Particle charge back discharge

Back corona is caused by the electrical breakdown of gas in the dust layer. This breakdown produces positive ions, which drift toward the negative discharge electrode. The presence of ions with opposite polarity causes a reduction in the particle-charge and -collection efficiency. To avoid this problem, several methods are used. These include... 

Thus, the chlorination of titanium raw stock in salt melt helps to build very productive apparatuses and avoid labour-intensive operations of preparing and backing bricks, partially increases the conditions for further condensation of the vapour and gas mixture, considerably reduces the concentration of carbon oxide in outlet gases and helps to withdraw the non-chlorinated residue from the reactive zone continuously. Disadvantages of chlorination in salt melt include increased losses of titanium with discharge melt (because small particles of the furnace charge are carried away with reaction gases) and increased amounts of solid chlorides. 

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