Stabilisation/solidification of synthetic drill cuttings - - PowerPoint PPT Presentation

International conference on Stabilisation/Solidification Treatment and Remediation, Cambridge 12-13 April 2005

Stabilisation/solidification of synthetic drill cuttings Stabilisation/solidification of synthetic drill cuttings representing Ras Shukier oil field in Egypt representing Ras Shukier oil field in Egypt

UNIVERSITY OF

CAMBRIDGE

• M. S. Al
• M. S. Al-
• Ansary

Ansary & A & A. . Al Al-

• Tabbaa

Tabbaa

Outline Outline

I. I.

Oil Drill Cuttings Oil Drill Cuttings

II. II.

Ras Shukier Case Study Ras Shukier Case Study

III. III.

Experimental Work Experimental Work

IV. IV.

Ongoing programme Ongoing programme

V. V.

Conclusion Conclusion

• Cla

Cla

Drill cuttings are heterogeneous wastes Drill cuttings are heterogeneous wastes that are generated from petroleum drilling industry that are generated from petroleum drilling industry

Drill fluid Circulation System Drill fluid Circulation System Recycled Recycled fluid fluid Drill Cuttings + Drill Cuttings + fluid fluid Drill Cuttings Drill Cuttings contaminated with contaminated with chemicals from chemicals from fluid fluid & oil & oil

Treatment methods for drill cuttings Treatment methods for drill cuttings

• Leave in place

Leave in place-

• disturbed

disturbed

• Leave in place

Leave in place-

• undisturbed

undisturbed

• Entombment

Entombment

• Capping

Capping

• Gravel Dumping

Gravel Dumping

• Bioremediation in situ

Bioremediation in situ

• Bio

Bio-

• reactor

reactor

• Land Farming

Land Farming

• Mechanical Dredging

Mechanical Dredging

• Crawler retrieval

Crawler retrieval

• Re

Re-

• injection

injection

• Re

Re-

• spreading

spreading

• Mechanical separation

Mechanical separation

• Distillation

Distillation

• Stabilisation

Stabilisation

• Combustion

Combustion

• Supercritical extraction

Supercritical extraction

• Thermal

Thermal Desorption Desorption

II.

• II. Ras Shukier Drill Cuttings

Ras Shukier Drill Cuttings

Ras Shukier is an offshore oil production site located in the Gulf of Suez, Red Sea,

• Egypt. This site

generates approximately 2,740 tonnes

• f cuttings per year. Ras

Shukier consists

• f

nine complex platforms.

Transportation Service boat Approved disposal by Environment

Offshore Onshore

Waste Disposal Area

Drill Cuttings

Manifest by Load Master Manifest by Toolpusher Cutting Box Drilling Rig

Physical and Chemical Characteristics Physical and Chemical Characteristics

• Brownish black, sticky with a clayey texture soil.
• Distinctive crude odour.
• Density ranges between 1.2 and 2.0 g/cm3.

(w/w) (w/w) Hydrocarbon% Hydrocarbon% Cr% Cr% Zn% Zn% Ba Ba% % Pb Pb% % Cl Cl% % 0.1 2.1 9.2 0.3 0.2 1.2 0.2 0.6 0.1 0.4 11.0 11.8 Average Average Max Max

III.

• III. Experimental Work

Experimental Work

Synthetic drill cuttings and their properties Synthetic drill cuttings and their properties

Soil composition % Sand content 10 Silt (rock flour) content 50 Clay 1 (kaolin) 20 Clay 2 (bentonite) 20 Property Value Water content 20% pH 9 Plastic Limit 25% Liquid Limit 51% Cutting composition % Sodium Chloride 3.5 Paraffin oil (of dry soil) 11

Binder System Binder System

• A. Conventional Binders
• A. Conventional Binders
• Portland Cement (PC)

Portland Cement (PC)

• Lime

Lime

• Pulverised Fuel Ash (PFA)

Pulverised Fuel Ash (PFA)

• Blastfurnace

Blastfurnace Slag (BFS Slag (BFS) )

• B. Novel Binders
• B. Novel Binders
• MgO

MgO cement cement

• Zeolite

Zeolite

• Microsilica

Microsilica (silica fume) (silica fume)

• Cement Kiln Dust (CKD

Cement Kiln Dust (CKD

• Compost

Compost

Sample Preparation Sample Preparation

Water : Dry binder: Water : Dry binder: 0.6 : 1 0.6 : 1 Dry binder content by weight : Dry binder content by weight : 10%, 20% and 30% 10%, 20% and 30% Binders: Binders: either PC only either PC only or

• r 1:1 PC:other binder

1:1 PC:other binder Sample size : Sample size : 50 x 100 mm 50 x 100 mm

Testing Program Testing Program

Tests at 28 days of curing Tests at 28 days of curing

1. 1.

