g L-1 of solid, and 50 min of contact time. These parameters allowed 80% of Zn removal, being better described by the Tempki model. In tests on a pilot plant, the Yan model was able to predict the second-order kinetic model, with an increase in the effluent flow and a 50% increase in the bed saturation time with a greater amount of adsorbent solid.

Pilot-plant scale extraction of phenolic compounds from grape canes: Comprehensive characterization by LC-ESI-LTQ-Orbitrap-MS.

Grape canes, also named vine shoots, are well-known viticultural byproducts containing high levels of phenolic compounds, which are associated with a broad range of health benefits. In this work, grape canes (Vitis vinifera cv. Pinot noir) were extracted in a 750 L pilot-plant reactor under the following conditions: temperature 80 °C, time 100 min, solid/liquid ratio 1:10. The comprehensive characterization of grape cane phenolic compounds was performed by liquid chromatography coupled to high-resolution/accurate mass measurement LTQ-Orbitrap mass spectrometry. A total of 44 compounds were identified and, 26 of them also quantified, consisting of phenolic acids and aldehydes (17), flavonoids (12), and stilbenoids (15). The most abundant class of phenolics were stilbenoids, among which (E)-ε-viniferin predominated. The phenolic profile of grape canes obtained using pilot plant extraction differed significantly from the results of laboratory-scale studies obtained previously. Additionally, we observed a high antioxidant capacity of grape cane pilot-plant extract measured by the radical antioxidant scavenging potential (ABTS+) (2209 ± 125 µmol TE/g DW) and oxygen radical absorbance capacity using fluorescein (ORAC-FL) (4612 ± 155 µmol TE/g DW). Grape cane pilot-plant extract for their phenolic profile may be used as a by-product for the development of novel nutraceutical and pharmaceutical products, improving the value and the sustainability of these residues.

Experimental data on activity catalyst TiO2/Fe3O4 under natural solar radiation conditions.

In this document, the photocatalytic activity of TiO2/Fe3O4, prepared by the mixing of the pure oxides, was studied. The photocatalytic degradation of aqueous Methylene Blue (MB) solutions (10 and 30 ppm) was performed, the TiO2/Fe3O4 catalysts in 80/20, 50/50 and 20/80 mass ratios were used during the test, artificial sunlight and natural solar radiation were tested at laboratory and pilot plant scale respectively. Besides, the kinetic reactions were evaluated according to the Langmuir-Hinshelwood model, the apparent velocity constants (kapp) were obtained for the TiO2/Fe3O4 catalysts. In the laboratory test, the TiO2/Fe3O4 catalyst (80/20) had a performance for 93.04% of discoloration, kapp = 0.0238 min-1, while for TiO2/Fe3O4 (50/50, 20/80) had an 83.46%, 65.00% for discoloration of MB and the kapp values were 0.0154 min-1 and 0.0098 min-1, respectively. In the solar test at pilot scale, the percentages of discoloration of 24.32%, and 57.78%, with kapp values of 0.00037 min-1, 0.00121 min-1 respectively were obtained for TiO2/Fe3O4 (80/20), a MB solution of 30 ppm, a load of 0.1 g/L and 0.3 g/L of the catalyst respectively.

Elimination of Escherichia coli in Water Using Cobalt Ferrite Nanoparticles: Laboratory and Pilot Plant Experiments.

This paper focuses on the synthesis of cobalt ferrite nanoparticles by the sol-gel method and their photocatalytic activity to eliminate bacteria in aqueous media at two different scales: in a laboratory reactor and a solar pilot plant. Cobalt ferrite nanoparticles were prepared using Co(II) and Fe(II) salts as precursors and cetyltrimethyl ammonium bromide as a surfactant. The obtained nanoparticles were characterized by X-ray diffraction, scanning and transmission electron microscopy. Escherichia coli (E. coli) strain ATCC 22922 was used as model bacteria for contact biocidal analysis carried out by disk diffusion method and photocatalysis under an ultraviolet A (UV-A) lamp for laboratory analysis and solar radiation (radiation below 350 W/m2 in a typical cloudy day) for the pilot plant analysis. The results showed that cobalt ferrite nanoparticles have an average diameter of (36 ± 20) nm and the X-ray diffraction pattern shows a cubic spinel structure. Using the disk diffusion technique, it was obtained inhibition zones of (17 ± 2) mm diameter. Results confirm the photocatalytic elimination of E. coli in water samples with remaining bacteria below 1% of the initial concentration during the experiment time (30 min for laboratory tests and 1.5 h for pilot plant tests).

