Transhipment Plant Sedrun

On behalf of Arge Transco Sedrun, STAG engineered, built and successfully commissioned, in 2003, an extraordinary transhipment plant for bulk products such as cements, ashes and microsilica necessary for the construction of the world’s longest railway tunnel.  


The bulk materials were delivered by Rhaetian Railway, then pneumatically blown into the silo system and afterwards pneumatically transported, on request, over a longer distance into the concrete mixing facility situated 900 m below at the pit bottom. Due to the unique nature of this large-scale project, STAG AG as the system supplier had to address enormous challenges in all project phases, and managed to master these challenges with great success.  

Essential Information

Applied Main Components for the Portal

  • Rail wagon unloading station
  • Silo plant with steel works and integrated compressor station
  • Fluid air slides as silo discharge system for feeding into the pressure conveying vessels  
  • Pressure conveying vessel (tandem)
  • Conveying line
  • Compressor conveying and control air
  • Compressor control air
  • Ventilator fluid air slides
  • Conveying screw (microsilica) with container loading facilities
  • Electric cabinet including plant control

Pit head

  • Pneumatic pressure discharge conveying (tandem)
  • Dense phase conveying line (Denseflow)



  • Technologically demanding plant control System


  • AlpTransit Gotthard AG
  • Arge Transco Sedrun


Technical Information
Systems Conveying rate Conveying distance
Pneum. Cement conveying portal-pit head 25 t/h 1'100 m
Pneum. Cement conveying pit head –pit bottom 25 t/h 940 m
  • Rail wagon unloading station
  • Silo plant for storage of cements and microsilica
  • Pneumatic transport of cement
  • Dense phase conveying lines (Denseflow)
  • Conveying and control air treatment stations (compressor)
  • Plant control system
  • Microsilica loading from silo into containers provided by the customer
Bulk Material
Bulk Material Grain size Moisture content Bulk density Temperature Property
Div. cements - < 0.2 % 1.1 kg/dm3 < 80 °C not abrasive
Microsilica - - 0.6 kg/dm3 - not abrasive
Appropriate Topics
Pressure Conveying Vessel

The pressure conveying vessel is used by STAG when it comes to challenging tasks, high conveying rates and long con-veying distances. This pneumatic conveying application using the dense flow method combines energy-optimised conveying processes with perfect operational safety.

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Repair Machines

We are happy to carry out the necessary revision of replaced machine components. Send us your aggregate to Maienfeld and we will inspect and revise it. Experienced mechanics and plant and apparatus engineers inspect the unit.

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Dense Phase Pipe "DenseFlow"

In conventional conveyances of powdered bulk materials through smooth pipes, the irregularity of the flow rises with the increasing pipe length. This in turn, increases the wear of the system.


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