demulsifiers water in oil emulsion separation results

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Demulsifiers: Water-in oil emulsion separation results Chandran Udumbasseri, Technical Consultant

[email protected]; chandran.udumbasseri#@gmail.com

Introduction Crude oil emulsion breaking is one of the hardest operations in oil separation

from entrapped saline water. The oil coming out of a crude oil drilling well is composed of dissolved natural gas, water trapped as free and emulsified,

and solid materials like sand, mud, insoluble inorganics, sludge, and other rock sediments from the bottom of the well. The water is usually salty and

varies from well to well. The composition of each well is different. It necessitates different types of processing chemistry for each well. There is

only a general outline of processing for all types of crude emulsion separation but needs specific processing chemistry well.

The crude oil coming out of a well is sent to separating plant where demulsifier is injected in the incoming pipeline. Due to turbulent flow the

demulsifier gets mixed up evenly in the crude oil and initiates emulsion

breaking. The crude then goes to high pressure separating tank (horizontal, slanted, spherical, hemispherical or vertical) where freed natural gas moves

to collecting compressors, water separates at the bottom while oil float as top layer.

The water is drained from the tank as the oil is allowed to move to low pressure separator where remaining gas is removed from the crude oil. The

crude which is wet coming out of this second separator is sometimes heated to facilitate emulsion breaking or allowed to go to dehydrator unit for

removing residual water electro statically. After complete water removal by dehydrator the oil is dry in nature with some crystals of salt remaining in the

suspended state in the oil. So the oil is again washed with water by mixing wash water. Outgoing oil is tested to ensure dryness and salt level.

Some test results are given below for different oils

Saudi oil Flow diagram

HPPT

HPPT

LPPT

DehydratorDesalter

Shipment line

Production Header

Sample Point

Wash water injection

mailto:[email protected]

mailto:chandran.udumbasseri#@gmail.com

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1. Plant 1

Process Data

Process Information

Total production rate 233000BD

Total crude oil rate 145000BD

Percentage water cut 38-42%

Temperature at production header 130F

Oil level in separators & dryers 50%

Salt in crude, average 5 PTB

Water cut

Free Water 20-40%

Total water 52-58%

Emulsion 12-38%

After bottle testing the best performing demulsifier bases are given below

Demulsifier

Bases

Conc Water

dropping

mls/minutes W

Q IQ

Salt

content Chemistry RSN

ppm 10 20 40 PTB DG270 20 12 20 32 F F- 17.85 Modified ester 6.7

DI938 20 6 9 12 F F 48.8 Polymeric polyol 7.7

Croda-D3501X 20 9 16 18 F F 24.6 Alkoxylated phenolic resin 15

D311 20 9 12 18 P F 27.9 Oxylate phenolic resin 18

D309 20 8 9 10 G F 46.6 Oxylate phenolic resin 29

DB5951 20 7 12 24 P F + 27.9 Tetrol 11

DI945 20 10 11 18 F F 44.9 Amine alkoxylate 16

D3575X 20 13 19 24 G G 19.38 Mixed resin ethoxylate 17

DB9393 20 0 0 Tr - - 3.4 Amine ethoxylate 6.7

D3422X 20 0 3 12 F F- 3.56 Imine alkoxylate 8

D510 20 4 6 12 P P 7.28 Imine alkoxylate 11

DB9947 20 4 16 18 F G 9.17 Resin EO/PO alkoxylate 13

DB9429 20 5 18 22 G F+ 35.4 Resin alkoxylate 10-14

D304 20 5 12 14 G G 13.17 Resin alkoxylate 21

DRA21 20 9 14 16 P P 8.25 Oxy phenolic resin 21

DRI9030 20 0 5 16 F G 11.68 Esterified phenolic polymer 7-8

DRI9037 20 0 10 16 F F 7.68 Polyol 7-8

RDM9510 20 0 5 8 P P 9.24 Blend 7-9

13190 20 9 18 20 G F 7.3 Epoxy resin 7.6

PG1.5 20 0 0 5 P P 5.15 Polyglycol 14.1

PG2.5 20 1 5 16 F F- 9.5 Poly glycol 17.3

DRC232 20 8 10 14 G G 53.9 Oxylated resin 14.3

DEE5 20 0 0 0 - - 1.48 Polyethylene amine mixture 6

RS19 20 10 24 30 G G 17.82 Alkoxylated resin 12

RS15 20 5 14 24 F F 29.2 Alkoxylated resin 13

CB361 20 9 16 18 G F 27.8 NPF-EO/PO

DB9392 20 0 9 22 G P 2.49 PEI alkoxylated 8.3

Basorol-P17R2 20 2 2 6 G P 5.5

Syn PEL101 20 5 9 14 G G 35.4

Syn T1301 20 14 20 20 G F 30.2

W033 20 3 10 13 G G 29.2 Polyol 16

W0801 20 3 5 10 G G 24

3073 20 4 6 15 F P 37.1

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The following formulations were found better performers

