Controlling of Fumed Silica Particle Size Uniform Production Process Based on Burner Fluid Dynamic Simulation

As one of the most important high-tech nanomaterials, fumed silica has been widely used in many industrial fields due to its unique properties. However, particle size uniformity is still the technical barrier in this industry after years of development. Therefore, numerical simulations are employed to optimize the process parameters of a premixed multiring high-speed jet oxyhydrogen combustion reactor, and the result is applied to actual process units used in fumed silica production. By maintaining temperature consistency between inlet 2 and inlet 1 and increasing the gas flow rates of inlet 3 and inlet 4, the HCl flow and temperature field distribution in the reactor are improved significantly. The back mixing of HCl and the blocking of particles to the combustion reactor are suppressed. Compared to the original process, the median diameter (D50) of agglomerates particles and the 45 μm sieve residue content are decreased by 6.4 μm and 19.0 mg g–1, respectively. In addition, the tensile strength of high-temperature vulcanized rubber is increased by 1–1.5 MPa. The presented simulations provide technical support for quality improvements of fumed silica and a theoretical basis for the rational design of industrial combustion reactors.