A dry-bulk tanker for the provision of binding agents for soil stabilization for a spreading device comprises a storage container (10) for binding agent. A mechanical conveying device (18) for conveying binding agents from the storage container (10) into an intermediate chamber (20) is connected to the storage container (10). A pneumatic conveying device (36) for conveying the binding agent to the spreading device is connected to the intermediate chamber (20). A pressure relief device (40, 41) is connected to the mechanical conveying device in order to avoid the entry of compressed air into the storage container (10). The invention furthermore relates to a conveying system for a dry-bulk tanker and to a work train for working soils with a self-propelled ground working machine and a dry-bulk tanker.