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APPEA Journal 2010 50th ANNIVERSARY ISSUE—1FINAL PROOF 2—MEIJER 10 MAR 10

REMOVAL OF DISSOLVED AND DISPERSED HYDROCARBONS FROM OIL AND GAS

PRODUCED WATER WITH MPPE TECHNOLOGY TO REDUCE TOXICITY

AND ALLOW WATER REUSE

Lead authorDick

Meijer

D.T. Meijer1 and C. Madin2

1Veolia Water Solutions & Technologies, the NetherlandsPO Box 2506710 BG EdeThe Netherlands2Veolia Water Solutions & Technologies, AustraliaLevel 4, Bay Centre65 Pirrama RoadPyrmont NSW [email protected]@veoliawater.com.au

ABSTRACTLegislation worldwide and current technologies used in

the treatment of offshore oil and gas/condensate produced water are mainly aimed at the removal of dispersed hydrocarbons (dispersed oil). From the beginning of this century, new insights in the North Sea area revealed that specific contaminants in produced water are toxic and their impact on the environment was assessed. This insight was later supported by work in the Philippines. A comparison of water with the same total organic carbon (TOC) levels showed in one case that the unknown toxic content was higher with an unexpected disastrous effect on the biocultures. Overall parameters like biological, chemical and total oxygen demand (BOD, COD and TOC) are of no value in identifying and managing the toxic content of waste and produced water streams. New extraction based technologies such as the Macro Porous Polymer Extraction (MPPE) technology appear to remove dispersed and dissolved toxic constituents and reduce the environmental impact. Industrial applications show a >99% toxic content reduction in produced water streams. A recent application (at Woodside Petroleum’s Pluto LNG project) is described where the ultimate reuse of produced water was as demineralised water in an LNG plant. Emerging potential is presented for floating LNG plants currently investigated in conceptual studies by the oil and gas industry. Finally, fundamental technological mechanisms are presented that are required to meet zero harmful discharge legislation.

KEYWORDSMPPE, produced water reuse, wastewater reuse, ground-

water reuse, dissolved and dispersed hydrocarbons, zero harmful discharge, ZHD, Environmental Impact Factor, EIF.

INTRODUCTION

At the moment, technologies used in the treatment of offshore produced water on oil and gas platforms are mainly aimed at the removal of dispersed hydrocarbons (dispersed oil). The focus on the removal of dispersed hy-drocarbons is due to past and still current legislation that aims to reduce dispersed oil emissions. In the late 1990s and at the beginning of this century, attention has shifted towards the effect of other constituents of the produced water. This has led to a better understanding of the impact of the individual toxic constituents on the environment and the development of new technologies to abate them. Extraction technologies like C-tour and the Macro Porous Polymer Extraction (MPPE) technology have shown very good performance reducing harmful discharge.

This paper will deal with: present emission regula-tions; produced water composition and environmental issues; technological mechanisms reducing the environ-mental impact factor; MPPE technology; environmental impact toxicity reduction with MPPE; analytical parameter and approach to produced water treatment; and, the future and reuse of produced water.

PRESENT EMISSION REGULATIONS FOR OFFSHORE PRODUCED WATER

In the North Sea (Fig. 1), countries like the United Kingdom, Norway, the Netherlands, Denmark and Germany have been fishing in the same pond for ages. It has taken them quite some time to agree on property zones, fishing zones and fishing quota. Ever since oil and gas production started in the North Sea in the 1970s, produced water emissions have attracted major attention. Despite the gov-ernments, the fishing industry and oil and gas producers having their own agendas, these countries formalised their efforts towards prevention and elimination of pollution of the marine environment in 1978 by means of the Paris Commission (PARCOM) and since 2002 by means of the Oslo Paris Convention for the Protection of the Marine En-vironment of the North East Atlantic (OSPAR convention). The present target of 40 mg/l oil-in-water was endorsed by PARCOM in 1978 in The Hague.

Both governments and representatives of the oil and gas industry for each country are participating in the OSPAR convention. For a very long period they have used the criterion of ≤40 ppm dispersed oil as the leading crite-rion for offshore produced water discharge. Only recently

2—50th ANNIVERSARY ISSUE APPEA Journal 2010 FINAL PROOF 2—MEIJER 10 MAR 10

D.T. Meijer and C. Madin

Figure 1. The North Sea.


