production chemistry cims pc 1.0

CIMSPRODUCTIONCHEMISTRY

Abu Dhabi Company for onshore oil operations

PRODUCTION CHEMISTRY - CIMS-PC-1.0

Table of ContentsPage No.

Contents i

Process Overview Flowchart ii

1.0 Introduction 1

2.0 Scope 1

3.0 References 23.1 References 2

3.2 Definitions 2

4.0 Health, Safety and the Environment 3

5.0 Procedure 3

5.1 Identify Task 3

5.2 Sampling Frequency 4

5.3 Obtain Sample 4

5.4 Analytical Method 5

5.5 Analytical Results 5

5.6 Repeat Testing 5

5.7 Results Analysis 6

5.8 Further Action 6

Attachments

1. Crude Oil Analysis Methods - Routine Quality Control Tests Guidelines 7

2. Determination of Salt, Sediment and Water in Crude Oil Samples 9

3. Determination of Dissolved Hydrogen Sulphide in Crude Oil Samples 11

4. Gas Analysis Methods - Routine Quality Control Tests Guidelines 12

5. Determination of Hydrogen Sulphide Content in Gas - Tutweiler Method 13

6. Determination of H2S and CO2 Content in Gas - Orsat Method 17

7. Water Analysis Methods- Routine Quality Control Tests Guidelines 20

8. Determination of Oil-In-Water by I.R. Absorption 23

9. Oilfield Scale Analysis 24

10. EPA (USA) Laboratory Test Methods for Environmental Sampling 33

11. Production Chemistry Data Records 36

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1.0 INTRODUCTION

This document contains guidelines, methods and references to be followed in the management of routine production chemistry activities. Where the method or guideline for an activity is standardised within ADCO or follows a recognised standard, then the standard, standard type and identification code is referenced.

Production Chemistry activities entail the acquisition of samples from appropriate locations and analysing to produce results which provide:

(a) product quality control for export oil;

(b) information to monitor plant performance;

(c) information to monitor corrosion mitigation programmes;

(d) data to ensure that potable water is of acceptable quality;

(e) data to monitor the effect of effluents on the environment;

(f) injection water quality;

(g) reservoir performance.

2.0 SCOPE

This document is intended to cover all routine Production Chemistry activities performed in ADCO Fields/Terminal.

It primarily includes analysis of :

Produced and injected fluids - Oil

- Gas

- Produced (formation) water

- Injection (aquifer / brackish) water

Utility fluids - Potable water

- SCAD wash water

- Lube oil

- Glycol

Effluent - Disposal Water

- Industrial waste

Scale/Solids - Corrosion products

- Mineral scales/deposits

- Sludge

Special methods developed for temporary or unusual circumstances are not included within this scope.

3.03.1 References

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The user must confirm with ADCO Engineering Technical Library that the latest revision is being used before consulting a referenced document.

Laboratory Methods

ASTM, Book of ASTM Standards, Part 31, Volume O5.02

ASTM, Manual on Water, STP 442

American Gas Chemical Handbook, 3rd Ed. 4662, Chemical Publishing Co., New York (1929)

API RP 44, Recommended Practice for Sampling Reservoir Fluids

C. W. Lapham., "Chemistry", GCE O-Level Passbook.

Carel & Wimberley., "Dissolution Analysis Improves Oil Field Scale Treatment", OIL & GAS Journal, Jan 14, 1991.

Flopetrol, "Chemical Methods to Determine the Composition of Scale Samples".

Gershon J. Shugar & John A. Dean., "The Chemist's Ready Reference Handbook", McGraw-Hill, Inc., 1990.

John Kenkel., "Analytical Chemistry for Technicians", 2nd Ed., Lewis, 1994.

Tutweiler, C.C. J. American Chemical Society, 23, 173 (1901)

Vogel., "Quantitative Inorganic Analysis", 4th Ed., Longman, 1981.

Other Related CIMS Procedure

CIMS-IS-4.0 Sample Cylinder Inspection

Further references used for this procedure are listed against the analytical methods contained in Attachments 1, 4, 7 and 10.

3.2 Definitions

C & I - ADCO’s Corrosion & Inspection Section for a Field or Terminal

CDS - Central Degassing Station

ELF - Extraction Loss Factor

EPA - Environmental Protection Agency

eq. - Equivalent

IR - Infrared

mg/l - Milligram per litre, one-thousandth (0.001) of a gram per litre

MOL - Main Oil Line

mol - The amount of a substance that has a weight in grams equal to the molecular weight of the substance.

ppm - Part per million

RDMS - Record Data Management System for ADCO CIMS

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RDS - Remote Degassing Station

SCAD - Salt Control and Dehydration

SRB - Sulphate Reducing Bacteria

4.0 HEALTH, SAFETY AND THE ENVIRONMENT

All activities outlined in this procedure must be performed in line with ADCO’s policy (latest issue) on health, safety and environment (HSE). The ADCO Procedure Manual No. 10 - Safety shall be consulted prior to the performance of any of the activities outlined within this procedure.

In addition to the above document, any person undertaking a sampling, analytical or related activity should also consult and follow the manufacturer’s information for any product, chemical or item of equipment to be used. Any recommendations made concerning the use of protective clothing shall be followed.

5.0 PROCEDURE

The Production Chemistry Overview Process Flowchart links the key tasks in the procedure for the performance of any Production Chemistry activity.The required information which relates to the performance can be obtained from the methods referenced in Attachments 1, 4, 7 and 10.

5.1 Identify Task

The first stage in the performance of a Production Chemistry activity is to identify the task required at that instant. It is dictated by the data required and assigned frequency of that task.

The intent is to determine:

- what process or utility fluid to sample

- where to obtain a sample

- information to be derived

There are three categories of tests for oil, gas and water:

Routine quality control (QC) tests which are routine tests required for monitoring the operations of Fields, Plants or Terminal with reference to product specification requirements.

Analysis designed to enhance understanding of the system and delineate process changes.

Non-routine, comprehensive or special analysis, where further additional tests are required for specialised investigations or projects.

Oil tests are performed for wells, RDS, CDS, SCAD units, MOLs and tanker export. Gas tests are required for fuel gas, injection gas and sales gas. Water tests are performed for produced (formation) water, disposal water, injection water, potable water and wash water.

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5.2 Sampling Frequency

The frequency of sampling or performing tests is dependent upon the category or type of test, the fluid or material being tested and the requirements for results interpretation or analysis. The quality control or routine tests have been assigned recommended frequency guidelines which are listed in Attachments 1, 4 and 7. Adjustments to the repeat frequency for quality control tests may arise from changes in production practices or where analysis/interpretation of results indicates that the testing frequency is inappropriate.

5.3 Obtain Sample

Systems requiring sampling are listed in Attachments 1, 4 and 7. The required information relating to quantity and treatment of sample prior to laboratory analysis may be sourced from the test methods which are referenced in Attachments 1, 4, 7 and 10.

Information relating to the inspection and storage of sample containers shall be obtained from the Sample Cylinder Inspection Procedure, CIMS-IS-4.0.

