CIAXTON'S RESPONSE

Flowline Details

• Size: 2 inches
• Volume: 6 bbls 
• Length: 1,500 feet

Equipment Rig-Up

• HP 950 chemical injection pump
• 300-gallon blending tote tan 
• High-pressure pumping hose package 
• 10k lancing unit
• 36-cfm air compressor
• 2" diaphragm pumps
• Toolbox 

Deployed Think Incident Free (TIF) planning to ensure the work could be completed incident free. Conduced daily JSA and tailgate meetings to communicate the work to be performed and the possible hazards associated with the job. 

IES Treatment Recommendation
We recommend to confirm the tie-in point, verify current line pressure and MAOP, and to rig up and test all necessary equipment. Mix PipeRenew® solution at 6% concentration and then begin lancing into 2-inch pipeline and monitoring returns. After that,  Mix PipeRenew® solution again at 6% concentration and begin fluid packing the line at 0.50 BPM. Once fluid packed, isolate receiving side and pressure up the line and shut in the line at the injection site. Monitor pressure on receiving side of pipeline, mix PipeRenew® solution at 2% concentration and fully flush pipeline and confirm returns are free of solids. 

HIGH PERFORMANCE RESULTS

IES Treatment Summary

• Full communication was established after 48 hours. 
• Approximately 25% of the 1,500-foot pipeline was plugged. 
• Project completed incident free (IFO).

IES initially mobilized to EI 342C on October 9, 2017. 333 bbls of PipeRenew® was pumped from SSTI from October 14-25, 2017. IES demobilized on October 25, 2017, to allow for a two-week soak/residence time in the line. Approximately three bbls of solids were accounted for in cutting boxes. This does not include solids entrapped in oil sent to storage tanks on 342C while displacing the 4-inch pipeline with PipeRenew® from Botruc 40 at SSTI.
IES remobilized to EI 342C on November 6, 2017. Injection into pipeline from SSTI,commenced on November 7, 2017. 61 bbls of PipeRenew® were pumped, commencing at approximately 12:24 p.m. on November 7, 2017, and ending at approximately 2:26 p.m. on November 7, 2017. At 2:26 p.m. the line was shut-in with pressure placed on line at approximately 1,200 psi. Line pressure decreased to approximately 875 psi as of 7:00 a.m. on November 8, 2017. The line was opened flushed with sea water starting at 7:05 a.m. An entire line volume of 271 bbls of sea water was flushed through the line. Approximately 10 bbls of solids were recovered. Note that from 199 bbls pumped (at approximately 11:00 a.m. on November 8, 2017) until full line volume had been pumped (271 bbls), all returns on EI 342C were sea water with no trace of PipeRenew® or solids. Therefore, all solids recaptured occurred between 7:00 a.m. and approximately 10:45 a.m. Again, total solids recovered in cutting boxes totaled approximately 10 bbls.

Flushing was completed at approximately 12:25 p.m. on November 8, 2017. Subsequent to flushing with 271 bbls of sea water, Injection rates were established at 1:40 p.m. on November 8, 2017, 1.02 bpm, at 1,440 psi. A total of 6 bbls were pumped. Clean returns on 342C.

CUSTOMER CHALLENGE
From its installation in 2007, this subsea pipeline in the Gulf of Mexico experienced recurring paraffin and tar deposition problems that completely blocked flow. After acquiring the completely blocked line in 2013, the current operator used a high-pressure, low-rate pump to unplug the line and achieve partial flow. The line subsequently required complex, costly, and frequent remediations including hot-tap flushes, coiled tubing, chemicals, and biocides. The operator was forced to batch-flow the product, which proved uneconomical. The line was scheduled for abandonment.

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LOCATION: IRRI 4
STATUS : COMPLETED
REMARK: 100% SUCCESSFUL.

Control line leak Diagnosis
Injection of Sealant into SCSSV Control line, Cure leak
Pressure Testing and Return of Well back on Production.

CUSTOMER CHALLENGE
Segment 7943 – a 4-inch x 18,657-foot pipeline from the host platform at EI 342C to SST1 at EI 327 -- Fieldwood has experienced high pressure safety alarms on the pipeline since November 2016. The pipeline has experienced abnormally high flowline pressures for several years. The line was last flowed in April 2017 and has since been shut in. Total line volume is approximately 269 bbls.
In 2013, an attempt to remediate the line was executed by Blue Fin utilizing a product by the trade name “Inferno.” The actual chemistry behind this product was not provided by the client nor known by IES.
In 2015, a second attempt to remediate the line was performed with a The lance was deployed to approximately 800 feet from 342C when a very hard obstruction was tagged. Lancing operations were aborted at that time and no further attempts have been made to remediate the line.
Details of the third remediation attempt were not provided; therefore, no details are known by IES.
It is suspected a wrench may have been dropped in the line from EI 342C during construction operations carried out on the riser. A paraffin analysis completed by Blue Fin in April 2013 and two oil analyses by Blue Fin in 2012 and 2013 were provided by Fieldwood. Both oil analyses indicated the presence of paraffin and asphaltenes. The pipeline does not have any known damage.

CIAXTON'S RESPONSE
Based on the information collected and analysis of the deposition, it appeared the 4-inch oil pipeline likely contained a significant amount of deposition along the entire horizontal section of the line. As paraffin and other deposits accumulate in a line over time, the amount of pressure required to flow increases inadvertently, causing a reduction in flow across the line. To properly develop an effective project remediation plan, IES reviewed previous data for remediation treatments executed in the surrounding geographical area.
Proper pre-job planning, including a site visit, equipment selection, and proposed equipment layout allowed for a safe and effective job execution.

HIGH PERFORMANCE RESULTS

IES initially mobilized to EI 342C on October 9, 2017. 333 bbls of PipeRenew® was pumped from SSTI from October 14-25, 2017. IES demobilized on October 25, 2017, to allow for a two-week soak/residence time in the line. Approximately three bbls of solids were accounted for in cutting boxes. This does not include solids entrapped in oil sent to storage tanks on 342C while displacing the 4-inch pipeline with PipeRenew® from Botruc 40 at SSTI.
IES remobilized to EI 342C on November 6, 2017. Injection into pipeline from SSTI,commenced on November 7, 2017. 61 bbls of PipeRenew® were pumped, commencing at approximately 12:24 p.m. on November 7, 2017, and ending at approximately 2:26 p.m. on November 7, 2017. At 2:26 p.m. the line was shut-in with pressure placed on line at approximately 1,200 psi. Line pressure decreased to approximately 875 psi as of 7:00 a.m. on November 8, 2017. The line was opened flushed with sea water starting at 7:05 a.m. An entire line volume of 271 bbls of sea water was flushed through the line. Approximately 10 bbls of solids were recovered. Note that from 199 bbls pumped (at approximately 11:00 a.m. on November 8, 2017) until full line volume had been pumped (271 bbls), all returns on EI 342C were sea water with no trace of PipeRenew® or solids. Therefore, all solids recaptured occurred between 7:00 a.m. and approximately 10:45 a.m. Again, total solids recovered in cutting boxes totaled approximately 10 bbls.

Flushing was completed at approximately 12:25 p.m. on November 8, 2017. Subsequent to flushing with 271 bbls of sea water, Injection rates were established at 1:40 p.m. on November 8, 2017, 1.02 bpm, at 1,440 psi. A total of 6 bbls were pumped. Clean returns on 342C.