Development of briquettes suitable for energy generation from residue of sorghum stalk and groundnut husk

Abstract

Fossil fuels dominate the world's energy consumption, including transportation, chemicals, and materials generation. Conversely, using conventional energies has resulted in massive environmental damage and climate change. This study looks into developing briquettes from sorghum stalks and groundnut husks utilizing cow dung as a binder for fuel production using the low-pressure compaction method, an important renewable energy source. The briquettes were labeled with cow dung binder compositions (5–25%), ratios (75–95%), and particle sizes ranging from 1 to 3 mm. The raw materials were collected and cleaned, then sun-dried, followed by carbonized and ground using a mortar grinder. Design of Expert (DOE) software, Excel, and analysis of variance (ANOVA) were used to perform numerical and graphical data analyses. After briquetting, the proximate properties of the moisture content were 3.16%, fixed carbon 13.04%, volatile matter 80.20%, and ash 3.6%. The briquette had 51.56% carbon, 6.302% hydrogen, 0.0042% nitrogen, 42.134% oxygen, and 0.00093% sulfur. The calorific value of mixed briquettes varies from 20.08 to 24.36 MJ/kg. The maximum calorific value was achieved with a particle size of 1 mm and a 25% cow dung binder content, as a minimal particle size was preferred. According to the analysis, the created briquettes were smokeless, low in Ash content, and had a high Calorific value for burning above 17 MJ/kg for industrial driving and above 13 MJ/kg for household usage. The result of standardization on the diet of cow dung revealed that grain-fed dung offered a higher calorific value of 20 MJ/kg, while a higher shatter resistance of 90% was recorded using grass straw fed, which outlines the importance of diet on the efficiency of the binder. Developing briquettes from these biomasses can increase job prospects, decrease greenhouse gas emissions, and improve waste management.

Graphical Abstract