Work

A technical assessment of thermoelectric generator integration for waste heat recovery in air preheaters and effluent reactor pipelines of the carbon black industry

Year: 2026

Type: article

Abstract: Carbon black production is widely recognised as an energy-intensive industrial activity with a substantial environmental footprint. A major challenge in its manufacture lies in the significant thermal energy losses associated with continuous high-temperature processes, spanning both high and medium temperature ranges, which reduce overall energy efficiency while increasing gaseous emissions. This study evaluates the feasibility of reducing these losses through the integration of thermoelectric generators (TEGs) for waste heat recovery in two representative units of the carbon black production process. The first is an air-to-air heat exchanger (APH) in the pelletizing section, operating at temperatures around 500 °C. The second is a reactor effluent duct located downstream of the reactor, where the process gas must be cooled to meet downstream operational and safety requirements, with temperatures decreasing from 700 °C to 300 °C. The analysis is based on real operating data and employs commercially available Bi₂Te₃-based thermoelectric modules operated within their allowable temperature limits. A one-dimensional thermo-resistive model is developed to describe heat transfer across the process gas, refractory lining, thermoelectric modules, and cooling system. A systematic sensitivity and optimization analysis is performed to assess the influence of refractory properties, thickness, and cooling strategies—including natural convection and forced convection with air and water—under realistic industrial constraints. All proposed cooling configurations rely exclusively on existing plant utilities and require minimal modifications to the current infrastructure. It is demonstrated that electrical power can be generated using TEGs with appropriate thermal configurations. The main limitation is gas-side convection, making thermal design crucial. Overall, the carbon black process is shown to be a viable environment for TEG application under medium- and high-temperature industrial conditions.

Source: International Journal of Heat and Mass Transfer

DOI: 10.1016/j.ijheatmasstransfer.2026.129132

Authors: Mónica Miguélez-García, Pablo Fernández-Yáñez

Institution: University of Castilla-La Mancha

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDGs: Responsible consumption and production, Affordable and clean energy, Industry, innovation and infrastructure, Climate action

Open Access status: hybrid

Estimated APC paid: $4,220