Removal of dissolved and dispersed hydrocarbons from oil and gas produced water with MPPE technology

they have reduced the dispersed oil target from 40 ppm to 30 ppm and sought a 15% total emission reduction in 2007 compared with 2000; however, some of the individual OSPAR countries have adopted a more detailed approach regarding the composition of produced water and its impact on the environment.

For example, in the Netherlands a declaration of intent (Ministry of Economic Affairs, 1995) was agreed in 1995 between the National Oil and Gas Exploration and Produc-tion Association (NOGEPA) and the Dutch Government to reduce the benzene emission in the offshore produced water to 60% of the 1990 level by 2000. This led to inves-tigations and field tests of new emerging technologies to remove both dissolved and dispersed hydrocarbons and other contaminants in the second half of the 1990s. In the beginning of this century these new technologies were first implemented commercially on the most critical offshore platforms in the Dutch part of the North Sea (Dalen, 2004).

In the second half of the 1990s the Norwegian oil and gas industry (Statoil, Hydro) took the initiative to study the toxic impact of the individual constituents of the produced water and their impact on the environment. A so-called en-vironmental impact factor (EIF) was introduced to quantify the environmental impact of the produced water stream of each specific platform. Based on this approach the Nor-wegian Government introduced a zero harmful emission policy in the beginning of this century with the objective to reach zero harmful emission of all platforms in 2007.

In the rest of the world national oil and gas produc-ers associations and governments are following these de-velopments in the North Sea by setting their emission regulations to comparable levels as in the North Sea. For example, in 2007 the Australian Government tightened the emission regulation for dispersed oil from 50 to 30 ppm (Lowe, 2006). In Malaysia the present 100 ppm is being reconsidered (Ithin and Christopher, 2006), but actually levels <50 to as low as 30 ppm are reached in practice. At an international conference in 2006, a paper from the Philippines recommended putting more emphasis on the harmful impact of the oil and gas produced water emis-sions (Phillips et al, 2006).

PRODUCED WATER COMPOSITION AND ENVIRONMENTAL IMPACT AND

MECHANISMS TO REDUCE IT

When taking a closer look at the oil and gas produced water composition, one can identify non polar and polar hydrocarbons on the one hand, and dispersed and dissolved hydrocarbons on the other hand. The non polar aliphatics are mainly dispersed and have a tendency to float, while polar hydrocarbons are dissolved and are not floating. Within the dissolved hydrocarbons one can identify hy-drocarbons with a clear toxic effect on the environment (toxic, carcinogenic, mutagenic, less biodegradable, etc) and hydrocarbons that are less or non toxic and more bio-degradable. A schematic presentation of these categories is given in Figure 2.

The general composition of oil and gas produced water streams is qualitatively similar all over the world, but there

are quantitative variations in composition from platform to platform.

For this paper, a simple graphic is used to represent the composition in terms of concentration ranges for the individual components as in Figure 3.

Constituents in produced water

As indicated, the dispersed oil content can vary from 100 ppm down to 40 ppm or even 30 ppm or less depending on the flotation and coalescing techniques applied. Toxic dissolved hydrocarbons like BTEX (benzene, toluene, ethyl benzene, xylene) can then still vary between 100 and 800 ppm while levels of PAHs (polyaromatic hydrocarbons), and alkyl phenols will be some hundreds of ppb levels. More polar, less toxic and more readily biodegradable com-ponents (like carboxylic acids, alcohols, etc) are generally present at hundreds of ppm. The Norwegian oil and gas Oil & Gas produced water compositionHydrocarbons Non polar More polar

Dispersed AlphaticsFloating Separators / flotation

“Standard”: 40 ppm“Ad d” 10 30

Negligible“Advanced”: 10-30 ppm

DissolvedNot floating

Aliphatics Alcohols/Methanol/GlycolCarboxylic acids

“non toxic”

T i A ti

Hundreds of ppm

ToxicCarcinogenicMutagenic

AromaticsBTEX 100 – 800 ppmPAHs 200 – 6,000 ppb

Alkyl PhenolsTen – Hundreds ppbMutagenic PAHs 200 6,000 ppb Ten Hundreds ppb

Figure 2. Oil and gas produced water composition.Produced Water compositionCompounds ppm Composition

