Bachelor’s Thesis

Design of a Gasification Plant with Cogeneration for the Energy Use of Rice Husks from an Industrial Process

OBJECTIVES

The main objective of this project is to study the feasibility of a high-efficiency cogeneration plant using solid biomass from rice husks through gasification. The fuel is therefore a waste product and will not be used for other energy purposes.

The aim is, on the one hand, to generate electricity with a fully renewable fuel and, on the other hand, to make use of the resulting heat, with the consequent saving of primary energy and improvement of energy efficiency.

However, it is also intended to be designed for an industrial installation in full activity today, so that the project is intended to be perfectly applicable to reality and to be viable in its practical implementation, both in technical and economic terms. The project is developed for a defined and specific installation, which does not prevent it from being developed in any other industry in the sector under similar conditions to those proposed here.

For the aforementioned reason of trying to be viable in economic terms, the project contemplates the study of the remuneration that corresponds to it within the system established for generation under the Special Regime, a regime in which it has a double place, both for the use of biomass as fuel and for the use of waste heat in cogeneration.
Having established the basic premises for action in the generation of electricity with renewable fuel and the use of waste heat, it should be noted that this project also aims to do so in a highly efficient manner, in such a way that a cogeneration plant is designed with highly efficient biomass and excellent performance from the point of view of remuneration, the latter being of great importance if its practical viability is to be achieved.

In terms of efficiency and remuneration, extraordinarily high levels are achieved, far above the usual values. Thus, for example, the overall efficiency of the installation is clearly above 50%, and in terms of remuneration within the Special Regime, the limits for an installed capacity of more than 1 MWe will be exceeded, which translates into truly high profitability figures.

This is due to the very high levels of heat utilisation, which are achieved by the methods and procedures detailed in the project, and which are possible thanks to the particular conditions of thermal demand in industry, which is very “generous” in this respect. Likewise, electricity generation is done with very high efficiency, which is achieved, firstly, through the use of gasification technology and, secondly, through the use of high-efficiency internal combustion engines running on synthesis gas.