The paper presents an adaptive air stream control algorithm for use in a bioreactor for waste composting. The system controls the streams of air supplied to the six ducts of the bireactor. Bioreactors of this type are characterized by the fact that the porosity of the charge is very heterogeneous throughout the volume. In addition, during the process, the charge is compacted and blockages for the gas flow often occur. The control algorithm should take into account the formation of blockages and attempt to clear them. In situations where unblocking is impossible, it should ensure proper distribution of air flow in other ducts despite the presence of blockages. The overriding goal of this algorithm is to ensure equal air flow streams in all channels, regardless of differences in flow resistance. Since the air circulation in bioreactors is forced by fans with constant capacity, the algorithm should adaptively determine the maximum average value of air streams that is possible to obtain under given conditions and adjust the control system to achieve it. The paper proposes a solution to meet these requirements.