Selected Formulations Formulation Ratio Grading Average activity

DB9947/DB9392/DB9393 2/2/1 1 42%

W033/DB9392/DB9393 2/2/1 2 42%

DB9947/DG270/DB9393 2/2/1 3 42%

DB9958/DG270/DB9393 1/1/1 4 42%

DRI9037/DB9392/DB9393 2/2/1 5 50%

DG270/DB5951/DB9393 1/2/1 6 50%

Conclusion-Final Formulation

Formulation

Conc Water dropping mls/minutes WQ IQ

Top oil water cut, %

Salt content

ppm 10 20 40 W1 W2 ∆ PTB

incumbent 20 Tr 4 18 F2+ F 5.2 5.2 0 24.9

30 5 18 50 F- P 2.0 2.15 0.15 5.67

(F1)DB9947/DB9392/DB9393 2/2/1

20 4 6 42 VG G 0 0 0 2.04

30 14 48 54 VG G 0 0 0 2.08

(F2)W033/DB9392/DB9393

2/2/1

20 5 12 36 G F+ 0.05 0.05 0 1.29

30 20 36 52 F- G 0 0 0 0.84

Evaluation

Evaluation of results: The final demulsifier is based on DB9947, DB9392, DB9393, DB 5951, DB9958 (all BASF bases), DG270 (Marchem) and W033

(Deshi) The table of bases screening is giving the following data for using

formulations

Formulation

Conc Water dropping mls/minutes

WQ IQ

Salt conte

nt

Chemistry

ppm 10 20 40 PTB

DG270 20 12 20 32 F F- 17.85 Ester

DB5951 20 7 12 24 P F + 27.9 Tetrol

DB9392 20 0 9 22 G P 2.49 PEI alkoxylate

DB9947 20 4 16 18 F G 9.17 ResinEO/PO alkoxylate

DRI9037 20 0 10 16 F F 7.68 Polyol

W033 20 3 10 13 G G 29.2 Polyol

DB9393 20 0 0 Tr - - 3.4 Imine ethoxylate

Highest water dropper is DG270. The efficiency reduces down the line. Low salt content is present in DB9393 without any water dropping while DB9392

shows both low salt (2.49) and comparatively higher water dropping (22).

W033 is poor water dropper and high salt, but with good water quality. DB9947 and DRI 9037 show similar behavior in water dropping and salt.

The formulator used DB9947/DB9392/DB9393 (resin alkoxylate /PEI alkoxylate / amine alkoxylate), W033/DB9392/DB9393 (polyols /PEI

alkoxylate / amine alkoxylate), W033/DB9392/DB9392 (polyols /PEI

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alkoxylate /amine ethoxylate) and DB9947/DG270/DB9393 (resin

alkoxylate/ester/amine ethoxylate) as the first four formulations For the final approved selection the following two formulations were

selected.

Formulation

Conc Water dropping

mls/minutes WQ IQ

Top oil water

cut, %

Salt

content

ppm 10 20 40 W1 W2 ∆ PTB

(F1)DB9947/DB9392/DB9393 2/2/1

20 4 6 42 VG G 0 0 0 2.04

(F2)W033/DB9392/DB9393 2/2/1

20 5 12 36 G F+ 0.05 0.05 0 1.29

In formulation F1, water dropping was 42ml, salt content 2.04PTB; top oil

water cut 0%, very good water quality and good interface quality. How was the quantity of dropped water increased to 42? This is the

synergistic effect that helped the formulation to drop more water. The salt content considerably reduced to 2.04PTB, which is due to the

removal of most of the water from the organic layer. The top oil BS&W was

0% which supported the low salt content in the oil layer. In F1 the interface quality was reported as good which supported the very low BS&W (0%).

Coming to F2 water dropping is a little less (36) but salt content was reported as low as 1.29PTB. This shows that F2 needed more time for

flocculating the remaining water which was already separated and hangs in the oil layer. It was evident from the quality of interface which says Fair plus

that means some more time is required for the clearing of interface. It appears a little bit complicated to come out with constructive formulations

that can perform well in bulk trials. Mostly the formulators’ knowledge and experience matters a lot in the conclusion.

Criteria for better performing demulsifier formulation: 1.1. Competent formulator with outstanding chemical knowledge and

experience is a plus point for a formulation. Such formulator can bring out best performing formulation even if the demulsifier bases

are not up to the requirements.

1.2. Well performing demulsifier bases can give very good performing formulations.

Below are given more results from bottle testing which can be evaluated and understood.

