Application of Nanofiltration and Reverse Osmosis Membranes for Produced Water Treatment

Application of Nanofiltration and Reverse Osmosis Membranes for Produced

Water Treatment

Arun Subramani Ron Schlicher Jim Long Jack Yu Geno Lehman Joseph Jacangelo

MWH Americas Inc

618 Michillinda Avenue Suite 200

Arcadia California 91007

ABSTRACT

Produced water is a term used to describe water that is obtained along with oil and gas

production Produced water constitutes the single largest waste stream from oil and gas

exploration and production activities and contains high levels of oil and grease total dissolved

solids (usually sodium chloride) hydrocarbons and refractory organics If treated appropriately

produced water can be employed as a true water resource to augment existing surface water

streams and creeks Due to stringent surface discharge limits being imposed in the United States

produced water needs to be managed and treated before being discharged to surface water

streams and creeks Certain discharge limits require a chloride concentration of less than 230

mgL in the treated water Treatment of such wastewater streams to meet low chloride selenium

and boron discharge limits requires a technology such as nanofiltration (NF) and reverse

osmosis (RO) which can serve as an absolute barrier for various contaminants In this study

different types and configurations of NF and RO processes were pilot tested to determine their

applicability in treating produced water obtained from natural gas wells at a location in the

western United States In order to reduce the fouling potential on NF and RO membranes

dissolved air floatation (DAF) ceramic ultrafiltration (UF) MYCELX cartridges and

organoclay filters were tested as pretreatment alternatives It was determined that the fouling

potential of NF and RO membrane was not substantially different for the various pretreatment

processes utilized In order to handle high silica concentrations in the feed water and increase the

overall feed water recovery a two pass NF-RO system was tested The first pass NF system was

used to remove hardness and alkalinity from the feed water The pH of permeate from the first

pass NF system was increased to 100 to increase silica solubility and used as feed to a second

pass seawater RO system A combination of spiral wound and disc tube configuration was

effective in achieving more than 90 percent recovery for the first pass NF membranes while an

overall feed water recovery of more than 70 percent was achieved for the entire NF-RO

membrane system and also resulted in meeting the discharge limits

KEYWORDS Oily wastewater silica polymerization organic fouling recovery optimization

491

Membrane Applications 2010

Copyright copy2010 Water Environment Federation All Rights Reserved

INTRODUCTION

Produced water water that is co-produced during oil and gas extraction represents the largest

source of oily wastewaters (Mueller et al 1997) The volume of produced water can be as much

as ten times the volume of oil extracted (Mondal and Wickramasinghe 2008) Produced water

consists of a combination of organic and inorganic compounds and production chemicals

Typical organic compounds present are aliphatic aromatic and polar compounds Inorganic

components include sodium potassium calcium magnesium chloride sulfate carbonate

silicates and borates Production chemicals can include emulsion breakers to improve separation

of oil and water and corrosion inhibitors (Mondal and Wickramasinghe 2008) The

concentration of these contaminants can vary significantly due to natural variation in the

geological formation and the type of oil-based product being produced (Franks et al 2009)

The typical method of dealing with produced water is deep well injection A portion of the

produced water is reinjected into oil producing zones to improve oil recovery through water or

steam flooding (Visvanathan et al 2000) The other portion of produced water is disposed off

through deep well injection Deep well injection is limited by the capacity of the injection wells

and discharge limits set by local governing agencies Due to this limitation in discharging the

produced water oil production companies are looking into options for treating the produced

water for surface discharge Example of discharge limits based on the class and purpose is listed

in Table 1 Certain discharge limits (Class 2AB) require a chloride concentration of less than 230

mgL in the treated water Treatment of such wastewater streams to meet low chloride and boron

discharge limits requires a technology such as NF and RO which can serve as an absolute

barrier for various contaminants The use of membrane technology also offers other advantages

such as a smaller footprint high level of automation and applicable for both onshore and

offshore oil exploration (Mondal and Wickramasinghe 2008)

Table 1 Example of surface water discharge limits for produced water

OBJECTIVES

Although high-pressure membrane processes such as NF and RO have been used in the past for

produced water treatment (Bartels and Dyke 1990 Tao et al 1993 Mohammadi et al 2003

Franks et al 2009) limited studies are available which have looked into the application of

advanced pretreatment technologies for controlling fouling and recovery optimization for NF and

Class Purpose Discharge limit

3D Beneficial use for livestock watering TDS lt 5000 mgL Oil and grease lt 10 mgL

65 lt pH lt 9 Turbidity lt 10 NTU Chloride lt 2000 mgL Boron lt 5 mgL

3B Aquatic life ephemeral streams TDS lt 5000 mgL Oil and Grease lt 10 mgL

65 lt pH lt 9 Turbidity lt 10 NTU BOD5 lt 30 mgL

TSS lt 30 mgL Cadmium lt 054 ugL Selenium lt 5 ugL

Sulfur lt 2 ugL Chloride lt 2000 mgL Boron lt 5 mgL

2AB Potable water preserving fish life TDS lt 5000 mgL Oil and Grease lt 10 mgL



Sulfur lt 2 ugL Chloride lt 230 mgL Boron lt 5 mgL Benzene lt 22 ugL

Toluene lt 1 mgL Ethylbenzene lt053 mgL

492



RO processes In this study pilot-scale evaluation of pretreatment using ceramic ultrafiltration

