Vessel Degassing Case Study


Degassing and Clearing Tanks of LEL’s and VOC’s at Enterprise Products Morgan’s Point

A Case Study

In this case study we have chosen to share the daily email time line between EET’s Bill Summers and Enterprise Products personnel as the project progresses.

Bill Summers May 16
Monday 0645: arrive on site to sign-in and attend LR Ops meeting.
Week of; May 16 – May 20: daily, as required (weather?) 0700 to 1600.
Primary Mission: Clear, and prep for turn-over (blasting/inspection) Tank 161.
Secondary Mission: save/manage/separate retained fluids for circulation in tanks 162 and 161. Follow-up on tank 162 and 154 to effect smooth timely turn-over for follow-on work; as may be directed. Assist with removal and/or repositioning of Frac tanks. O/O review/walk other tanks as directed.

MP Monday Work Plan:
1) Consolidate and separate retained-fluids (3 frac tanks by 144/145): pump the best retained-fluid from frac tanks to TK 162 (50,000 gal more/less), and, circulate for several hours. and; relocate pump, additional hose, and lines/fittings as required. Any oily sub-standard fluid; to be moved to frac at 105, (note; separate Permit) as/when frac is available.
2) Mobilize and prep for clearing Tank 161; Meyers-unit/line/hose/fittings, 70bbl, compressor and copus fan; and, check volume of product (if any) remaining in TK 161; work with maintenance/operations to ensure lines/valves are secure and/or blinds are in place as directed.

MP Tuesday Work Plan:
1) Given, all-set on Monday; initiate top down clearing-attack, with, fresh/strong NEI on TK 161 utilizing Meyers unit: same procedure as 162/105. Continue to treat/clear until two test are confirmed clear; when approved; be prepared to circulate fluids from TK 161 to 162. Utilize copus fans and “froth” the fluids in bottom of TK 161 as necessary.
2) Check fluids TK 154; pull out any residue to get tank as dry as possible (fans) this may start on Monday and continue on Tuesday and Wed.

MP Wednesday Work Plan:
Follow-up and adjust (weather?) in order to complete TK 161clearing by COB.

MP Thursday Work Plan:
Complete additional work if necessary; Police site and de-mob; subject to further direction.
– Summers

Bill Summers May 19
TK 161: Much better; However, not there yet: as can not guarantee 100% ready, for entry early AM Monday. That said: think we can, and/or, may need to complete fluid removal on early Monday morning: and, can permit/start at 0630 tomorrow/Friday. (or, we can work about 3-4 hours Saturday)

1) Completed; Initial Top down attack; with Meyers Unit; 2,000 gal, strong fresh mix utilized and placed in tank: stirred that up from the top man-way with the Meyers Unit. LEL’s dropped to 0 then fluctuated back up and down. Added additional retained-product from the frac-tank reserve through the top of tank with the Meyers Unit; mixed from the top.
2) NOW; adjusting pump/lines to pump additional fluid into top tank161 (3 inch line) and return through a 4 inch line, passing-through a frac tank (or two) to drop/remove as much scale as possible. Will then add additional retained-fluid and circulate.
3) Today/or AM FRI: Copus Fan will be added (in the AM Friday, if not this afternoon)
4) Optional; will perform 2nd top down attack with Meyers Unit, Friday: to ensure results, while also, continuing to circulate on Friday. We may need part of Monday AM (??); can start early, 0630; to complete removal of as much fluid as possible from Tk161. and assist with hand off to the folks performing entry for scaffolding .
– Summers

McGrory, Pat May 19
Meeting with Anchor painting……………..they will start prep-work on Monday and plan for vessel entry on Tuesday. Great job today Bill……….thank you sir. Let’s work on completion tomorrow.

Bill Summers May 20

Pat: Per our phone call this afternoon; working tomorrow: starting at 0700; Kerry Liles will be lead until Karl comes in. I will be there for 2nd half of the day. John W. and Chris D. will be there/available to assist; also noted/understood, they may be on other task, too. NOTE: they both know Pat has approved. Both have been called; they will be there. Ex Summary; LEL’s knocked down today; not good enough, just yet; work continues tomorrow/Sunday: per, original work plan for the week of May 16: as originally determined from meeting/site-walk, Wed May 11.

MISSION: Clear TK161, reserve and decant fluids; and be prepared to transition follow-on work/entry of TK 161 on Tuesday May 24. TODAY’s/Saturday work completed: arrived on-site at 0630 and worked Permit:

* Completed top down on TK161 with Meyers Unit; 3,000 gallons strong-mix application.
* Pumped air with 70bb through 2 inch on bottom of tank, frothing; ran Copus fan.
* Circulated within TK 161.
* Coordinated/assisted with maintenance folks; for matting and moving of 2nd frac to TK 161 work area.
* Secured area and closed out permit 1600: reviewed with Ops, the anticipated work plan for Sunday.