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2. Plant 2

Process Data Process Information



Total water cut 68000BD


Temperature at production header 130F

Oil level in separators & dryers 50%


BS&W

Free water 3-5%

Total water 40-45%

Emulsion 35-42%

Demulsifier bases performed with this crude

Demulsifier

Bases


Salt content Chemistry RSN

ppm 10 20 40 PTB

DI937 50 1.5 1.3 5 F F 82.3 Polymeric polyol 7.7

DG270 50 2 2.5 9 F G 76 Modified ester 6.7

D311 50 0.2 7 9 P F 93 Oxylate phenolic resin 18

D3575X 50 4 6.5 8 F F 68.8 Resin ethoxylate 17

D510 50 0 0 0 - - 76 Imine alkoxylate 11

DRI9030 50 0 2 4 F F 70 Ester of phenolic polymer 7-8

DB9429 50 0 2.5 5 G F+ 77.8 Resin alkoxylate 10-14

RS15 50 0 0.5 3 G G 77.8 Alkoxylated resin 12-14

RS19 50 Tr 1 4 F F+ 75 Alkoxylated resin 12

3501X 50 1.8 4 6 F F 75 -

T1301 50 0 4 8 G G 75 - -

W-033 50 0.4 2.5 6 G G 75 Polyol -

DB9955 50 0 2 7 F+ G 75 EO/PO alkoxylate 13-15

Basorol L62 50 0 0.1 1.2 F+ F+ 71 - -

Kemelix-D310 50 0 2 4 F G 72 - -

CB MC238A 50 0.3 0.4 1.0 F F 33 - -

Croda-D300 50 0 0 0.6 F F+ 73 Blend 7-9

DG4283 60 9 10 12 F+ F+ 70.6 Rsin alkoxylate 10.6

D3627X 60 3 7 9 F+ F+ 73 Resin alkoxylate 21

DB9946 60 1.3 9 10 VG G 67 Resin alkoxylate 10-12

SynPE25R2 60 0 2 3 F F+ 56 Polyol alkoxylate 13

DI224 60 0 0.4 1 F F+ 44 - -

DI936 60 4 7 9 F F+ 61 Polyol 8.4


W33/DP188/DB9393 4/1/1 1 42%

DB9947/DG270/DB9393 2/2/1 2 42%

DB9947/DB9392/DB9393 2/2/1 3 42%

DRI9030/D510/DB9393 2/2/1 4 42%

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Formulation



Salt content

ppm 10 20 30 40 W1 W2 ∆ PTB

Incumbent 60 12 18 20 21 F F 13 15 2 44.8

70 16 23 23 24 F F 8 10 2 32.5

W033/DP188/DB9393; 4/1/1

60 16 20 24 26 VG VG 5 5 0 4.37

DB9947/DG270/DB9393; 2/2/1

60 23 24 28 36 G G 0.4 0.4 0 8.26

Evaluation:

In the Plant 2, efficient emulsion breakers are DB9947, DB9393, DB9392 (all from BASF), DP188 (Majorchem), DG270 (Marchem), D510 (Croda),

DRI9030 (Akzo) and W033 (Deshi)

Demulsifier Bases


Salt content

Chemistry RSN

DG270 50 2 2.5 9 F G 76 Modified ester 6.7


DRI9030 50 0 2 4 F F 70 Ester of phenolic polymer 7-8

W-033 50 0.4 2.5 6 G G 75 Polyol -

The formulator has included the formulation from Plant 1 to see their performance. So he has taken corresponding bases from those formulations.

This definitely reduces the time of scanning and formulations. As the salts were found high (in the range of 60-75 PTB) it appears that

more time was required for individual bases to drop more water. The water cut was 45% but maximum water dropped was 12 and formulator did not

consider particular base for formulation. Also the dosage concentration needed was more than 50ppm.

The selected formulations

Formulation



Salt content

ppm 10 20 30 40 W1 W2 ∆ PTB

W033/DP188/DB9393; 4/1/1 60 16 20 24 26 VG VG 5 5 0 4.37

DB9947/DG270/DB9393; 2/2/1 60 23 24 28 36 G G 0.4 0.4 0 8.26

First formulation showed lower water dropping (26ml) while second formulation showed (36ml) higher dropping. But the formulator did not

consider water dropping as the best criteria. First formulation showed very low salt content, 0% top oil BS&W, very good water and interface quality.

Low salt content and 0% BS&W ensure that the emulsion has completely

broken; good water quality and interface quality ensure that there is no over-treat and all the emulsion has broken.

This justifies formulator’s selection considering first formula as best performer.

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It explains that more water dropping is not the criteria for selection.

Ensuring complete emulsion breaking is the criteria for selection of a formula.

3. Plant 3






Temperature at production header 110F(Winter);

150F(summer)


BS&W

Free water 4-16%

Total water 20-34%

Emulsion 4-30%

Demulsifier bases performed better with this crude

Demulsifier Bases



ppm 10 20 40 PTB

DI937 25 1.2 4 5 F F 40.7 Polymeric polyol 7.7

DG270 25 2 7 8 F F 66 Modified ester 6.7

D311 25 2.5 4 5 F F+ 73 Oxylate phenolic resin 18

D3575X 25 4 5 5 G F 62 Resin ethoxylate 17

DB9393 25 Tr Tr Tr - - 40 PEI ethoxylated 6.5

DB9392 25 Tr 1 4 F F+ 73 PIE ethoxylated 8.3


DB9947 25 1 1.8 4 F+ F2+ 69 Resin EO/Po ethoxylate 13

DRI9030 25 3 7 7 F F+ 62 Ester of phenolic polymer 7-8

PG1.5 25 1.2 1.5 4 VG F+ 90 Polyglycol 14

RS15 25 1.6 4 7 F F+ 68 Alkoxylated resin 12-14

D3501X 25 2 3 4 F F 83 -

W-033 25 6 8 9 G G 70 Polyol -

DI936 25 3.5 5 8 F+ F 65 Acrylate polyol 8.4

Basorol K2090 25 Tr 3 5 F+ F+ 68 - -

CB DI910 25 0 0 0 - - 50 - -

DG4283 25 4 5 6 G F+ 68 Resin alkoxylate 10.6

RDM9510 25 4 8 9 F F+ 54 Blend 7-9

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DB9947/DB9392/DB9393 2/2/1 1 37.5%

