Produced Water Treating NATCO Group

PRODUCED WATER TREATMENT CARACAS, VENEZUELA NOVEMBER 6-7, 2001

By: Kevin Juniel Senior Process Engineer NATCO Group Houston, TX

Outline •INTRODUCTION •WHAT IS PRODUCED WATER? •PROPERTIES OF PRODUCED WATER •ENVIRONMENTAL ISSUES •HOW IS PRODUCED WATER HANDLED? •WHY TREAT PRODUCED WATER? •WATER CHEMISTRY ISSUES •HOW TO TREAT PRODUCED WATER •SUSPENDED OIL REMOVAL •SUSPENDED SOLIDS REMOVAL •CHEMICAL TREATMENT •BACKWASH WATER TREATMENT •MATERIAL SELECTION ISSUES

•CONCLUSION

• Sources

• Formation Water • Water-flood water • Water from operations- i.e. kill fluids • Chemicals from treatment

Produced Water Sources Platform

Ocean Surface Chemicals Bottom of Ocean Subsea Safety Safety Valve

Formation Water

Seawater Injection

Oil

Injection Water

Components in Produced Water l

Water

l

Organics Salts Solids Biological Matter Added Materials

l l l l l

N ORM – Naturally Occurring Radioactive Material

Typical Composition W at er , %

90to99.9

O r g a n i c s, % Salts,ppm

0.1to0.2 100to350000

S o l i ds , pp m

10to50

Bacteria,colonies/ml

10,000

Example Produced Water -

1 0 , 00 0 B W P D

-

1 0 0 0 p p m o il o f 3 4 º A P I

-

1 0 0 p p m s o l i d s o f S G = 2. 0

-

10 ppm dissolved organics

-

50,000 ppm TDS , SG = 1.03 1 0 0 ° F @ 1 0 0 p s ig

Salinity Gulf of Mexico S e aw at er

27,000 to 44,000 mg/l mostly sodium chloride

New Mexico field 75,000 mg/l mostly magnesium sulphate

Environmental Regulations GOVERN EMISSIONS INTO WATER, AIR OR LAND (MUST HAVE UNDERSTANDING OF IMPACT ON ENVIRONMENT) l

DICTATE LEVEL OF TREATMENT FOR DISPOSAL INTO WATER BODIES (INTERNATIONAL, FEDERAL, STATE AND LOCAL) l

CHANGE IN REACTION TO DEVELOPING TECHNOLOGY (HOWEVER PRESSURE TO INSTILL TIGHTER LIMITS) l

l

NON-COMPLIANCE CAN BE DEVASTATING FOR OPERATORS

INVESTMENTS IN ENVIRONMENTAL COMPLIANCE DO NOT SHOW UP ON THE BOTTOM LINE – OR DO THEY? l

How Produced Water is Handled • Disposal (Surface, Subsurface) • Enhanced Recovery (Waterflood, Steamflood) •Agriculture (Irrigation) •Process/Plant Water •It is estimated that the produced water volume will 3-6 times the oil volume over the life of anreach oilfield

Produced Water vs. Life of Oilfield

Gas Oil y ti t n

Water

u a Q

Time

What is Water Treatment? 1.

PREPARE WATER FOR INJECTION INTO WATERFLOOD OR DISPOSAL ZONE

2.

PREPARE W ATER FOR OVERBOARD/SURFACE DISPOSAL

3.

UTILITY AT FACILITY

4.

AGRICULTURAL USE

5.

RECOVER OIL TO RE-ROUTE TO THE CASH REGISTER

Produced Water Treatment Objectives for Oilfield Use l

REDUCE SUSPENDED OIL CONCENTRATION TO COMPLIANCE LEVELS OR TO LEVELS SPECIFIED BY RESERVOIR DEPT.

l

REDUCE SUSPENDED SOLIDS CONCENTRATION TO COMPLIANCE LEVELS OR TO LEVELS SPECIFIED BY RESERVOI DEPT.

l

ADDRESS ANY WATER CHEMISTRY ISSUES (CHEMICAL INJECTION SYSTEM)

l

EXCLUDE OXYGEN FROM THE SYSTEM

l

MINIMIZE CAPITAL AND OPERATING EXPENSE (DOWNTIME)

How Clean Does The Water Need To Be? ”Typical” Waterflood • Solids < 5-10 mg/l •Oil< 5-10 mg/l • 95% removal of 5+ micron

Overboard in US GOM Oil 42 mg/l daily max., 29 mg/l monthly avg.