MYCELX filtration DAF and organoclay filtration were performed and recovery optimization

of NF and RO process was conducted for produced water obtained from natural gas wells at a

location in the Western United States Given the range of discharge standards the pilot system

was designed to provide recommendations on meeting the most stringent case (which includes a

chloride limit of 230 mgL) Specific objectives of the study were as follows

bull Assess the applicability and performance of DAF organoclay filtration MYCELX

filtration and ceramic ultrafiltration as pretreatment ahead of NF and RO membrane

system to minimize fouling

bull Evaluate the performance of NF and RO membranes with different operating

configurations (ie double pass systems and multistage systems) to maximize water

recovery

MATERIALS AND METHODS

Three different treatment schemes were tested at the pilot-scale A schematic of the treatment

scheme is shown in Figure 1 The three different treatment schemes were tested one at a time

The first pretreatment scheme was DAF Ceramic UF The second pretreatment scheme was

DAF Organoclay The third pretreatment scheme was DAF MYCELX filtration

Figure 1 Treatment schemes used at the pilot-scale

Caustic1

3

2

DAF

UF

Organoclay

MYCELX

Spiral NF

DT NF

Spiral RO

Treated Water

Reject Water

Permeate

Concentrate

493



Dissolved Air Floatation

Produced water from natural gas wells were first treated in gun barrel tanks for oil and water

separation After the gun barrel tanks the produced water was fed to a DAF system (VanAire

Inc) The DAF system was used for further reduction of oil and grease and turbidity of the

produced water A hydraulic retention time of 60 to 90 minutes was used in the DAF A 50

recycle of feed and an air flow of 1 standard cubic feet per hour were used during testing To

enhance flocculation and settling 1 to 3 mgL of polymer and 50 to 100 mgL of aluminum

chlorohydrate (Baker Petrolite Chemicals) was tested in the DAF system

Ceramic Ultrafiltration

The first prettreatment scheme used was ceramic ultrafiltration A ceramic UF system

(Membralox Unit X15) was leased from PALL Water Processing (New York USA) A

schematic of the ceramic UF membrane element and structure is shown in Figure 2 The UF

system consisted of seven ceramic elements with a total membrane area of 25 m2 A 50 nm

alumina-zirconia type of ceramic filtration membrane was used for the study Ceramic

membranes have several advantages over polymeric membranes such as higher flux (up to 5

times higher) higher operating temperature (up to 95 0C) and pressure (up to 150 psi) longer

membrane life (up to 5 years) resistance to harsh chemical cleaning and full pH compatibility

A range of crossflow velocities (30 to 45 msec) transmembrane fluxes (100 to 150 gfd) feed

water recoveries (75 to 90 percent) and backpulse intervals (3 to 5 minutes) were evaluated

Figure 2 Schematic of ceramic membrane module and filtration layer (Source PALL

Corporation)

494



Organoclay Filtration

The second pretreatment scheme utilized was organoclay filtration Organoclay was obtained

from Aquatech Inc Wyoming Organoclay are chemically altered volcanic ash consisting of

montmorillonite They have a surface area of approximately 750 m2gm and used for the removal

of oil and grease turbidity metals and solvents An organoclay filtration bed with an empty bed

contact time (EBCT) of 15 minutes was used to the study Backwashing was performed when the

pressure drop across the bed exceeded 30 psi

MYCELX Filtration

The third pretreatment scheme utilized was MYCELX filters obtained from Mycelx

Technologies Inc Georgia MYCELX technology was used as an alternative to organoclay

filtration for the removal of oil and grease MYCELX filters are considered to be effective in the

removal of hydrocarbons oil sheen synthetic oil and natural oil In this study 25 micron filters

arranged in series were used Effluent from the DAF was used as the feed to the MYCELX

filters The filters were coated with polymeric surfactant technology to enable the removal oil

droplets

NF and RO Membranes

High-pressure membranes were used for reduction of TDS and target constituents such as

chloride boron and selenium Two types of NF and one type of RO membrane was used The

NF membranes used were NF270 (DowFilmtec) and NF90 (DowFilmtec) The RO membrane

used was TM810L (Toray) The NF270 membrane is considered to be a ldquolooserdquo nanofiltration

membrane with 40-60 rejection of CaCl2 and less than 35 rejection of NaCl In contrast the

NF90 membrane is considered a ldquotightrdquo nanofiltration membrane and has more than 85

rejection of NaCl The TM810L membrane is used for seawater desalination and is a cross linker

fully aromatic polyamide composite membrane and has more than 9975 rejection of NaCl

Disc Tube Technology

A DT system was leased from PALL Water Processing (New York USA) An image of the

DT system module is shown in Figure 3 The DT system consists of commercial flat sheet

membranes installed in a plate and frame configuration The length of the module is 1 m (33 ft)

and the membrane area in the module is 765 m2 (823 ft2) The module consists of a fiber glass

housing and can withstand pressures up to 1000 psi The module consists of unique crossflow

construction with stacked membrane discs The disc membrane stack was housed in an 8-inch

(diameter) pressure vessel and assembled on a center tension rod using stainless steel end

flanges The extremely short feed water path across the membrane surface followed by a 180o

flow reversal greatly reduces concentration polarization on the membrane surface reducing

fouling and scaling potential The DT module is capable of operating at high particulate loading

