Temporal Temperature Evolution during the Pyrolysis of Cotton Stalks, Corn Stalk and Rice Husk Using Multifunction Family Oven for the Biochar Production

Abstract

The multifunctional family oven is an oven able to produce simultaneously biochar for soil improvement and energy for cooking. However, the quality of the biochar produced depends not only on the selected biomass but especially on the pyrolysis temperature which is a very important parameter. This experimental study aims to understand the functioning of the oven with respect to its biochar production and the pyrolysis duration. To carry out our study, K-type thermocouples were used to measure the temperature on the different walls and chambers of the oven. Cotton stalks, corn stalks and rice husk were used for this study. The results obtained showed that the cotton stalks reached the maximum pyrolysis temperature at 430 °C around 1700 s. This temperature remained constant for 1500 s before decreasing to mark the end of pyrolysis. As for the corn husks, they reached their maximum average pyrolysis temperature at 470 °C after 3000 s. The rice husk reached a maximum pyrolysis temperature of 420 °C after 3500 s. A comparative study of the temperature curves of the three biomasses revealed that cotton stalks pyrolyze faster with short time than the other two biomasses. The results obtained on the pyrolysis temperature, corroborate those of the literature from which the multifunctional family oven produces a quality biochar. The maximum temperature of combustion which starts the pyrolysis is about 800 °C and can last for 1h30 min. Thus, this heat is valued by the cooking of different dishes of the country.