Water Technologies

Walnut Shell Filters

Siemens Water Technologies

Redesigning for Offshore Use

Michael Howdeshell

Chad Felch

Eric Lorge

Slid

e2

Water Technologies

Geography

-Siemens

-O&G offices

Slid

e3

Water Technologies

Agenda

Walnut Shell Technology Background

Testing in North Sea

Taking Walnut Shell Technology Off-Shore

Slid

e4

Water Technologies

ProducedWater

Water Treatment in Oil Field Industry

Tertiary Separation

Walnut shell filter

Coalescing filter

Cartridge filter

Sand filter

Secondary Separation

Dissolved Air Flotation (DAF)

Dissolved Gas Flotation (DGF)

Induced Gas Flotation (IGF)

Primary Separation

Hydrocyclone

API Separator

Plate Separator

Skimmer

Slid

e5

Water Technologies

Separation Technology Spectrum

10,0001,000100101

Oil in Water Concentration (ppm)

Eff

icie

ncy

API

CPI

DAF, IGF, DGF

Hydrocyclone

Centrifuge

Membrane

Walnut Shell and

Coalescing Filters

1º

2º

3º

Slid

e6

Water Technologies

How Do Walnut Shell Filters Work

Continuous pressurized media bed

Bed(s) cycle based on time or ΔP

Media is recharged using backwash cycles

Oil is adsorbed not absorbed

Used to removed SS and free oil

Walnut shell media have an equal affinity for oil and water

Very low attrition rate

Slid

e7

Water Technologies

The Siemens Walnut Shell Filter Media

The Black Walnut Shell

Excellent surface characteristics for

Coalescence

Filtration

High “modulus of elasticity”

Chemical free oil separation

Slid

e8

Water Technologies

Walnut Shell Global Usage

- Installation

- Void regions

Slid

e9

Water Technologies

Pilot Testing – BP Valhall Platform

Objectives

Prove walnut shell media can handle North Sea produced water

Test efficiency of system

Suitable for off-shore?

Stavanger

Bergen

Oslo

BP Valhall

Slid

e10

Water Technologies

Pilot Unit Used on BP Valhall Platform

Slid

e11

Water Technologies

Walnut Shell Media Close-ups

Slid

e12

Water Technologies

Backwash Procedure Used in Test

Slid

e13

Water Technologies

Results from Pilot Testing

*

* Measurements conducted with TD500 OiW analyzer

Slid

e14

Water Technologies

Results from Pilot Testing –

Inlet and Effluent Oil Concentrations

45

50

55

60

65

70

8/21/2008 8/22/2008 8/23/2008 8/24/2008 8/25/2008 8/26/2008

Inle

t o

il (

pp

m)

0

1

2

3

4

5

Eff

lue

nt

oil

(p

pm

)

Slid

e15

Water Technologies

Results from Pilot Testing –

Oil Removal Efficiency

80

82

84

86

88

90

92

94

96

98

100

8/22/2008 8/23/2008 8/24/2008 8/25/2008

Slid

e16

Water Technologies

Moving from On-Shore to Off-Shore

Demonstration Objectives

Prove walnut shell media can handle North Sea produced water

Test efficiency of system

Suitable for off-shore use?

Off-shore challenges

Footprint and weight reduction

Simplify and optimize backwash system

Slid

e17

Water Technologies

Moving from On-Shore to Off-Shore

Tasks

Reduce external scrubbing

Increase throughput

Reduce backwash water volume

Slid

e18

Water Technologies

Siemens Internal Backwash

Slid

e19

Water Technologies

Improvements for Off-Shore

Complete turn over and mixing of the media

Fully fluidize the walnut shell bed

No rotating equipment or moving parts

The ability to use a finer walnut shell media to improve oil and solids removal

Smaller footprint and weight

A reduction in backwash water volume

0.72%0.35%

5%

Sand Filter Old WSF New WSF

Fo

rwa

rd F

low

Us

ed

fo

r

Ba

ck

wa

sh

(%

)

Slid

e20

Water Technologies

The Siemens Walnut Shell Filter

Design Considerations

Ready for off-shore use

Refinement of the design through many years of successfully commissioned installations, most of which still in operation today

Direct experience of many applications for which walnut shell filters can be appropriate

No compromise of design to ensure effluent quality is maintained

Slid

e21

Water Technologies

Summary

Walnut Shell Media

Efficiently remove oil from North Sea produced water

Solids do not impact the efficiency

Suitable for off-shore use

Walnut Shell System

Reduced footprint through efficient backwash design and finer shell media

Reduced weight

Reduced backwash water volume

Slid

e22

Water Technologies

Thank you for your attention!