(2500 mgL) The system was operated at various recoveries (50 - 85) Flux was maintained

constant (18-20 gfd) for all the tests To minimize the scaling potential due to sparingly soluble

salts 8 mgL of MDC150 ( 3617 Eastern Technologies Inc) antiscalant was added to the

system

495



Figure 3 Illustration of DT module (Source PALL Corporation)

Spiral Wound Technology

A spiral wound (SW) RO skid was leased from PALL Water Processing (New York USA) and

used for pilot testing In a SW system the membrane is wound on a central tube in a spiral

configuration Membrane leaves are separated by a feed spacer used to promote turbulence and

reduce concentration polarization A permeate spacer transports the permeate water to the center

tube The concentrate stream leaves the element to be further treated by another SW membrane

element or discharged The SW system consisted of 8 pressure vessels which could be

configured as 8 SW elements connected in series Each pressure vessel accommodated a SW

membrane element with nominal dimensions of 4rdquo x 40rdquo The system was also configured as 4

SW elements connected in series with a fraction of the concentrate stream recycled back to the

feed of the first SW element For the first pass testing NF270 membranes were installed in the

SW system For the second pass testing TM810L membranes were used The system was

operated at various recoveries (50 - 75 for first pass and 50 ndash 80 for second pass) Flux was

maintained constant (less than 10 gfd) for all the tests To minimize the scaling potential due to

sparingly soluble salts 8 mgL of MDC150 ( 3617 Eastern Technologies Inc) antiscalant was

added to the system for the first pass Before the second pass tests pH of the water was raised to

100 by addition of sodium hydroxide to increase the solubility of silica (Sheikholeslami and

Tan 1999) To further minimize silica scaling on the second pass membranes an antiscalant

specific to silica (Formula 3680 Eastern Technologies Inc) with a dosage of 8 mgL was used

Chemical cleaning of the membrane systems were performed with cleaning chemicals provided

by PALL Water Processing (New York USA) Low pH cleaning solution used was RO

Cleaner C which was composed of 10 ndash 30 citric acid The high pH cleaning solution used was

RO Cleaner A which was composed of 0 -5 sodium hydroxide and 0 ndash 5 ethylene diamine

tetra acetic acid Cleaning was performed with a low pH solution (pH~20) followed by use of

high pH solution (pH ~110) Each cleaning cycle was performed for a period of 2 hours at with

clean water flush in between cleaning cycles For high pH cleaning of NF membranes special

cleaning solution (Cleaner NFE) was used High pH cleaning for NF membranes was performed

496



at pH ~90 All chemical cleanings in the DT system was performed at room temperature

Chemical cleaning in the SW system was performed at 40 deg C

RESULTS

Feed Water Quality

Average feed water quality to the pilot plant is listed in Table 2 The contaminants included

suspended solids oil and grease dissolved organics volatile organic compounds metals soluble

salt The pH of the produced water was approximately 75 The concentration of gasoline range

organics (GRO) was substantially higher than diesel range organics (DRO) The 5-day biological

oxygen demand (BOD5) and chemical oxygen demand (COD) were also high in the feed water

The temperature of the produced water was as high as 80 0C Since the operation of NF and RO

membranes is limited to less than 40 0C a heat exchanger was installed to cool the influent feed

water to the pilot plant The concentration of silica varied between 60 and 100 mgL in the feed

water Operating the RO process at 50 recovery with a feed water silica concentration of 100

mgL would result in 200 mgL of silica in the concentrate stream (concentration factor of 2)

exceeding the solubility limit of silica

Table 2 Average feed water quality to the pilot plant

The presence of suspended solids oil and grease in the feed water can severely hinder the

performance of NF and RO process due to fouling Thus several pretreatment techniques were

Parameter Concentration (mgL)

Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75

Alkalinity as CaCO3 2690

Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497



evaluated for the removal of suspended solids and oil and grease The performance of different

pretreatment processes evaluated is described below

Performance of DAF

For enhanced flocculation and settling of suspended particles hydrocarbons and oil and grease

chemicals were added to the feed water of the DAF Optimum chemical dosage was determined

through jar testing During pilot testing turbidity removal between 60 and 90 was achieved

consistently in the DAF system The percentage removal of oil and grease varied between 25 and

90 This is attributed to significant variation in the oil and grease content of the feed water An

increase in the chemical dosage to the DAF was necessary to achieve higher turbidity removal

Although automated chemical injection system with feed-back control was not tested at the pilot

scale flow-paced chemical injection is recommended to automatically vary the dosage of

chemicals in order to deal with the feed water quality changes Overall the DAF system was

efficient as the first stage of pretreatment in reducing the concentration of oil and grease and

suspended solids Thus for all further testing the DAF system was used as the default

pretreatment step followed by either organoclay (or) MYCELX filters (or) ceramic UF

Performance of Organoclay Filtration

Organoclay filters have been used commercially for many years to remove oil from wastewaters