Dispersed oil =

Dispersed hydrocarbons =

40 - 100DA

Dispersed Aliphatics = floating

Dissolved hydrocarbonsBToxic:

- Benzene- Toluene

200 - 800 B

TAromatics- Ethyl benzene

- Xylene- PAHs and NPDs 0.2 - 6

EX

Aromatics

PAHs- Alkyl Phenols 0.1 - 0.2

Dissolved hydrocarbonsA Ph

PAHs

hundredsReadily BiodegradablePolar:- Acids

Polar

- Alcohols (Methanol)

Figure 3. Produced water composition.



companies Hydro and Statoil (recently merged into one company— Statoil) have been carrying out extensive stud-ies and modelling leading to the definition of the EIF. They determined the environmental impact of each constituent of the produced water of each platform. Based on this ap-proach they quantified the environmental impact of the produced water stream of each individual platform on its environment over the operational lifetime of the platform.

Individual constituents contributing to the Environmental Impact Factor

In Figure 4, the contribution of the individual compo-nents on the total EIF is shown for three different plat-forms in the Norwegian part of the North Sea. From these three EIF compilations, one can draw the conclusions that the contribution of each constituent varies significantly among platforms. Generally it can be concluded that PAHs, especially the NPDs (naphtalenes, phenanthrenes and dibenzothiophenes) at ppb level have the highest impact, followed by aromatics like BTEX and dispersed oil at ppm levels, then alkyl phenols and lastly the dissolved polar compounds contribute least to the EIF.

These observations are supported by the results of a recent study carried out by Shell Philippines Explora-tion B.V., Rob Phillips Consulting Pty Ltd and Sustain-able Solutions Services at the request of the Philippine Government. They studied the toxic impact of a gas and gas/condensate produced water stream (Shell Malampaya) on the environment and concluded that the polyaromatic hydrocarbons, especially the naphthalenes, and the BTEX, have the highest impact on the environment. Remarkably they found that the alkyl phenols do not have a signifi-cant impact on the water environment around the Shell Malampaya platform. This is different from the results of the Norwegian studies. This shows that both the compo-sition and quantity of the produced water as well as the characteristics of the marine environment determine the environmental impact of the individual produced water stream. It may be the warm waters around the Philippines (average temperature of 20˚C or higher compared to the 7–10˚C in the North Sea) that cause the alkyl phenols to have a low to insignificant impact on the environment.

Having observed that the dissolved toxic hydrocarbons like PAHs, BTEX, and alkyl phenols commonly have a higher impact on the environment than the dispersed ali-phatics, the question arises: what technologies will greatly reduce the EIF?

TECHNOLOGICAL MECHANISMS TO REDUCE THE

ENVIRONMENTAL IMPACT FACTOR

Having concluded that the constituents contributing to the EIF are predominantly dissolved, it is clear that the basic physical and chemical mechanisms on which tech-nologies are based, are fundamentally determining the potential effect of these technologies to reduce the EIF. This means that technologies based on flotation, gravity

and coalescing, which are aimed at removal of dispersed hydrocarbons, can only have a limited effect on the reduc-tion of the EIF. For removing dissolved components, other fundamental mechanisms like absorption, adsorption, ex-traction, membrane filtration or oxidation have to be used. Techniques based on adsorption, like activated carbon or polymeric micro porous sorbents with big internal sur-faces are certainly able to remove dissolved hydrocarbons; however, these technologies as well as membranes will be strongly negatively influenced by other constituents of produced water, such as emulsions, dispersed oil, surface active chemicals like corrosion and scale inhibitors and H2S scavengers.

So far it seems that extraction-based technologies are more effective in produced water applications. Statoil has studied, calculated and compared the effect of different technologies on oil produced water streams of different platforms (Grini et al, 2002) whereby each technology was applied for one platform only. The calculations were based on the reported performances of the technologies and the EIF compositions of the individual used water streams. In that study it appeared that the MPPE technology had the highest reduction of about 84% of the EIF for oil produced water. It is clear that the reducing effect of MPPE on the EIF depends on the composition of the constituents that are contributing to the EIF. This will of course vary from platform to platform; however, the impact can be deter-mined by the extent to which the MPPE technology can remove the individual constituents contributing to the EIF. For gas produced water streams, Statoil came to a removal of 95–99% with the MPPE technology.