5.4 Analytical Method

The following is a summary of this procedure’s attachments which address the various test methods:

5.5 Analytical Results

The results from the oil, water, gas or scale analysis shall be entered in the appropriate section (routine quality control test or system information

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Attachment Topic

Oil 1 Crude Oil Analysis Methods - Routine Quality Control Test Guidelines

Oil 2 Determination of Salt, Sediment and Water in Crude Oil Samples

Oil 3 Determination of Dissolved Hydrogen Sulphide in Crude Oil Samples

Gas 4 Gas Analysis Methods - Routine Quality Control Test Guidelines

Gas 5 Determination of Hydrogen Sulphide Content in Gas - Tutweiler Method

Gas 6 Determination of H2S and CO2 Content in Gas - Orsat Method

Water 7 Water Analysis Methods - Routine Quality Control Test Guidelines

Water 8 Determination of Oil-in-Water by I.R. Absorption

Scale 9 Oilfield Scale Analysis

Other 10 EPA (USA)Laboratory Test Methods for Environmental Sampling

RDMS 11 Production Chemistry Data Records


Analysis Test) of the RDMS system, which shall also reference the method. Refer to Attachment 11.

5.6 Repeat Testing

Each system (eg MOL, Terminal export loading lines, injection water, etc.) has acceptance criteria. If an acceptance criterion for any item is out of specification, the following retesting sequence should be undertaken to verify the validity of the test results:

1. Rerun the test twice on the same sample. If the two follow-up tests meet the acceptance criteria, use the average value of the two acceptable tests and discard the first test’s results as a probable short excursions, laboratory or sampling technique errors.

2. If the two follow-up tests do not meet the criteria, record their average and consult with the appropriate Field/Terminal Supervisor for further action. Refer to Section 5.8.

5.7 Results Analysis

It is necessary to utilise trending and other data analysis tools in order to provide useful information towards the control of the related activity e.g.:

- chemical injection regimes

- corrosion mitigation activities

- process control requirements

- effect of process modifications

- establish analysis frequency

5.8 Further Action

Further action may be required which may involve a modification to the process parameters or actions by an authority who is not directly responsible for the performance of the Production Chemistry tasks. The relevant authority shall be advised of the pertinent sections of the results analysis and the recommended modification/actions.

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ATTACHMENT 1 (Page 1 of 2)(Sections 5.2, 5.3 & 5.4)

CRUDE OIL ANALYSIS METHODSROUTINE QUALITY CONTROL TEST GUIDELINES

Sample Frequency

Test ReferenceWells RDS TL CDS (Inlet) SCAD Units Field MOL Inlet Terminal MOL

Inlets

API Gravity and Density

ASTM D-1298 Q Q W D 3/D

BS & W (% volume)

Attachment 2 - Method A

Q/M Q W W 2/D 3/D

Salt (ptb) Attachment 2 - Method B or IP - 265

Q Q W W 2/D 3/D

H2S (ppm) Attachment 3 Q Q Q W 3/D

Reid Vapour Pressure (psi)

IP - 69 - - - - - 3/D

Water (% volume)

ASTM D-4006 - - - - 3/D

Frequency: D - Daily Q - Quarterly

W - Weekly A - Annually or possibly Non-routine

M - Monthly 2/D - Twice per Day

3/D - Three Times per Day

Note: Use ASTM D-270 as a crude oil sampling method reference.

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ATTACHMENT 1 (Page 2 of 2)(Sections 5.2, 5.3 & 5.4)

NON-ROUTINE ANALYSIS METHODS

Table 1-1: Non-Routine Oil Analysis Methods

Test Methods

Acidity, total

(mg KOH/gm)

IP - 1

IP - 139

Ash (% wt) IP - 4

Asphaltenes (% wt) IP - 143

Carbon Residue (% wt) IP - 13

Flash Point (oF) IP - 170

Pour Point (oF) IP - 15

Sediment by Extraction (% wt) IP - 53

Sulphur (% wt) IP - 61 or ASTM D 129

Ni (ppm) IP - 285

V (ppm) IP - 285

Viscosity ASTM D 445

Wax (% wt) UOP - 460/64

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PRODUCTION CHEMISTRY - CIMS-PC-1.0ATTACHMENT 2 (page 1 of 2)(Section 5.4)

DETERMINATION OF SALT, SEDIMENT AND WATERIN CRUDE OIL SAMPLES

Method-A: Determination of Sediment and Water

A:1.0 Procedure

If the crude sample does not contain free water, skip to step 1.7.

1.1 To the original crude sample, containing free water, add 0.5-1.0 ml demulsifier solution prepared as per note (1).

1.2. Agitate the sample 5 times by hand.

1.3. Immerse the glass sample bottle in water bath (60 Cº) and leave it for adequate time to settle the free water.

1.4. Transfer the sample quantitatively to a measuring cylinder, measure the sample total volume accurately and record it as (TV).

1.5. Transfer the sample to a separating funnel. After the lower water layer has a clear cut, draw off as much water as available into measuring cylinder. Read water volume, record as (FW) and keep aside for testing salt content in METHOD-B.

1.6. Transfer the remaining crude to the same sample bottle.

1.7. Shake the sample bottle for 10 minutes in the shaking machine, then shake it by hand vigorously about 10 times.

1.8. Using only a single centrifuge tube each sample, follow the steps (8.1 - 8.8) in ASTM

D 4007* (Note 2).

1.9. Read and record water (W) and sediment (S) volume to nearest 0.05 ml.

A:2.0 Calculations

2.1 Sediment % = S x 2

2.2 Water % (EW) = W x 2 (for samples without free water)

2.3 Water % (TW) = (for

samples with free water)

Where,S = Sediment reading (step A:1.9)W = Water cut reading (step A:1.9)FW = Water cut reading (step 1.5 )TV = Sample volume (step 1.4 )

A:3.0 Notes

(1) 10% (V/V) demulsifier solution should be prepared using oil-soluble type, like RP-6025 or EMO-507, diluted in pure toluene.

(2) All apparatus and reagents as per ASTM D 4007 specification.

* 1995 ANNUAL BOOK of ASTM STANDARDS, Vol 05.02

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PRODUCTION CHEMISTRY - CIMS-PC-1.0ATTACHMENT 2 (Page 2 of 2)(Section 5.4)

DETERMINATION OF SALT, SEDIMENT AND WATERIN CRUDE OIL SAMPLES

Method-B: Determination of Salt Content (and Chloride in Associated Water)

B:1.0 Procedure:

1.1 If the crude sample contains free water, pipette exactly 1.0, 0.5 or 0.25 ml (V) from the separated water in step A.1.5. (METHOD-A), transfer into a titration flask and make volume up to 50 ml with de-ionised water, Skip to step 1.9.

1.2 If the crude sample does not contain free water, shake crude sample for 10 minutes in the shaking machine followed by 10 times shaking by hand vigorously.

1.3 Using a measuring cylinder, measure 100 ml of sample and transfer it to another shaking glass bottle contains 0.5 ml of demulsifier solution prepared as per note 1 in method A.

1.4 Wash the cylinder with exactly 100 ml de-ionised water and add the washing to the shaking bottle.

1.5 Shake the oil-water mixture on the shaking machine for 10 minutes.

1.6 Transfer the mixture quantitatively to a separating funnel and allow the phases to separate.

1.7 Draw off more than 50 ml of the lower extract into a beaker.

1.8 Pipette an appropriate volume (C) of the extract (50, 25, 10 or 5 ml), depending on sample salinity, into a titration flask and fill, if necessary, up to 50 ml with de-ionised water.

