Energy audit and Design of Heat recovery system in preheater of Messebo Cement Factory

Abstract

The cement industry is one of the most energy-intensive sectors, accounting for a significant share of global fuel and electricity consumption. Energy costs typically represent 30–40% of the total production cost of cement, making energy efficiency a critical factor for competitiveness and sustainability. This study presents a comprehensive **energy audit and waste heat recovery (WHR) system design** for a cement manufacturing plant, with the objective of identifying energy-saving opportunities, optimizing thermal and electrical consumption, and reducing overall operating costs. The **energy audit** was conducted to evaluate energy flows within major plant sections, including the raw mill, preheater, kiln, clinker cooler, and cement mill. The audit identified considerable waste heat losses, particularly from the **preheater exhaust gases** and **clinker cooler hot air**, which together account for more than 25–30% of total thermal energy input. The technical assessment shows that the designed WHR system has the potential to generate up to **4MW of electricity**. This reduces dependency on the national grid and lowers production costs. In conclusion, the integration of a WHR system in the cement plant not only improves **energy efficiency and cost competitiveness**, but also aligns with global sustainability goals and national energy policies. The study strongly recommends implementation, supported by the demonstrated technical feasibility, economic viability, and environmental benefits.