Marcos A. Coronado

Solar Energy for a Solvent Recovery Stage in a Biodiesel Production Process

Recent research and development of clean energy have become essential due to the global climate change problem, which is caused largely by fossil fuels burning. Therefore, biodiesel, a renewable and ecofriendly biofuel with less environmental impact than diesel, continues expanding worldwide. The process for biodiesel production involves a significant energy demand, specifically in the methanol recovery stage through a flash separator and a distillation column. Traditionally, the energy required for this process is supplied by fossil fuels. It represents an opportunity for the application of renewable energy. Hence, the current study presents a system of thermal energy storage modeled in TRNSYS® and supported by simulations performed in ASPEN PLUS®. The aim of this research was to supply solar energy for a methanol recovery stage in a biodiesel production process. The results highlighted that it is feasible to meet 91% of the energy demand with an array of 9 parabolic trough collectors. The array obtained from the simulation was 3 in series and 3 in parallel, with a total area of 118.8 m2. It represents an energy saving of 70 MWh per year.

Virtual Instrument for Emissions Measurement of Internal Combustion Engines.

The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user.

SWOT Analysis Applied to Wheat Straw Utilization as a Biofuel in Mexico

Wheat is one of the main crops worldwide with a production of 733 million of tons by 2015. By 2013, the wheat grain production in Mexico was 3,357,307 t. Wheat straw is generated as a biomass waste once the wheat is harvested. However, the agricultural biomass waste has acquired international relevance as a source of bioenergy. The utilization of bioenergy has significant environmental benefits, and also economic benefits because the biomass waste is valorized as biofuel. The use of wheat straw as raw material for any productive process presents diverse factors that must be consid‐ ered. Among those factors are the low density of biomass, handling and high transpor‐ tation cost, an attractive heating value, and the physicochemical characterization. Therefore, the aim of this work was to apply the SWOT analysis to wheat straw utilization as a biofuel in Mexico. The main findings highlighted an estimation of 4,612,950.23 t of wheat straw generated. The experimental results of proximate analysis were 64.42% volatile matter, 19.49% fixed carbon and 16.09% ash. The higher heating was 14.86 MJ/kg. An energy potential of 69 PJ per agricultural cycle was calculated, equivalent to 19% of the biomass energy share reported in Mexico’s National Energy Balance, by 2014.

Power generation estimation from wheat straw in Mexico

Abstract 1 Introduction Wheat is one of the foods most in demand with global consumption per capita; 56.8 kg/year in 2012/13 [1]. According to FAO [2], wheat crops worldwide were Energy and Sustainability VI 101 WIT Transactions on Ecology and The Environment, Vol 195, www.witpress.com, ISSN 1743-3541 (on-line)

Renewable Energy Integration: Economic Assessment of Solar Energy to Produce Biodiesel at Supercritical Conditions

In recent years, research on noncatalytic methods for biodiesel production has increased, mainly processes under supercritical conditions that allow the processing of waste vegetable oils (WVO) without the need to use catalysts, where the absence of catalyst simplifies the processes of purification of biodiesel. The high consumption of alcohol and energy to maintain the appropriate conditions of pressure and temperature of the reaction has turned the processes of supercritical conditions into an unfeasible method. However, the stages of biodiesel purification and methanol recovery are more straightforward, allowing the reduction of the total energy consumption by 25% compared to alkaline methods. Therefore, the present work describes a study through Aspen Plus® of the production of biodiesel by a process in supercritical conditions with WVO as raw material. Also, a solar collector arrangement was structured using the TRNSYS® simulator to supply energy to the process. To evaluate the economic feasibility of the proposed process, the installation of a pilot plant in Mexicali, Baja California, was considered. The internal rate of return (IRR) and the net present value (NPV) were determined for ten-year period. The planned system allows supplying solar energy, 69.5% of the energy required by the process, thus reducing the burning of fossil fuels and the operation cost. Despite the additional investment cost, for the solar collectors, the process manages to maintain a competitive production cost of USD 0.778/l of biodiesel. With an IRR of 31.7%, the investment is recovered before the fifth year of operation. The integration and implementation of clean technologies are vital in the development of the biofuels.

Cotton Stalks for Power Generation in Baja California, Mexico by SWOT Analysis Methodology

Baja California is a state located in the northwestern region of Mexico. From 2003 to 2013 the average cultivated area reported was 228,094 ha; 9.5% of that area was used for the cotton crop Gossypium Hirsutum variety. Cotton harvesting generates considerable amounts of cotton stalks as biomass residuals. Cotton stalks have a high energy potential currently unexploited productively, and whose disposition is open burning. This activity is performed because it reduces the costs of land preparation for the next agricultural cycle and also prevents the spread of pests and diseases in future crops. The use of agricultural biomass waste has acquired more international relevance as a source of renewable energy. The replacement of fossil fuels and mitigation of greenhouse gas emissions responsible for climate change are among the most important environmental benefits of bioenergy. Therefore, the aim of this work was to analyze the factors that would affect the development of a transformation industry of biomass into energy by strengths, weakness, opportunities and threats (SWOT) methodology. The energy potential for heat and power generation from cotton stalks was estimated. The results highlighted that from cotton stalks it is feasible to obtain an average of 1.40 PJ annually, equivalent to 39,082.67 m3 of diesel, and thus supply a power plant with 14.78 MW of installed capacity. This energy would contribute to the diversification of the energy matrix of Baja California, which currently depends on the external supply of fuels because it does not have proven reserves of petroleum resources.