SUCCESSFUL TECHNOLOGY SETUP FOR WINTERSHALL - ZERO DISCHARGE AT TRANA
During the drilling operation on Seadrill`s West Hercules for exploring the Toutatis well, Norwegian Technology were responsible for zero discharge and treated all slop water to an average oil
in water value of 1,1ppm.
The majority of the chemicals utilized for the slop water treatment will be found in the sludge, and therefore not be discharged to sea.
Summary of treatment data is as follows:
Slop treated and OiW concentrations
• Sludge treated: 338 m3
• Treated water discharged to sea: 363 m3
• Sludge generated: 31 m3
• Slop volume reduction as a result of treatment: 90,8 %
• Average oil in water (OiW) concentration
in treated water discharge:
OMD- 24 Cell: 1 mg/l
Infracal: 1,1 mg/l
GC/FID (Westlab): 0,90 mg/l
• Corelation between (OiW) analysis
6 November: OMD-24 Cell average: 0,5 mg/l, Infracal 0,6 mg/l, GC/FID (west lab): 0,61 mg/l
18 November: OMD-24 Cell average: 1 ppm, Infracal 2,2 mg/l, GC/FID (west lab): 0,90 mg/l
The majority of the chemicals utilized for the slop water treatment will be found in the sludge, and therefore not be discharged to sea. This is valid for Nature NCS and Nature NPX. The exact ratio found in the sludge and discharged water vary and depends on many factors. In the calculation above, 98 % of the chemicals were present in the sludge, leaving 2 % discharged along with the treated water. This data was base don a gestimation.
Nature pH+ dissolved in the water to adjust the pH. The distribution of pH+ will therefore be 91 % in the water and 9% in the sludge.