A foreign object removal system is disclosed including a removal chamber projecting laterally from the combustion chamber of a fluid bed reactor and connected via a downwardly directed pipe to a material flow control plenum chamber, which includes means for fluidizing the mixture of inert bed particles and foreign objects at the bottom of the pipe for lateral movement into an air classifier, wherein the foreign objects are dropped to a collection tank and the fluid bed particles are carried upwardly by a stream of classifying air to a deentrainment chamber where their velocity is reduced and they are returned to the combustion chamber.