Storage Tank Assesment (Bundwall, Sprinkler, CP and Breather valve)

[Zachari_alamsyah]

i am API 653 Inspector which have to do perform the storage tank with refers to API 650/653 Standard, The Tank is ECSB (External Circulated Sludge Bed) Reactor which treating waste-water using bacteria.The tank is not passed the hydrostatic test (any leak occur), but i have to do an assesment related to design (eventhough is not operation mode yet, so 653 cannot be as reference to do this assesment)
i have question regarding with tank assesment:

1. the tank is not equipped with proper bundwall, is there any requirement in API 650/653 standard which is the using bundwall is mandatory as secondary containment , or any NFPA standard which regulate the using of bundwall around storage tank?

2. The tank is not equipped with fire water main ring and sprinkler, is it mandatory to using fire protection around the storage tank?

3. The tank is not using Cathodic protection either Sacrificial anode or Impressed current, is there any mandator requirement that the tank should be protected with CP protection?

4. The tank is not equipped with breather valve, but have frangible roof joint as emergency venting. is it possible not to using PVRV (Breather valve) to protected tank from vaccum or overpressure inside the tank?

Thank you for your responses

 

[HTURKAK]

The scope of API 650 standard is ; the storage of petroleum, petroleum products, and other liquid products.

You may design the mentioned External Circulated Sludge Bed Reactor as per API 650 but, the requirements for petroleum, petroleum products should not apply.

Regarding your questions,

1- Secondary containment by constructing dike or berm walls around a tank is a general rule for petroleum tanks . For your case, should not be valid.. In case of rupture of the tank the dike can impound the sewage water but can you impound the ODOR ??

2- I could not see the requirement for fire protection of the tank.. fire water ring , sprinkler, and foam fire-fighting are applicable for petroleum, oil and gas products..

3- CP with sacrificial anode is a general rule for water tanks ..You did not describe the coating. IMO ,CP with sacrificial anode should be an option for this tank.

4- The picture is not readable. If you post the tank design data sheet and piping , the requirement for vacuum or overpressure could be seen .

There is another forum (wASTE DISPOSAL & TREATMENT ).. I will suggest you to post your queries to that forum to get better responds..

Good Luck..

 

[MJCronin]

Suggest that you post your documents in a .pdf format and check their readability

1[b]. the tank is not equipped with proper bundwall, is there any requirement in API 650/653 standard which is the using bundwall is mandatory as secondary containment , or any NFPA standard which regulate the using of bundwall around storage tank?
[/b]
The placement, design and proper materials for a tank farm bund system is not covered By API 650/653. I am a little surprised that you are asking this question, Do you have access to and have you read API 650/653 ? The NFPA document most related to tankfarms and bund system design is NFPA-30. The bund system design for all tanks within a tank farm should be part of a general spill containment and management fire protection review



4. The tank is not equipped with breather valve, but have frangible roof joint as emergency venting. is it possible not to using PVRV (Breather valve) to protected tank from vaccuum or overpressure inside the tank?


No, the tank must be protected against destructive vacuum and overpressure by normal and emergency venting system. Frangible roofs were an ancient emergency attempt to protect tanks from a pool fire. They are now discredited and certified emergency venting devices are preferred. There were severe doubts if frangible roofs would operate in severly corroded tanks or tanks below about 30ft diameter

Is this the first tank design that you have ever reviewed ???



MJCronin
Sr. Process Engineer

 

[JStephen]

1) Containment dikes, leak-detection liners, etc., may be mandated by environmental regulations and may be affected by fire-rptection considerations. If the tank contents are flammable, NFPA 30 or similar documents may apply.
2) Fire protection provisions may be affected by fire codes, and are not normally used if the tank contents are not flammable.
3) The decision to use cathodic protection is an economic consideration, and depends on corrosion conditions and soil conditions, etc. Note that if a tank contains water, you can use cathodic systems both inside and out.
4) The tank should include some type of pressure/vacuum valve or free vent. In addition to that, if the product is flammable, it may require a frangible roof or an emergency vent- again, see NFPA-30. Note that the definition of "frangible roof" in API-650 may differ from that in other codes, and that many medium/small diamter tanks will not qualify as "frangible".

 

[MJCronin]

.... kinda like what I said ...

MJCronin
Sr. Process Engineer