MACRO POROUS POLYMER EXTRACTION

(MPPE) TECHNOLOGY

As indicated in the previous paragraphs, the MPPE technology is basically a liquid-liquid extraction technology where the extraction liquid is immobilised in the macro porous polymer particles. The MPPE process has been specifically designed for optimal use of these MPPE par-ticles in water treatment.

Composition and emission targetsCompounds ppm Composition EIF*(1) EIF*(2) EIF*(3)

Dispersed oil =

Dispersed hydrocarbons =

40 - 100DA DA DA DA

Dispersed Aliphatics = floating

Dissolved hydrocarbonsB BTEX BTEX

BTEX

Toxic: - Benzene- Toluene

200 - 800

Aromatics

B

T

BTEX BTEX

- Ethyl benzene- Xylene- PAHs and NPDs 0.2 - 6

Aromatics

PAHs

EX PAHs PAHs PAHs

- Alkyl Phenols 0.1 - 0.2

Dissolved hydrocarbonsA PhPAHs

hundredsReadily BiodegradablePolar:- Acids

Polar

A Ph A Ph A Ph

- Alcohols (Methanol)

* EIF = Environmental Impact Factor

A PhMeth Meth Meth

Figure 4. Composition and emission targets.



MPPE particles

A scanning electron microscopic (SEM) photograph of macro porous polymer particles is shown in Figure 5.

The porous polymer particles have a diameter of 1,000 micron, with pore sizes of 0.1–10 micron. The poros-ity is 60–70%. These polymers were initially developed as controlled release media in medical applications. The application in water treatment started in 1991. Initially the macro porous polymer was used for absorbing dispersed oil from water. Initiated by the oil and gas industry, the idea emerged to develop a medium to remove dissolved hydrocarbons from water by immobilising an extraction liquid in the pores of the polymer. As a result this (pat-ented) MPPE technology was developed in the mid 1990s.

MPPE process

In the MPPE water treatment process, hydrocarbon-con-taminated water is passed through a column packed with MPPE particles. The particles are porous polymer beads that contain a specific extraction liquid. The immobilised extraction liquid removes the hydrocarbon components from the process water. The purified water can either be reused or discharged.

Periodical in-situ regeneration of the extraction liquid is accomplished by stripping the hydrocarbons using low pressure steam. The stripped hydrocarbons are then con-densed and separated from the water phase by gravity. The almost 100% pure hydrocarbon phase is recovered, removed from the system and left ready for recycling or disposal.

The condensed aqueous phase is recycled into the sys-tem. The application of two columns allows continuous operation with simultaneous extraction and regeneration. A typical cycle is one hour of extraction and one hour of regeneration. Figure 6a shows a simplified flow-sheet of the MPPE process and Figure 6b is a photo of a full-scale MPPE installation.

The MPPE technology can reduce dissolved and dis-persed hydrocarbons such as aliphatics, aromatics (BTEX), polyaromatic and halogenated (chlorinated) hydrocarbons with 99.9999% removal (1,000,000 times reduction), if re-quired.

MPPE technology can be used for treatment of offshore produced water, process water, wastewater and ground water in a wide variety of markets including the offshore gas and oil, chemical, coatings and pharmaceutical in-dustries. MPPE can withstand complex produced water environments containing salt, methanol, glycols, corrosion inhibitors, scale inhibitors, H2S scavengers, demulsifiers, defoamers and dissolved (heavy) metals.

Chemical constituents reduction with MPPE

After the MPPE technology was developed, the first ap-plication in 1994 was actually on a gas offshore produced water stream of Elf Aquitaine in Harlingen (which later became Total, then Vermilion; Fig. 7).

The MPPE separation performance was above 99% at 3,000 ppm influent levels from the very beginning for the target compounds (BTEX) and the results have been published in a Society of Petroleum Engineers conference (Pars and Meijer, 1998). At that time Elf Aquitaine had developed a specific steam stripper (Kloppenburg and Venema, 1997), but has abandoned that technology for produced water treatment due to costs and operational/maintenance reasons.

