Abstract: In glass production, waste gases are usually produced which still have a residual temperature of 400.degree.-600.degree. C. even though they are normally used for preheating the fresh air for a glass melting furnace. To be able to utilize this residual energy effectively for the preheating of the raw materials for glass production, particularly cullet, the invention proposes to conduct the waste gases through a bunker (19) for the temporary storage of cullet (20) and to heat the cullet mixture (20) to up to 380.degree. C. during this process. According to a proposal of the invention, the cooled waste gases contaminated during the preheating of the cullet mixture (20) are conducted via a wet scrubber (26) before they are returned to the waste-gas duct (17) leading to the chimney or similar.