This paper deals with the problem of helium ash removal from stellarator-reactor. The lower hybrid (LH) heating of ash ions is proposed to solve this problem. The theory of ion stochastic heating, developed earlier by Karney, is generalized in the case of heating in stellarators. The features of the LH waves propagation and the ions motion in the stellarator confining field are taken into account. With a proper choice of wave parameters (such as frequency, antenna position and initial spectrum of longitudinal refractive index) the slow mode of LH waves penetrates from the launching system to the plasma core (and back) without conversion to kinetic plasma mode or to fast mode. With all this going on, the LH wave is absorbed by alpha particles only. The electron Landau damping is negligibly small, and there is no bulk ions stochastic heating. The motion of high-energy (>100 keV) ions in the LHD heliotron with inwardly shifted magnetic axis, as an example of stellarator type device, is calculated numerically using the single particle simulation code which couples modified Karney's ion stochastic heating theory. The effect of collisions was taken into account through the Monte Carlo equivalent of the Lorentz collision operator. It is shown, that due to interaction with LH wave, initially well-confined alpha particles are expelled from the plasma volume during the time period which is shorter than the collision time. At the same time, the low hybrid heating does not remove the ions having an energy higher than 500 keV. Therefore, it is possible to use this method of RF heating for helium ash removal in stellarator-reactor. The required LH power is estimated to be of the order of 10 MW.