Column bench-scale testing results conducted using the clay showed good removal of oil and

grease as long as adequate contact time was allowed However the bench-scale tests were not

able to adequately determine the capacity of the organoclay for the oil and grease constituents

during pilot-scale testing Therefore a unit was pilot tested For the pilot test DAF effluent was

fed to the organoclay filter which operated as a down flow pressure filter As solids built up in

the organoclay media the differential pressure increased and the unit was backwashed When the

system was operated at a high hydraulic loading rate backwashing was necessary almost every

day Later in the pilot study the unit was operated at a much lower hydraulic loading rate (1

gpmsq ft) which alleviated some of the operational problems But the system achieved only 30

to 45 of oil and grease removal based on the field measurements During the initial period

when the filter was hydraulically overloaded the EBCT which is a measure of the time that

contaminants have to adsorb to the media was only 3 to 5 minutes Even after increasing the

EBCT to 15 minutes the oil and grease removal did not improve Overall the relatively poor

performance of the organoclay filter may be due to the fact that the constituents being measured

as oil and grease were not really oil and were dissolved or liquefied at the elevated temperature

of the water

Performance of MYCELX Filtration

MYCELX filters were evaluated as an alternative to the organoclay filter for oil and grease

removal Bench-scale results indicated that the filters can effectively remove oil and grease at the

ambient temperature of the laboratory The test showed an oil and grease reduction from 74

mgL down to 9 mgL after passing through two filters in series and down to 5 mgL after

passing through a third filter Based on these results MYCELX cartridge filters and snippets

were shipped to the site for pilot testing The arrangement for testing these filters at the pilot site

498



involved routing the DAF effluent through a bag filter filled with snippets and then through two

25 micron MYCELX cartridge filters in series Even with the DAF achieving good turbidity

removal the first MYCELX cartridge filter plugged within one day of operation In terms of

performance for oil and grease removal the MYCELX filter did not perform as well as expected

based from the bench-scale testing Only 18 removal of oil and grease from field

measurements was achieved It is also possible that the filters might perform better after the

water was cooled down and the oil and grease material precipitates out of solution The bench

testing was conducted at 65degF whereas the temperature of the water during the pilot operation

was around 83degF Based on the limited testing the use of MYCELX filters was recommended

only as a polishing step

Performance of Ceramic UF

As with the organoclay and MYCELX filters oil and grease removal through the ceramic UF

was much lower than expected averaging only 25 removal based on field measured oil and

grease measurements The low oil and grease reduction by the ceramic UF was likely associated

with the dissolved or liquefied organics in the water because solids and oil particles should not

pass through the small 50 nm pores of the ceramic UF Performance of the ceramic UF is shown

in Figure 4 During startup a water recovery of 80 was achievable without observing any

decline in the water flux For the first 100 hours of operation no substantial decrease in the

specific flux was observed After the initial operation period the specific flux decreased steeply

requiring chemical cleaning of the membrane to restore the specific flux to initial values

Recoveries greater than 80 lead to steep decline in the specific flux A flux decline of about

14 was observed during 550 hours of operation A three step cleaning of the ceramic UF

involved bleach and caustic soda in the first step an alkaline cleaner in the second step and

nitric acid in the third step Cleaning at elevated temperature (140degF) was found to be more

effective than cleaning at ambient temperature

499



Figure 4 Performance of ceramic UF

Limiting Recovery of RO Process

To determine the maximum recovery possible in a single pass tests were conducted using a tight

NF membrane (NF90) The NF90 membrane is capable of achieving more than 85 rejection of

salts such as NaCl Hence the NF90 membrane installed in the DT system was tested to

determine if the discharge limits can be met in a single pass and also determine the maximum

achievable recovery and fouling potential Since the fouling potential of pretreated water was no

known the DT system was utilized for estimating the limiting recovery As mentioned earlier

the DT system is capable of handling fouling prone feed water The temperature corrected flux

recovery and temperature corrected specific flux for DT system with NF90 membranes is shown

in Figure 5 Pretreatment consisted of DAF and ceramic UF membranes The recovery of the

system was increased from an initial value of 45 up to a final recovery of about 65 The

operational flux was maintained constant at 20 gfd At a recovery of less than 50 no

substantial decrease in specific flux was observed But as the recovery was increased further

(more than 55) a gradual decrease in the specific flux was observed At a recovery of 65 the

specific flux was found to be 0060 gfdpsi compared to the initial specific flux of 0085 gfdpsi

Hence within 120 hours of operation a decrease of more than 25 in the specific flux was

observed suggesting that foulingscaling of the membrane occurred leading to decrease in

performance During the entire duration of operation no substantial increase in the differential

pressure across the module was observed At the end of operation chemical cleaning was

performed to determine if the specific flux could be recovered to initial values Even after

60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi

Time of Operation hr

Specific flux 25 deg C

Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500



cleaning with both low pH and high pH solutions the specific flux was not recovered to initial

values suggesting irreversible foulingscaling has occurred on the membrane surface

Figure 5 Performance of NF90 membrane

Silica rejection was more than 90 by the NF90 membrane During the testing of NF90 silica

concentrations in the feed were between 90-100 mgL Hence with more than 90 rejection of

silica by the membrane the concentration of silica in the concentrate stream of the NF90

membrane would be over 245 mgL (concentration factor of 272 at a recovery of 65)

exceeding the silica solubility limits Although a silica specific antiscalant at a dosage of 8 mgL

was used as pretreatment for the NF90 membrane the irrecoverable specific flux after chemical

cleaning suggested that a hard silica scale had formed on the membrane surface Also

antiscalants are not efficient when silica concentrations exceed more than 200 mgL in the

concentrate stream of membrane systems Hence due to high silica concentration in the feed

water the overall feed water recovery of the NF90 membrane system was restricted to less than

