1. Black Powder Removal from Transmission Pipelines Diagnostic & Solutions
Lindsay McRae – Pall Australia
Kaustubh P Chitale – Pall India

2. What is ‘Black Powder’?
Generic word designating typically various forms of iron sulfide, iron oxide, iron carbonate
Contaminants like sand, pipeline debris, liquid HC… can also be present
Global phenomenon, potentially any kind of transmission lines (gas, condensate, LPG…)
Formation due to internal reactions with steel:
Chemical: internal corrosion in presence of water, acidic compounds (CO2 / H2S), oxygen
Biological
Presence of water inside pipelines due to condensation of water vapor, or due to process upsets

3. Consequences of presence of Black Powder
Erosion of control valves
Erosion of gas meters
Erosion of pipelines
Deposits inside compressors
Fouling of instrumentation
Operating issues at end users
Complaints from end users
etc…
Erosion Damage on 12-Inch Control Valve Body (top) and Trim cage (bottom)
(By Courtesy of a Middle East oil company)

4. Solutions for removal of Black Powder
Possible approaches to overcome Black Powder issues:
Elimination of root causes (moisture…)
Internal pipeline coating
Separation technologies

5. Solutions for removal of Black Powder
Various solid/gas or solid/liquid separation technologies available on the market
Typically usage of filters or cyclone separators
But removing Black Powder efficiently is difficult !
Reality:
Black Powder particles are very fine (typically <10-15µm)
Nominal rated filters are not effective enough
Cyclonic separators have limited removal performances, and efficiency drops with changes in operating conditions

6. Solutions for removal of Black Powder
Black Powder particles are very fine (typically <10-15µm)
(results from Pall site survey on condensate)
(results from Pall site survey on gas)
10-15µm
18%
5-10µm
75%

7. Solutions for removal of Black Powder
Nominal rated filters are not effective enough
In practice, particles larger than the pores pass through nominal filters
Absolute rated filters are recommended for a reliable and reproducible quality
Source : “Principles of Filtration - Scientific & Technical Report WER 5300, Pall Corporation”

8. Diagnostic of Black Powder issues
Selection of suitable solution requires a good understanding of the problem
Characteristics of Black Powder
Total Suspended Solids content (TSS)
Particle Size Distribution (PSD)
Root causes
Nature (chemical composition)
Scrutiny of process data (high dew point,…) or pipeline history
Site survey capabilities and technical expertise can be proposed if lack of data

9. Diagnostic of Black Powder issues
Site survey capabilities:
Isokinetic sampling using portable membrane disc holder and isokinetic probe
 collection of solid contamination

10. Diagnostic of Black Powder issues
Site survey capabilities:
Laboratory means to exploit field samples
Optical microscopy
Scanning Electron Microscopy
X-ray analysis

11. Diagnostic of Black Powder issues
In addition to experience, results of site survey may be useful for:
selection of suitable locations for implementation, technologies and sizing
better understanding of root causes of particles
10-15µm
18%
5-10µm
75%

12. Case Study Middle East plant receives natural gas from network
Gas used as feedstock, requires compression stage, and as fuel gas
Nm3/h, 40 barg, 45 degC
Compressor and turbines protected by filter equipped with non-Pall nominal glass fiber pleated cartridges
Vessel diameter 800mm, with 27 off filter elements
Problems:
Filter elements replaced every 1-2 days to 2 weeks
Filter not able to handle design flowrate as clean DP almost max allowable
Heavy deposits on compressor

13. Dry black sludge - Stored in drums
Case Study
Replacement of filter elements lead to very heavy maintenance
Due to pyrophoric property of this Black Powder, filter vessel was filled with water, sludge drained from vessel and disposed of in drums
Non-Pall filter elements
Dry black sludge - Stored in drums

14. Case Study
Pall proposal: replacement of existing nominally rated filters
High dirt removal capacity, absolute rated, depth filter media technology (Pall ‘Coreless’)
Pall supply:
2 filters (1 duty / 1 stand-by), ID 1280mm, equipped with 30 off Pall ‘Coreless’ cartridges each for Black Powder removal
2 liquid/gas coalescers (customer request), ID 950mm, equipped with 12 off Seprasol™ Plus cartridges each, for liquid removal
Plant also purchased cyclones as pre-treatment stage, to implement upstream of filters

15. Pall ‘Coreless’ filters
Case Study
6’’
Pall ‘Coreless’ filters
40’’

16. Case Study
Plant commissioned Pall Filters and Coalescers without the upstream cyclone
To date after 15 months of operation, Cyclone not been installed yet
Since start-up Pall Filter has been operating at low DP (now ~400 mbar), and no change-out of cartridges since then
All downstream equipment are fully protected, plant fully satisfied

17. Case Study
After 6 months operation, client requested Pall to perform performance test
On-line measurements carried out upstream & downstream Filter
Upstream
Pall Coreless
filter
Downstream
Pall Coreless
filter

18. Conclusion Black Powder particles are very fine
Black Powder is difficult to remove efficiently
Fine separation technologies are required to protect downstream equipment reliably
Site survey capabilities are useful to understand the situation and to address the problem correctly

19. Thank you for your attention Any questions ?
How to contact Pall :
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