Divergence problem in black hole brick wall model

In this work we review, in the framework of the so-called brick-wall model, the divergence problem arising in the one-loop calculations of various thermodynamical quantities, such as entropy, internal energy, and heat capacity. Particularly we find that, if one imposes that entanglement entropy is equal to the Bekenstein-Hawking one, the model gives problematic results. Then a proposal of a solution to the divergence problem is made following the zeroth law of black hole mechanics.