Transcript Material and value flows - Policy Studies Institute

Management of produced water on
offshore oil and gas production
facilities:
comparative assessment
using flow analysis
Paul Ekins and Robin Vanner
Policy Studies Institute
[email protected], [email protected]
Offshore Forum, London
February 8th 2005
Background to study
UKOOA
[UK Offshore Operators Association]
Policy Studies Institute
Material flow and sustainable development work
Sustainable development work
Professor Ekins & Robin Vanner
Collaborative two year study under DTI LINK programme funded by
EPSRC
Study objectives:
1.
Direct benefit to oil and gas sector
•
2.
Four industry issues covered
Develop a generic sustainable business model
•
Use material flow analysis combined with their values
Approach to material flow analysis
Input C
t, £, e
Input A
Production X
Product B
t, £
£
t, £
Mass balance
Private values
Inputs = Outputs
£Product(B) > [£Inputs(A,C)
+ £Process(Y) - £Waste(D)]
Waste D
t (£?)
Input F
e, £, e
End of pipe Y
Waste G
£
t, value
Implicit social valuation
Waste E
t, value
-£Input waste(D) > Value[F+Y-(G+E)]
Is D worth that?
Industry case studies
1. Decommissioning of offshore structures
Material value of recycling, combined with implicit social valuation of
non-financial outcomes
2. Produced Water
Material implications of end-of-pipe cleanup technologies, stakeholder
perception of harm and the precautionary principle
3. Energy use offshore
Life of field view of energy use and material flows leading to indicators
and ultimately efficiency measures
4. Corporate relationships
Through a number of case studies, seek to understand stakeholder
issues and relationships in the context of an industry in transition.
What is produced water?
• Produced with oil
– In the UK in 2002; 272mt produced water, 105mt oil (72% of fluids)
• Physically separated from oil to leave water with a
dispersed oil content of typically ~20ppm (mg/l)
– Some dissolved content (aromatics and phenols) – toxic i.e capacity for
harm rather than actually causing harm
– Not feasible to biologically treat offshore
• Typically discharged into the North Sea
– Of the 272mt produced by the UK sector in 2002, 5.4kt was dispersed
oil (represents ~6% of total oil inputs into North Sea from all sources)
– Volumes tend to increase as fields mature
• OSPAR has recommended that total dispersed oil
content is reduced by 15% (baseline 2000) by 2006
– Represents a 36% reduction against expected 2006 discharges
– Open to UK sector wide trading scheme
Harm and uncertainty?
A range of stakeholder views of harm
• Some stakeholders would require an effect to be proven
and detrimental for a produced water discharge to
represent harm
– What about uncertainty and the precautionary principle?
• Others stakeholders only require for produced water
discharge to have the potential for having an effect for it
to represent harm
– What if an effect is not posing any impact on an organism?
– Adams 2002; uncertainty will lead to stakeholders applying culturally
based ‘risk filters’ to perceived ‘virtual’ risks
• DEFRA and the precautionary principle:
– “Where there are threats of serious or irreversible damage, a lack of full
scientific certainty must not be used as a reason for postponing costeffective measures to prevent environmental degradation”
• What is cost effective?
• What if end of pipe wastes could cause serious or irreversible damage?
Advanced cleanup technologies
1. Filter
•
Produces hazardous and low grade radioactive waste
2. Re-inject into well (PWRI)
•
a)
b)
c)
Requires significant energy to power injection pumps
Inject into available well
Drill new well and inject produced water
Substitute for existing water injection required to increase
pressure
3. C-Tour – extraction of some actually dissolved
content using solvent produced on the facility
4. Epcon – advanced tank separation
All require present physical pre-separation
Material and value flows
2006-2012 case study
Inputs
Outcomes
(1) Filtration of produced water
CAPEX/
OPEX
Filter
canisters
Removed
oil
t
80
450
490
£m
£7.6m/
£0.5m
£3.4m
-
Special
waste
=
% < in max Risk
(PNEC)
Costs
940
BTEX
1%
£50k/t oil
-£4.2m
PAH
6%
£15.7m
(2) Re-injection (PWRI)
CAPEX
Fuel Gas
Removed
oil
t
134
225,000
490
£m
£12.2m/
£0.5m
£8.5m
-
tCO2/t oil diverted
CO2
=
% < in max Risk
(PNEC)
470,000
BTEX
-£3.0m
PAH
960t
None/
100%
Costs
£78k/t oil
£24.2m
Material and value flows
2006-2012 case study
Inputs
Outcomes
(3) C-Tour
CAPEX/
OPEX
Fuel Gas
Removed
oil
t
-
1,000
160
£m
£4.5m/
£0.5m
£40k
-
Waste
=
% < in max Risk
(PNEC)
Costs
-
BTEX
0%
£49k/t oil
-
PAH
3%
£5m
(4) EPCON
CAPEX/
OPEX
Flocculant
(Chemical)
Removed
oil
t
-
210
383
£m
£4.1m/
£0.5m
£?
-
Waste
=
-
% < in max Risk
(PNEC)
Costs
BTEX
0%
£19k/t oil
PAH
5%
£4.6m
Doing nothing may forego ~£1mt (£78m) of production
in order to comply with the required reduction in OIW
Private assessment
1.
EPCON is cheapest (£19k/t oil removed)
•
2.
If this is enough to meet reduction target
PWRI expensive (£78k/t oil removed) but provides a contingency
against further discharge regulation
•
•
3.
Case studies operator did not value fuel gas or CO2
May be as cheap as £9k/t if substituting for existing water injection
C-TOUR also removes actually dissolved PAHs and phenols, the
two groups of chemicals which are the components of most
concern
•
4.
The actually dissolved content is not covered by regulation
Filtration also good at reducing dispersed oil and risk
•
•
Waste management costs are a pessimistic view
The case study operator rejected filtration due to waste and project risk
Operators will make their investment decisions
based on their particular portfolio of assets and
their view of the potential for emissions trading
Regulatory assessment is more problematic?
1. All costs are present (2004) private values
•
~50% of which would likely be offset against tax
2. Waste and CO2 values are based on private valuations
and do not represent damage costs or social values
3. Imputed values are minimum implicit valuations (in
present terms) and therefore also do not represent a
social valuation
4. The Predicted No Effect Concentration (PNEC) risk
assessments are theoretical and supposedly
conservative
•
•
•
What about the precautionary principle?
Discharges of produced water are set to increase
What about the threat of climate change?
•
Oil and gas sector is in the EU ETS – Emissions from produced water
abatement therefore imply emissions reductions in other sectors
Regulatory assessment issues
1. In respect of the 15% sector wide reduction
and 30ppm concentration limit:
•
•
•
How effective are they at reducing perceived harm?
Does the perceived harm justify the costs (material and
financial)?
What potential is there for produced water ‘hotspots’ if there is
an unconstrained trading scheme?
2. Future regulation and continuous
improvement/reduction management
philosophy
•
•
•
Society can’t remove all risks – where to stop?
Good understanding and communication of risk required
Material flow (and value chain) analysis can highlight cross
media environmental issues and total process waste costs