Water Chemistry Issues l

HIGH DISSOLVED SOLIDS CONTENT

l

HIGH SCALING TENDENCY

l

MIXING PRODUCED WATERS

l

MIXING PRODUCED WATER AND SURFACE WATER

l

CORROSION POTENTIAL/CORROSION CONTROL

l

CONTROL OF BACTERIA GROWTH (AEROBIC/ANAEROBIC)

Open System Versus Closed System Design l

ADVANTAGES OF CLOSED SYSTEM

l

ADVANTAGES OF OPEN SYSTEM

1. 2. 3.

EXCLUDE OXYGEN MINIMIZE CORROSION MINIMIZE SCALE FORMATION MINIMIZE AEROBIC BACTERIA

1.

C H E A P T O BU I L D

4.

5. 6. 7.

P RESERVE PROCESS HEAT EXCLUDE OUTSIDE CONTAMINANTS MINIMIZE EMISSIONS

REVIEW 1. WHAT IS PRODUCED WATER? 2. WHY MUST PRODUCED WATER BE TREATED? 3. HOW IM PORTANT IS P RODUCED WA TER TRE ATMENT T O AN OPERATING FACILITY? 4. WHY IS A C LOSED S YSTEM P REFERRED? 5. WHAT MU ST BE C ONSIDERED W HEN MI XING PRODUCED WATER WITH FRESH WATER? 6. HOW DO ES PRODUCED WATER TEEATMENT AFFECT PROFITABILITY? 7. WHAT ARE SOME USES OF PRODUCED WA TER IN AN OILFIELD OPERATION? 8. HOW CLEAN MUST PRODUCED WATER BE?

Process Definition Bulk oil removal

l

Free oil removal

l

Dispersed oil removal

l

Water polishing

l

Proposal / injection

l

Processes That Treat Produced Waters • Specific Gravity Differences

•Flotation •Enhanced Gravity • Physical trapping •Chemical Treatment

SUSPENDED OIL/SOLIDS SETTLING STOKES LAW

Dsg(water-oil)(d2) F V = where:

V F

V = = particle moving velocity

=force D sg= density d = droplet size m = viscosity

FACTORS AFFECTING PERFORMANCE BASED ON STOKE’S LAW 1. DROP SIZE 2. TEMPERATURE (VISCOSITY,DENSITY) 3. GRAVITATIONAL FORCE HENCE, OUR GOAL IN PROCESS SYSTEM DESIGN IS TO MAXIMIZE OR ENHANCE THE FACTORS TO PROMOTE GOOD SEPARATION. EXAMPLES…..

Bulk Oil Removal (Gravity) TECHNOLOGY

Skim Tanks Horizontal Skimmers Vertical Skimmers API Separators

PURPOSE

Mitigate flow surges Evolve entrained gas Reduce oil concentrations Provide solids settling

Horizontal Separator Oil droplets >150 microns Settleable solids >50 micron Retention time 150 microns Settleable solids >25 micron Retention time 150 microns Settleable solids >50 micron Retention time 20 + minutes

Refinery Waste Water Industrial Waste Water

API Separator Options l

l

Inlet Distribution Headers for Flow Control Solids Hopper for Solids Collection

l

Flight and Rake System for Solids/Oil Removal

l

Adjustable Rotating Pipe Skimmer for Oil Removal

l

Rotating Drum Skimmer for Enhanced Oil Removal

l

Corrugated Plate Pack for 50 Micron Oil Droplet Removal Efficiency

Free Oil Removal TECHNOLOGY

PURPOSE

Corrugated Plate Interceptors (Upflow or Downflow ) Matrix PlateSeparators Liquid/Liquid Hydrocyclones