As legislation at that time did not formally require a reduction in dissolved aromatics (BTEX) or polyaromatic hydrocarbons (PAHs), it took a while before the MPPE tech-nology was requested by the offshore industry. Neverthe-less both governments (NOGEPA study on 55 technologies (Kaa and Petrusevki, 1988), OSPAR (OSPAR, 2004) and the oil and gas industry (Orkney Water Test centre (ERT/Orkney Water Technology Center, 1997), were addressing the issue of dissolved aromatics and PAHs emission in produced water. The first offshore field test was carried out by NAM (Shell/Exxon) on L2 in the Netherlands’ part of the North Sea. It was a 4 month test with excellent results, which were presented at the 2001 Offshore Technology Conference (Meijer and Kuijvenhoven, 2001). Some more offshore field tests were carried out on gas/condensate produced water by Statoil (in Norway) and Shell (in Ma-laysia). The combination of successful offshore field tests at the end of the 1990s and beginning of this century and governmental pressure in the Netherlands has led to the installation of the first commercial MPPE units offshore, on the most critical platforms in the Dutch part of the North Sea (Total F15A, NAM K15A and K15B). These units have been in operation successfully since 2002 with a separa-tion performance of >99% of BTEX, PAHs and aliphatics at 300–800 ppm influent concentrations.

Due to further developments in OSPAR regarding the issue of dissolved aromatics and PAHs emission, a formal investigation was carried out on request of OSPAR on oil produced water of NAM and Total (Meijer et al, 2004). Later an extensive offshore field test was carried out by Hydro on Troll B (Pollestad, 2005). In these field tests a Figure 5. Internal structure of the macro porous polymer.



consistent reduction of >99% was observed for BTEX and PAHs. For aliphatics below C20 a consistent reduction at 95–99% removal was measured in all field tests. For the total aliphatics removal the picture was mixed: 91–95% for Total and >95% for Troll B.

A summary of the results is presented in Figure 8.The separation performance of the flotation technolo-

gies and the MPPE technology on the chemical composition of oil and gas produced water is schematically presented in Figure 9.

ENVIRONMENTAL IMPACT/TOXICITY REDUCTION WITH MPPE

A real life case with Statoil and Gassco in Kollsnes (NO)

SAME TOC (TOTAL ORGANIC CARBON) LEVELS, BUT BIOACTIVITY STOPPED

In autumn 2004 a new gas/condensate production plat-form Kvitebjørn was tied-in to the gas treatment plant Figure 6a. The MPPE process.

Figure 6b. MPPE unit at LBC Rotterdam, the Netherlands. Figure 7. MPPE unit at Vermilion, Harlingen, the Netherlands.



of Statoil and Gassco in Kollsnes, west of Bergen in Nor-way. The gas treatment plant at that moment was already treating gas/condensate from Troll A, B and C as well as Visund. Shortly after the tie-in of Kvitebjørn in October 2004, the biotreatment plant at the site ceased to func-tion properly and by January 2005 nearly all bioactivity had stopped. This happened without any increase in total organic carbon content (TOC).

AFTER MPPE UNIT INSTALLATION BIOACTIVITY RESTORED WITHIN 3 MONTHS

After installation of a mobile MPPE unit in the begin-ning of 2005, bioactivity was restored within three months. Afterwards it was discovered that the toxic fraction of the influent increased significantly, while the TOC of the influ-ent did not increase. Kvitebjørn produced water contains more toxic substances than the water from the Troll and Visund fields. The BTEX was 20–100 times higher (600 mg/l from Kvitebjørn), PAHs were 10 times higher and alkyl phenols (C2/C4) were 10–50 times higher. Large variations in BTEX were observed especially during start up. The

conclusion was that the biomass was poisoned due to the higher concentrations of BTEX, PAHs and alkyl phenols. BTEX content greater than 12 mg/l could be toxic to an unadapted culture (Bergensen and Jacobsson, 2006); MPPE removed BTEX and PAHs at design levels (98–99%) (Ber-gensen et al, 2006).

Environmental Impact Factor reduction with MPPE

The above real life experience with the MPPE technology supports the views of the Norwegian oil and gas industry and study results that the MPPE technology achieves EIF reduction.

