Abstract: A storage vessel (1) for liquid substances which are supplied to a consumer is provided with a device for cleaning the connecting pieces (7, 8, 13, 18) when the storage vessel (1) is changed, the storage vessel (1) having a connecting piece (13) provided with a shut-off device (15) and a coupling (16) for connection to a connecting piece (7) provided with a coupling (10) to a pressure gas line (3) with a shut-off device (5). The storage vessel (1) has a connecting piece (18) provided with a shut-off device (19) and a coupling (21) for connecting a discharge line (17) in the storage vessel (1) to a connecting piece (8) provided with a coupling (11) and a shut-off device (6) for supplying the substance subjected to the pressure gas in the vessel (1) to the consumer.