Processing of rice huskss and obtaining a ceramic composite based on it

Introduction. Every year, the demand for rice around the world is steadily increasing, leading to an expansion of its cultivation and production. However, this increase in production also leads to the generation of large amounts of waste, particularly rice huskss. The introduction provides a literature review of the processing and use of rice huskss for various purposes. When producing 1 ton of polished rice, about 200 kg of rice huskss is formed, from which approximately 40 kg of ash remains after burning. Methods and materials. As a result of the research it was established that the main components of rice huskss are: cellulose (40-45%), lignin (about 20–25%) and hemicellulose (about 15%). The rest of the composition depends on the deposit and variety of rice. Processing rice huskss using hydrocavitation and pyrolysis units opens up new possibilities for producing ceramic composites. A spectral analysis of the chemical composition of rice husks from the Suzak district was carried out. The results of the analysis showed that the main component of the solid mass of rice husks is SiO2 – 400 mg/kg, MnO – 195 mg/kg, K2O – 120 mg/kg, MgO – 30 mg/kg, CaO – 20 mg/kg, P – 13 mg/kg, Na2O – 3.9 mg/kg, Fe2O3 – 3 mg/kg, Ag – 0.04 mg/kg, and other impurities. The article presents a methodology for studying the composition and properties of rice huskss components. A flow chart for the process of fast pyrolysis of rice husks is presented. The preliminary chemical composition of bentonite from the Tegerek deposit was determined by the spectral method as part of the development of a ceramic composite. Main components: SiO₂ – 50%, Al₂O₃ – 12%, Fe₂O₃ – 12%, MgO – 4%, CaO – 3%, K₂O – 2%; other elements are present as minor impurities. Results. The experimental part used hydrodynamic cavitation technology, as a result of which rice huskss was processed using a hydrocavitator. Results: It was found that after cavitation treatment, rice husks is divided into three fractions: coarse mass – 75%, plastic mass – 15.83%, and a fine fraction, constituting 9.6%, suspended in water. The composition, structure and physical and technical characteristics of the coarse and plastic fractions of rice husks were studied. Rapid pyrolysis of the coarse fraction after cavitation treatment was carried out. Based on the resulting ash and silicon-carbon material formed during the pyrolysis process, dense and porous ceramics for various purposes were synthesized. Conclusion. A technology for processing rice huskss using the created hydrocavitator and the method of fast pyrolysis for obtaining a ceramic composite has been developed. A study has been conducted of the composition and structure of rice huskss after cavitation treatment, as well as solid residues formed as a result of fast pyrolysis. As a result, both dense (ρ = 1.19–1.22 g/cm³) and porous (ρ = 0.51–1.02 g/m³) ceramic composites based on processed rice husks were obtained using hydrocavitation and pyrolysis.