1.9 Bring the flask content to boil, test the vapours for hydrogen sulphide with lead acetate paper until getting a negative result. Cool and rinse inner wall of the flask with de-ionised water.

1.10. Check the pH of the flask content with pH paper. Neutralise pH, if necessary, with (0.1 N) NaOH or HNO3 to reach neutral or slightly alkaline.

1.11 Add 1 ml of Potassium Chromate (5%) indicator solution then titrate with (0.1 N) AgNO3 solution to changed-color endpoint, (from lemon-yellow to reddish orange).

1.12 Read and record titrant, ml. (A)

B:2.0 Calculations

For samples with free water:

2.1 Chloride, mg/l =

2.2 Salt content, ptb =

For samples without free water:

2.3 Salt content, ptb =

2.4 Chloride, mg/l =

Where,A = Titrant volume, ml (step B:1.12).C = Volume of pipetted extract, ml (step B:1.8).EW = Water percentage of the sample, % (step A:2.2).TW = Water percentage of sample, % (step A:2.3)V = Volume of aliquot, ml (step B:1.1)

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ATTACHMENT 3(Section 5.4)

DETERMINATION OF DISSOLVED HYDROGEN SULPHIDE IN CRUDE OIL SAMPLES

Procedure:

1. To 100 ml. of crude oil in a separating funnel add 150 ml of 3% Borax solution.

2. Immediately replace the stopper in the separating funnel and invert the funnel 50 times - inversions should be fairly vigorous but short of shaking.

3. Leave standing for 10 minutes. The aqueous extract should be clearly separated from the oil.

4. Run off 10 ml of the extract and discard.

5. Run off 10 ml of the extract into a glass stoppered Conical flask.

6. Add a few drops of Phenolphthalein indicator and titrate with 1.5% solution of Sulphuric Acid until the pink colour disappears.

7. Dilute the mixture to an approximate volume of 30 ml with distilled water.

8. Add to the mixture 4 ml of Dithizone indicator. (A very diluted solution in Chloroform.)

9. Case No. 1: Titrate with the standard (0.01 N) Mercuric Chloride solution. Remember you must shake the stoppered flask vigorously after each addition of titrating reagent. Continue this until the colour of the mixture changes from green to yellow-orange.

10. Case No. 2: Should, during the titration, severe cloudiness develop, discard the sample and repeat starting from Step No. 5, but take 5 ml aliquot sample for titration instead of 10 ml.

11. Case No. 3: If severe cloudiness develops again, discard this sample also and repeat from Step No. 1 but use 200 ml of Borax solution, 50 ml of oil sample and take 5 ml of aliquot sample for titration.

12. When testing for H2S concentration in crude taken directly from production wells or prior to stripping, then use 200 ml of Borax solution and 25 ml of crude oil sample and proceed as directed above taking 5 ml aliquot from the aqueous extract for titration.

13. Calculations for the various test sample volumes:

H2S Conc. PPM =

Where:

A = Borax solution used, ml

B = Oil Sample, ml

C = Aliquot volume, ml

D = Crude Oil density, gm/ml (e.g. 0.8200)

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ATTACHMENT 4(Section 5.2, 5.3 & 5.4)

GAS ANALYSIS METHODSROUTINE QUALITY CONTROL TEST GUIDELINES

Sample Frequency

Test ReferenceSales Gas Fuel Gas Injection Gas

H2S (ppm) Drager, Tutweiler (UOP-9/59, Attachment 5) or Orsat (Attachment 6)

W W W

CO2 (mol %) Drager or Orsat (Attachment 6) W W W

Dew point ASTM-1142, Shaw meter W W W

Gravity, calculated BELL Gt-922 W W W

Frequency: D - Daily Q - QuarterlyW - Weekly SA - Semi-annually (every 6 months)M - Monthly A - Annually or Non-routine

Note: Use API RP 44 as a gas sampling method reference.

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DETERMINATION OF HYDROGEN SULPHIDEIN GAS - TUTWEILER METHOD

Scope

This method is for the determination of hydrogen sulphide in gas mixtures. Mercaptan sulphur, if present, is determined as hydrogen sulphide. The accuracy of this method is not sufficient to obtain reliable results below 5 grains of H2S per 100 cu ft. (80 ppm).

This procedure is based on UOP Method 9-59.

Conversion of grains to ppm and Mol% H2S are as follows:

Mol % =

ppm H2S = 10,000 x mol % H2S

Outline of Method

The sample is admitted to a Tutweiler buret, displacing a starch solution. A known volume of starch solution is retained in the buret and a standard iodine solution is admitted and measured from the buret until the starch solution assumes a faint permanent blue colour. The concentration of hydrogen sulphide is calculated from the volume of iodine used and its know normality.

Apparatus

The apparatus shown in the drawing consists of a Tutweiler buret with a stopcock at the bottom connected by rubber tubing to a leveling bottle and a 2-way stopcock at the top. One branch of the stopcock is connected to a 10 ml glass-stoppered cylinder, graduated in 0.1 ml divisions, and the other outlet connected to the gas sample source. The Tutweiler buret has 2 graduations, one at the 100 ml mark and the other at the 110 ml mark. The volume from the lower stopcock to the 110 ml graduation is about 5 ml.

Figure 5-1: Tutweiler Buret

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10 ml Buret

100 ml

110 ml


ATTACHMENT 5 (Page 2 of 4)(Section 5.4)


Reagents

All reagents shall conform to the specifications established by the Committee on Analytical Reagents of The American Chemical Society, when such specifications are available, unless otherwise specified. Reference to water shall mean deionized or distilled water.

Starch solution. Mix 4 gm of soluble starch with 10 ml of water and 10 mg of mercuric iodine and rub into a thin paste. Pour into a litre of boiling distilled water, stir, allow to stand until cold, and pour off the clear solution for use.

Prepare fresh solution at 3 day intervals. When low concentrations are being determined by (0.001 N) iodine solution, renew the starch solution in the leveling bottle after a maximum of 3 analyses.

Standard iodine solutions. Three standard iodine solutions are usually sufficient for determination of the hydrogen sulphide content of most petroleum refinery gas streams. These solutions are made to specific normalities for analytical convenience.

IODINE SOLUTION A is for the determination of hydrogen sulphide when present in concentrations less than 1000 grains per 100 cu ft of gas. The specified normality is (0.01345 N), so that 1 ml of solution is equivalent to 100 grains per 100 cu ft of gas. To prepare this solution, weigh 1.7076 gm of purified iodine crystals into a 1 litre volumetric flask containing approximately 15 gm of potassium iodide. Dissolve in water and dilute to volume.

IODINE SOLUTION B is for the determination of hydrogen sulphide when present in concentrations greater than 1000 grains per 100 cu ft of gas. The specified normality is (0.0269 N), so that 1 ml of solution is equivalent to 200 grains of hydrogen sulphide per 100 cu ft gas. To prepare this solution, weigh 3.4152 gm of purified iodine crystals into a 1 litre volumetric flask containing approximately 15 gm of potassium iodide. Dissolve in water and dilute to volume.

