Desenvolvimento e construção de um queimador de biomassa automatizado com microcontrolador

Abstract

Biomass pellets are cylindrical and standardized pressed solids from industrial waste or agro-industrial by-products and, due to their low cost, stand out between wood and diesel oil. Biomass pellets are gradually replacing fossil fuels in the generation of renewable energy, with the use of compact equipment and the reduction of the pollutants released in their combustion. The raw materials for making the biomass need to have cellulose, hemicellulose and lignin, being also important calorific value, fixed carbon and ash content.In small equipments, continuous supply, combustion temperature, humidity, calorific value and primary and secondary air supply are related to incomplete combustion and emissions of air pollutants.For a complete firing it is necessary to have a homogeneous arrangement of gas flow and temperature, an adequate air/fuel ratio, avoiding oxygen deficiencies, low temperature, mixing insufficient and short time of the gases in the combustion chamber. The study presented in this project covers small pellet burners that are used to generate heat in the heating of air and in the generation of hot water or steam in heat exchangers, being the development of the prototype of the burner being directed by the objectives exploring the considerations and the improvements to the problems to be improved as gradual automatic fuel feed, a suitable place for the introduction of primary and secondary air, provision of a control mechanism to regulate excess air, maintaining the combustion gases for as long as is necessary for complete burning and foreseeing ash displacement. The project development also aims to reduce fuel waste, carbon monoxide (CO), nitrogen oxide (NOx), sulfuric acid (SO2), and ash emissions; maintain an appropriate combustion temperature, to improve heat generation and cool critical points that influence service life.