W033/ DB9392/DB9393 2/2/1 2 37.5%

W033/DG270/DB9393 2/2/1 3 37.5%


Formulation



Salt content

ppm 10 20 30 40 W1 W2 ∆ uS/cm

Incumbent

30 6.5 9.5 12 18 F+ F 0 0.4 0.4 19.84

35 9 14 18 24 G F 0 0.4 0.4 19.45

40 12 17 20 26 F F 0 0.3 0.3 11.29

DB9947/DB9392/DB9393 2/2/1

35 9.5 18 24 30 G G 0 0 0 5.54

W033/ DB9392/DB9393 2/2/1

35 10 14 18 31 VG VG 0.05 0.05 0 5.92

Evaluation: This plant (3) crude oil is similar to Plant 1 crude oil. So most of the

demulsifiers performed in 1 also performed in Plant 3. So the final selected formulation is the same.

4. Plant 4 Process Data

Process Information




Percentage water cut 22%

Water separation in HPPT 10-15 mbd

Temperature at production header 95-115F(W); 135F(S)

Oil level in separators 35%

Oil level dehydrator 50%

Oil level desalter 50%

Salt in crude, average 5-6 PTB

BS&W

Free water 0 – 2%

Total water 24-26%

Emulsion 24-26%

Demulsifier bases performing with this crude

Demulsifier

Bases


WQ IQ

Salt conte

nt Chemistry RSN

ppm 10 20 40 PTB

DI938 30 2 2.5 3 F F 48.9 Polymeric polyol 7.7

DI937 30 1 3 4 F+ F 48 Polymeric polyol 7.6

DG4283 30 2 3 3 F+ F+ 46 Resin alkoxylate 10.6

DB9946 30 0 1 2 G F+ 50 Resin alkoxylate 11

9

D3627X 30 Tr 3 4 F+ F+ 46 Resin alkoxylate 21

D311 30 2 3 4 F F 44.6 Oxylate phenolic resin 18

D3575X 30 3 4 4 F+ F 48.9 Mixed resin ethoxylate 17

DB9393 30 0 0 Tr - - 50 Amine ethoxylate 6.7

DB9947 30 1 1.1 2 F+ F+ 50 Resin EO/PO alkoxylate 13

DRI9037 40 2 4 4 F+ F+ 51 Polyol 7-8

RDM9510 40 2 4 4 F+ F+ 49 Blend 7-9

RS15 40 Tr 1.8 4 F+ F+ 46 Alkoxylated resin 13

DB9392 40 0 0 0 - - 56 PEI alkoxylated 8.3

W033 40 1 3 4 G G 52

3073 40 0.7 1.8 3 F+ F++ 48

DI936 40 1 2 4 F F 55 Acrylic polyol 8.4

DB9904 40 Tr - - - - 44 Tetrol block polymer 11.5


W033/DB9392/DB9393 2/2/1 1 35%

W033/RS15/ DB9393 2/2/1 2 35%

W033/DRI9037/ DB9393 2/2/1 3 35%


Formulation



Salt content

ppm 10 20 30 40 W1 W2 ∆ PTB

Incumbent 60 9 10 12 16 F F 4 4.5 0.5 24.9

W033/DB9392/DB9393;2/2/1 40 9 16 22 22 VG VG 0.05 0.05 0 4.74

W033/RS15/ DB9393;2/2/1 40 10 18 22 22 VG VG 0.1 0.1 0 4.79

W033/DRI9037/ DB9393;2/2/1 40 10 14 17 22 VG VG 0.1 0.15 0.05 6.71

Evaluation: The plant 4 crude oil appears similar to that of 1, 2 and 3. So

the final formulation is similar to that of previous formulations.

5. Plant 5

Process Data

Process Information





Temperature at production header 95-115F(W);

135F(S)


Oil level dehydrator 50%

Oil level desalter 50%


10

BS&W

Free water 0 – 3%

Total water 14-17%

Emulsion 14-16%


Demulsifier Bases

Conc

Water dropping mls/minutes

WQ IQ

Salt content

Chemistry RSN

ppm 10 20 40 PTB

D501 25 0 0.5 1 F+ F 42.7 Polyol 22

D400 25 2 3 3 G F+ 36.7 Ethoxylate phenolic resin 18

PE10100 30 3 4 4 F+ F 48.9 EO/PO Block polymer 20.1

W033 40 0 Tr 2.4 G G - Polyol 10

RS15 40 Tr Tr 0.5 F+ F+ 42.7 Alkoxylated resin 13

L62 40 0 Tr 0.3 G G 42 -

CB-AP954 40 0 0.1 1.0 G G 40 -

D401 40 0 0.1 0.4 F+ F+ 43 -

D3424X 40 0 0.2 0.5 F+ F+ 42 -

DB9954A 50 0 1 1 F+ F+ 47 Resin alkoxylate 11

DRI9037 30 Tr Tr 0.2 F+ F+ 40 Polymeric Polyol 7-8


Formulation


WQ IQ

Top oil water cut, % Salt content

ppm 10 20 30 40 W1 W2 ∆ PTB

Incumbent

70 3 4.5 5 6 F+ F+ 12 12 0 43.5

75 3.1 4.8 5 6 F+ F+ 12 12 0 45

W033/D501/DRI9037

(1/2/1) with 10% (H

Acid)