IODINE SOLUTION C is for the determination of hydrogen sulphide when present in concentrations less than 25 grains per 100 cu ft of gas. The specified normality is (0.010 N), so that 1 ml of solution is equivalent to 7.4 grains of hydrogen sulphide per 100 cu ft of gas. To prepare this solution, weigh 0.1264 gm of purified iodine crystals into a 1 litre volumetric flask containing approximately 15 gm of potassium iodide. Dissolve in water and dilute to volume.

A convenient alternate method of preparing the solutions described above uses the commercially available deci-normal iodine equivalents supplied in sealed ampules. A solution of lesser normality is prepared by proper dilution of the (0.1 N) solution. Solution A is prepared by diluting exactly 134.53 ml of (0.1 N) solution to 1 litre in a volumetric flask. Solution B is prepared by diluting exactly 269.06 ml of (0.1 N) solution to 1 litre in a volumetric flask. Solution C is prepared by diluting exactly 10 ml of (0.1 N) solution to 1 litre in a volumetric flask.

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Procedure

Fill the leveling bottle with starch solution and connect to the bottom of the buret. Turn the stopcock at the top of the buret to connect with the gas inlet tube and raise the leveling bottle until the buret and inlet tube are filled with starch solution. Close the stopcock at the bottom of the buret. Flush the line from the gas source and attach it to the Tutweiler buret inlet tube with Tygon or neoprene tubing (see precautions). Open the stopcock at the bottom of the buret and lower the leveling bottle, drawing in gas until the level of the starch solution just passes the 100 ml mark on the buret. Close the stopcocks and disconnect the gas sample tube. Open the bottom stopcock and raise the starch solution to the 100 ml mark by raising the leveling bottle. Close the stopcock. With the gas slightly compressed, open the top stop cock to the air for a moment to bring the gas to atmospheric pressure. Open the bottom stopcock and lower the starch solution level to the 110 ml mark to place the gas under reduced pressure. Close the bottom stopcock and disconnect the leveling bottle from the buret.

Fill the graduated cylinder at the top of the buret with the standard iodine solution and record the reading. Turn the top stopcock to admit small amounts of iodine solution into the buret and shake well after each addition. Continue the addition until the starch solution assumes a faint, but permanent, blue colour. Record the reading on the graduated cylinder and subtract from the initial reading to find the amount of iodine used during the analysis.

A blank analysis should be run daily for each iodine solution used to determine the amount required to give the starch solution a faint, but permanent, blue colour in the absence of hydrogen sulphide. This blank determination is accomplished in the same manner as described above, except that a hydrogen sulphide-free gas or air is used. The volume of iodine solution required to establish the proper end-point for any specified starch solution is subtracted from the volume of iodine solution consumed in a quantitative determination.

Calculations

Multiply the millilitres (ml) of iodine solution consumed in titrating the sample by its equivalent in grains of hydrogen sulphide per 100 cu fit of gas. Depending on which iodine solution was used, the calculations are:

Iodine Solution A:

(ml A - ml Blank) x 100 = grains H2S per 100 cu ft.

Iodine Solution B:

(ml B - ml Blank) x 200 = grains H2S per 100 cu ft.

Iodine Solution C:

(ml C - ml Blank) x 7.4 = grains H2S per 100 cu ft.

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Precautions

It is recommended that gases to be analysed for hydrogen sulphide content be sampled driectly from the plant stream into the buret. If the sample is to be transported, it should be done in a glass or stainless steel container.

Do not confuse the blue colour of the iodine-starch complex with the opalescent milky appearance resulting from the separation of free sulfur.

When extreme accuracy is required, apply a correction factor to temperature and pressure to bring the gas to 60oF and 760 mm of mercury.

If the gas contains tarry vapours, pass it through cotton before admitting to the buret.

Precision

Duplicate results by the same operator should be considered suspect if they differ by more than the following amounts, depending on the iodine solution used:

Iodine Solution A: 10 grains

Iodine Solution B: 20 grains

Iodine Solution C: 5 grains

Refereces

1. American Gas Chemical Handbook, 3rd Ed. 4662, Chemical Publishing Co., New York (1929)

2. Tutweiler, C.C. J. American Chemical Society, 23, 173 (1901)

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DETERMINATION OF H2S AND CO2 CONTENT OF GASORSAT METHOD

Summary

100 ml of gas is taken at atmospheric pressure. The gas is contacted with a reagent to remove H2S and then another reagent to remove CO2. The loss of H2S and CO2 in ml is recorded as the H2S and CO2 percent respectively in the original sample.

Obtaining the Sample

The sample may be taken in a glass sample bottle by displacing acidified brine with gas or taken directly from the gas line through a fine choke.

Procedure - Refer to Figure 6-1

1. Turn the 3-way stop-cock, S, to open the apparatus to the atmosphere. Raise the Levelling bulb, L, to fill the burette to near the top. Turn S to close apparatus to the atmosphere.

2. Open S1 and slowly lower L, lowering the liquid level in the burette, B, and raising the liquid level in P1 up to the mark on the stem. Close S1.

3. Repeat Step 2 for P2 and P3.

4. With S1, S2 and S3 closed, turn S to open apparatus to the atmosphere. Raise the liquid level to the 100 ml mark at the top of the burette. Close S, opening the U-tube to the atmosphere.

5. Purge the U-tube with sample gas to ensure that all air is removed.

6. Turn S to pass the sample into the burette until the level is below the zero mark. Disconnect the hose to the sample point. Raise the level in the burette and equalise with the level in L at the zero mark. Close S. The apparatus now contains 100 ml sample gas at atmospheric pressure.

7. Open S3 to pass the gas in and out of P3, by raising and lowering the leveling bulb. Return the liquid level in P3 to the mark on the stem and equalise the levels in B and L. Read the level in the burette and take as the H2S percent absorbed from the gas. Repeat until results do not differ by more than 0.2 ml.

8. Pass the gas into P2 to absorb the remaining H2S. Repeat until a consistent figure is obtained and record this as the H2S percent (x) by volume in the gas sample.

9. Pass the gas into P, and repeat as above. Record the total loss (y) of gas.

10. % H2S = x (Step 8)

% total = y (Step 9)

% CO2 = y - x

Report results to the nearest 0.1 ml.

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Caution:

1. The solutions must be used in the order stated above: potassium hydroxide (KOH) will absorb H2S as well as CO2.

2. Solutions must be periodically replaced: a solution may be considered spent when excessively discoloured or when absorption time is long.

3. Care must be taken to ensure that the liquid levels in P1, P2 and P3, do not pass through S1, S2

and S3. The absorption solutions readily leave deposits that in the course of time will cause the stop-cocks to seize. Similarly the absorbent level should not be allowed to fall to the bottom of P1, P2 and P3; sample gas may bubble through and be lost to the atmosphere.

4. The stop-cocks should be frequently removed, washed, dried and then very lightly greased. The parts of the tubes into which they fit must be similarly treated. Do not use so much grease that the small-bore tubes become blocked.

Reagents

1. 30% Caustic Potash. Dissolve 300 gm of pure Analar Potassium Hydroxide (KOH) in 700 ml of distilled water in a Pyrex beaker and make up the KOH solution to 1000 mls with distilled water.

a) Add hydroxide slowly and stir until completely dissolved.

b) Do not shake in a stoppered flask or bottle to effect solution.

c) Safety: Avoid contact with eyes, skin or clothing. Wash eyes, skin or clothing thoroughly if contacted by the KOH solution.

d) Preserve the solution in a rubber stoppered bottle and allow any solid matter to settle before using.