Unconfined compressive strength (UCS) Unconfined compressive strength (UCS)

2. 2.

Leachability Leachability (Chloride and Oil) (Chloride and Oil)

3. 3.

Leachate Leachate pH pH

4. 4.

Microstructure analysis Microstructure analysis

1.

• 1. Unconfined Compressive Strength (UCS)

Unconfined Compressive Strength (UCS)

Microsilica-PC PC BFS-PC Zeolite-PC PFA-PC MgO-Cement 2 CKD-PC Lime-PC Compost-PC MgO-Cement 1

3 0 % 20% 10%

5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 4 0 0 0 4 5 0 0

UCS (kPa)

2. 2.

Chloride Chloride Leachability

Leachability

10% 20% 30%

950 1250 1550 1850

PC PFA- PC CKD- PC Compost- PC MgOcement 1 MgOcement 2 Microsilica- PC BFS- PC Zeolite- PC Lime- PC

Chloride leachate conc. (mg/L)

2. 2.

Oil Oil Leachability

Leachability

10% 20% 30% 10 100 1000 10000 PC PFA- PC CKD- PC Compost- PC MgOcement 1 MgOcement 2 Microsilica- PC BFS- PC Zeolite- PC Lime- PC

Paraffin oil leachate conc. (mg/L)

3.

• 3. Leachate

Leachate pH pH

Binder content Binder System 10% 20% 30% PC 12.0 12.4 12.6 BFS - PC 12.0 12.2 12.4 Microsilica - PC 10.5 10.4 10.6 Compost - PC 11.6 12.1 12.2 PFA - PC 12.0 12.1 12.1 MgO cement2 10.9 12.0 12.0 12.1 9.9 11.6 Lime - PC 12.0 12.4 MgO cement1 12.5 11.0 11.9 11.0 12.3 Zeolite - PC 11.7 CKD- PC 12.4

4.

• 4. Microstructural Analysis

Microstructural Analysis

SEM at 28 days

Microsilica - PC MgO cement 2 Lime - PC Zeolite - PC Compost - PC PC

IV.

• IV. Ongoing Programme

Ongoing Programme

• North Sea Case Study

North Sea Case Study

• Best S/S systems selected for more detailed study

Best S/S systems selected for more detailed study

• Next mixes to include heavy metals

Next mixes to include heavy metals

• For chloride, possibility of a low pH cement

For chloride, possibility of a low pH cement

• Pelletisation of thermally treated drill cuttings

Pelletisation of thermally treated drill cuttings

V.

• V. Conclusion

Conclusion

• Drill cutting is a big problem that the petroleum

industry is keen to find solutions

• The utilisation of S/S techniques to treat drill cuttings

by using conventional as well as novel binders indicated the following:

• UCS of the drill cuttings

UCS of the drill cuttings-

• binder mixes at 28 days

binder mixes at 28 days covered a wide range of feasible applications. covered a wide range of feasible applications.

V.

• V. Conclusion (contd.)

Conclusion (contd.)

• Chloride leachate concentrations showed a change from

Chloride leachate concentrations showed a change from hazardous to non hazardous to non-

• reactive hazardous waste.

reactive hazardous waste.

• Oil leaching concentrations decreased as the dry binder

Oil leaching concentrations decreased as the dry binder content increased. content increased.

• The

The leachate leachate pH values indicated the use of lower pH binders. pH values indicated the use of lower pH binders.

• The

The microstructural analysis suggested an advanced level of microstructural analysis suggested an advanced level of hydration. hydration.

• Future work will give more detailed information on the

relative performance of different binders.

Thank You Thank You Thank You Thank You

Marwa Marwa at Ras Shukier oil field May 2003 at Ras Shukier oil field May 2003