Environmental technological solutions for

reducing offshore production discharges in

the marine environment

Presented by:

• Andrew Grant

• Janeiro Meosa

1

Agenda

• We are going to pinpoint the nature and volumes of

the discharges, as well as to list and explain the

effectiveness of environmental control technologies

in meeting the required effluent limits as

determined by regulating bodies.

2

Objectives• To classify the type of pollutants.• To identify the source of produced discharges.• To describe the nature of offshore discharges.• To highlight the current volume of discharges.• 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, and purifying, measuring, and

testing.

4

Classification of production waste

5

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

• These include:-

o Water native to producing formation

o Water injected into the formation

o Chemicals added during production

o Various well treatment solutions

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

6

Magnitude/ volume of produced water

Argonne National Lab 2015 7

Nature of offshore produced water.• Formation water• Adjoining level of the same formation (for e.g. below gas cap)• Formation water can be further classified as:

Meteoric water Connate water contains mainly NaCl Mixed water Produced water may also contain:

Dissolved organic compounds Nitrogen and sulfur containing compounds

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

• Three basic mechanisms of in situ gelation of the injected slug : polymer crosslinking reversible gelation sol stabilization

A.B. Doyle et al 2008 10

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

• Source reduction with downhole water sink

11

Environmental Control Technologies Bottom-hole unloading and re-injection

A.B. Doyle et al 2008 12

Environmental control technologiesDownhole separation– disposal system

A.B. Doyle et al 2008 13

Environmental Control TechnologiesSource reduction with downhole water sink

A.B. Doyle et al 2008 14

Associated Wastes in the marine environment

• Associated wastes that exists during the production phase:- Separator sludges Produced sand Contaminated soils

15

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• block the wellbore and create downhole cavities• Kills hydrocarbon production• corrodes the well and disables surface equipment.

17

Causes of sand production on the marine environment

• Removed hazardous particulates that are overall harmful • Irregular shift in tectonic movement

18

Technological Methods• Hydraulic fracturing – screen liner• Water waste treatment separation• Deck drainage

19

Feasibility and economics of treatment• Sand production prediction• No system disruption• Less operator interaction• Better controlled maintenance• Higher reservoir mobility and development

20

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

o Better controlled maintenanceo Higher reservoir mobility and development

21

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

22

Thank you for listening

Any questions?

23