**Acknowledgements**

heat exchanger network of the cement plant (**Figure 8**) has illustrated the ways to use waste heat. The potential of waste heat may be used for power generation by heat engines' application as demonstrated by Quoilin and Lemort [32]. The heat duty of waste gas is 14,338 kW and the temperature is 200°C or higher (see **Figure 8**). However, if the plant is operated in the mode without a raw mill, the power generation increases as well. Important points that have to be additionally discussed are the fluctuations of plant operation parameters, solid–

Another option of waste heat utilization from integrated cement production is the covering of site heating demands. The district heating system may be potentially supplied by waste heat to fulfill energy demands. The maximum capacity of waste heat that may be used is 14,338 kW as illustrated earlier. However, the technical implementation, including the heat losses and pressure drops, has to be additionally analyzed in details along with the economic issues of the retrofit design as well as energy planning. The results presented in this chapter have a cross-disciplinary impact and additional potential for future development of new cement manufacturing processes. A new design of a heat exchanger network could be a part of an energy-efficient environmentally friendly cement manufacturing process. It reduces fos-

emission and operation cost of cement factories.

The utilization of low-grade heat for district heating systems could help for planning energy systems. The cement manufacturing process may be also considered as an energy source of district heating systems, additional power generation and so on. Nevertheless, the locations of cement factories have to be additionally analyzed with use of other systematic techniques, for example, based on total site analysis [33] to find a solution really close

This chapter provides results of research, which identified large energy-saving potential in the cement manufacturing process. Main results may be achieved by improvement of heat recovery, and potential of utility reduction is 30% and 29% for heating and cooling capacity, respectively, which translates to lower primary energy sources. These results were achieved by an updated process integration technique and update of a heat exchanger network. The case study of a particular cement factory was considered and feasible solutions were described that require an investment cost of 256,079 EUR with a payback period of 3.4 months. Besides, the improvement of energy efficiency may be additionally reached by improving the existing process of heat transfer equipment. Low-potential heat utilization covering 43% of power demands of the factory during summer operation mode and utilization of 20,225 kW of waste

The use of excess heat may provide a way to reduce the primary energy sources and contribute to

tions and most feasible solutions for a new concept design of the cement industry. Nevertheless,

the technical issues have to be additionally discussed for successful implementation.

mitigation. This chapter shows a pathway for energy efficiency, main process restric-

heat to site-district heating during winter operation are determined.

gas source streams and installation features of power generator.

sil fuel consumption, CO2

to the optimum.

108 Cement Based Materials

**5. Conclusion**

global CO2

This work was supported by the EC and Croatian Ministry of Science Education and Sports project "CARBEN" (NEWFELPRO Grant Agreement No. 39). The author acknowledges Holcim Company for provided data and personally Zoran Mohorovic for help in data extraction and reconciliation. The author acknowledges a SDEWES Centre and the Department of Energy, Power Engineering and Environment, Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, for administrative support.