2. 10% Cadmium Chloride. Dissolve 100 gm Neutral Analar Cadmium Chloride in 700 ml of distilled water and make up the solution to 1000 ml with distilled water. Acidify with a few drops of hydrochloric acid.

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Figure 6-1: ORSAT Apparatus

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S

S1 S2 S3

P1 P2 P3

B

U-tube filter packed with glass wool

Sample Inlet

3-way stop cock

Graduated measuring buretter

Water Jacket

Stopper

Stopper

L

Levelling bottle containing saturated acidified brine

S1, S2, S3 Stop Cocks

P1, P2, P3 Contact pipettes containing absorbents

P1 contains 30% KOH to absorb CO2

P2 & P3 contain 10% CdCl2 solution to absorb H2S

Drawing Key

PRODUCTION CHEMISTRY - CIMS-PC-1.0ATTACHMENT 7 (Page 1 of 3)(Section 5.2, 5.3 & 5.4)

WATER ANALYSIS METHODSROUTINE QUALITY CONTROL TEST GUIDELINES

Sample Frequency

Test ReferenceInjection Water Potable Water Wash Water Disposal Water

SG at 60/60oF API RP 45-2.31 SA A M M

pH API RP 45 2.1 (On-site) SA A M W

H2S (ppm) API-RP 45-3.10 SA A M M

CO2 (mg/l) API RP 45-3.5 SA A M M

O2 (ppb) Chemetric SA A W M

Resistivity/Conductivity API RP 45-2.91 - A - -

Na+ (mg/l) API RP 45-2.10 SA A M M

Ca+2 (mg/l) API RP 45-2.41 SA A M M

Mg+2 (mg/l) API RP45- 2.41 SA A M M

Cl- (mg/l) API RP 45-2.8 SA A M W

SO4 -2

(mg/l) API RP 45-2.71 or Hach SA A M M

HCO3- (mg/l) API-RP45-2.21 SA A M M

CO3-2 (mg/l) API RP 45-2.21 SA A M M

ATTACHMENT 7 (Page 2 of 3)

4/11/2023 - 20 - PROCHEM

PRODUCTION CHEMISTRY - CIMS-PC-1.0(Section 5.2, 5.3 & 5.4)

WATER ANALYSIS METHODSROUTINE QUALITY CONTROL TEST GUIDELINES

Sample Frequency

Test ReferenceInjection Water Potable Water Wash Water Disposal Water

OH- (mg/l)API RP 45-2.21

SA A M M

Fe, total (mg/l) ASTM D-1068 or Hach SA A M M

Oil in water (mg/l) API RP 45-3.17 or Attachment 8 SA A M W

Inhibitor, residual (ppm) ASTM D 2327 - - - -

Cl2 (ppm) Hach - D - -

TDS (mg/l) API RP 45-2.11 SA A M M

TSS (mg/l) NACE TM-01.73 (modified) (On-site) M - M M

Coliform (colonies/ml) Millipore - A - -

SRB (colonoies/ml) API RP 38 - - Q Q

Bacterial Contamination, total (colonies/ml)

Millipore - A Q Q

Frequency: D - Daily Q - QuarterlyW - Weekly SA - Semi-annually (every 6 months)M - Monthly A - Annually or Non-routine


4/11/2023 - 21 - PROCHEM

PRODUCTION CHEMISTRY - CIMS-PC-1.0(Section 5.2, 5.3 & 5.4)

Table 7-1: Non-routine Water Analysis Methods

Test Methods

Ba (mg/l) Hach or Outside Lab

Sr (Mg/l) Outside lab

4/11/2023 - 22 - PROCHEM


ATTACHMENT 8 (Section 5.4)

DETERMINATION OF OIL-IN-WATER BY INFRARED (IR) ABSORPTION

Apparatus

Wilks Miran 1AFF infra-red spectrophotometer

Sample Cuvettes (suitable for infra-red spectrophotometry)

Freon-113 (1,1,2-trichloro, 2,2-trifluro-ethane) or Arklone P

100ml sample bottle with scale

Whatman No. 4 9.0 cm filter paper

Hydrochloric acid (conc.) 100 ml

1.0 cc and 10 cc glass syringes

10 ml disposable pipettes and pipette bulb

Standard curve

Method

1) Instrument Preparation

Turn the instrument power switch to “ON” position and allow 30 minutes minimum warm-up (red pilot lamp indicates power on).

Instrument controls should be set as follows:

i) course zero = 1Xii) range selector = 1Aiii) meter response = 1

Fill curvette with clean Freon-113 and place in sample holder.

Adjust fine zero control so that meter response is equal to zero. Switch to 100% transmittance and adjust meter to 100% then switch back to original setting.

2) Sample Preparation and Determination

Obtain 100 ml of sample to be analysed in sample bottle. Cool to room temperature. (This is vital to reduce potential errors due to solvent evaporation.)

To measure total oil add 2 - 3 drops of concentrated hydrochloric acid with 1 cc syringe. Adjust pH should be less than or equal to 2.0. (This ensures that organic acids present dissolve in the solvent phase.)*

Add 100 ml Freon-113 or Arklone P.

Shake sealed sample bottle vigorously for 1 - 2 minutes. After first several shakes, vent the bottle to release pressure.

Allow the sample to separate for five minutes.

Use the pipette to remove approximately 5 ml of the settled Freon-113 or Arklone P extracts from the bottom of the bottle. Be careful not to extract any water along with the Freon-113.

Drip the Freon-113 from the pipette, through a piece of folded filter paper, into a sample cuvette. Try to minimise solvent evaporation losses.

Insert sample cell into instrument, read and record absorbency value.

Convert absorbency valued to ppm oil and grease (V/V) from the standard curve.

* To measure insoluble oil omit adjustment of pH.

4/11/2023 - 23 - PROCHEM


OILFIELD SCALE ANALYSIS FLOWCHART

4/11/2023 - 24 - PROCHEM

(3) Loss on ignition @

900oC

(3) Loss on ignition @

900oC

Sulfide, Iodometric

0.5 gm

Sulfide, Iodometric

0.5 gm

(5) CO2 Evolution0.3 gm

(5) CO2 Evolution0.3 gm

(6) Dissolve in HCl, evaporate, add HCl,

determine SO4 in filtrate

(6) Dissolve in HCl, evaporate, add HCl,

determine SO4 in filtrate

(7) Dissolve in HCl & HNO3, evaporate, add HCl, filter

(7) Dissolve in HCl & HNO3, evaporate, add HCl, filter

Acid-Insoluble matter ignite residue @ 800oC

-------------------------------------Add Na2CO3, boil, filter,

wash residue with HCl and ignite. Discard filtrate.

Acid-Insoluble matter ignite residue @ 800oC

-------------------------------------Add Na2CO3, boil, filter,

wash residue with HCl and ignite. Discard filtrate.

Neutralize with NH4OH, filter.Neutralize with NH4OH, filter.

(11) Ca & Mg(11) Ca & Mg (10) Free Sulfur precipitate with

BaCl

(10) Free Sulfur precipitate with

BaCl

(9) Fe, Al, Ignite @ 800oC.

