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This article shows the effect that biogases obtained from crop residuals from the Andean region have on the performance of a whole medium-sized electrical-generating gas turbine. This technology could be used to supply electricity in energy-depressed areas where biogas is the only accessible resource. The gas turbine worked with higher efficiencies when the obtained biogases were used compared to natural gas. The biofuel that presented the highest efficiencies was the one obtained from wheat residuals alone. Despite this fact, this biofuel would be the most prone to create aerodynamic problems in the stages of the gas turbine. In this work, it was found that the addition of guinea pig manure to different crop residuals created biofuels less prone to create aerodynamic problems in the compression and expansion stages. In particular, the studied biofuel that had the most similar aerodynamic behavior to the design natural gas case was the one obtained from guinea pig manure and quinoa residuals. On the other hand, this biogas presented the lowest efficiencies of the studied biofuels. Despite this fact, this biofuel showed higher efficiencies than the natural gas case. In the gas turbine combustion chamber, all the studied biofuels operated at lower temperatures than the ones with natural gas, even in the high-power range. This would be an important feature for the running of the combustion chamber and the high-pressure turbine superalloys.

The objective of this research was to evaluate the anaerobic co-digestion of guinea pig manure (CY) with Andean agricultural residues such as amaranth (AM), quinoa (QU) and wheat (TR) in batch biodigesters under mesophilic conditions (37⁰C) for 40 days. As microbial inoculum, sewage treatment sludge was used in two inoculum/substrate ratios (ISR of 1 and 2). In terms of methane production, the best results occurred in the treatments that contained AM and QU as co-substrate and an ISR of 2. Thus, the highest methane production occurred in the CY:AM biodigesters (25:75) and CY:QU (25:75) with 341.86 mlCH4/g VS and 341.05 mlCH4/g VS, respectively. On the other hand, the results showed that methane production with an ISR of 2 was more feasible for guinea pig waste, where the methane fraction of the biogas generated was in a range of 57 and 69%. The kinetics of methane production from these raw materials was studied using five kinetic models: modified Gompertz, logistic equation, transfer, cone, and Richards. The cone model was the one that best adjusted the experimental values ​​with those observed with an r2 of 0.999 and an RMSE of 1.16 mlCH4/g VS. Finally, the highest biodegradability was obtained in the CY-AM biodigesters (25:75) with 67.92%.

This study aims to evaluate the effects of the co‐digestion of agricultural residues with manure from camelids from the Andean zone. Different combinations of llama manure (LM) and vicuñas (VM) were made with amaranth (AS), quinoa (QS), and wheat (WS) residues. They were fermented using sewage sludge as inoculum. The co‐digestion was evaluated under mesophilic conditions for 40 days. The ratios of volatile substances of substrate / co‐substrate evaluated were 0:100; 25:75; 50:50, 75:25, and 100:0. Two substrate / inoculum ratios (SIR 1:1 and SIR1:2) were also evaluated. The results indicate that the maximum methane accumulation rate is obtained in SIR 1:1 for a VM‐AS ratio (25:75) with 540 mL/g volatile solid (VS). In general, the results did not increase with the increase in inoculum; rather, the tendency to improve methane yield is associated with an increase in the amount of agricultural residues, mainly AS. Regarding the kinetic modeling, the transfer model is the one that best adjusted the predicted values to those observed with an r2 between 0.991 and 0.999, and an RMSE value between 2.06 and 13.62 mL/g (volatile solid) VS. Finally, all the trials presented synergistic effects in their co‐digestion except the digesters formed by LM‐AS, LM‐QS and LM‐WS of SIR 1:2. These presented antagonistic effects in which the addition of the co‐substrate generated competition with the substrates, reducing methane production. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