SUNDAY May 22 WORK PLAN: Tank 161.
Equipment; same as Today/Saturday; in place and prepared/fueled for Sunday; and, 70bbl and mover for frac as/when needed.
1) Continue circulation in place; and/or, pump air/froth/mix into bottom of tank 161 with 70bbl; employ Copus. And, be prepared to utilize Meyers unit as determined by readings.
2) Arrange/assist moving/placement of additional matting; and, move the empty frac from 144/145 work area.
3) Concurrent with 2) above; move/decant fluids of francs at 144/145, to allow the one closet to the road to be pulled. Note: additional mats are available if required to assist in pulling/moving frac from 144/145 area. Mats then to 161.
4) Move fluids as necessary to allow, up to, 40,000 gallons of empty frac capacity within the TK 161 work area, in order to facilitate Tank circulation, and, scale removal, and later, to be able to drain tank for man-way removal.
5) Be prepared, with ops approval, to crack man-way and sniff; and, assemble/prepare special-tools; review plan, to remove man-way and connecting spool. continue copus. observe inside of tank 161 from man-way and continue work and/or adjust plan as may be then determined. Will provide recommended work plan for Monday/23. tomorrow/Sunday; after COB. Monday intent; continue work; additional treatment if required; verify and wrap up by COB Monday and ready to enter Tank 161 on Tuesday.

McGrory, Pat May 20
Thibodeaux……….can you assist Bill and Karl and Kerry first thing this morning? I think we CAN complete 161 today. And move everything to 162. Now, Monday looks iffy for work instead of today. Rene’ should be able to get the decking done today for the tank. Monday morning the vendor will be here for prep work and start to work on scaffolding/sandblasting for inspection…..on Tuesday.

Bill Summers May 22
Pat: Tank 161 LEL free at the top man-way and as far inside as we can get the meter-prob; as of COB today. Will be able to open lower man-way Monday, and, enter soon there after as/when needed. FOR MONDAY: Would be most helpful if John and/or Chris can attend Lanny’s 0700 meeting for coordination. Good team effort with them today; this was critical to moving mats and relocating 2nd Frac tank to TK 161 area.

Today’s Report: Followed the Sunday work plan as provided below; Pumped/circulated/aerated/frothed, and tested; thereafter, repeated until complete: and, remainder of mating moved. 2nd Frac was relocated to TK161 work area.

Arrive at operations before 0630; work permit (same as Sat and Sun) to allow early testing/confirmation of LEL; and, start fan and/or circulation/aeration per, reading. Equipment/lines are in place and ready to go as soon as permitted. Lanny/CD: A little help please for Monday AM; if things are not too hectic, we will attempt to get a permit started a little early, so we can get LEL readings before the 0700 meeting. Thanks.
1) Verify LEL staying at “0” and, adjust work accordingly until “0” levels are confirmed.
2) Given completion of, 1) above, move all fluid from TK 161 to the two frac tanks; observe and decant if necessary any move any spent/oily water to frac Tank 105 (Note; separate permit to move/fill). Outlet on Tk161 is just below man-way; this will remove the fluid to a level below the man-way.
3) Given 2) Completed; Assist Maintenance with lower man-way removal; crack, check, remove; thereafter, adjust plan, similar to 151/154 and remove as much of any remaining fluid and scale as possible; run copus and continue to check LEL levels. Make it smell, just like, or, as close to as possible, to the “Caribbean”.
4) Affect transfer to follow-on contractor. Be prepared to enter TK 161, if required, to ensure clear/dry.
5) Review plan for TK 162; adjust work-site, pumps/lines as needed. proceed with work on TK 162 as needed/directed.

Note: Tank 162 was clear; will check: Could circulate/froth if/as needed. Cannot open at lower man-way until empty.

Bill Summers May 23
Tank 161 remained clear all day today with multiple checks; including, after removal of lower man-way. Today: The Heavy-sludge material, that had emitted high VOC’s with resulting high LEL’s; out of limit readings before clearing; was pushed away from the lower man-way by spraying/pushing from the top man-way. Fan was run. Fluids checked/moved.

1) Verify LEL readings on TK 161 and adjust work plan accordingly. Could hit sludge with a small amount of NEI, for fast knock-down, if LEL higher than “0” is detected. Copus fan ready, as needed, at top man-way.
2) Given 1) above is complete, enter tank; full face respirator protocol; after approved and safety in place. Note: Special combined-joint safety review/brief prior to entry. Anticipate only one or two folks need to enter.
3) Move/slurry sludge to man-way into recovery pan; remove with 70 bbl, observe and separate fluid/scale sludge for removal to frac tank; Note: spent/oily-water to be moved to frac at TK 105. Note: separate permit to move within tank 105 area. Anticipate work complete within two hours of tank entry.
4) Remove/reposition select equipment/pumps/lines, and, Affect turn-over of TK 161 for follow-on work.
5) TK 162; set-up for circulating, scale reduction/removal by pumping, and, possibly removal of man-way and completion and clean-out by similar procedure as performed on TK 161.

Bill Summers May 24
Pat: TK 161 was turned over to follow-on crews: today 1130. Work plan adjustment, per our conversation this afternoon.


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