To recycle and utilize the reaction heat in the production of furnace grade phosphoric acid and to improve the security and economy of the whole production system, a novel phosphorus reaction tower with circulating water wall was developed on the basis of the analysis of present manufacturing process and equipment, and the mechanism of high-temperature corrosion was also analyzed according to experimental tests and operating conditions. Meanwhile, the measures of the whole life cycle anti-corrosion taken to new phosphorus reaction tower were proposed, considering multiple factors including design, manufacture, and operation. The research suggested that the fins close to phosphorus burner, heat exchange tubes toward phosphorus burner and the welds between fin and tube were dangerous zones to be corroded and should be given special protection. In addition, it has been proved that 390-440 °C surface temperature of water wall, local water cooling jacket around the oblique burner, plasma-sprayed ZrO2 ceramic coating on heating surface, ultralow carbon austenitic stainless steel rich in Cr and Ni elements are beneficial to avoid the corrosion of high-temperature phosphoric acid and its polymer.
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