Investigation of the Pulsed Annular Gas Jet for Chemical Reactor Cleaning

The most economical technology for production of titanium dioxide pigment is plasma-chemical syntheses with the heating of the oxygen. The highlight of the given reaction is formation of a solid phase as a result of interactions between two gases, thus brings the formation of particle deposits on the reactor walls, and to disturbing the normal operation of the technological process. For the solving of the task of reactor internal walls cleaning the pulsed gaseous system was suggested and investigated, which throws circular oxygen jet along surfaces through regular intervals. Study of aerodynamic efficiency of the impulse system was carried by numerical modeling and experimentally with the help of a specially created experimental facility. The distribution of the pulsed flow velocity at the exit of cylindrical reactor was measured. The experimental results have shown that used impulse device creates a pulsed jet with high value of the specified flow rate. It allows to get high velocities that are sufficient for the particle deposits destruction and their removal away. Designed pulsed peelings system has shown high efficiency and reliability in functioning that allows us to recommend it for wide spreading in chemical industry. 1. Introduction The most technologically advanced and economical method of production of titanium dioxide pigment is a plasma-chemical synthesis of oxygen with heating to 3500？K in an arc plasma torch [1–3]. In this process, titanium dioxide is formed by the oxidation of atomized liquid titanium tetrachloride, which interacts with an oxygen plasma. Chemical reactor, which implements the technology in question, represents a cylindrical tube with an inner diameter of 200–300？mm and a length of 1,000–2,000？mm. At the entrance to the reactor, a torch is installed, which creates a high subsonic jet of oxygen and feeder tetrachloride into the jet. At the reactor outlet, gas stream is obtained with particles of titanium dioxide, which are separated in a certain way from the gas phase. A feature of this reaction is the formation of a solid phase as a result of the interaction of two gaseous components. Originally appearing particles of titanium dioxide are in gaseous state, then the condensation of the molecular-dispersed titanium dioxide formed aerosols. As the particles pass the reactor space as their size increases due to condensation of titanium dioxide from the gas phase on the particle surface and by coalescence of individual particles into larger agglomerates, resulting in particle sizes reach 0.1–0.4？microns. This raises the problem