E. Santoyo

E. Santoyo
Universidad Nacional Autónoma de México | UNAM · Institute for Renewable Energy

Doctor of Philosophy

About

132
Publications
45,770
Reads
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2,283
Citations
Citations since 2016
19 Research Items
979 Citations
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
Additional affiliations
May 2013 - August 2015
Universidad Nacional Autónoma de México
Position
  • Leader of the Geoenergy Group
May 2013 - November 2015
Universidad Nacional Autónoma de México
Position
  • Leader of the Geoenergy Group
January 2013 - June 2015
Universidad Nacional Autónoma de México
Position
  • Head of Department, Energy Systems and Leader of the Geoenergy Group
Education
October 1994 - November 1997
University of Salford
Field of study
  • Thermal Energy - Geothermal Energy

Publications

Publications (132)
Article
A new integrated methodology to estimate environmental impacts of bioethanol production from sugarcane bagasse was developed for Mexico. The methodology included five modelling phases: (i) a bibliometric analysis and systematic literature review using peer-review journals, and world citation databases; (ii) a simulation of the gasification process...
Poster
Study area IER-UNAM Geoenergy Research Group Table 1. Statistical parameters of soil CO2 flux measurements [lnCO2 (gm-2d-1)] at Acoculco Caldera. S The increase of geothermal energy production in Mexico has promoted intense exploration surveys for exploiting hidden geothermal systems (HGS) in the future. Previous geothermal exploration at Acoculco...
Preprint
Full-text available
Chemical, isotopic and thermal signatures, space-temporal concentration patterns, and geochemical conceptual models are used to gather insights of the internal structure of geothermal reservoirs. These investigations rely on historical and latest data dealing with the composition of the geothermal fluids discharged from either producer wells or sur...
Article
Full-text available
A geochemometric study based on a multi-criteria decision analysis was applied, for the first time, for the optimal evaluation and selection of artificial neural networks, and the prediction of geothermal reservoir temperatures. Eight new gas geothermometers (GasG 1 to GasG 8 ) were derived from this study. For an effective and practical applicatio...
Article
A first life cycle assessment study for the evaluation of a grid-connected photovoltaic system in Mexico was carried out from a cradle-to-grave perspective. The photovoltaic system consists of 12 modules integrated with a multi-crystalline silicon technology with a southward inclination of 20°, a 2.5 kW inverter, and a total installed capacity of 3...
Article
A geochemical mapping of rare earth (REE) and other trace elements in water and rock samples of the hidden geothermal system of the Acoculco caldera was carried out. REE and other trace elements were measured at low concentrations in waters (ΣREE <50 μg/L) and rocks (ΣREE <773 μg/g), and used, for the first time, to understand the water-rock intera...
Conference Paper
The study of water-rock interaction (WRI) processes through an integral modelling of fluid and rock geochemistry is being used as a new geochemometric tool for the prospection of the hidden Geothermal System of Acoculco (GSA) located in the state of Puebla, Mexico. The results of a comprehensive WRI study carried out at GSA are reported for elucida...
Article
Most of the volcanic rocks in the Acoculco geothermal system (AGS), near to the surface manifestations, are intensively altered. Thirty‐four surface volcanic rocks and five rocks from outcrop sections are considered in this work. Silica polymorphs (quartz, cristobalite and tridymite) are the dominant hydrothermal minerals in almost all the rock sam...
Article
Environmental impacts of an experimental Solar Absorption Air-Conditioning System based on a Life- Cycle Assessment were evaluated for the first time in Mexico. For comparison, a Commercial Air Conditioning System that uses electricity from fossil fuels was also evaluated. In both cooling systems, the construction, operation and end-of-life stages...
Article
Three-layer artificial neural networks were used for the multivariate analysis of the gas-phase composition of fluids, and the prediction of geothermal reservoir temperatures. The major gas-phase composition of geothermal fluids (CO2, H2S, CH4, and H2) was defined as input variables whereas the measured bottomhole temperatures were used as output....
Article
Drill rock cuttings from different depths of two geothermal wells (Az-26 and Az-49) from the Los Azufres Geothermal Field (LAGF), Mexico, were analyzed for rock magnetic properties (magnetic susceptibility, χ lf ; frequency-dependent susceptibility, χ fd; susceptibility of anhysteretic remanent magnetization, χ ARM ; isothermal remanent magnetizati...
Article
Acquiring thermophysical properties of rock-formations in geothermal systems is an essential task required for the well drilling and completion. Wellbore thermal simulators require such properties for predicting the thermal behavior of a wellbore and the formation under drilling and shut-in conditions. The estimation of static formation temperature...
Article
To celebrate the 30th anniversary of the establishment of Universidad Nacional Autonoma de Mexico (UNAM) in Temixco, Morelos, and to continue promoting the use of renewable energy and sustainability strategies, the Third Edition of the International Symposium on Renewable Energy and Sustainability (ISRES 2015) was once more organized at the Institu...
Article
In this work, an analysis of production data for determining the damage effect in geothermal wells is reported. Measurements of some Mexican geothermal wells have been analyzed for evaluating the decrease of their productivity under exploitation conditions. As an innovation of the methodology used in this work, the dimensionless well flow parameter...
Article
