Abstract: A method of an apparatus for heat processing of glass and/or glass forming material wherein cullet and/or the raw materials needed to form glass are heated while suspended in a high temperature gas stream which may comprise products of combustion. The particles heated both in and downstream of a burner, for example, together with products of combustion are accelerated out of the burner, preferably downwardly, through a nozzle and against a closely spaced impact surface in a separation chamber. Upon impact, the particles and/or molten droplets are separated from the products of combustion by adhering to the impact surface and form a continuous flowing layer which flows from the impact surface, over a flow surface and as a molten layer into a pool of molten glass product at the bottom of the separation chamber.