(9) Fe, Al, Ignite @ 800oC.

0.4 gm0.4 gm 0.4 gm0.4 gm

0.5 gm0.5 gm

pptppt

filtratefiltrate

Filtrate (Ca, Mg & SO4)Filtrate (Ca, Mg & SO4) pptppt

(½ vol.)(½ vol.)(½ vol.)(½ vol.)

Field Sample

(1) Wash with water, decant, dry

at 105oC

(1) Wash with water, decant, dry

at 105oC

(2) Extract with CHCl3

(2) Extract with CHCl3



(Section 5.4)

OILFIELD SCALE ANALYSIS

1.0 Sample washing and preparation

1.1 Transfer the original sample to a 600 ml beaker.

1.2 Add about 400 - 500 ml warm distilled water and stir to mix.

1.3 Let the scale sample settle down then decant or filter.

1.4 Repeat steps 1.2 & 1.3 to remove water-soluble matter.

1.5 Check any chlorides remained with AgNO3.

1.6 Transfer the washed sample to a watch glass.

1.7 Dry for 1 hour at 105 °C.

1.8 Grind and mix the dried sample thoroughly, dry for ½ hour at 105 °C.

2.0 Chloroform Extractable (organic matter)

2.1 Assemble the extraction apparatus as illustrated either in method IP-53 or in Figure 9-1, attached.

2.2 Weigh the dried extraction thimble.

2.3 Weigh about 4-5 gm of a dried sample and add to the thimble weight.

2.4 Extract with chloroform or any suitable organic solvent.

2.5 Dry the thimble and its contents at 105 °C for ½ hour.

2.6 Cool and weigh the thimble.

2.7 Calculation :

2.7.1 % Extraction Loss (EL) =

2.7.2 Extraction Loss Factor (ELF) =

2.8 Transfer the Extracted sample to a mortar, Grind to pulverize and mix.

2.9 Dry for 1 hour at 105 °C and store in a desiccator. This is the analytical sample.

Note:

a. It is advisable to use the standard "Soxhlet Extraction Apparatus" (Figure 9-1). The advantages are:

(1) fresh solvent is continuously in contact with the sample (without having to introduce more solvent, which would dilute the extract) and

(2) the experiment takes place unattended and can conveniently occur overnight if desired.

b. A mixture of Chloroform & Xylene can be used to increase extraction efficiency.

c. All analysis can be applied directly on a dried sample if organics content is low. Thus, no need to use ELF for correcting results.

4/11/2023 - 25 - PROCHEM



(Section 5.4)


3.0 Loss on Ignition (LOI)

3.1 Weigh 0.4 gm of Extracted sample.

3.2 Heat to 900° C in a muffle for 1 hour.

3.3 Calculation :

3.3.1 % LOI =

3.3.2 % LOI (Reported) = % LOI (3.3.1) x ELF

Note: Ignition loss will include such constituents as organic matter, carbon dioxide from carbonate, carbon, water of hydration and sulfur (free, sulfide, sulfite).

3.4 % Water of Hydration = % LOI - [% CO2 + (% FeS x 0.4558)]

Note: If LOI carried out directly on dried sample, then % Extraction Loss (EL) from Step 2.7.1 should be subtracted from % LOI in the above formula in Step 3.4.

4.0 Sulfide Determination

4.1 Weigh 0.5 gm of Extracted sample in a tarred Iodine flask.

4.2 Add 25 ml I2 solution (0.1 N) into flask then 25 ml distilled. water.

4.3 Add 10 ml of 1:1 HCl, immediately stopper the flask, shake it and let stand about 10 minutes.

4.4 Titrate with (0.1 N) Sodium Thiosulfate solution, using Starch indicator to end point change (blue-colorless).

4.5 Calculation:

4.5.1 % H2S =

4.5.2 % FeS =

4.5.3 % Fe2O3 = % FeS x 0.9089 (To be subtracted from Fe2O3 in 9.6.2)

4.5.4 % FeS (Reported) = [%FeS + %FeS (10.6.3)]

5.0 Determination of Carbonate

5.0 Summary of Method

Carbon dioxide is liberated by acidification of the sample and the carbonate is determined from the resulting weight loss. This procedure is from ASTM D 2331-73 (1979), Standard Methods of Testing Water-Formed Deposits, Determination of Carbonate.

5.0 Interferences

Sulfur dioxide and hydrogen sulfide may be released from sulfites and sulfides respectively. They are the more common interference likely to be encountered in water-formed deposits. Preliminary testing of the sample (see Section 8) should indicate when such interferences may be present and to what extent.

4/11/2023 - 26 - PROCHEM



(Section 5.4)


5.3 Apparatus

5.3.1 Erlenmeyer Flasks - 50 ml capacity

5.3.2 Caps - Plastic and smaller than the mouth of the Erlenmeyer flask (for example of the polyethylene closures supplied for vials).

5.3.3 Balance - Preferably single-pan automatic capable of being read to 4 decimal places.

5.4 Reagents

5.4.1 Calcium Carbonate (CaCO3) powder.

5.4.2 Hydrochloric Acid (HCl, sp. Gr. 1.19) with 1 volume of water (1:1).

5.4.3 Wetting Agent - 100 Percent active non-ionic liquid wetting agent (e.g. Synperonic N.)

5.5 Procedure

5.5.1 Before applying this procedure to sample of water formed deposits gain proficiency by working with known quantities of calcium carbonate. All materials and apparatus must be essentially constant room temperature.

5.5.2 Add 20 ml of the HCl (1:1) to a 50 ml Erlenmeyer flask. Add 1 drop of wetting agent to the acid. Wipe the flask exterior carefully with a non-shedding tissue and weigh the flask (A) and contents to at least 3 decimal places.

5.5.3 Weigh out accurately 0.3 g of the extracted (Step 2.9) sample of water-formed deposit [use a larger sample when a very low carbon dioxide (CO2) content is expected] into a weighed plastic cap (B) that will drop easily through the mouth of the Erlenmeyer flask.

5.5.4 Add the sample cap all to the acid into the Erlenmeyer flask, stir contents by swirling when the reaction subsides.

5.5.5 When the reaction is complete (no further evolution of gas) again wipe the outside of the flask carefully with tissue.

5.5.6 Reweigh the flask and its contents (C).

5.6 Calculation:

5.6.1 Calculate the carbonate content of the sample as CO2 in percent as follows:

Carbonate as % CO2 =

If H2S is present, use:

% CO2 (Reported) = (% CO2 - % H2S) x ELF

where,A = Weight of Erlenmeyer flask with acid and wetting agentB = Weight of plastic cap with sampleC = Weight of flask and contents after CO2 evolutionS = Weight of sample% H2S = As determined Test No. 4 (Step 4.5.1)ELF = Refer to Test No 2 (Step 2.7.2)

4/11/2023 - 27 - PROCHEM



(Section 5.4)


6.0 Sulfate determination (SO4)

6.1 Use 0.4 gm of Extracted sample in a 250 ml beaker.

6.2 Add 50 ml distilled water and 50 ml of concentrated HCl.

6.3 Digest to decrease volume to 50 ml, filter and discard residue.

6.4 Add 30 ml distilled. water and 10 ml HCl (1:1) and heat to boiling.

6.5 Add 20 ml of 10% BaCl2 solution with stirring.

6.6. Cool and filter through filter No.42.

6.7. Wash the precipitate to remove any chlorides.

6.8. Ignite in a muffle to 800 °C.

6.9. Calculation:

6.9.1 % SO3 =

6.9.1 % SO3 (Reported) = % SO3 (6.9.1) + %SO3 (8.14.4)

7.0 Dissolution of analytical sample

7.1. Weigh 0.5 gm of Extracted sample into a 250 ml beaker.

7.2. Add 20 ml distilled. water and slowly add 50 ml of concentrated HCl.

7.3. Digest on a hot plate for 10 minutes, test the H2S evolution by lead acetate paper.

7.4. When lead paper indicates H2S-Free vapour, Add 5 ml of concentrated HNO3 and

digest to near dryness.

