Some designs of direct trichlorosilane synthesis reactors: (a) multistage trichlorosilane synthesis reactor: silicon particles are fluidized in several interconnected zones that may have different composition ratios of reaction gas and supplied raw material (Pat. US 8778292, 2014); (b) two reactors (1 and 2) work in parallel: silicon particles can be directed from the first reactor to the second one; reactor 1 has selective separator 3 for Si particles (Pat. DE 102009037155, 2010); (c) reactor 1 has water cooled piping and operates at 0.5 MPa pressure; the fluidized bed temperature is maintained accurate to 1 °C; silicon supply rate to the fluidized bed is maintained accurate to 5% (Pat. US 20110297884, 2011).