Multiphase Desander – Valve and Accumulator Size and Selection (B-FSM093)
This article will cover primary valve and accumulator size and selection for a multiphase desander from a process point of view. The mechanical design of valves will be covered in a future article.
Isolation (DBB) Valve Size
- The main operating valve lies between the desander and accumulator. At high pressure operation is it usually a double block and bleed configuration (DBB)
- Valve must be gate valve, with slab type preferred
- Valve flow path diameter must not be smaller than cyclone insert apex diameter (i.e. 10” insert has 3” apex, so valve flow path should be at least 75 mm)
- Flow path diameter may not be indicative from valve nominal size. Check valve drawing to ensure full port valve and diameter is sufficient.
Accumulator (ACC) Sizing
- Typically 2:1 or 3:1 aspect ratio (height:diameter)
- Total volume for reasonable collection time (8-12 hours at least)
- Recommended solids fill height ~75%
- The quantity of solids reporting to ACC equals inlet concentration to WHD multiplied by separation efficiency
- Volume of solids must be corrected for particle packing efficiency (0.62 average) – 100 liters of particulate solids packs at 161 liters effective volume
Multiphase desander application and operation will be covered in the next article.
- Rawlins, C.H. 2017. “Separating Solids First – Design and Operation of the Multiphase Desander”, paper 185658-MS presented at the SPE Western Regional Meeting, Bakersfield, CA, 23-27 April.