Dynamic model comparison of the temperature variation in a microalgae cultivation pond utilizing furnace off-gas

The mining industry has been shown to be extremely energy intensive and despite the governmental regulation and the request of local communities, it is still one of the most environmentally damaging industries in the world. These facts, coupled with a global energy crisis, climate change and a rise in the average global standard of living which results in a decrease of resources, researchers have begun searching for alternatives to fossil fuels and technology that may lead to an increase in the efficacy of existing technologies.;This thesis encompasses this ideology of new and renewable fuel sources as well as the reduction of pollution emissions and improvement of existing technologies by investigating the effect of using the process off-gas from an electric arc smelting furnace, which has a high carbon dioxide concentration and a high temperature in order to support microalgae cultivation ponds. There are several benefits from this type of technology which include the reduction of CO2 emissions from the smelter, using the waste heat for a positive purpose, the incubation of microalgae ponds which have a high lipid content which in turn could provide an oil source to produce biodiesel that can be reused on the mine site. Other benefits could include waste water treatment as some species of microalgae have been demonstrated to bioaccumulate metals as well as using the dry microalgae biomass as a fertilizer in land rehabilitation.;The first objective of this thesis was to gather a body of knowledge that incorporates or makes feasible the use of microalgae in the mining industry. Because this type of technological application is so new, there is very little comprehensive information surrounding its utilization. By creating a comprehensive literature survey, it provides future researchers with a solid beginning. The second objective of this thesis was to compare and contrast simulations that model the temperature response of microalgae incubation ponds that make use of smelter furnace off-gas. Using mathematical models, the effect of sparging high temperature off-gas from a typical smelter furnace through a pond of water in order to raise the temperature so that it would be suitable to incubate microalgae were investigated.;Three models were successfully designed and tested. They were then compared in order to determine which was the most accurate to a real-world situation. They incorporated climatic variable such as the ambient air temperature, solar insolation, wind speed and relative humidity. The climates of several geographical locations were compared in order to determine which sites were more suitable for the experimental setup. The process variables that were investigated included the off-gas temperature and flow rate that was sparged into the pond water. Investigations were also made into the effect of adding a cover to the pond, such that might be used in a greenhouse, and also the effect of insulating the pond walls and bottom.;It was determined that the best effect on pond temperature for all locations tested occurred when the pond was covered with a polypropylene cover and insulated with polyurethane sheeting on the sides and bottom with process variables at values of 50°C and 40 m3/s for off-gas temperature and flow rate respectively.