Electrical energy production from waste flue gas and heat exchanger design

The development of technology and the increasing population increase the dependence on energy. Since our country is one of the energy importing countries, it is important to use energy efficiently. In this context, studies on energy efficiency need to be carried out in places where energy consumption is high. The main purpose of this study is to reveal the impact on efficiency and the environment by converting the waste flue gas produced by a business with high energy consumption into useful work within the business. In this context, analyzes were made by targeting a business operating in the metal sector located in Merzifon Organized Industrial Zone. Studies were carried out on the flue gas released into the environment from the annealing furnace within the company. Flue gas data of the annealing furnace in the company were obtained through measurements made within the company. The flow rate of the waste flue gas was measured as 28.229,1 m3/hour and the outlet temperature was measured as 122,36 °C. In the light of the data obtained, a heat exchanger was designed suitable for the chimney cross-section and then a system that would generate electricity from the flue gas temperature was designed. In the design study, the heat exchanger to be used in the chimney within the company was determined as a shell-and-tube heat exchanger. It is envisaged to use the Organic Rankine Cycle to generate electricity from the flue gas temperature in the system. Engineering Equation Solver (EES) package program, which is widely used for engineering solutions, was used in the study. In the study, separate calculations were made for R290, R245fa, R134a, R600, R1234yf and R1234ze refrigerants. Thermodynamic and economic analyzes were performed for six different fluids. As a result, it has been shown that a maximum of 42,796 kW of electrical energy can be produced as a result of the designed system. In addition, the payback period of the system is calculated as 3 years and 3 months.