This paper describes an investigation of an electromagnetic separation approach for separating inclusions in molten aluminum. The separation is effected by a magnetic field generated by a direct current, resulting in a Lorentz force. On the basis of this magnetic separation method, we constructed a sensor probe and rigorously analyzed it from a mathematical point of view. Specifically, we calculated the magnetic field inside the probe and showed that a nonuniform body force density is established throughout the melt volume, resulting in a decrease in probe efficiency. Moreover, we analyzed the rotational motion of the melt under the influence of the spatially dependent body force, and reasoned that this rotational motion also adversely affects the probe performance. To overcome these two drawbacks, we propose a new probe design. The goal of the new design is to increase strength and uniformity of the body force distribution within the aluminum melt.