60 2 4.8 7 8 VG G 11 11 0 33.8

Evaluation

The demulsifier bases that worked in this crude oil were very limited; a maximum of 57% water was dropped with the formulation. All the three

bases in this formulation were polyols from different suppliers - D501 (polyol RSN 22), W033 (polyol RSN 10), DRI9037 (polyol RSN 7-8). As the RSN

differs each of them works at different solvent conditions. Most of the time polyols appear as assisting demulsification rather than actual main emulsion

breaker. So there is a lack of competent emulsion breaker in the list of demulsifiers that were used for screening this crude oil emulsion. The H-acid

was used here to clarify both water quality and improve interface quality. Need of a highly branched flocculant demulsifier is lacking in this testing

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6. Plant 6

Process Data

Process Information





Temperature at production header 110-120F(W); 135F(S)


Oil level in dehydrator/desalter 50%


Water cut

Free water 2– 4%

Total water 16-18%

Emulsion 12-16%


Demulsifier

Bases

Conc

Water dropping mls/minutes

WQ IQ

Salt conte

nt Chemistry RSN

ppm 10 20 40 uS/cm

D501 35 Tr 1.8 2 F+ F 29.2 Polyol 22

DB9393 35 Tr 1 2 F F 24.2 Amine ethoxylate 6.5

D311 35 0 0 0 - - 37 Oxylated phenolic resin 18

W033 35 1 2.5 3 F G 32 Polyol 16

RS15 35 3 Tr 0.5 F+ F+ 42.7 Alkoxylated resin 13

DRI9037 35 Tr Tr 1 F F 30 Polymeric Polyol 7-8

CBDI950 35 0 1 2 P P 33 Polyol 8

DI937 35 0 0.1 0.4 F+ F+ 34.6 Polymerized polyol 7.6

CB 461 35 Tr 1 1.5 F+ F+ 32 NPR rsin alkoxylate 12.5

CBRO510 35 0.6 1.8 2 P F 33.7 Resin alkoxylate 20

DI945 35 0 1 2 F F 30.7 Amine oxyalkylate 16

DG4283 35 0.5 3 3 G F 32.7 Resin alkoxylate 10.6

D3575X 35 1 2 3 G F 29.4 Modified resin ethoxylate 17

D3627X 35 1 1.5 1.5 F F 30 Resin alkoxylate 21

D3535X 35 1 2 3 F F 32 APF resin ethoxylate 17

DB9946 35 1.5 1.8 2.5 F F 28.2 Resin alkoxylate 11

DB9947 35 1 2 2 F F 29 Resin (EO/PO) alkoxylate 13

DB9955 35 1.5 3 3 F F 28 Resin alkoxylate EO/PO 14

PE6400 35 1 1.5 1.8 F F 29 EO/PO block 20.1

DP-188 35 0.8 1 2 F F 26 Polyol 16

DB9942 35 Tr 2 3 F F 44 Resin alkoxylate 8-9

DRC232 35 0.5 1 4 F F 40 Resin alkoxylate 14.3

DPG482 35 0.5 1 2.8 F F 44 Polyglycol 18.8

DB9429 35 Tr 1 2.8 F F - Resin alkoxylate 10-14

DE-E5 35 Tr 1 1.2 F F 26 Amine alkoxylated 6

DRI9045 35 1.2 1.8 2 F F 40 -

CB361 35 1 2 2 F F 42 NPF EO/PO -

DRC168 35 0 2 2 F F 44 -

RS11 35 Tr 1.8 2 F F 40 Alkoxylated resin 17

L101 35 0 1 1.6 F F 39 -

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Formulation



Salt content

ppm 10 20 30 40 W1 W2 ∆ PTB

Incumbent 50 7 9 9 10 F+ F- 3 3.5 0.5 14.71

W033/DP188/DB939 (2/1/1)

40 7 10 13 15.5 G G 0.6 0.6 0 9.73

RS15/DEE5/DB9393 (2/1/1)

40 4 10 13 14 G G 0.2 0.2 0 8.97

Evaluation: The crude oil feed for this plant different in its behavior

compared to 1, 2, 3, and 5. The water cut in this crude oil emulsion is 16-18% so the expected water dropping was around 11-12 ml from 100ml

sample, taking in to account of an average dropping of 70% emulsion

breaking. But the highest amount of water dropped is just free water. The screen test did not support the formulator with good information. The

salt test also did not support with good information. So the formulator depended on synergism.

The final formulations selected were W033/DP188/DB9393 and RS15/DEE5/DB9393. The formulator reached at these formulations after a

number of tests. W033 and DP188 are polyols, DB9393 and DEE5 are imine alkoxylates and

RS15 is a resin alkoxylate. Polyol with imine alkoxylate synergism (F1) dropped almost 92% water in

the emulsion. Salt content reduced to 9PTB and top oil BS&W 0% with a 0.6% suspended water.