65

Since silica scaling of the membrane was restricting the overall feed water recovery of the

membrane process further membrane tests were conducted to increase the silica solubility limit

in the feed water by increasing the pH of the solution In order to increase the pH of the solution

hardness related to calcium needed to be reduced to prevent the precipitation of calcium

carbonate (CaCO3) Hence a two pass membrane system was implemented In the two pass

system the permeate from the first pass is used as feed to the second pass membrane In the first

pass a loose NF membrane (NF270) was employed to remove hardness and alkalinity so that pH

can be raised to 100 in the second pass utilizing a RO membrane

0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000

Specific Flux 25 deg C gfdpsi

Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C

Specific Flux 25 deg C

501



Performance of First Pass NF Membranes

For the first pass NF270 membranes installed in SW configuration were evaluated The

temperature corrected flux recovery and temperature corrected specific flux for spiral wound

system with NF270 membranes used for the first pass is shown in Figure 6 The performance

parameters for the tests are listed in Table 3 The system was operated with different

pretreatment schemes From 0 ndash 90 hours (region 1 in the plot) the SW-NF270 membrane

system was operated with pretreated water obtained from the DAFCeramic UF system From

90 ndash 135 hours (region 2) the system was operated with pretreated water obtained from the

DAFOrganoclay filter From 135 ndash 157 hours (region 3) the system was operated with

pretreated water obtained from the DAFMYCELX cartridges From 157 ndash 204 hours (region

4) the system was operated with pretreated water from DAF Organoclay filter For the first

140 hours of operation the feed water recovery was maintained at 65 and hence the fouling

potential of different pretreatments (ceramic UF MYCELX and Organoclay) on the SW-NF270

membrane could be compared Although the specific flux seemed to fluctuate within the first 140

hours of operation there was no substantial difference in the rate of decrease in the specific flux

for the membrane when operated with three different pretreated waters Hence it is not possible

to conclusively determine the best pretreatment process for the spiral NF270 membrane with

respect to fouling After the initial tests feed water after DAF Organoclay filter was used to

obtain performance data at higher recoveries Hence the recovery of the system was increased to

70 and 75 from 140 ndash 200 hours of operation When the recovery was increased a gradual

decrease in the specific flux was observed Within 60 hours of operation at recovery greater than

70 the specific flux decreased from 015 gfdpsi to 013 gfdpsi signifying a 13 decrease

Hence membrane fouling occured when the recovery of the system was increased higher than

70 During the entire duration of operation the differential pressure across the module

increased from 20 psi to 27 psi No chemical cleaning cycles were performed for the SW-NF270

membrane system

502



Figure 6 Performance of SW-NF270 membrane

Note

1 Pretreatment is DAFCeramic UF 2 Pretreatment is DAFOrganoClay 3 Pretreatment is

DAFMYCELX 4 Pretreatment is DAFOrganoClay

Table 3 Performance parameters for SW-NF270 tests

To determine the rejection capability of the first pass SW-NF270 membrane and its applicability

as first pass membrane system water quality parameters were monitored during operation The

rejection of BOD-5 COD TDS and alkalinity was low The rejection of BOD-5 and COD was

approximately 35 and the rejection of TDS and alkalinity was less than 15 Among the

individual ion rejections the rejection of calcium was approximately 10 and rejection of

magnesium was more than 40 The rejection of chloride was negligible The rejection of

sodium was also low (less than 15) The rejection of sulfate was greater than 85 and the

Ammonia-N was rejected less than 5 The rejection of barium was about 30 where as

01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4

Test Specific Flux (Start) Specific Flux (End) Net Operating Pressure (Start) Net Operating Pressure (End)

gfdpsi 25 deg C gfdpsi 25 deg C psi psi

1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503



selenium rejection was approximately 5 Rejection of boron and selenium were low (less than

10)

In order to increase the feed water recovery of the first pass a DT-NF270 system was used to

treat the concentrate obtained from the SW-NF270 The system was operated for a total duration

of approximately 100 hours after The recovery of the system was maintained at about 71 The

flux was maintained constant at about 10 gfd The initial specific flux of the system was

determined to be ~ 052 gfdpsi The specific flux decreased to 026 gfdpsi a 50 decrease in

24 hours Although the specific flux decreased substantially within the first 24 hours of

operation it was recovered to initial value by flushing only with RO permeate The recovery of

specific flux suggested that the foulant layer deposited on the membrane surface was not

irreversibly adhered and was loosely deposited on the membrane surface During the entire

duration of operation the differential pressure across the module was constant and did not

increase No chemical cleaning cycles were performed for the DT-NF270 membrane system

while treating the SW-NF270 concentrate stream only flush with RO permeate was performed

Performance of Second Pass RO Membranes

The second pass membrane system consisted of a seawater RO membrane TM810L The second

pass membrane system consisted of the spiral wound configuration operated at a recovery of 70

ndash 80 The operating flux was maintained constant at less than 10 gfd The pH of the feed water

was increased to 100 for the second pass membrane operation to increase the solubility of silica

Temperature corrected flux recovery and temperature corrected specific flux for SW system

with TM810L membranes used for the second pass is shown in Figure 7 The system was

operated in 4 different batches since the permeate water from the first pass (SW-NF270)

membrane needed to be stored and pH adjusted The four batches of operation presented in

