Anaerobic Digester Stainless Steel roof access

[JohnWeal]

Good afternoon

We are having many questions asked by the client regarding digester roof access.

The roof is stainless steel 316L and has 4mm sheets bolted from the underside of the radial roof beams. Therefore any components exposed to the gas are SS 316L. As the roof beams are not in contact with the gas, they are galvanised mild steel.
The roof angle is 13 degrees.

We have 12 injection lances for anti foam. The issue is that there are access issues that the client has with walking up to the nozzles for maintenance purposes.

I would be grateful if anyone can give any advice on methods of accessing nozzles half way up the tank roof.
The tank diameter is 22.9m

Best regards
John

 

[bimr]

A picture or drawing would help to understand the issue. Have you considered installing a walkway around the roof half way up the tank roof?

 

[JohnWeal]

Hello bimr,

Yes we have and I think that is what we are going to have to do.

The nozzles are inspected on a 6 month basis.

Thank you for your reply.

Regards
John