Smelter off-gas waste heat and carbon dioxide sequestration to promote production of biodiesel

CIM Journal Preprint, Vol. 8, No. 3, 2017

C. A. Laamanen and H. Shang
Bharti School of Engineering, Laurentian University

G. M. Ross
Northern Ontario School of Medicine

J. A. Scott
Bharti School of Engineering, Laurentian University

The indirect recovery and use of waste heat contained in smelter off-gas is proposed as a means to significantly expand the regions available for year-round on-site production of microalgae sourced biodiesel, a fuel that could be beneficially used in underground machinery. A dynamic model of an off-gas heat exchanger was developed that describes both the capture and the even distribution of heat into open, externally located rectangular microalgae ponds. In the example used, smelter off-gas is shown to contain sufficient energy to maintain large-scale microalgae cultivation pond temperatures above 15°C, even with winter ambient temperatures below –15°C. The results highlight opportunities that could lie in tapping these types of heat resources to help produce renewable biofuels on-site and sequester carbon dioxide, whilst leaving the industrial process unaffected.

Keywords: Biodiesel, Clean burning, Heat recovery, Microalgae, Modeling, Off-gas, Smelters