Techno-economic assessment of thermoelectric waste heat recovery in cement plants based on an industrially validated approach
摘要
Industrial waste heat recovery is a key strategy for improving energy efficiency and reducing carbon emissions in energy-intensive sectors such as the cement industry. Conventional technologies, including steam and organic Rankine cycles, are often limited to large-scale and centralized heat sources, leaving distributed medium-temperature waste heat streams largely unexploited. Thermoelectric generators (TEGs) provide a solid-state, scalable option that can be deployed on distributed heat sources. In this study, an industrially validated thermoelectric waste heat recovery approach is adapted and evaluated for cement plant applications. Typical waste heat sources in cement production, such as preheater exhaust ducts and clinker cooler outlets, are analyzed in terms of temperature levels and integration potential. A commercially available high-temperature TEG module is selected based on realistic operating constraints, and its performance is assessed under representative cement plant conditions for different cooling scenarios. Results show that cooling strategy and achievable temperature difference strongly influence thermoelectric performance. Under favorable conditions, area-normalized power densities of approximately 3.9–5.5 kW m−2 can be obtained for the assessed cement plant scenarios. When experimentally observed field-related losses of approximately 14% are considered to represent installation- and auxiliary-power-related effects, the corresponding net power densities are estimated to be on the order of 3.3–4.7 kW m−2, which remains consistent with values reported in industrial reference studies. These findings indicate that thermoelectric waste heat recovery can be a technically feasible and potentially attractive option for selected cement plant applications where continuous operation and high heat fluxes are available.