The market of energy production coming from geothermal energy is growing around the world. However, in some countries little attention is given to the life cycle environmental impacts of this industrial sector. In addition to the available work presented in previous reviews about this matter, this paper provides an updated review of life cycle envi...
Article
Full-text available
A new practical method based on logarithmic transformation regressions was developed for the determination of static formation temperatures (SFTs) in geothermal, petroleum and permafrost bottomhole temperature (BHT) data sets. The new method involves the application of multiple linear and polynomial (from quadratic to eight-order) regression models...
Article
Full-text available
Hydrogen (H2) production from experiments with Spirulina maxima 2342 is reported in this work. The performance of this photosynthetic microorganism for producing H2 was evaluated for the first time under specific experimental conditions (e.g., a biomass concentration of 0.34 ± 0.02 g, a light intensity of 150 μE.s-1.m-2 and reaction times of 19.3 ±...
Poster
Full-text available
Geothermal energy is an important renewable energy resource in Mexico, and the evaluation of the energy potential of promising geothermal systems has been defined as an important task for defining the future energy portfolio of the country. For achieving such general goal, a preliminary geochemical study for the evaluation of promissory geothermal...
Article
Water/Rock Interaction (WRI) experiments, Na-K geothermometry and geochemometrics modeling have been used for the study of the kinetic behavior of the volcanic rock dissolution under geothermal conditions. Ionic exchange reactions between Na-K and alkaline-feldspar minerals were monitored at 90 degrees C and 150 degrees C for a period of nearly 24...
Article
In commemoration of the 2012 International Year of Sustainable Energy for All, declared by United Nations, and also for continuing with the use of renewable energy and sustainability strategies, the Institute for Renewable Energy (in Spanish "Instituto de Energias Renovables", IER) of the Universidad Nacional Autenoma de Mexico [UNAM; formerly Cent...
Article
Deep reservoir temperatures of 10 important geothermal systems of the world were estimated by applying 13 solute (Na/K) and 21 gas geothermometers. The predicted temperatures were comprehensively evaluated and compared with measured bottom-hole temperatures using geochemometric techniques. The present study reveals (1) high prediction performances...
Article
In a previous work, one-dimensional numerical modelling of fluid-flow inside short tube orifices was performed, and successfully validated against a wide range of mass flow rate measurements reported for the refrigerant HFC-134a. Governing equations of continuity, momentum, energy and entropy were solved for describing the fluid flow under a wide v...
Data
Full-text available
Systematic radon measurements have been carried out at two high heat-producing wells in the geothermal field of Los Azufres Michoacan, Mexico. Both wells are located close to active faults across of which radon data in soil is also obtained. Radon content in geotermal fluids from producing energy wells shows to be strongly correlated with enthalpy
Article
Full-text available
A multivariate analysis using ortificial neural networks for determining the relative contribution of the cationic composition of fluids (Na, K, Mg, Ca and Li) for the estimation of downhole temperatures of geothermal wells is here reported. Neural architectures were evaluated using different numerical techniques of training, activation function lo...
Article
Full-text available
A comparative study of the reservoir fluid characteristics calculation of ten production wells of Los Azufres, Los Humeros and Cerro Prieto geothermal fields using two computer codes GeoChem (GeoSys.Chem) and WATCH is presented. GeoSys.Chem estimates the reservoir temperature and vapor fraction through quartz geothermometry and assuming enthalpy co...
Article
Full-text available
A multivariate analysis using artificial neural networks for determining the relative contribution of the cationic composition of fluids (Na, K, Mg, Ca and Li) for the estimation of downhole temperature of geothermat wells is here reported. Neural architectures were evaluated using different numerical techniques of training, activation function log...
Article
Full-text available
A comparative study of the reservoir fluid characteristics calculation of ten production wells of Los Azufres, Los Humeros and Cerro Prieto geothermal fields using two computer codes GeoChem (GeoSys.Chem) and WATCH is presented. GeoSys.Chem estimates the reservoir temperature and vapor fraction through quartz geothermometry and assuming enthalpy co...
Article
A new practical method based on rational polynomial (RP) functions to estimate the static formation temperatures (SFT) in geothermal and petroleum boreholes is described. Thermal recovery processes involved during borehole drilling and completion operations were represented by mathematical asymptotic trends. Measurements of bottom-hole temperature...
Article
Artificial neural networks (ANN) were proposed as a multivariate experimental design tool for monitoring a photo‐Fenton treatment of wastewaters containing a synthetic mixture of pesticides. ANN and Nelder‐Mead simplex methods were used to find out the optimum operating parameters of a photo‐Fenton pilot plant. ANN was developed to predict the most...
Article
Full-text available
Approximate and rigorous solutions of seven heat transfer models were statistically examined, for the first time, to estimate stabilized formation temperatures (SFT) of geothermal and petroleum boreholes. Constant linear and cylindrical heat source models were used to describe the heat flow (either conductive or conductive/convective) involved duri...
Article
Full-text available
Predicting flowing pressure and temperature profiles in geothermal wells is a fundamental task to study the in flow production mechanisms. The gas void fraction is one of the most important parameters required for the better prediction of production profiles. Eight empirical correlations (Bonnecaze, Dix model, Duns–Ros, Krilov, Hasan, Rouhani, Homo...