The objective of this research is to experimentally evaluate the anaerobic co-digestion of slaughterhouse residues in the city of Guaranda with straw residues from agriculture, such as: amaranth, quinoa and wheat. The study was carried out on a laboratory scale using 311 ml biodigesters under mesophilic conditions of 37 °C. Anaerobic co-digestion resulted in methane yields of 407 ml CH4/g VS, with a methane content in the biogas of 77% for the mixture of slaughterhouse waste and quinoa (RM-QU (25:75)). The increase in inoculum in the mixtures composed of slaughterhouse residues and quinoa increased the biodegradability between 17 and 22%. However, in the mixtures of slaughterhouse waste and amaranth (RM-AM (0:100)), a further increase in inoculum decreased biodegradability by 5%. To predict and simulate methane production, 5 kinetic models were used: modified Gompertz, logistic equation, transfer, cone and Richards. The cone model was the one that best adjusted the experimental values ​​with those predicted with an R2 of 0.982 to 0.999 and RMSE of 0.61 to 6.92 ml CH4/g VS. The calculation of the theoretical yield was carried out by stoichiometry and elemental analysis of the samples. Theoretical yields ranged between 480-564 ml CH4/g VS for all mixtures of RM with agricultural residues.

This paper evaluates the anaerobic digestion of agricultural waste, manure and slaughterhouse residues of species typical of the Andes, such as llama, vicuna and guinea pig; quinoa, amaranth and wheat straw in order to be able to use them as a renewable energy source and boost rural development in the region. Has been used sludge from a WWTP as inoculum, evaluating the effect of two relationships between the substrate and inoculum (RSI) for both livestock and agricultural waste. The highest cumulative maximum methane production rate was obtained for the residues of flame manure and quinoa straw for an RSI of 1:2 with productions of 376.08 ml CH4/g SV and 377.02 ml CH4/g SV respectively. In these materials an RSI of 1:2 obtained increases of 22.56% and 37.54% compared to the RSI 1:1. Also, the kinetic analysis showed that the modified Gompertz model is the one that best fits performance, with constant differences of 7.06% between the experimental and predicted values. On the other hand, the modified Gompertz model was adjusted to the experimental results with an r2 of (0.998) and an RMSE of 4.09 ml/g SV at 17.12 ml/g SV.

In this work, a new approach to evaluating the amount of residual biomass obtained from orange trees based on normalization of variables is proposed for Bolivar province, Ecuador. So far, several models to quantify the amount of residues obtained from pruning have been proposed from dendrometric and cultivation variables, such as height, crown diameter, stem diameter, area per plant, yield, and age. However, the high dispersion of their values, caused by uncontrolled conditions, gave models with a low-medium coefficient of determination. The aim of this work has been to develop several models in order to predict wet available biomass using dimensionless dendrometric parameters from height, diameter and height of the crown, and the stem height. They improved the coefficients of determination to 0.94 for the global mathematical model. The drying process of pruned materials has also been analyzed. Residual biomass with 50% initial moisture content was dried outdoors on cement and agricultural soil until it reached constant moisture content. Models used to describe the drying process of agricultural products were employed to fit the observed data of the drying process of orange tree chips. Among the tested models, the Midili and Page models were those that best fitted the observed data in the drying process. The information offered by these equations is of vital importance because they help estimate the amount of biomass that is generated in a given area, and the implementation geographic information system (GIS) maps. In addition, logistic algorithms can be applied. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

[EN] The use of biomass raw material from agricultural areas is a challenge for Ecuatorian government. However there is lack information about surveying systems and processing in its height and weather conditions. The objective of this work was to develop methods to quantify straw residues, easily applicable in corn areas of Guaranda (Ecuador), and model the drying process at different air conditions. Two dendrometric equations were obtained for predicting dry available biomass by stem and cultivated area respectively, from corn mean height and radius of the stem. High coefficients of determination were obtained (0.94 and 0.97 respectively). Straw chips with initial moisture content ranging from 70 to 80% with an average moisture content of 76.7% wet basis were dried until they reached constant moisture content. Traditional models used to describe the drying process of agricultural products were employed to fit the observed data of the drying process of straw corn chips. Among the tested models, the Midili, Page, and sigmoid model were those that best fit the observed data representing the drying process. The effective diffusion (Def) was determined by means of an analytical solution of Fick's second law. Effective moisture diffusivity values obtained at natural outdoor drying conditions were 2.443E-11 and 2.035E-10 m2/s, for the first and second falling periods, respectively., The participation of Dr. Sergio Perez and Dr. Zulay Nino-Ruiz in this work was possible by funding from the Ecuadorian Government by means of PROMETEO program, leaded by the Secretaria Nacional de Educacion Superior, Ciencia y Tecnologia (SENESCYT).

