Closure device and liquid container

A closure device for closing a liquid pouch, comprising:

• a base body formed as a one-piece element, comprising a flat flange edge for connecting the base body to the liquid pouch, and a portal structure with a main section, a first valve section and a second valve section, wherein the first valve section comprises a first opening that is accessible from the outside configured for inserting and withdrawing a fluid, and the second valve section comprises a second opening that is accessible from the outside and configured for inserting and withdrawing a fluid;
• a first valve element that is arranged within the first valve section for reversibly closing the first opening, and a second valve element that is arranged within the second valve section for reversibly closing the second opening, wherein
• wherein the first valve section is designed cylindrically, and at an outer side, comprises a circumferential recess and an adjacent circumferential protrusion for coupling the first valve section with a filling and/or withdrawal device, wherein the circumferential recess and the circumferential protrusion have a frustoconical cross-section, and
• the first opening and the second opening are arranged parallel to the flange edge.