In studies carried out by Statoil of different technolo-gies on different platforms (Grini et al, 2002; Buller et al, 2003), it was concluded that the MPPE technology was able to reduce the EIF by 84 to close to 100% for the targeted produced water streams (without floatation and coalesc-ing pretreatment). Conventional flotation and coalescing techniques for reducing dispersed oil may reduce the EIF with 30% of the untreated water.

The effect of MPPE and flotation techniques is sche-matically presented in Figure 10.

The successful examples both onshore and offshore has led to the implementation of the MPPE technology by Hydro (Sjothun, 2002) and Shell (Salevik, 2009) in the prestigious Ormen Lange gas/condensate field project in Norway (see Fig. 11), which involves deepsea (1,000 m) gas and condensate production with gas treatment onshore (100 km from gas field) and distribution by the world’s longest underwater pipeline to the United Kingdom and the rest of Europe.

Real life robustness of MPPE

An example of the robustness of MPPE is shown in Figure 12 where the design values and real life analyses since 1994 are given for an MPPE unit treating gas produced water

Figure 8. MPPE performance in offshore produced water.

Figure 9. MPPE effect on chemical composition. Figure 10. MPPE effect on EIF.



and a mono ethylene glycol (MEG) regeneration stream. The design was to reduce dissolved BTEX from 1,500 ppm to <1 ppm. In practice influent levels of BTEX (dispersed and dissolved aromatics) from 1,400–7,700 ppm and ali-phatics (dispersed and dissolved oil) from 150–1,437 ppm were reduced as a total to 3–0.5 ppm in the outlet.

ANALYTICAL PARAMETERS AND APPROACH TO PRODUCED WATER TREATMENT

Analytical parameters

It is clearly shown in the Statoil Kollsnes case that in-tegral analytical parameters like BOD, COD, TOC are not specific enough to characterise the quality of the produced water with respect to its impact on the environment.

The EIF seems to be the most ideal and comprehensive way of quantifying the environmental impact, but is not regarded as practical for monitoring on a periodical or daily basis.

At present, gas chromatography possibly combined with mass spectrometry is the most appropriate technique to

measure the dissolved toxic compounds BTEX, PAHs and alkyl phenols as well as the dispersed aliphatics on a daily/periodical basis. The GC-MS technique helps to focus on the removal of the toxic content of produced water.

An approach to treating produced waterThere seems to be a logical difference in the approach

of treating produced water from oilfields and gas/conden-sate producing fields. This is due to the fact that for gas/condensate fields the produced water flow rates may vary between 3 m3/h and 150–200 m3/h with a very high dis-solved toxic hydrocarbon content of 800–1,000 ppm. Oilfield produced water may vary from 50–2000 m3/h or more with lower levels (100 ppm) of dissolved toxic hydrocarbons.

In treating oil produced water it goes without saying that conventional techniques based on flotation, coalesc-ing principles will always be necessary; however, to reduce the toxic content, an adsorption or an extraction based technology like MPPE is needed. For oil produced water this can be done after passing through hydrocyclones or other flotation techniques and prior to letting the water flow overboard.

Figure 11. Ormen Lange gas/condensate field project in Norway.



In gas/condensate produced water streams, studies have shown that MPPE can remove the whole spectrum of ali-phatics, as well as the BTEX and PAHs. In this case MPPE can effectively be installed after the gas/water separator, a slug catcher or a simple plate separator, and the degasser. The condensed overhead vapors of the glycol regenera-tion, which normally contain very high BTEX loads, and contaminated rain water runoff can be combined with this produced water prior to MPPE treatment. In the Or-men Lange Gasfield no pretreatment, apart from a solids prefiltration, is installed. The MPPE treatment results in practically zero harmful emissions when the inlet concen-tration of dissolved and dispersed hydrocarbons is as high as of 800–1,000 ppm. In special cases like the produced waters of the Ormen Lange gas/condensate field and Statoil Kollsnes, after MPPE has removed the toxic content, the water receives biotreatment before discharge. The reason for this extra treatment is probably the fact that this is an onshore treatment and discharge is then taking place in the vicinity of coastal areas.