Figure 7 are from 0-29 hours 29-40 hours 40-80 hours and 80-114 hours For all the tests on

average the specific flux decreased by more than 65 The feed pressure increased from about

490 psi to more than 700 psi for a majority of the tests The net operating pressure increased

significantly for tests 1 and 4 The differential pressure increased from 16 psi to 27 psi for the

entire duration of the tests A summary of the performance parameters for the tests is listed in

Table 4 The significant increase in feed pressure requirement increase in net operating pressure

decrease in specific flux and increase in differential pressure suggested significant fouling and

scaling of the membranes The membranes were cleaned after 80 hours of operation using only

high pH (120) cleaning solution The specific flux recovered to initial value after chemical

cleaning suggesting that cleaning was efficient

504



Figure 7 Performance of SW-TM810L membrane Regions 123 and 4 represent different

tests performed with varying recovery

Table 4 Performance parameters for SW-TM810L tests

Note Test 2 was performed with 8 elements without recycle

The rejection of TDS and alkalinity was more than 95 The rejection of BOD-5 was 72 and

the rejection of COD was 63 Since the TM810L membranes are RO membranes with high

rejection capability TDS and alkalinity rejection was high and easily met discharge limits The

rejection of B0D-5 was low as it was associated with the passage of methanol through the RO

membrane The rejection of methanol is low through a RO membrane due to its low molecular

weight (3204 gmmol) All ions were rejected greater than 95 except for ammonia-N and

boron The rejection of Ammonia-N was less than 25 and boron rejection was approximately

75 Ammonia rejection by RO membranes is a function of pH The feed pH was 100 (plusmn01)

for the tests with SW-TM810L membranes Lower pH leads to the formation of ammonium

(NH4+) ions (higher rejection) Beyond a pH of 95 the dominant form of nitrogen compounds is

ammonia which is an uncharged molecule and difficult to reject by RO membranes hence the

rejection of Ammonia-N is low (Yoon and Lueptow 2005) Among the metals selenium

rejection was approximately 73 The rejection of boron (75) was better when compared to

000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505



the SW-NF270 membrane since boron speciates into the borate anion form at high pH and

results in better rejection by the SW-TM810L membranes

Determination of the constituents in the produced water limiting the performance of the

membrane process was critical to optimize the treatment process and achieve higher recoveries

Autopsy of membrane elements removed from the first pass SW-NF270 and second pass SW-

TM810L were performed to determine the nature of foulant and scalant deposited on the

membrane surface

Determination of Organic and Inorganic Content of Foulant Layer

A loss on ignition (LOI) test was performed to determine the organic content of the foulant

material deposited on the membrane surface A LOI value in excess of 35 represents the

presence of significant organic content of the foulant layer A LOI value of 85 was found for

the SW-NF270 membrane suggesting the presence of significant organic content deposited on

the membrane surface The LOI value for the SW-TM810L membrane was 22 suggesting low

concentrations of organic matter deposited on the membrane Since the SW-NF270 membrane

was used for the first pass organic matter not removed from the pretreatment processes reached

the membrane surface and eventually deposited Since the organics are removed by the SW-

NF270 membrane and the permeate was used as feed to the second pass SW-TM810L

membrane deposition of organic matter was restricted on the second pass membrane A Fourier

Transform-Infrared (FT-IR) analysis performed on the two membrane elements indicated the

presence of carbohydrates polysaccharide-like and protein-like material found on both the

membrane surfaces Also gram-positive and gram-negative bacteria were identified on both SW-

NF270 and SW-TM810L membranes The presence of bacteria on the membrane surface can

lead the biofouling issues eventually and cause a decrease in the performance of the membrane

and auxiliary equipments

To determine the inorganic constituents of the deposit layer Energy Dispersive X-ray Analysis

(EDX) was performed in combination with the SEM Since the SW-NF270 membrane was

fouled by predominantly organic matter (from LOI results) the weight percent of inorganic

elements such as silicon was low (less than 4) suggesting the presence of only a small amount

of clay on the membrane For the second pass membrane a high silicon content (24) was found

on the SW-TM810L membrane which suggested the presence of significant amounts of silica

scale and some inorganic clay matter in the form of and aluminum silicates The presence of

silica as aluminum silicates suggested the co-polymerization of silica with aluminum

DISCUSSION

The first pass membrane system consisting of NF270 membranes (SW and DT configuration)

were fouled significantly with organic matter The use of antiscalant in the first pass to prevent

BaSO4 precipitation was efficient as no BaSO4 scaling was found on the membrane surface The

presence of significant organic matter on the NF270 membrane suggested that a large fraction of

the organic matter passed through the pretreatment system and reached the NF membrane

Hence optimization of pretreatment or utilization of better pretreatment processes could

decrease the fouling potential of the first pass membranes and thereby decrease the cleaning

506



interval of the membranes Although organic fouling of the first pass NF270 membrane

occurred chemical cleaning was found to be efficient in recovering the specific flux to initial

values Hence operating the SW-NF270 system at 70 recovery and the DT-NF270 system

(treating concentrate of SW-NF270) at 71 recovery was feasible and more than 90 overall

recovery in the first pass was achievable

The second pass membrane system consisting of TM810L was fouled significantly with silica

