Compact Separation for Produced Water Treatment Recent Developments

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1 Cover graphic should fill and not exceed the defined grey box. Compact Separation for Produced Water Treatment Recent Developments 22 September 2011 Dr Nigel Abraham - Product Manager NEL PRODUCED WATER AND ENVIRONMENTAL CLUB Meeting

2 Compact Desanding Divider graphic should fill and not exceed the defined gray box. hydrocyclones Compact Deoiling hydrocyclones Compact Flotation Units 2 Process Systems

3 Desanding hydrocyclones - Removal of solids from PW Aim - Removal of solids from (produced) water Solids erode, corrode, damage pumps, block reservoir in PWRI Generally require system pressure to drive fluids through the SL hydrocyclone. Capacity achieved by using multiple hydrocyclone liners in a pressure vessel. More flow required - more liners required, More available pressure less liners. Less onerous separation requirements may allow the use of large diameter single liners in a pressure vessel (cheaper) Solids removal is a function of flowrate physical properties of the fluids and hydrocyclone liner selection Used offshore, onshore, produced water, on river water and on oil (removal of solids from oil). Can be operated with a vessel underneath (accumulator) to catch solids Or with continuous underflow stream Cannot be applied to every application 4

4 More compact solid liquid hydrocyclones Reduce vessel footprint and CAPEX PACS system Cassette assembly Multi Packed Cyclone Units 5

5 Compact Deoiling Hydrocyclones Old packing arrangements (4in1), F Liner, G Liner 6

6 Retrofit to upgrade performance and capacity Replace 12in1 bundle with erosion resistant liners Replace 12in1 bundle with high efficiency K series liner 7

7 Evolution of hydrocyclone packaging More compact vessels Inserted Sandwiched Original Offset Modified Manufactured Offset Super Offset These arrangements are protected by patents 8

8 Number of Liners Compact Deoiling hydrocyclone vessel Reduce Vessel size - or increase flow capacity Limited by the nozzle diameter and the support plate spacing 1400 Effect of Km / Kq Packaging Arrangement on Vessel Size Inserted Sandwich Original Offset Modified Manufacture Offset Super Offset Vessel Size DN (mm) Assumptions : 150# vessel in duplex 17.5bar g and 90 o C 9

9 Compact Flotation Units - History The first CFU was invented in 2000/1. (The Technical Manager of TST was also co-inventor of the first CFU in 2001 and the inventor of the TST CFU). The first full scale unit was in operation may Since then more than 50 installations have installed CFU. Most as a polishing units, but also downstream of hydrocyclones and downstream of inlet separators. Today there are many suppliers of different CFU technologies. Basis for these (not TS CFU) are that several vessels are needed in series to achieve good performance when inlet concentration is high (>50ppm). TS CFU first sold in 2010 represents the new generation of high performance multistage single vessel CFU. (World wide patent pending) 10

10 TST CFU Development The TST CFU technology has been developed through testing in the laboratory and offshore at different locations in the Produced Water treatment process. The results have been analyzed and documented by an independent acknowledged institute. Testing has been undertaken in cooperation with operators in the North Sea area, Bohai Bay (China) and southern China 7 full scale CFU units been delivered, 3 CFU units and 1 Water Knock Vessel under fabrication. 11

11 TST CFU Technology The Technology is based on both induced and dissolved gas flotation. A combination of external gas injection and proprietary internals for mixing of gas and oil have been developed to achieve easy separation of this mixture from the water. The water can be treated through several stages within one vessel. Up to 4 stages in one vessel. Numbers of stages are depending on the application where the technology will be used. 12

12 CFU MS3 (Three stage vessel) 13

13 CFU MS2 Full Scale 140 m3/h 14

14 Verification of Performance The technology has been tested offshore at different places in the process: Outlet from 1 st stage separator Outlet from 2 nd stage separator Downstream of hydrocyclones on 1 st and 2 nd stage separators Downstream of degassing vessel Well head (WKO with 85-90% water cut) A high degree removal of oil droplets down to 1 micron has been achieved. 15

15 ppm OIW CFU Basic (1 stage) as Polishing Unit down stream Degassing vessel Inlet Outlet 16

16 % Volume frequency distribution % Volume cumulative distribution ,4 ppm OIW Oil droplet size distribution In/Out TST (1) D/S Degasser Diameter (µm) In TST Out TST In TST cum Out TST cum

17 ppm OIW 60 CFU Basic (1 stage) down stream 1 st stage Hydro Cyclones Inlet Outlet 18

18 ppm OIW Outlet values CFU MS3 ( 3 internal stages) down stream 1 st stage Separator Inlet values between 850 and 1000 ppm OIW

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23 Project for Middle East Four CFU vessels and four internal stages in each CFU Capacity 20,000, 30,000 and 2x45,000BPD Carbon Steel, Duplex internals OIW inlet: up to 3000 ppm OIW outlet: below 10 ppm 24

24 CFU for Gudrun, Statoil Two internal stages Capacity 140 m3/h = 22,000 BPD Duplex Steel Dimensions: 2,8 x 2,3 x 3,2 Weight empty:5,9 tons Operational weight: 8,3 tons OIW inlet: up to 50 ppm OIW outlet: below 7 ppm 25

25 Project for Anadarko, China Four internal stages Capacity 600 m3/h = 90,000 BPD Carbon Steel, Duplex internals Dimensions: 3,3 x 2,4 x 5,8 (top of PSV) Weight empty: 10,5 tons Operational weight: 23 tons OIW inlet: up to 1500 ppm OIW outlet: below 10 ppm 26

26 Project for Roc Oil, China Four internal stages Capacity 2x500m3/h = 2x75,000 BPD (Two individual systems) Carbon Steel, Duplex internals Dimensions: 5,2 x 4,0 x 5,2 (top of PSV) Weight empty: 21 tons Operational weight: 40 tons OIW inlet: up to ppm OIW outlet: below 30 ppm 27

27 Project for PVD, Vietnam Four stage CFU Capacity 210 m3/h = 32,000 BPD Carbon Steel, Duplex internals Dimensions: 2,6 x 2,5 x 5,0 Weight empty: 5,5 tons Operational weight: 9 tons OIW inlet: 50 ppm OIW outlet: below 10 ppm 28

28 TST CFU Pilot unit

29 What is new with the TST CFU Multiple separation stages within one vessel No need for several vessels in series Handles higher OIW inlet concentration No tangential inlet. More flexible design and reduced fabrication cost Less space required and easier to fit into existing installations Multiple internal feed distribution Better internal mixing and contact between gas bubbles and oil droplets Less sensitive to scaling up of vessels The technology is world wide patent pending 30

30 Competitive advantages vs. CFU and Other technologies Other CFU s: TST CFU has Higher performance than existing CFU s Less equipment (only one vessel required) Low weight Small footprint Less dependent of Chemicals than the first generation of CFU s Simple skid design Lower cost Existing technologies: Replaces Degasser vessel Replaces HC + degasser Replaces all other flotation technologies Less foot print required and less equipment weight No rotating parts No small bore openings 31

31 Summary Demonstrated some of Cameron s recent developments in reducing the size and weight of deoiling and desanding hydrocyclones and the vessels Introduced the second generation CFU, multi stage with enhanced performance and smaller footprint. 32