7.5. Add 50 ml HCl (1:1) and boil.

7.6. Filter through a hardened Ashless filter paper (No.542).

7.7. Wash the filter with hot distilled water. Save residue, filtrate and washing for the next analysis.

8.0 Acid-insoluble matter (SiO2 + Ba/Sr SO4)

8.1 Wash residue from step (7.7) to remove any chlorides.

8.2 Ignite the residue to 800 °C for ½ hour, cool and weigh.

8.3 Record weight as Wt.1.

8.4 Transfer quantitatively all residues from crucible into a 250 ml beaker.

8.5 Add 15g of Sodium Carbonate and mix.

8.6 Add 50 ml distilled water and boil to reduce volume to 10 ml.8.7 Add 25 ml saturated Na2CO3 solution and boil for 30 minutes.

8.8 Cool and filter through Whatman No.541.

8.9 Thoroughly, wash the filter with distilled water then hot HCl (1:1) to remove all Carbonates.

8.10 Wash the filter with distilled. water to get residue free of carbonates/chlorides.

8.11 Discard filtrate and washing.

4/11/2023 - 28 - PROCHEM



(Section 5.4)


8.12 Ignite residue to 800 °C for ½ hour, cool and weigh.

8.13 Record weight as Wt.2.

8.14 Calculation:

8.14.1 % Silica (SiO2) =

8.14.2 % Ba/Sr SO4 =

8.14.3 % Ba/Sr as SrO (Reported) = (8.14.2) x 0.5641

8.14.4 % SO3 = (8.14.2) x 0.4359

Note:

a. It has been determined that CyDTA* (acid form) at a 10:1 weight ratio in a basic solution of ammonium hydroxide would completely dissolve both strontium and barium sulfates (Reference 4). Therefore, the following alternative procedure would be preferable to apply in place of steps 8-4 to 8-10.

b. With availability of such instruments as Atomic Absorption Spectrophotometer (AAS) or Inductively Coupled Plasma (ICP), a complete dissolution and analysis can be carried out on a wide range of scale samples according to Reference 4.

8.4a Transfer quantitatively all residues, with water, from crucible into a 250 ml Erlenmeyer flask.

8.5a Add 3 gm of CyDTA and adjust pH to 10.8 with conc. NH4OH. (check with pH meter)

8.6a Dilute to about 200 ml, cover with Parofilm and stir overnight with a large Teflon stirring bar.

8.7a Transfer the sample with any residue remained to 400 ml beaker, remove ammonia with heat.

8.8a Cool, adjust pH to 8.0 with HCl, filter and proceed steps from 8.11 to 8.14.

*Cyclohexanediaminetetraacetic acid, HACH Cat. No. 7007.

9.0 Iron determination

9.1 Boil the filtrate and washing from step (7.7) to 100 ml.

9.2 Neutralize with NH4OH to precipitate Iron and Aluminium.

9.3 Cool and filter through Whatman No.541.

9.4 Wash the ppt. with hot 1% ammonium chloride solution. Save filtrate and washing.

9.5 Ignite the ppt. at 800°C for 1 hour.

9.6 Calculation:

9.6.1 % Fe2O3 =

4/11/2023 - 29 - PROCHEM



(Section 5.4)


9.6.2 % Fe2O3 (Reported) =

Note:

If Fe & Al required to be determined separately, dissolve ppt. in step (9.5) in HCl and apply analysis method specified for each metal.

10.0 Free Sulfur determination (SO4 + S)

10.1 Transfer the combined filtrate and washing, from step (9.4), to a 250 ml volumetric flask.

10.2 Dilute to volume and divide it into two portions. (each 125 ml).

10.3 Evaporate the first solution to volume 100 ml.

10.4 Adjust solution acidity to methyl orange end point, add 10 ml HCl (1:1).

10.5 Heat to boiling and follow steps from (6.5) to (6. 8).

10.6 Calculation:

10.6.1 % Total SO3 =

10.6.2 % Sulfur as S =

10.6.3 % FeS = % S x 2.742

10.6.4 %Fe2O3 = % FeS x 0.9089

11.0 Calcium and Magnesium Determination

Two methods are available for determination of Calcium and Magnesium:

"Method A - Gravimetric" when Ca and Mg exist in high concentrations.

"Method B - Complexometric titration" when Ca and Mg exist in low concentrations.

Method A - Gravimetric

11.A.1 Concentrate the Second Solution from step (10.2) to 100 ml.

11.A.2 Add 5 ml NH4OH (1:1).

11.A.3 While boiling add 20 ml saturated Ammonium oxalate solution slowly.

11.A.4 Heat the solution at boiling point for several minutes.

11.A.5 Cool and filter the ppt. through Whatman No.42. Save the filtrate.

11.A.6 Dissolve the ppt. with 5 ml conc. H2SO4.

11.A.7 Titrate with (0.1 N) KMnO4 solution to a pink color end point.

11.A.8 Calculation:

% CaO =

11.A.9 Acidify the filtrate from step (11.A.5) with HCl (1:1) when boiling.

4/11/2023 - 30 - PROCHEM

PRODUCTION CHEMISTRY - CIMS-PC-1.011.A.10 Add slowly 20 ml ammonium ortho phosphate 10% solution.

4/11/2023 - 31 - PROCHEM



(Section 5.4)


11.A.11 Evaporate slowly until a precipitate begins to crystallise.

11.A.12 Cool and make alkaline by adding NH4OH dropwise to the solution.

11.A.13 Allow the solution to stand over night.

11.A.14 Filter through No.42 and wash with diluted NH4OH.

11.A.15 Ignite the ppt. to 900 ° C for ½ hour. Cool and weigh.

11.A.16 Calculation:

% MgO =

Method B - Complexometric Titration

11.B.1 Pipette 5 ml of MgCl2 (0.02 N) solution into 100 ml beaker.

11.B.2 Dilute to 50 ml with distilled. water and add ammonia buffer.

11.B.3 Add Erichrome black T indicator.

11.B.4 Titrate with EDTA (0.02 N) solution to reach the blue color end point.

11.B.5 Record EDTA volume as " T 1 " Refill the burette with EDTA solution.

11.B.6 Pipette 50 ml of the Second Solution from step (10.2) into 100 ml beaker.

11.B.7 Add 5 ml of MgCl2 (0.02 N) solution and ammonia buffer.

11.B.8 Follow steps B.3 & B.4. Record volume as " T 2 " and Refill the burette.

