Waste Heat Recovery to Improve the Carbon Footprint a Case Study: Cement Industry in Jordan

The energy efficiency of the cement production process is considered relatively low due to heat losses from thermal radiation. This work aims to recover waste heat in a cement factory. It is used in preheating the clicker and hence cut down the petroleum coke used to heat it and consequently cut down the carbon footprint that is emitted during the burning process of petroleum coke. This objective is achieved by designing, testing, and validating a waste heat recovery system using the Finite Element Methods software program ANSYS. This heat recovery system comprises the oven tube, the parabolic trough collector with an absorber pipe, through which working fluid is heated up, and a heat exchanger that is used to preheat the clinker flowing inside the oven. The simulation work has involved estimating the temperature distribution of the surface of the absorber pipe, the temperature distribution of the working fluid flowing through this pipe, the oven outside surface temperature, and the one of the surface of the reflector. In addition, this work has involved the calculation of recovered heat by the system, the mass flow rate of the working fluid within the absorber pipe, the consumption rate of petroleum coke, and the amount of carbon footprint during the burning of fuel that is caused as the consumption rate of the power is reduced. It has been found out that the amount of heat recovered by the system may reach 340.12 kW per hour. This leads to a reduction in the petroleum coke used in the factory to 22005 tons per year and hence an annual decrease in the amount of carbon footprint to 68905 ton CO2.