Resin with imine alkoxylates synergism dropped 85% water, salt content reduced to 9PTB and top oil BS&W 0% with suspended water of 0.2%

The study of synergism was explained in the following article shown in

Linkedin slideshare:” Review of demulsifier bottle testing procedure” by the same author.

7. Plant 7





Percentage water cut 46%

Temperature at production header 108F(W); 150F(S)



BS&W

13

Free water 50– 56%

Total water 50-56%

Emulsion 0-2%


Demulsifier Bases



ppm 10 20 40 PTB

DG270 15 24 32 34 G G 51.4 Modified ester 6.7

DB9393 15 Tr 0.2 7 G F+ 4.32 Amine ethoxylate 6.7

DI945 15 11 12 20 VG G 81.2 Amine oxyalkylate 16

D3575X 15 12 18 19 F+ F+ 120 Modified resin ethoxylate 17

DE E5 15 0 6 33 F F+ 6.32 Polyethylene amine alkoxy 6

D3422X 15 1.5 5 36 F+ F+ 3.86 Polyimine alkoxylate 8

DEPA10 15 8 12 22 F+ F+ 5.78 Polyethylene imine alkoxy 9-10

DB9390 15 7 14 27 VG G 5.88 PEI alkoxylate


DB9360 15 3 6 10 VG G 17 PEI alkoxylate -

DRI9037 15 4 10 18 F+ F + 22 Polymeric Polyol 7-8

DI936 15 3 10 20 F F 32 Acrylic polyol 8.4

DB9904 15 10 20 26 G F 73 Tetrol 11-12

DP188 15 1 18 42 VG F+ 3.78 Polyol 16

DG4283 15 10 14 15 F+ F 98 Resin alkoxylate 10.6

DB9947 15 13 16 24 VG G 95 Resin EO/PO alkoxylate 13

RDI3124 15 8 12 16 F G 123 Resin oxyalkylate 13.9

DR19030 15 2 8 19 F+ F 5.85 Ester phenolic polymer 7-8

DRM9510 15 3 9 14 F+ F+ 40 Blend 7.9

DRC232 15 12 18 21 F G 88 Oxylated resin 14.3

CB361 15 4 10 15 F+ F 104 NPF EO/PO -


Formulation



Salt content

ppm 5 10 20 30 40 60 W1 W2 ∆ uS/cm

Incumbent 11 22 28 36 43 48 52 VG F 0.3 0.4 0.1 28.1

DI945/D3422X/CB9393

(2/2/1), F1

15 20 28 39 48 51 54 VG G 0.1 0.2 0.1 7.95

D3575X/DRM9510/DB9393 (2/1/1), F2

15 20 28 35 43 50 52 F G 0.15 0.2 0.05 9.55

D3575X/DI936/DB9393 (1/2/1), F3

15 20 36 48 50 50 52 F G 0.1 0.2 0.1 9.79

Evaluation: The water cut in this plant is 50-56%.better performers are:

Demulsifier Bases



ppm 10 20 40 PTB

DG270 15 24 32 34 G G 51.4 Modified ester 6.7

D3422X 15 1.5 5 36 F+ F+ 3.86 Polyimine alkoxylate 8


DP188 15 1 18 42 VG F+ 3.78 Polyol 16

DE E5 15 0 6 33 F F+ 6.32 Polyethylene amine alkoxy 6

14

Evaluation:

In the final formulation the bases used were much different, may be the reproducibility of performance lost or not found in the subsequent tests,

which were not presented here by the formulator. The final formulations show good water dropping, low salt content, low top

oil BS&W, good water quality (F1) and interface quality. DI945 (amine alkoxylate), D3422X (amine alkoxylate), CB9393 (resin

alkoxylate), D3475X (resin alkoxylate), DRM9510 (blend formulation), DI936( polyol) and DB9393 (amine alkoxylate) are the selected bases for

the final formulation Here amine alkoxyalte and resin alkoxylate are the blend of formulation, F1

ad F2, and polyol and amine alkoxylate are the blends of F3 formulation.

Formulation



Salt content

ppm 5 10 20 30 40 60 W1 W2 ∆ uS/cm

DI945/D3422X/CB9393 (2/2/1), F1

15 20 28 39 48 51 54 VG G 0.1 0.2 0.1 7.95

Plant crude oils and selected demulsifier blends

Plant crude oil

Slected demulsifier blends

1 2 3

Plant1 Resin alkoxylate/amine alkoxylate

Polyol/amine alkoxylate

Plant 2 Resin alkoxylate/amine

alkoxylate

Polyol/ester/amine

alkoxylate

Plant 3 Resin alkoxylate/amine alkoxylate

Polyol alkoxylate/amine alkoxylate

Plant 4 Resin alkoxylate/ amine alkoxylate

Polyol/resin alkoxylate/amine

alkoxylate


Plant 5 Polyol (RSN22)/polyol (RSN 10)/polyol (RSN 7.5) with sulfonate acid

Plant 6 Polyol/amine alkoxylate Resin alkoxylate/amine alkoxylate

Plant 7 Resin alkoxylate/amine alkoxylate


From above data for all gas oil separating plants the demulsifier formulations that performed well in bottle tests (also in subsequent field trials) are blends

of resin alkoxylates/amine alkoxylate and polyol/amine alkoxylates. In some cases resin alkoxylate/polyol/amine alkoxylate blend was also working.

