SOUR SERVICE MAT SELECTION 1

[mcisajp]

Is there any way to manage the following conditions with C/S ? . Please advice.. If not, could C/S+clad 3.2 mm be a reasonable and realistic option. Can INCO ALLOY SUCH AS GRADE 625 be a good option?. Is there any manufacturer that can do the piping and vessels material?

Thanks in advance for your participation

TABLE CONDITION 1:

P (psia)H2S (ppmv)CO2 (%)H2S %H2S (psia)CO2 (psia)
450.00 1600 6.6 0.16 0.72 29.7
450.00 480 6.6 0.048 0.216 29.7
450.00 460 7 0.046 0.207 31.5
450.00 24 17 0.0024 0.0108 76.5
450.00 68 16.2 0.0068 0.0306 72.9
450.00 12 19 0.0012 0.0054 85.5
450.00 18 18 0.0018 0.0081 81

TABLE CONDITION 2:

SAMES AS TABLE ONE BUT P IS 60 PSI


TABLE CONDITION 3: (P 525 PSI, T 90 F )

H2S,ppmV CO2%MOL GAS,MMPCED LIQ, BPD FREE H2O), BPD
10.20 7.87 132.50 625.10 735.40
66.62 11.73 175.40 1,334.50 1,576.10
42.70 10.09 307.90 1,976.60 2,312.20
44.95 10.68 307.90 - -
6.15 0.53 - 1,976.60 2,312.20
44.95 10.68 307.90 - -
- 1.00 277.80 - -
420.64 99.96 30.10 - -


TABLE CONDITION 4: (P 60-80 PSI, T 70 F )

H2S,ppmV CO2%,MOL GAS,MMPCED LIQ, BPD FREE H2O, BPD
16.29 9.19 45.90 303.00 347.90
8.14 6.67 93.20 286.80 576.40
37.56 10.36 62.50 184.90 222.60
8.45 7.47 193.80 891.70 552.40
16.97 11.95 46.10 483.30 425.20

 

[SJones]

In terms of "managing" with carbon steel, there are always ways - it's just whether the risk and economics stack up. 625 will readily handle the conditions quoted (even if the process stream is full of chloride - which you don't indicate) but you will pay heavily for what should be a fit and forget option. Chemical inhibition could be a possibility if the piping and equipment arrangement is conducive to it (but the mention of vessels suggests that it may be problematic). You get a cheaper capital expenditure up front but you then have the operating cost of chemicals and corrosion monitoring (and replacement if it goes horribly wrong). The first step in your analysis should be trying to predict how much carbon steel metal loss will occur under the various operating scenarios then you can move on to working out whether you would have to buy so much carbon steel that it becomes worthwhile going to a corrosion resistant alloy. The next question would then be which alloy? To answer that question look at

http://www.nickelinstitute.org/inde...words=craig&ci_id=6511&Submit.x=11&Submit.y=9

There are a number of other factors to consider and it is not straightforward to give an answer to the question in the way that it is presented above.

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/

 

[mcisajp]

Steve:

Thanks for the web address. Craig ARTICLE looks VERY INTERESTING.. however is not electronic ... . I look and I could not find it... DO you know of any special site?

Thanks

 

[SJones]

The Craig article is a downloadable pdf file.

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/