Germany – Installation of metal structures – Kläranlage Aurich-Haxtum, Bau Faulung II - Stahlbau

The subject of the tender is the new construction of the digestion on the Aurich Haxtum wastewater treatment plant. The Aurich-Haxtum wastewater treatment plant treats the wastewater of the city of Aurich and the surrounding municipalities. In addition to the predominantly municipal wastewater, dairy wastewater from the local Rücker dairy is also treated at the Aurich wastewater treatment plant. The current inflow load is approx. 68,500 EWCSB. To stabilise and reduce the primary sludge produced during wastewater treatment, a sludge digestion plant has been in operation at the wastewater treatment plant since 1963. Despite ongoing optimisations and renovations, the sludge digestion has reached its performance limit due to increased inflow loads. The existing digestion capacity is only limitedly sufficient for the primary sludge and the flotation sludge produced during the pretreatment of the dairy wastewater. The digestion process is sometimes overloaded and leads to difficult operating conditions. During maintenance and repair work on the digester (approx. 60 years old), no reserve capacities are currently available. It is currently not possible to also use the excess sludge (ÜS) for energy purposes, as the digester is already overloaded with a digestion time of far less than 20 days. Therefore, all ÜS sludge is stabilised in a composting plant. The operation of the sludge composting requires a lot of space, results in high sludge disposal costs and is generally uneconomical. In the long term, the operation of the composting plant is to be discontinued and the ÜS sludge is also to be fed to a sludge digestion for energy utilisation and sludge reduction. For this reason, the construction of a sludge digestion for the ÜS sludge is necessary. This includes the following measures:

- New construction of a digester for ÜS sludge incl. operating building

- Erection of a new gas storage and emergency flare

- Installation of a new CHP plant and digester gas purification

- (Installation of a sludge disintegration; planned later)

- (Installation of a receiving station for fats and co-substrates; planned later)

- Integration of the new construction measure into the existing plant and control technology

The Aurich wastewater treatment plant is located in Haxtum. Address: Kläranlage Aurich Haxtum Zum Antjebitt 1 26605 Aurich

Scope of services of the contract unit

The essential scope of services of the contract unit is listed below for each specialist trade.

- Trade 1 Earthworks (already commissioned)

- Trade 2 Earthworks

- Trade 3 Building construction

- Trade 4 Steel construction

- Trade 5 Roofing work

- Trade 6 Façade construction

- Trade 7 Door/Window construction

- Trade 8 Plastering work

- Trade 9 Screed work

- Trade 10 Tiling work

- Trade 11 Painting work

- Trade 12 Mechanical engineering

- Trade 13 EMSR engineering

- Trade 14 CHP engineering

- Trade 15 Demolition and dismantling of the former gas flaring plant