Esters give added advantage to the blends. Polyols are usually EO/PO co-polymers with multiple hydroxyl end groups.

The hydroxyl end groups usually extend to water droplets of medium sized

15

emulsions. Esters are also hydroxyl containing polymers which associate

with water by hydrogen bonding.

Amine/imine alkoxylates with their extended network functions as treaters that can break even small micro emulsions. The nitrogen in amines like

oxygen in polyols can develop different types of association with water molecules using Vander Waals forces.

The general concept is that nitrogen and oxygen containing polymers with net work character can break the water-in oil emulsion and flocculate.

Giants in fossil fuels

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Iranian oil The demulsifier formulations were developed for GOSPs having crude oils with API gravity in the range 16-25. The crude oil appeared to contain more

asphaltene and very viscous and sticky in nature. The total retention time was 16-24 hours which shows bottle test result conclusion may be time

consuming if replicated plant retention time. So the tests were restricted with 1 hour retention time for bottle testing. As the incumbent samples were

also tested along with that of vendor’s demulsifiers, the results can be

comparable. The dry crude oil specification was - salt content < 10PTB, and water (BS&W) <0.5%. As the crude oil was sticky the demulsifiers were

dosed at 60oC to have good mixing and distribution.

1. Plant 1

Process Data:

Process Information

Quantity Unit

Production Rate 73000bd MBD

Wash Water 3650bd BD

Salt inlet 5120 ppm

Free Water inlet 0.8 %

Specification

Salt Outlet 33 ppm

Water Outlet 0.025 %

Screening

S No Formula Ratio Conc. (ppm)

Water dropping

Quality Top oil water cut, %

Salt content

PTB W IF

1 Incumbent -1 --- 100 0 --- --- 2.2 18.1

2 Incumbent-2 --- 100 Tr --- --- 2.0 22.2

3 Incumbent- --- 100 0 --- --- 2.1 21.6

4 Vender 1 --- 100 Tr --- --- 2.1 21.5

5 D309 --- 100 6.5 G G 1.0 8.0

6 DB2903 --- 100 Tr --- --- 3.6 14.0

7 DB9955 --- 100 1 G F 3.4 13.8

8 DB9955/D510 1:1 100 1.5 G G 0.2 9.4

9 DB9955:DB2903:D510 1:1:1 100 1.3 VG G 1.7 12.8

10 D309:DB5914:D510 1:2:1 50 3 G F 1.4 12.0

11 D309:DB5914:D510 2:1:1 50 2 G F 1.5 12.5

12 D309:DB5914:DB9393 1:1:1 50 1 VG F 1.9 14.2

13 D309:DB5914:DI938 2:1:1 50 2 VG P 1.4 12.5

Final selection

S No

Formula Ratio Conc. (ppm)

Water dropping

WQ IQ Top oil water cut,

%

Salt content PTB

1 D309:DB5914:DI938 2:1:1 50 6 G F 1.0 6.53

2 D309:DB5914:DI938 1:2:1 50 8 G F 1.0 4.0

3 Incumbent -1 --- 150 4 G F 1.4 9.9

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Evaluation:

The better performed demulsifier bases are given the table with final formulations. D309 was found good water dropper for this crude emulsion.

The final formulations were with D309, DB5914 and DI938 Demulsifier base-supplier Chemistry RSN

D309-Croda Ethoxylated phenolic resin 21

DB5914-BASF Tetrol EO/PO 39

DI938-Marchem Polymeric polyol 7.7

In this formulation, the demulsifier with RSN7.7 can remain in the organic

layer, while demulsifiers with RSN 21 and 39 can quickly move towards emulsion and thus to water. But dosing demulsifier with higher RSN is a

negative mark for this formulation which may result in the poor performance of demulsifier while the needed dosage injection can go up during the

emulsion breaking process. This shows that bottle test conclusion was not complete with the given

timings and available demulsifier bases. In the laboratory the vendor’s formulation did better performance than

incumbent even at low dosage with high water dropping, salt content and water quality. The interface was not sharp as required. The top oil WS&W

was above requirement even though much better than incumbent.

2. Plant 2 Process Data

Process information

Quantity Unit

Production Rate 112000 BD

Wash Water 4480 BD

Salt inlet 12690 ppm


Specification

Salt Outlet 28 ppm


Demulsifiers and formulation that performed well

S

No Formula Ratio

Conc.

