I've been recently thinking about black holes and...,

...let's say we have a black hole that doesn't radiate anything. Then you will drop this black hole to some solid surface (let's say the black hole has relatively small mass -> $0{,}5$ $\mathrm{kg}$, which implicates very big density and let's also say that this surface is Earth surface). We know that anything below Schwarzschild radius ($R\_s=2G\_EM\_d/c^2$) cannot escape from the black hole. And here's my question: How can I compute how many of surrounding matter can black hole swallow in some given amount of time (for example 3 hours or 2 days)? Or how long does it take for the black hole to swallow $2$ $\mathrm{kg}$ of matter.

Thanks a lot!

Edit: In reaction to the first comment...I would abandon any geothermal and thermodynamical processes. You're currently at Earth's surface and black hole you just made, you recently dropped. Gravitional field is heading towards the geometric center of Earth and that is where the hole is heading (free fall?). Earth has almost none density compared to our black hole, so that black hole will fly threw it like nothing, yet cannot leave Earth because of gravity. That way it will be oscillating. I want just a model of how this could be computed (amount of time in which the black hole can swallow a particular amount of matter). Let's assume ideal conditions.