Diseño de un biorreactor para la producción biotecnológica de ácido itacónico

Abstract

In recent years, the European Union has been responsible of encouraging policies that favor the implementation and development of processes that offer a real and competitive alternative to the use of fossil fuels. For this reason, in the last years, the study and optimization of processes that synthesize competent substitutes of non-renewable raw materials has acquired great importance in the industry and the market and, therefore, in the Chemical engineering sector. One of the compounds with more potential to become the alternative to petroleum-based plastics is itaconic acid. Despite the great advantages of using itaconic acid as Building Blocks, the current use could be considered limited due to the high cost of the production route. Based on this, it has been decided to make the main objective of this EDW the design of a bioreactor for the biotechnological production of itaconic acid from a waste effluent from the sugar industry. These residues are concentrated in sugarcane molasses, which is considered a high quality raw material because of its high glucose content. Due to the fact that this topic is considered an innovative one and there are few studies in the literature about the continuous production of itaconic acid from sugarcane molasses (most of them are focus on obtaining IA from glucose in discontinuous processes), it has been decided to design and size a bioreactor of this nature with the object of expanding and improving the knowledge of the bioprocess. First of all, a feasibility study is carried out analyzing the current market of IA and the short-medium-term forecasts of the worldwide consumption of our product. Once it is established that our product is considered interesting for the market, a bibliographic study about cultivation methods used until the moment and the state of the art is carried out. It is also necessary to fix the raw materials, the nutrients, the microorganism and the optimal process variables through the bibliography. Secondly, the bioreactor design is begun. The production is based on a process not associated with biomass growth so a very important factor to take into account is that the microorganism will be introduced by resting cells to provide the maximum production of AI. The process is carried out at 35 ° C because of the microorganism, A. terreus, is a mesophilic microorganism. This facilitates to decrease of the consumption of energy due to the fact that we are dealing with a temperature near to atmospheric temperature. Then, it is necessary to design the agitation system considering that it is an aerobic process and, therefore, the optimum oxygen concentration for the process is approximately 0.41 L O2/L·min. Seeing as the project works with cells, the agitator complexity increases because it is necessary to control the hydrodynamic stress that the microorganism can suffer. Although the object of the present EDW is the design of a bioreactor, the auxiliary equipment that forms part of the fermentation step is also introduced as the object of study. The auxiliary equipment studied here is: the pump that allows the input of the raw material in the bioreactor and the compressor that provides the aeration. To ensure the safety and efficiency of what was previously designed is inserted a safety study of variables that can alter the process results with the HAZOP analysis. Once the controlled variables are set, the instrumentation and control of the process is designed through the P&ID diagram that represents how to indicate, transmit and control the variables that must be constant. In order to confirm that the project complies with current regulations and also that it is a responsible project with the environment, a simplified environmental impact study is carried out. In this study, it is verified that on the one hand our project does not exert any negative representative effect and on the other hand the socio-economical and socio-cultural factors have been enriched the industry area. Finally, budgets are made in order to obtain the general execution budget of our project which includes the cost of the equipment of the fermentation stage, as well as the general expenses and the industrial benefit of the process in addition to the value added tax. As a conclusion, it can be established that the production of compounds that are able to replace fossil fuels through the use of biotechnology is increasing its viability. This occurs because the study of different routes allows to increase the efficiency of the equipment used, as well as to optimize the processes thus reducing the cost of the process. Also, the reuse of waste from other industries to obtain these compounds is optimal, reducing the consumption of raw materials and also the amount of waste generated.