(ppm)

Water

dropping

Quality Top oil

water

cut,%

Salt

content

PTB w IF

1 Incumbent --- 100 0.8 F F 0.07 3.1

2 Vendor 1 --- 100 0.5 G F 0.1 3.5

3 Vendor 2 --- 100 0.5 G F 0.15 3.6

4 Vendor 3 --- 100 0.5 G F 0.05 2.2

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5 D309 --- 100 2.8 G F 0 4.7

6 DI938:D309:DB9393 3:0.25:1 100 2.2 F P 0.1 6.7

7 DB9955: D510 1:1 50 1.2 G G 0 1.6

8 DB9955:D309:D510 1:1:1 50 1.2 VG G 0 0.7

9 DB9955:D309:DB9393 1:1:1 50 1.6 VG F 0 0.7

Final selection

S No


Water dropping

WQ IQ Top oil water cut,%

Salt content

PTB

1 Incumbent 150 38 G G 0 6.7

2 Vendor 1 250 36 G G 0 7.0

3 DB9955:D309:DB9393 1:1:1 100 38 G F 0 2.5

Evaluation:

The final formulation in Plant 2 is a blend of DB9955 D309 and DB9393 Demulsifier base-supplier Chemistry RSN


DB9955-BASF Resin alkoxylate 13.5-15.5

DB9393-BASF Amine alkoxylate 6.7

Two resin alkoxylates were blended with amine alkoxylate. RSN range shows

a complete distribution from oil to emulsion to water level. Water dropping by this formulation at a lower dosage was better with very

good low salt content and top oil BS&W. Water quality for this formulation was good while interface quality was satisfactory.

3. Plant 3

Process data Process Information

Quantity Unit

Production Rate 112 MBD

Wash Water 4480 BD

Salt inlet 12690 ppm


Salt Outlet 28 ppm


Demulsifier formulations:

S No Formula Ratio Conc. (ppm)

Water dropping

Quality Top oil

water cut

Salt

content (µS/cm) W IF

1 Incumbent --- 200 0.5 P F 0.8 15.1

2 Vendor 1 --- 200 1.2 P G 0.8 17.6

3 D309 --- 100 0.8 P G 0.8 16.8

4 DB9955 : D510 1:1 100 1.2 P G 0.6 18.9

5 DB9955:DB2903:D510 1:1:1 100 1.2 F G 0.8 18.7

6 DB9955:D309:DB9393 1:1:1 100 0.6 P G 0.8 14.9

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Final selection

S No


Water dropping

Quality Top oil water cut

Salt content (µS/cm) W IF

1 Incumbent -1 --- 150 0.8 F G 0.4 10.3

2 DB9955:DB2903:D510,F1 1:1:1 75 1.2 F G 0.3 8.4

1 Incumbent -2 --- 150 1.0 F G 0.1 2.5

2 DB9955:DB2903:D510,F2 1:1:1 75 1.0 F G 0.4 10.5

1 Incumbent -3 --- 150 3.0 F G 0.2 1.9

2 D309:DB5914:DB9393,F3 2:1:1 75 2.1 F G 0.4 6.6

3 D309:DB5914:DB9393 1:2:1 75 2.0 F G 0.3 5.5

Evaluation: There were three flows to be evaluated for the different incumbent

formulations. The selected demulsifier bases have the following chemistry. Demulsifier base-supplier Chemistry RSN


DB9955-BASF Resin alkoxylate 13.5-15.5

DB9393-BASF Amine alkoxylate 6.7

DB2903-BASF EO/PO block polymer 23

DB5914-BASF Tetrol 39-45

D510-Croda APF resin alkoxyate 8

F1&F2: DB9955(RSN:14)/DB2903(RSN:23)/D510(RSN:8):resin alkoylate/

EO-PO polymer/Resin alkoxylate This formulation is more weighed towards water soluble area. But presence

of D510 in the oil layer can support more emulsion breaking F3: D309 (RSN: 21) /DB5914 (RSN: 40) /DB9393 (RSN: 6.7) phenolic

resin/tetrol/amine alkoxylate This formulation has amine alkoxylate which can break small emulsions.

Crude oils and demulsifier formulations

Plant Selected formulations

Plant1 Resin alkoxylate/tetrol/polyol

Plant 2 Resin alkoxylate/resin alkoxylate/amine alkoxylate

Plant3-1&2 Resin alkoxylate/block polymer

Plant 3 -3 Resin alkoxylate/tetrol/amine alkoxylate

The general formulation for all these crude oil can be considered as resin alkoxylate and polyol (tetrol and EO/PO polymers are polyols by nature).

Second formulation is resin alkoxylate with amine alkoxylate. Third one is

resin alkoxylate, polyol and amine alkoxylate.

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Comparison of demulsifier formulations: Saudi oil & Iranian oil

Type Saudi oil Iran oil

1 Resin alkoxylate/amine alkoxylate Resin alkoxylate/amine alkoxylate

2 Resin alkoxylate/polyol Resin alkoxylate /polyol

3 Resin alkoxylate/polyol/amine alkoxylate

Resin alkoxylate/polyol/amine alkoxylate

4 Polyol/amine alkoxylate NA

5 Polyol/ester/amine alkoxylate NA

6 Polyols with RSN ranging from oil solubility to water solubility

NA

As concluded above combination of resin alkoxylate with amine alkoxylate,

resin alkoxylate with polyols and combination of all three types are the general formulation that works in both oils.

The above conclusions are based on the available data. There are other types of demulsifiers with different chemistry (diepoxides, PU demulsifiers,

ether polyols, vegetable oil based demulsifiers, sorbitan and starch based demulsifiers, silicone based demulsifiers, etc...). Further testing and

screening with all types of demulsifiers may give more specific and high

performing formulations.

demulsifiers water in oil emulsion separation results

Technology