Environmental technological solutions for

reducing offshore production discharges in

the marine environment

Presented by:

• Andrew Grant

• Janeiro Meosa

1

Agenda

To pinpoint the nature and volumes of the

discharges.

To demonstrate how E.C.T reduces these

discharges.

2

Objectives To classify the type of pollutants.

To identify the source of discharges.

To describe the nature of produced discharges.

To highlight the current volume of waste.

To list environmental control technologies.

To illustrate how these technologies are utilized.3

Overview of oil and gas production Production is the operation that brings hydrocarbons to the surface

and prepares them for processing.

Production operations include:

bringing the oil and gas to the surface

maintaining production

purifying, measuring, and testing

4

Classification of production waste

Wojtanowics 2008 5

Source of Produced water• Generated from oil and gas extraction process.

• These include:-

Water native to production formation

Water injected into the formation

Chemicals added during production

Various well treatment solutions

Oil and water separation process (A.B. Doyle et al 2008)

6

Nature of offshore produced water.

• Formation water

oMeteoric water

oConnate water

oMixed water

• Adjoining level of the same formation (for e.g. below gas cap)

Produced water may also contain:

Dissolved organic compounds

• Nitrogen and sulfur containing compounds7

Magnitude/ volume of produced water

Argonne National lab 2015 8

Environmental control technologies

A.B. Doyle et al 2008 9

Environmental control technologies

• Source reduction – water shut-off technology

based on alteration of permeabilities or rock plugging

involves injection of a low-concentration polymer

Laboratory experiments have shown a proven mechanism

10

Environmental control technologies• Source separation–downhole oil/gas/water separation

• Source reduction with downhole water sink

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Bottom-hole unloading and re-injection

Separation equipment installed down

hole.

Uses gravity segregation mechanism

Uses hydrostatic drainage or in-situ

injection

First used in producing natural gas to

remove excess water.

Sometimes uses a hydrostatic head

inside the well

Well is dually completed

Wojtanowicz 2008 12

Downhole separation disposal system

Uses a dual system

Water separated downhole and re-injected into

disposal zone

Uses liquid-liquid hydrocyclone from Vortoil

separation systems

Uses a modified standard artificial lift

System is run on production tubing

Connected with a polished bore receptacle

Installed in a 7 inch liner string

A.B. Doyle et al 2008 13

Source reduction with downhole water sink

Wojtanowicz 2008 14

Controls coning

Can be used with downhole injection

Isolated disposal zone from drainage zone

Uses an impermeable stratum

Downhole water loop can be used as an

alternative technique

A theoretical technique.

Associated Wastes in the marine environment

• Associated wastes that exists during the production phase:-

Separator sludges

Produced sand

Contaminated soils

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Produced sands in the marine environment

• Unconsolidated sandstone reservoirs:-

Depth 800 - 1400ft

Made up of mostly sand-size grains

Permeability stems from 0.5 -12 Darcies.

• Susceptible to sand production. (smaller percentage of total waste)

16

Effects of sand production on the wellbore

Blocks the wellbore and creates down-hole cavities

Kills hydrocarbon production

Corrodes the well and disables surface equipment.

17

Causes of sand production on the marine environment

• Toxic particulates can harm marine life

18

Technological Methods

• Downhole completion methods

Resin Injection

Slotted Liners

Gravel Packing

• Sand separators

• Deck drainage equipment

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Feasibility and economics of treatment

• Less system disruption

• Less operator interaction

• Better controlled maintenance

• Higher reservoir mobility and development

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Conclusion

• Primary waste:- Produced water

• Secondary or associated waste:- Produced Sands

• ECT :

o Source separation–downhole oil/gas/water separation

o Source reduction with downhole water sink

o Hydraulic fracturing

• Feasibility and economics of treatment

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References• Environnement, V. (2015). VWS STREAMLINER™ Deoiling Hydrocyclones.

Vwswestgarth.com. Retrieved 16 February 2015, from http://www.vwswestgarth.com/en/ProductServices/producedwatertreatment/deoilinghydrocyclones/

• (2015). Retrieved 17 February 2015, from http://www.diva-portal.org/smash/get/diva2:696803/FULLTEXT01.pdf

• (2015). Retrieved 17 February 2015, from http://local.alfalaval.com/ko-kr/key-technologies/marine-essentials/phoenix-high-speed-separator/Documents/PLS00069-Phoenix%20system.pdf

• (2015). Retrieved 18 February 2015, from https://www.slb.com/~/media/Files/resources/oilfield_review/ors92/1092/p41_53.pdf 22

References• (2015). Retrieved 18 February 2015, from http://

local.alfalaval.com/ko-kr/key-technologies/marine-essentials/phoenix-high-speed-separator/Documents/PLS00069-Phoenix%20system.pdf

• Boem.gov,. (2015). Questions, Answers, and Related Resources | BOEM. Retrieved 18 February 2015, from http://www.boem.gov/Environmental-Stewardship/Environmental-Assessment/CWA/Offshore-Discharges-From-Oil-and-Gas-Development-Operations---FAQ.aspx

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Thank you for listening

Any questions?