Freeze separation of saline oil sands mine waste water

This study investigated the feasibility of trickle freeze separation as an alternative treatment method for saline oil sands mine waste water. Using a specially designed flume housed in a cold room, several experiments were conducted at various ambient temperatures, salt concentrations and mass flow rates. The experiments showed the production of slush and subsequent erosion hindered the trickle freeze separation process. Melting actually proved to be more effective at concentrating salts than the freezing process. More than 80% of the salts could be concentrated during melting into less than one third of the original volume. Utilizing results from the laboratory scale experiments, a pulse-trickle freeze separation system was designed for 20 million m³/year of saline oil sands process water. The capital investment for construction of the pulse-trickle freezing system was $127 million or $6.36/m³ capacity. Yearly operating costs amounted to $0.13/m³ of waste water.