Factorial and Economic Evaluation of an Aqueous Two-Phase Partitioning Pilot Plant for Invertase Recovery From Spent Brewery Yeast.

Aqueous two-phase systems (ATPS) have been reported as an attractive biocompatible extraction system for recovery and purification of biological products. In this work, the implementation, characterization, and optimization (operational and economic) of invertase extraction from spent brewery yeast in a semi-automatized pilot plant using ATPS is reported. Gentian violet was used as tracer for the selection of phase composition through phase entrainment minimization. Yeast suspension was chosen as a complex cell matrix model for the recovery of the industrial relevant enzyme invertase. Flow rates of phases did not have an effect, given that a bottom continuous phase is given, while load of sample and number of agitators improved the recovery of the enzyme. The best combination of factors reached a recovery of 129.35 ± 2.76% and a purification factor of 4.98 ± 1.10 in the bottom phase of a PEG-Phosphate system, also resulting in the removal of inhibitor molecules increasing invertase activity as reported by several other authors. Then, an economic analysis was performed to study the production cost of invertase analyzing only the significant parameters for production. Results indicate that the parameters being analyzed only affect the production cost per enzymatic unit, while variations in the cost per batch are not significant. Moreover, only the sample load is significant, which, combined with operational optimization results, gives the same optimal result for operation, maximizing recovery yield (15% of sample load and 1 static mixer). Overall res ults of these case studies show continuous pilot-scale ATPS as a viable and reproducible extraction/purification system for high added-value biological compounds.

Mineralization of the textile dye acid yellow 42 by solar photoelectro-Fenton in a lab-pilot plant.

A complete mineralization of a textile dye widely used in the Chilean textile industry, acid yellow 42 (AY42), was studied. Degradation was carried out in an aqueous solution containing 100mgL(-1) of total organic carbon (TOC) of dye using the advanced solar photoelectro-Fenton (SPEF) process in a lab-scale pilot plant consisting of a filter press cell, which contains a boron doped diamond electrode and an air diffusion cathode (BDD/air-diffusion cell), coupled with a solar photoreactor for treat 8L of wastewater during 270min of electrolysis. The main results obtained during the degradation of the textile dye were that a complete transformation to CO2 depends directly on the applied current density, the concentration of Fe(2+) used as catalyst, and the solar radiation intensity. The elimination of AY42 and its organic intermediates was due to hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between electrogenerated H2O2 and added Fe(2+). The application of solar radiation in the process (SPEF) yield higher current efficiencies and lower energy consumptions than electro-Fenton (EF) and electro-oxidation with electrogenerated H2O2 (E OH2O2) by the additional production of hydroxyl radicals from the photolysis of Fe(III) hydrated species and the photodecomposition of Fe(III) complexes with organic intermediates. Moreover, some products and intermediates formed during mineralization of dye, such as inorganic ions, carboxylic acids and aromatic compounds were determined by photometric and chromatographic methods. An oxidation pathway is proposed for the complete conversion to CO2.

Recovery of different waste vegetable oils for biodiesel production: a pilot experience in Bahia State, Brazil.

In Brazil, and mainly in the State of Bahia, crude vegetable oils are widely used in the preparation of food. Street stalls, restaurants and canteens make a great use of palm oil and soybean oil. There is also some use of castor oil, which is widely cultivated in the Sertão Region (within the State of Bahia), and widely applied in industry. This massive use in food preparation leads to a huge amount of waste oil of different types, which needs either to be properly disposed of, or recovered. At the Laboratorio Energia e Gas-LEN (Energy & Gas lab.) of the Universidade Federal da Bahia, a cycle of experiments were carried out to evaluate the recovery of waste oils for biodiesel production. The experiences were carried out on a laboratory scale and, in a semi-industrial pilot plant using waste oils of different qualities. In the transesterification process, applied waste vegetable oils were reacted with methanol with the support of a basic catalyst, such as NaOH or KOH. The conversion rate settled at between 81% and 85% (in weight). The most suitable molar ratio of waste oils to alcohol was 1:6, and the amount of catalyst required was 0.5% (of the weight of the incoming oil), in the case of NaOH, and 1%, in case of KOH. The quality of the biodiesel produced was tested to determine the final product quality. The parameters analyzed were the acid value, kinematic viscosity, monoglycerides, diglycerides, triglycerides, free glycerine, total glycerine, clearness; the conversion yield of the process was also evaluated.