Flowsheets sulfur burning

Fig. 1.4. Double contact sulfuric acid manufacture flowsheet. The three main S02 sources are at the top. Sulfur burning is by far the biggest source. The acid product leaves from two H2SO4 making towers at the bottom. Barren tail gas leaves the final H2S04 making tower, right arrow.

Fig. 3.1. Sulfur burning flowsheet - molten sulfur to clean dry 700 K S02, 02, N2 gas. The furnace is supplied with excess air to provide the 02 needed for subsequent catalytic oxidation of S02, to SO3. Table 3.1 gives industrial sulfur burning data.

Fig. 21.1. Heat transfer flowsheet for single contact, sulfur burning sulfuric acid plant. It is simpler than industrial plants, which nearly always have 4 catalyst beds rather than 3. The gaseous product is cool, S03 rich gas, ready for H2S04 making. The heat transfer product is superheated steam. All calculations in this chapter are based on this figure s feed gas composition and catalyst bed input gas temperatures. All bed pressures are 1.2 bar. The catalyst bed output gas temperatures are the intercept temperatures calculated in Sections 12.2, 15.2 and 16.3.

Fig. 23.1. Simplified single contact sulfuric acid production flowsheet. Its inputs are moist feed gas and water. Its outputs are 98 mass% H2S04, 2 mass% H20 sulfuric acid and dilute S02, 02, N2 gas. The acid output combines gas dehydration tower acid, H2S04 making tower acid and liquid water. The equivalent sulfur burning acid plant sends moist air (rather than moist feed gas) to dehydration. Appendix V gives an example sulfur burning calculation.

In contrast with the conventional contact sulfuric acid that operates with dry sulfur dioxide/air mixtures, wet gas is used in the wet contact process 113). The hydrogen sulfide in the initial gas is first burned to SO2 and HgO. The sulfur dioxide is then converted to SO3, which combined with the steam that is formed fields sulfuric acid. The process flowsheet is given in Rgure 11.9. 

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