Plant and process for low-temperature fractionation of air

A plant for low-temperature separation of air, having

• a rectification column system having a high-pressure column, a low-pressure column, an argon column and a pure oxygen column, and a cold box system, wherein
• the pure oxygen column and the argon column or a base section of the argon column are arranged side by side such that an orthogonal projection of at least one upper part of the pure oxygen column onto the horizontal plane (H) does not overlap with the orthogonal projection of the argon column or the base section of the argon column onto the horizontal plane (H),
• the pure oxygen column has a feed point for a first transfer liquid and the argon column or the base section of the argon column has an extraction point for the first transfer liquid, wherein the pure oxygen column and the base section of the argon column are arranged such that the extraction point for the first transfer liquid is geodetically above the feed point for the first transfer liquid,
• wherein
• the low-pressure column is divided into at least a base section and a top section,
• the base section and the top section of the low-pressure column are arranged next to one another in such a manner that an orthogonal projection of the base section of the low-pressure column onto the horizontal plane (H) does not intersect with an orthogonal projection of the top section of the low-pressure column onto the horizontal plane (H),
• the high-pressure column is arranged below the base section of the low-pressure column in such a manner that an orthogonal projection of the high-pressure column onto the horizontal plane (H) intersects with the orthogonal projection of the base section of the low-pressure column onto the horizontal plane (H),
• the pure oxygen column and the argon column or the base section of the argon column are arranged side by side such that an orthogonal projection of at least one upper part of the pure oxygen column onto the horizontal plane (H) does not overlap with the orthogonal projection of the argon column or the base section of the argon column onto the horizontal plane (H),
• the cold box system has a first cold box, a second cold box and a third cold box,
• the high-pressure column-together with the base section of the low-pressure column is arranged in the first cold box,
• the top section of the low-pressure column is arranged in the second cold box,
• the argon column or one or more sections of the argon column is or are arranged in the third cold box, and
• the pure oxygen column is arranged in the second cold box.