Although the pH of the feed water was increased to 100 and a silica specific antiscalant was

used silica precipitation was predominant on the membrane surface The precipitation of silica

restricted the recovery of the second pass system to less than 75 Hence the overall recovery of

the entire system (both first and second pass) was restricted to a feed water recovery of less than

68 To increase the recovery of the second pass system silica levels in the feed water needs to

be reduced using a pretreatment process or a combination of pretreatment process to enable

higher recovery of the membrane system The second pass membrane systems using a seawater

RO membrane (TM810L) was effective in removing target contaminants and meeting discharge

limits in the treated water Certain constituents such as benzene methanol (constituting a large

fraction of BOD) and selenium discharge criteria were not met by the RO membranes But the

seawater TM810L membranes are also capable of meeting the discharge limits for boron Hence

further post-treatment steps were necessary to meet discharge limits for contaminants such as

methanol

Restriction of silica scaling on the membrane system is essential to achieve high (more than 80

) feed water recoveries Efficient pretreatment process for removal of silica might be necessary

to achieve higher feed water recoveries Efficient removal of silica in the feed water to the

membrane surface can facilitate the use of a single pass brackish water reverse osmosis

membrane or a ldquotightrdquo nanofiltration (NF) membrane and also achieve overall feed water

recoveries of more than 80

CONLUSIONS

bull High-pressure membrane processes such as nanofiltration and reverse osmosis were used

to achieve reduction in TDS and chloride content of produced water to meet discharge

limits satisfying a chloride concentration of less than 250 mgL in the treated water A

two pass membrane system was used to optimize the recovery of membrane treatment

and meet discharge limits The first pass consisted of NF270 membranes and the second

pass consisted of TM810L membranes Fouling potential of NF and RO membranes was

not substantially different when ceramic UF was used as pretreatment as opposed to the

use of organoclay or MYCELX filtration However the pressure drop across organoclay

filter bed and MYCELX cartridges increased substantially within a few hours of

operation

bull Initial analysis based on feed water quality determined that the recovery of the NF and

RO membrane system would be restricted due to the precipitation of silica barium

sulfate and calcium carbonate on the membrane surface The first pass membranes were

used to remove a large fraction of scaling precursors such as calcium sulfate and barium

from the feed water so that scaling issues due to calcium carbonate and barium sulfate

was restricted in the second pass

507



bull The first pass membrane removed 10-40 of calcium more than 70 of sulfate and

more than 30 of barium Due to removal of large fraction of calcium by the

nanofiltration membrane the pH of the first pass permeate could be increased to 100 to

increase silica solubility and thereby increase the feed water recovery of the second pass

bull More than 95 reduction of TDS in the feed water was achieved by the use of second

pass membrane The concentration of chloride in the permeate of the second pass RO

membrane was consistently lower than the discharge limit of 230 mgL The second pass

membrane also rejected more than 60 of COD and more than70 of BOD Alkalinity

removal of more than 95 was also achieved by the RO membrane Boron and selenium

removals were more than 70 by the second pass RO membrane

bull Although a variety of discharge limits were met by using the two pass membrane system

the overall feed water recovery was restricted to less than 70 due to organic fouling on

the first pass membranes and silica scaling on the second pass membranes

REFERENCES

Bartels C Dyke C (1990) Removal of organics from offshore produced water using

nanofiltration membrane technology Environmental Progress 9 183

Franks R Bartels C Nagghappan LNSP (2009) Performance of a reverse osmosis system

when reclaiming high pH ndash high temperature wastewater Proceedings of the AWWA Membrane

Technology Conference Memphis Tennessee

Mohammadi AVR Kazemimoghadam M (2003) Modeling of membrane fouling and flux

decline in reverse osmosis during separation of oil in water emulsion Desalination 157 369

Mondal S Wickramasinghe SR (2008) Produced water treatment by nanofiltration and

reverse osmosis membranes Journal of Membrane Science 322 162

Mueller J Cen YW Davis RH (1997) Crossflow microfiltration of oily water Journal of

Membrane Science 129 221

Sheikholeslami R Tan S (1999) Effects of water quality on silica fouling of desalination

plants Desalination 126 267

Tao FT Curtice S Hobbs R Sides J Wieser J Dyke C Touhey D Pilger P (1993)

Conversion of oilfield produced water into an irrigationdrinking quality water Society of

Petroleum Engineers Exploration and Production Environmental Conference San Antonio

Texas

Visvanathan C Svenstrup P Ariyamethee P (2000) Volume reduction of produced water

generated from natural gas production process using membrane technology Water Science

Technology 41 117 ndash 123

Yoon Y Lueptow RM (2005) Removal of organic contaminants by RO and NF membranes

Journal of Membrane Science 261 76

508



INTRODUCTION

Produced water water that is co-produced during oil and gas extraction represents the largest

source of oily wastewaters (Mueller et al 1997) The volume of produced water can be as much

as ten times the volume of oil extracted (Mondal and Wickramasinghe 2008) Produced water

consists of a combination of organic and inorganic compounds and production chemicals

Typical organic compounds present are aliphatic aromatic and polar compounds Inorganic

components include sodium potassium calcium magnesium chloride sulfate carbonate

silicates and borates Production chemicals can include emulsion breakers to improve separation

of oil and water and corrosion inhibitors (Mondal and Wickramasinghe 2008) The

concentration of these contaminants can vary significantly due to natural variation in the

geological formation and the type of oil-based product being produced (Franks et al 2009)