Primary separation of oil from water

Solid/Liquid Hydrocyclones Primary separation of oil free solids from water

Down Flow CPI Oil Removal (Gravity)

l

Plates at 45º Angle

l

Plate spacing 18mm

l

Plate pack material is

l

316SS or FRP

Coalescing Plate

Up Flow CPI Solids Removal (Gravity)

l

l

Plates at 60º Angle Plate spacing 25mm

l

Plate pack material is

l

316SS or FRP

Matrix Plate Separators (Gravity) Oil droplets d90 @ 50 micron Settleable solids d50 @ 25 micron Velocity 1–3 ft/min

Onshore / Offshore Production Minimal Surge Protection Insensitive to Pitch / Roll

REVIEW 1. DESCRIBE STOKE’S LAW? 2. WHAT ARE COMMON WATER TREATING PROCESSES THAT ARE BASED ON STOKE’S LAW? 3. HOW DO ES THE S IZE OF T HE O IL DROPLET AFFECT THE PERFORMANCE OF OIL REMOVAL EQUIPMENT? 4. WHICH OIL WILL PERFORM BETTER – 16 API OR 34 API? WHY? 5. HOW DO PLATE SEPARATORS WORK? 6. WHICH ORIENTATION IS BETTER FOR SEPARATION – HORIZONTAL OR VERTICAL? 7. WHICH ORIENTATION IS LESS SENSITIVE TO MOTION – HORIZONTAL OR VERTICAL? 8. WHAT IS THE ADVANTAGE OF ADDING MATRIX PACKING TO A SKIMMER OR SEPARATOR VESSEL? WHAT ARE POTENTIAL DISADVANTAGES OF THIS TYPE OF INTERNALS?

Liquid/Liquid Hydrocyclones

Enhanced Gravity Convert Pressure Energy to Centrifugal Energy Insensitive to Motion or Surges No Chemicals or Power (if high enough pressure) Small Oily Reject Stream (2% of Inlet Flow)

Liquid/Liquid Hydrocyclones

Operating Principles l l l l

Internal geometry creates a vortex (inlet,taper) Centrifugal force accelerates separation Oil droplets separate and coalesce in the center Oil is funnelled into the overflow for removal

PRINCIPLE OF OPERATION

L/L Hydrocyclones l

l l l l

Developed, proven technology High efficiency Flexible, Easy to Expand Compact Design Lightweight

L/L Hydrocyclone Vessel Liner Bundle

l l

Easy to Install for Future Expansion Individually Accessible

Liner Design l

Corrosion resistant liner Oilspin AVh

l

material Erosion resistant liner material

l

Ease of operation

l

No moving parts

l

Low maintenance

Oilspin AV

Oilspin AVi

“Typical” Performance Corrected Efficiency

1.00 0.90 0.80 l a 0.70 v o m e r 0.60 f o 0.50 y ti li b 0.40 a b o r 0.30 P

0.20

LQ AV"dev 2"

0.10 0.00 0.0

5.0

10.0

15.0 20.0 25.0 Droplet daimeter, micron

30.0

35.0

Produced Water Treatment Fuel Gas Supply From HP Separator

Liquid/Liquid Hydrocyclone

PVC

LC

PV

Degasser From LP Separator

LC

PC

To Hazardous Drain

PV

LP Sep From Test Separator

Flowmeter

Discharge LVC

PV

Reject to LP Separator

L/L Hydrocyclone Construction Efficiency equal to or better

l

than all competing hydrocyclones lInternal geometry and Stellite inlet reduce erosion Cones : duplex SS Tails:

l

Sanicro 28 Easily installed and removed -

l

no special tools required

Installation

BP GEISUM PLATFORM NORTH SEA

PRODUCED WATER 23,000 BWPD

OILSPIN AVi INSTALLATION DESIGN •MINIMIZE SPACE •MINIMIZE INSTRUMENTS •INCREASE OPERATING FLEXIBILITY •OVERALL REDUCTION IN COST •MAINTAINING HIGHEST EFFICIENCY

OILSPIN AVi -

UNLIMITED TURNDOWN!!!

