Design of a gas exchanger connected to a sulfur burning furnace with computational fluid dynamics (CFD)

The thesis study focuses on designing a gas heat exchanger connected to a sulfur combustion furnace for use in the combustion process, the first step in the sodium metabisulfite production plant. Within this scope, the optimal design, computational fluid dynamics (CFD) analysis, fabrication, and mechanical calculations of the shell-and-tube heat exchanger will be discussed in accordance with the pressure vessel standard EN13445. The design uses data from a combustion furnace and gas heat exchanger from a sodium metabisulfite plant. Sulfur is one of the two raw materials used to produce sodium metabisulfite, an inorganic salt used in many industries, including cosmetics, paper, textiles, sugar, leather, rubber, canning, and mining. The food industry is the largest consumer of sodium metabisulfite. In the sulfur combustion process, sulfur burns to produce sulfur dioxide gas. (S + O₂ = SO₂) The sulfur combustion process is an exothermic reaction. The energy generated by exothermic combustion increases the temperature of the combustion gases. The desired temperature inside the furnace is between 1000 and 1200°C. At these high temperatures, the sulfur dioxide gas travels through a jacketed section connected to cooling air in the furnace. It then enters the gas heat exchanger, which is connected to the sulfur combustion furnace. The gas enters the heat exchanger at a temperature of approximately 1000°C, where it is cooled. The goal is to reduce the gas temperature to below 350°C for the next process. Designing the gas exchanger to cool sulfur dioxide gas at these high temperatures is critical. This gas exchanger is very similar to a waste heat recovery system. This study investigated the potential for recovering heat released during the gas combustion process at this chemical plant. The plan also includes the energy that can be gained by cooling the gas heat coming out of a sulfur combustion furnace operating at temperatures between 1000 and 1200°C. The inclusion of a gas heat exchanger in the sulfur combustion system aims to cool the sulfur gas temperature to a level suitable for the next process while meeting the facility's steam, heating, hot water, and process needs. This design was supported by both fluid dynamics (CFD) analysis and mechanical analysis (pressure vessel design calculation in accordance with current standards).