Blow-Off and Steam Vent Silencers successfully installed in re-converted Paper Mill in Northern Italy

Stopson Italiana’s solutions soundproof the restored historical newsprint mill in Mantua.

Beyond Power Generation and Oil and Gas, Stopson Italiana’s soundproofing solutions embrace the manufacturing sector as a whole.
One of the last relevant projects concerns the soundproofing of the recently converted paper mill in Mantua, Lombardy, performed with two types of silencers for different services: Blow-Off and Steam Vent.

The Blow-Off type is a typical expansion and absorption silencer, which is used before the system’s enactment.
The principal use is to clean the pipes, removing any solid bodies and residual debris after erection and installation. The expander has an horizontal configuration, located laterally to the body of the silencer, is built with higher thicknesses and usually three metal layers. It consists of a pipe with a closed end with a certain number of large holes to allow proper expansion of the fluid and any debris passing through the holes with no damages at the same time.

The silencer – which has a size of Ø 2500 mm x H 7000 mm – has been conceived to achieve a sound pressure level of 100 dB (A) at 20m, which is more challenging than the ordinary soundproofing capacity for this type of silencers.
Discharge conditions: maximum flow rate 135 T / h at 330° C

Due to its capabilities, the typical applications regard the pipes blowing and cleaning processes, as well as the resistance to huge water flows.

The second silencer – that was supporting a larger supply delivered by our partner Tecnoterm Energy S.r.l. – comprised the design, production and installation of a Steam Vent Silencer (SPM model).
The model chosen was specific to reduce the sound emissions generated by the medium and low pressure valve groups.
Produced with a dimension of Ø 2200 mm x H 2900 mm, the silencer provides a residual noise level of 85 dB (A) at 1 m, with a sound attenuation of 50 dB(A) (delivery scheduled for the end of January).

  • Discharge conditions: Maximum flow rate 135 T / h at 160 ° C for the low pressure; 430° C for medium pressure.

The typical applications of this type of silencer are the Revamping Mill Plants and Cogeneration Plants.


Our offering for Paper Mill application

Stopson Italiana has a wide range of product for Paper Mill applications, including Air Filtration, Duct Silencer, Acoustic Enclosures and Barriers, Steam Vent Silencers.
Our Vent Silencers are designed to reduce noise level of exhaust piping to the atmosphere for pressurized gaseous fluids, such as air, vapour, natural gas, nitrogen, oxygen, carbon dioxide, etc. They can be installed downstream any device acting as a link between a container of pressurized gaseous fluid and the atmosphere. The vent silencer can also provide high or low back pressure relief for the system ensuring proper operation.
Vent silencers can be reactive, absorptive or combined type depending on applications and required attenuation, which can reach as much as 75 dB(A).

Typical Applications for vent silencers are:

  • Safety Valve (PSV)
  • Relief valve (PRV)
  • Control valve
  • Ejector
  • Start up valve
  • Snort-valve
  • Flash and Blow Down Tanks
  • Blow-off

Stopson Italiana’s offering for plant Blow-off cleaning does also include additional services and materials as described below:

  • Engineering
  • Steam blow flange
  • Spectacle flanges with gaskets
  • Demi water pumps
  • Gate and globe valves
  • Thermocouples
  • Temperature and Pressure transmitters
  • Pneumatic target plates inserters
  • Installation
  • Blow-off Supervision