Oilspin AVi Interactive Hydrocyclone Method of operation - on line

Oilspin AVi Interactive Hydrocyclone Method of operation - off line

Oilspin AVi Interactive Hydrocyclone Method of operation - on line

Oilspin AVi Interactive Hydrocyclone Hydrocyclones switched

l

individually or in groups

H. P. SOURCE

2 years operating

l

experience on Tyra East Ideal for test

l

separators,

frequently changing systems or difficult separations L. P. DRAIN

Oilspin AVi Interactive Hydrocyclone Eliminates need for

l

multiple or compartmented vessels

H. P. SOURCE

Fully automatic hydraulic

l

operation New manual activation

l

system under development.

L. P. DRAIN

SUSPENDED SOLIDS REMOVAL SOLID/LIQUID HYDROCYCLONES TYPICAL APPLICATIONS

PRODUCED WATER DESANDING WELLHEAD DESANDING FILTER PRE-TREATMENT SAND WASHING

Hydrocyclone Design

•MULTI LINER VESSEL •D95 >15 MICRONS •VARIOUS DUMP OPTIONS •CERAMIC LINERS AVAILABLE

Large Diameter Range

15” 12”

9”

Small Diameter Range

1” Canned 1” Vessel 1” Cutaway 2”Canne d 2”Vessel

12 mm Desanders l l

l l

d90 5 to 7 microns Flowrate typically below 0.1 m3/h so huge numbers required Very prone to blockage Upstream strainers or desanders required for protection

Ceramic Desanders l

Default 3” ceramic desander

l

Flowrate/efficiency modified by vortex finder selection Capacity 10 to 30 m3/h each Potted underflow or continuous (>2%) d90 15 to 50 microns 2” and 1” also available taking d90 down to 11 microns

l

l

l l

Performance Range

Solid/Liquid Hydrocyclone Installation Gamra, Libya Well-head Desanders l

l

3,700,000 bpd

l

90 off 15 PHQ

95% removal > 100 microns l

l

Aquifer water

Solid/Liquid Hydrocyclone Installation l

Al Furat Petroleum

l

Omar Phase II Field, Syria

l

110,000 bpd

l

13 off 10 PHQ

l

95% removal > 40 microns

l

River water

Mounting arrangements

Solid/Liquid Hydrocyclone Installation l

Anadarko/Sonatrach

l

Algeria HBNS Development

l

10 Micron Separation

l l

l

150,000 bwpd Aquifer Wate r 306 off 2CLQ

Solid/Liquid Hydrocyclone Installation l l l

l l

Maersk Petroleum Qatar Al-Shaheen Field Development 98% > 10 micron rating

l

75,000 BWPD Produced water

l

146 off 2PHQ

l

l l

Used in conjunction with Oilspin AV LLC’s

High Pressure Wellhead Desander

l

l l

l

Halliburton for PDO Welltesting Operations Designed to separate solids from multi-phase fluids Welltesting and clean up First fully coded ASME VIII Division 2 hydrocyclone vessel supplied globally 3” x 7 way, 10,000 psi unit

Wellhead Desander Shell/PDO Marmul Field l

l

l l

l

Compact with high throughput Ultra high erosion resistance No backflushing Reduced weight & size compared with conventional filters Continuous or batch operation

Wellhead Desander l l

l

l l

l

Wide operational envelope Maintains separation during slugging, rates, very high varying GLR andflow varying phase composition Gas/liquid ratios between 5 and 100 possible Higher pressure, higher GLR Pressure drop 1-15 bar depending on application High erosion resistance due to inlet geometry and materials

Sandwash System l

Designed to separate and remove oil contaminated solids to produce oil free sand (