Article
Predicting flowing pressure and temperature proles in geothermal wells is a fundamental task to study the inflow production mechanisms. The gas void fraction is one of the most important parameters required for the better prediction of production proles. Eight empirical correlations (Bonnecaze, Dix model, Duns-Ros, Krilov, Hasan, Rouhani, Homogeneo...
Article
An artificial neural network (ANN) approach was used to develop a new predictive model for the calculation of static formation temperature (SFT) in geothermal wells. A three-layer ANN architecture was successfully trained using a geothermal borehole database, which contains “statistically normalised” SFT estimates. These estimates were inferred fro...
Article
Full-text available
tec-nológica sólida, limpia, versátil y útil para generar electricidad, entre otras múltiples aplicaciones. Debido a que sus emisiones se componen prácticamente de vapor de agua, su uso no presenta riesgo ambiental para nuestro planeta. Hoy en día, la geotermia re -presenta el 0.4 por ciento del total de la generación eléctrica mundial, aun cuando...
Conference Paper
An artificial neural network (ANN) was used to develop a new empirical correlation to estimate void fractions for modeling two-phase flows in geothermal wells. Flowing pressure, wellbore diameter, steam quality, fluid density and viscosity, and Reynolds numbers were used as input data. An explicit relationship among the input data was obtained from...
Article
Water-rock interaction experiments have provided important results in mineral dissolution studies although the steady state conditions are rarely attained. Several physicochemical factors affect the dissolution rates of minerals in laboratory experiments. Among these factors, the reaction time plays an important role when designing costly and effic...
Article
predictive model based on an application of the artificial neural networks (ANN) for obtained the flowing pressure gradients in geothermal wells was applied. The ANNmodel uses geometrical and physical data commonly measured in producing wells. The prediction of pressure gradients was successfully achieved using the following input data: wellbore ge...
Chapter
Water-rock interaction experiments have provided important results in mineral dissolution studies although the steady state conditions are rarely attained. Several physicochemical factors affect the dissolution rates of minerals in laboratory experiments. Among these factors, the reaction time plays an important role when designing costly and effic...
Chapter
A predictive model based on an application of the artificial neural networks (ANN) for obtained the flowing pressure gradients in geothermal wells was applied. The ANN model uses geometrical and physical data commonly measured in producing wells. The prediction of pressure gradients was successfully achieved using the following input data: wellbore...
Article
Full-text available
Drilling the hard–rock found in and around geothermal systems for the completion of wells is widely recognized as a difficult and costly task. Drilling fluids of high viscosity (also called muds) are required for the well drilling operations. These fluids must be analyzed for the evaluation of their rheological properties, which are crucial for tra...
Article
Full-text available
Drilling the hard-rock found in and around geothermal systems for the completion of wells is widely recognized as a difficult and costly task. Drilling fluids of high viscosity (also called muds) are required for the well drilling operations. These fluids must be analyzed for the evaluation of their rheological properties, which are crucial for tra...
Article
The freely available computer program Solute Geothermometers (SolGeo) was written and tested using geochemical data and reported geothermometric temperatures from several geothermal wells from around the world. Subsurface temperatures for the Mexican geothermal fields of Cerro Prieto, Las Tres Vírgenes, Los Azufres, and Los Humeros were estimated b...
Article
Full-text available
Three new improved equations of the Na/K geothermometer were developed through computational (artificial neural networks) and statistical tools (based on ordinary linear regression) from the analysis of a more representative world geochemical database (n=212) than hitherto used. The new Na/K geothermometers are given by the following equations: t°...
Article
Full-text available
Three new improved equations of the Na/K geothermometer were developed through computational (artifi cial neural networks) and statistical tools (based on ordinary linear regression) from the analysis of a more representative world geochemical database (n=212) than hitherto used. The new Na/K geothermometers are given by the following equations: 27...
Conference Paper
The modeling of heat and fluid flow inside two-phase geothermal wells is a vital task required for the study of the production performance. Gas void fraction is one of the crucial parameters required for a better prediction of pressure and temperature gradients in two-phase geothermal wells. This parameter affects the correct matching between simul...
Article
The biomass of the cyanobacteria, Spirulina maxima 2342, was autotrophically obtained in a 20l bioreactor under illumination and air bubbling and analyzed for its photobiological hydrogen production capability. A volume of 250ml of Spirulina sp. taken from the reactor was used as culture sample for performing the experiments. An illumination–agitat...
Article
Full-text available
High-performance liquid chromatography (HPLC) and ion chromatography (HPIC) have been widely used as cheap, relatively rapid, precise and accurate separation and quantification analytical techniques for the rare earth elements (REE). In this “Back to Basics” review, a general description of the basic components of instrumentation and the most commo...