The typical method of dealing with produced water is deep well injection A portion of the

produced water is reinjected into oil producing zones to improve oil recovery through water or

steam flooding (Visvanathan et al 2000) The other portion of produced water is disposed off

through deep well injection Deep well injection is limited by the capacity of the injection wells

and discharge limits set by local governing agencies Due to this limitation in discharging the

produced water oil production companies are looking into options for treating the produced

water for surface discharge Example of discharge limits based on the class and purpose is listed

in Table 1 Certain discharge limits (Class 2AB) require a chloride concentration of less than 230

mgL in the treated water Treatment of such wastewater streams to meet low chloride and boron

discharge limits requires a technology such as NF and RO which can serve as an absolute

barrier for various contaminants The use of membrane technology also offers other advantages

such as a smaller footprint high level of automation and applicable for both onshore and

offshore oil exploration (Mondal and Wickramasinghe 2008)

Table 1 Example of surface water discharge limits for produced water

OBJECTIVES

Although high-pressure membrane processes such as NF and RO have been used in the past for

produced water treatment (Bartels and Dyke 1990 Tao et al 1993 Mohammadi et al 2003

Franks et al 2009) limited studies are available which have looked into the application of

advanced pretreatment technologies for controlling fouling and recovery optimization for NF and

Class Purpose Discharge limit

3D Beneficial use for livestock watering TDS lt 5000 mgL Oil and grease lt 10 mgL

65 lt pH lt 9 Turbidity lt 10 NTU Chloride lt 2000 mgL Boron lt 5 mgL

3B Aquatic life ephemeral streams TDS lt 5000 mgL Oil and Grease lt 10 mgL



Sulfur lt 2 ugL Chloride lt 2000 mgL Boron lt 5 mgL

2AB Potable water preserving fish life TDS lt 5000 mgL Oil and Grease lt 10 mgL



Sulfur lt 2 ugL Chloride lt 230 mgL Boron lt 5 mgL Benzene lt 22 ugL

Toluene lt 1 mgL Ethylbenzene lt053 mgL

492














recovery







Caustic1

3

2

DAF

UF

Organoclay

MYCELX

Spiral NF

DT NF

Spiral RO

Treated Water

Reject Water

Permeate

Concentrate

493























Corporation)

494










MYCELX Filtration







droplets

NF and RO Membranes























system

495































496





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508














recovery







Caustic1

3

2

DAF

UF

Organoclay

MYCELX

Spiral NF

DT NF

Spiral RO

Treated Water

Reject Water

Permeate

Concentrate

493























Corporation)

494










MYCELX Filtration







droplets

NF and RO Membranes























system

495































496





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508























Corporation)

494










MYCELX Filtration







droplets

NF and RO Membranes























system

495































496





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508










MYCELX Filtration







droplets

NF and RO Membranes























system

495































496





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508































496





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508





RESULTS

Feed Water Quality
















Oil and Grease 125

DRO 4

GRO 113

BOD-5 771

COD 1470

TDS 6280

pH 75


Sodium 3132

Chloride 1776

Calcium 31

Magnesium 3

Sulfate 8

Barium 58

Iron 08

Selenium 01

Silica 60 - 100

Methanol 280

Benzene 20

Toluene 30

Ethylbenzene 1

Xylene 1

497





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508





Performance of DAF






























of the water








498




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508




























499
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508
























60

80

100

120

140

160

180

200

220

240

00

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Sp

ecif

ic F

lux

2

5 d

eg C

gfd

psi



Recovery

Flux 25 deg C

Chemical Cleaning

Rec

ov

ery

Flu

x

25

deg

C

gfd

Ceramic UF

500
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508
















65









0

01

02

03

04

05

06

07

08

09

1

00

100

200

300

400

500

600

700

800

900

1000

000 2000 4000 6000 8000 10000 12000 14000


Flux 25 deg C gfd

Recovery

Time hr

DT-NF90

Recovery

Chemical Cleaning

Flux 25 deg C


501




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508




























membrane system

502




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508




Note












01

015

02

025

03

00

100

200

300

400

500

600

700

800

900

1000

00 500 1000 1500 2000 2500


Flux 25 deg C gfd

Recovery

Time hr

SW-NF270

Flux 25 deg C

Recovery


12 3

4



1 024 026 26 29

2 022 024 32 28

3 038 039 32 32

4 035 03 22 32

503




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508




10)
































504




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508




















000

010

020

030

00

100

200

300

400

500

600

700

800

900

1000

00 200 400 600 800 1000 1200


Flux 25 deg C gfd

Recovery

Time hr

SW-TM810L

Flux 25 deg C

Recovery


12

3

4



1 008 005 115 225

2 014 005 412 413

3 012 002 78 65

4 009 002 104 382

505









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508









membrane surface


























DISCUSSION








506





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508





















methanol







CONLUSIONS










operation







507
















REFERENCES

















Texas






508
















REFERENCES

















Texas






508



Application of Nanofiltration and Reverse Osmosis Membranes for Produced Water Treatment

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Transcript of Application of Nanofiltration and Reverse Osmosis Membranes for Produced Water Treatment