Background: This research addressed the topic of timely diagnosis of Helicobacter pylori that is currently a problem for public health in Ecuador and worldwide. The prevalence of the pathogen has increased in the last decade, especially due to its direct participation in gastric cancer generation. Objectives: The present investigation was carried out to detect H. pylori in human stool samples by antigenic screening and culture. Methods: The methodology used in this study was direct and indirect analysis of patients with H. pylori infection symptoms. Overall, 50 stool samples were collected (16 from males and 34 from females) and transferred immediately to the laboratory; patients were excluded due to causes such as contamination or insufficient amounts of sample for the analysis. From these samples, antigenic screening and culture in plates were carried out using the Brucella blood agar selective medium under controlled conditions. The two methods were analysed using the Kappa coefficient. Results: After antigenic screening analysis, 25 samples (50%) were positive for H. pylori with four false positives for both genders. The culture results showed that 19 samples (38%) were positive with 32 isolates characteristic for H. pylori. After agreement analysis, the kappa index was 0.28 (discrete). Conclusions: The detection rate by antigenic screening was higher than that obtained by culture, this is mainly due to the lack of viable cells and the difficulty of adapting adequate isolation techniques.

[EN] For the economically depressed communities such as of those in the Canton Guaranda, Ecuador, to generate their own energy, from organic waste is very important because they are sometimes insulated and its gas and electricity supply is very deficient. The aim of this research, was to determine the feasibility of anaerobic co-digestion of wasted cabbage from the town's market in Guaranda, Ecuador, and livestock manure. Two variables were studied: temperature of the process and the percentage of cabbage and livestock manure. Biogas quantity and kinetic parameters were evaluated. Kinetic model were analyzed by minimizing the mean percentage of error between the observed values (measured experimentally) and predicted, using the Runge-Kutta of order 4 for solving the system of differential equations obtained from mass balance. The results showed that a 50-50% ratio cabbage-manure at 30 degrees C temperature gave the highest production of biogas achieved is (389.47cm(3)N/g initial SV) with a composition of 61% methane. The kinetic parameters found were mu(max)=0.1053day(-1); Ks=0.1153mg/l; Y=0.00246g VSS /g COD and K-dec=0.001005day(-1)., This research work has been carried out inside the cooperation framework funded by the ADSIDEO program of the Centro de Cooperacion al Desarrollo (CCD) of Universidad Politecnica de Valencia (Spain), in collaboration with the Centro de Estudios de la Biomasa (CEB), Universidad Estatal de Bolivar, Guaranda, Ecuador. The participation of Dr. Sergio Perez in this work was possible thanks to funding from the Ecuadorian Government by means of the PROMETEO program, led by the Secretaria Nacional de Educacion Superior, Ciencia y Tecnologia (SENESCYT).

Bioethanol production from sugarcane represents an opportunity for urban-agricultural development in small communities of Ecuador. Despite the fact that the industry for bioethanol production from sugarcane in Brazil is fully developed, it is still considered expensive as a small rural business. In order to be able to reduce the costs of monitoring the production process, and avoid the application of expensive sensors, the aim of this research was modeling the kinetics of production of bioethanol based on direct measurements of Brix grades, instead of the concentration of alcohol, during the process of cane juice bio-fermentation with Saccharomyces cerevisiae. This avoids the application of expensive sensors that increase the investment costs. Fermentation experiments with three concentrations of yeast and two temperatures were carried out in a laboratory reactor. In each case Brix grades, amount of ethanol and alcoholic degree were measured. A mathematical model to predict the quality and production of bioethanol was developed from Brix grade measurements, obtaining an adjusted coefficient of determination of 0.97. The model was validated in a pilot plant.