FUTURE: REUSE OF GAS/LNG PRODUCED WATER

On the Burrup Peninsula in Australia, Woodside is em-ploying water treatment technologies in the Pluto LNG plant so that the produced water can be reused. The se-quence of the water treatment technologies that are going to be used is presented in Figure 13a and 13b.

In this remote area fresh water is scarce and drought conditions have increased in recent years. Using gas pro-duced water that has to be treated anyway before discharge (CPI, MPPE) is considered a better raw water source than seawater. The Pluto Effluent Treatment Plant (ETP) is be-ing constructed and is planned to be started up in 2010.

Presently, floating LNG plants (FLNG) are investigat-ed in conceptual studies by the oil and gas industries. Floating LNG plants with a future of being positioned in environmentally sensitive areas—like Australia or the Barents Sea—and that have the potential to be relocated

several times will need onboard technologies to secure zero harmful discharge.

CONCLUSIONS

Hydrocarbon emission to the environment through re-lease of oil and gas produced water has attracted major attention worldwide from governments and operators. Hydrocarbon emission standards vary significantly in different jurisdictions, but they tend to target the toxic compounds. Present legislation is predominantly aimed at dispersed oil reduction.

There is a definite worldwide trend towards reduc-tion of the toxic content of produced water aiming at a minimal (or zero) harmful impact on the environment. EIF is a measure of the toxic content of produced water that depends on the specific constituents such as PAHs, BTEX, alkyl phenols and to a lesser extent on dispersed oil. Overall analytical parameters like BOD, COD, TOC are not adequate for identifying and implementing technologies that are specifically aimed at reducing the toxic content. GC-MS techniques can differentiate the toxic compounds and are appropriate analytical tools. Technologies based

Figure 12. A real life example of design versus actual MPPE per-formance.

Figure 13a. Gas/condensate production and LNG plant (general concept).

Figure 13b. LNG plant waste water treatment and reuse scheme (general concept).



on fundamental mechanisms like adsorption, absorption, extraction or oxidation are required to reduce the dissolved toxic content of produced water to a minimum. Coalescing and flotation based technologies are often needed prior to these techniques.

Current developments show reuse of gas produced water in future LNG facilities.

ACKNOWLEDGEMENTS

The basis of this paper is the series of field tests carried out by and on request of Elf Aquitaine, Total, NAM, Shell, Statoil, Hydro and OSPAR resulting in a wealth of informa-tion and publications. Individual contacts and exchange of views with the various experts from these companies, as well as their papers mentioned in my references, have been of great value.

This paper would not have been possible without the help and support of Mrs Marijke Kuntzel for consuming the continuous stream of new drafts and her constructive comments.

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THE AUTHORS

Dick Meijer is managing director of VWS MPP Systems B.V. a business unit of Veolia Water Solutions & Technolo-gies STI, acquired from Akzo Nobel on 1 December 2006. He was one of the co-founders of this business within Akzo Nobel and since 1994 he has been responsible for the growth and development of the business. Dick

started his professional career with Akzo Nobel in 1974 with the R&D salt and basic chemicals division. After five years Dick was promoted to the strategic planning of the coatings divi-sion. Upon completion of a further five year term, he became technical marketing manager BU protective coatings for three years. In 1987 Dick assumed the position of sales and market-ing manager of the BU non wovens, before being promoted to corporate director for Akzo Nobel’s strategy and planning for the chemicals, fibers divisions and mergers and acquisitions in 1990. Dick received a MSc in physical chemistry from Leiden University and completed various courses in business administration at the Technical University in Twente and marketing in Insead. Dick has presented various papers at international conferences in New York (Nobel merger), Caracas (SPE), Houston (OTC), London/Vienna (ERTC), London/Aberdeen/Kuala Lumpur (various off-shore conferences). Dick is a native Dutch speaker. In addition to his mother tongue, he is also fluent in English, German, Danish and has good knowledge of French.

Chris Madin is the business develop-ment manager for the projects group of Veolia Water Solutions & Technologies Australia. Chris is a chemical engineer with experience in the processes and technology for the treatment of all types of water including wastewater, potable and industrial process water. Chris’s focus is difficult industrial water

treatment, including water from oil and gas operations, produced water, mining contaminated water, advanced desalination and similar processes. Chris has worked on projects in Australia and the USA, specialising on water treatment processes.

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