A method of conveying fuel, such as bulk material, into a gasification reactor that has a lateral infeed opening can be practiced with device for conveying fuels into a gasification reactor comprising a bulk material container, a conveying pipe, into which a discharge of the bulk material container opens and which can be connected to a lateral infeed opening of the gasification reactor, and a mechanical conveying apparatus disposed in the conveying pipe, the conveying apparatus is formed by a hydraulically drivable plunger, which is movably guided in a first, cylindrical section of the conveying pipe, and in that the conveying pipe has an internal cross-section which decreases continuously in the conveying direction of the fuel in order to form a compacting cone in a second axial section that is downstream of the first section, wherein the second section is configured as an exchangeable pipe portion with another exchangeable pipe portion.