Evaluation de l’efficacité des gazéificateurs et coques de riz comme source d’énergie et évaluation de la toxicité des fumées chez les rats

Abstract

This study was conducted to ensure the efficient use of rice by-products and to increase the productivity of the rice value chain. Different types of briquettes were produced by varying four parameters namely: The Husk: Bran ratio (1: 1, 1: 2, 1: 0, 0: 1, 2: 1), the drying method (MS) (sun and oven), the particle size (fine, medium, large) and the water temperature (97 ° C for boiled water, 28 ° C for water at room temperature) to determine the combination that would produce an optimal performance of briquettes. The Controlled Cooking Test (CCT) and the Water Boiling Test (WBT) protocols were used for benchmarking the performance of stoves using the briquettes produced in this study to other gasification stoves using pure rice husks (R: Rua; VRHS: Viet; PO150: Paul Olivier 150; PO250: Paul Olivier 250 and M: Mayon) and traditional fuels. A Life Cycle Assessment (LCA) of rice husk gasifiers was evaluated by simulation using SimaPro software, and evaluation of in vivo toxicity of rice husks was carried out in Wistar rats. The results showed that the use of binders or other forms of binders was necessary to produce rice husk briquettes of sufficient hardness. The husk–bran–palm press fiber (HBF) and husk–bran only (HBO) briquettes showed the best fuel quality in terms of hardness, ease of ignition, heat value, ash content, burning rate, specific fuel consumption, and flame temperature compared to briquettes husk–bran–palm press sludge (HBS) and husk–biochar–clay (HBC). The fan-assisted gasifiers (R, V, and PO) had better thermal indices compared to naturally ventilated M and traditional fuel-burning fireplaces. For the sub-chronic toxicity study, boiled water at doses of 0.5, 1, and 2 ml/100 g showed significant differences (p≤ 0.05) in some parameters such as creatinine in males (71.81 mg/dL), uric acid (2.75 mg/dL) and total bilirubin (0.08 mg/dL), and granulocytes (2.70 103/µL) in females compared to Control group (64.16 mg/dL, 2.25 mg/dL, 0.19 mg/L, and 1.80 103/µL for each parameter respectively), but data were below the threshold levels to be considered to have toxic effects. In conclusion, these results on rice husks used as fuel were obtained in order to increase confidence in its safety for humans when used in household cooking.