11.B.9 Pipette another 50 ml of the same solution in step 11.B.6.

11.B.10 Add KOH solution and wait for 3-4 minutes.

11.B.11 Add Calcium indicator and titrate with EDTA to color change.

11.B.12 Record volume as " T 3 ".

11.B.13 Calculation:

% CaO =

% MgO =

Note:

Determine Zinc, when expected, in the solution from step (11) by HACH.

12.0 Reporting

Report all results as percentage by weight of dry sample in the CIMS Records Data Management System.

4/11/2023 - 32 - PROCHEM



(Section 5.4)


References:1. 1979 Book of ASTM Standards, Part 31.2. "Manual on Water". ASTM STP 442

3. Vogel., "Quantitative Inorganic Analysis", 4th Ed., Longman, 1981.4. Carel & Wimberley., "Dissolution analysis improves oil field scale treatment", OIL & GAS Journal,

Jan 14, 1991.5. Gershon J. Shugar & John A. Dean., "The Chemist's Ready Reference Handbook", McGraw-Hill,

Inc., 1990.6. Flopetrol, "Chemical methods to determine the composition of scale samples".7. C. W. Lapham., "Chemistry", GCE O-Level Passbook.

8. John Kenkel., "Analytical Chemistry for Technicians", 2nd Ed., Lewis, 1994.

Figure 9-1

Soxhlet Extraction Apparatus Drawing

4/11/2023 - 33 - PROCHEM


ATTACHMENT 10 (Page 1 of 3)(Section 5.2, 5.3 & 5.4)

EPA (USA) LABORATORY TEST METHODS FOR ENVIRONMENTAL SAMPLING

Substance Medium EPA Test Method

Alkalinity Drinking water EPA Method 310.1

Aluminum All EPA Method 6010

Antimony All EPA Method 6010

Arsenic Wastewater / surface water / saline water

EPA Method 206.2

Arsenic All EPA Method 6010

Asbestos content (Friable and non-friable)

EPA Bulk Method

Barium Water / soil / sludges / industrial waste EPA Method 6010

Base / Neutrals and Acids Wastewater EPA Method 625

Beryllium Water / soil / sludges / industrial waste EPA Method 6010

Biologic Oxygen Demand (BOD) Industrial & municipal wastewater EPA Method 405.1

Boron Water / soil / sludges / industrial waste EPA Method 6010

Bromide Drinking water EPA Method 320.1

Cadmium Water / soil / sludges / industrial waste EPA Method 6010

Calcium Water / soil / sludges / industrial waste EPA Method 6010

Chemical Oxygen Demand (COD) Wastewater EPA Method 410.1

Chemical Oxygen Demand (COD) Saline water EPA Method 410.3

Chloride (total) Drinking water EPA Method 300.0

Chlorinated Herbicides Soil / groundwater / sludges EPA Method 8150

Chlorinated Herbicides Waste water EPA Method 615

Chlorinated Hydrocarbons Soil / groundwater / sludges EPA Method 8120

Chlorinated Hydrocarbons Waste water EPA Method 612

Chromium Water / soil / sludges / industrial waste EPA Method 6010

Cobalt Water / soil / sludges / industrial waste EPA Method 6010

Conductance Drinking Water EPA Method 120.1

Copper Water / soil / sludges / industrial waste EPA Method 6010

Gasoline / Diesel - Light Ended Hydrocarbons

Soil EPA Method 8015(m)/8020 (BTEX)

Hardness Drinking water EPA Method 130.1

Hexavalent Chrome Wastewater EPA Method 7195

Iodide Drinking water EPA Method 345.1

4/11/2023 - 34 - PROCHEM





Iron Water / soil / sludges / industrial waste EPA Method 6010

Lead Wastewater / surface water / saline water

EPA Method 7420

Lead Water / soil / sludges / industrial waste EPA Method 6010

Magnesium Water / soil / sludges / industrial waste EPA Method 6010

Manganese Water / soil / sludges / industrial waste EPA Method 6010

Mercury Soils / Groundwater / Waste EPA Method 7470

Mercury Sediments / sludges EPA Method 7471

Molybdenum Water / soil / sludges / industrial waste EPA Method 6010

Nickel Water / soil / sludges / industrial waste EPA Method 6010

Nitrate (total) Drinking water EPA Method 300.0

Nitrogen - Ammonia Drinking water EPA Method 350.3

Nitrogen: Kjeldahl (total) Drinking water EPA Method 351.4

Nitrogen: Nitrate - Nitrite Drinking water EPA Method 353.3

PCB's, Pesticides, Herbicides Soil / groundwater / sludges EPA Method 8080

PCB's, Pesticides, Herbicides Wastewater EPA Method 608

pH Wastewater / saline water / surface water

EPA Method 150.1

pH Drinking water EPA Method 150.1

Phenols Soil / groundwater / sludges EPA Method 8040

Phenols Wastewater EPA Method 604

Phosphorus (total) Drinking water EPA Method 365.4

Polynuclear Aromatic Hydrocarbons (PAHs)

Soil / groundwater / sludges EPA Method 8100

Potassium Water / soil / sludges / industrial waste EPA Method 6010

Purgeable Aromatics Wastewater EPA Method 610

Purgeable Halocarbons Wastewater EPA Method 601

Purgeable Non-Halogenated Wastewater EPA Method 602

Purgeables Wastewater EPA Method 624

Selenium Water / soil / sludges / industrial waste EPA Method 6010

Silicon Water / soil / sludges / industrial waste EPA Method 6010

4/11/2023 - 35 - PROCHEM





Silver Water / soil / sludges / industrial waste EPA Method 6010

Sodium Water / soil / sludges / industrial waste EPA Method 6010

Solvents - Hydrocarbon Based Soil EPA Method 8010/8015/8020

Sulfate (total) Drinking water EPA Method 300.0

Thallium Water / soil / sludges / industrial waste EPA Method 6010

Total Dissolved Solids (TDS) Wastewater / saline water / surface water

EPA Method 160.1

Total Dissolved Solids (TDS) Drinking water EPA Method 160.1

Total Organic Carbon Drinking water EPA Method 415.1

Total Organic Carbon (TOC) Wastewater / saline water / surface water

EPA Method 415.1

Total Organic Halides (TOX) Drinking water EPA Method 450.1

Total Recoverable Petro. Hydrocarbons (TRPH)

Soil EPA Method 418.1

Total Solids (TS) Drinking water EPA Method 160.3

Total Suspended Solids (TSS) Wastewater / saline water / surface water

EPA Method 160.2

Total Suspended Solids (TSS) Drinking water EPA Method 160.2

Turbidity Saline water / surface water EPA Method 180.1

Turbidity Drinking water EPA Method 180.1

Vanadium Water / soil / sludges / industrial waste EPA Method 6010

Volatile Organic Compounds (Aromatics)


Volatile Organic Compounds (Halogenated)


Volatile Organic Compounds (Non-Halogenated)


Volatiles Soil / groundwater / sludges EPA Method 8240

Zinc Water / soil / sludges / industrial waste EPA Method 6010

4/11/2023 - 36 - PROCHEM



PRODUCTION CHEMISTRY DATA RECORDS

Reference Information:

Field

Location

Tag

Bank, RDS, FST, MOL, trunkline, etc.

Sample point location

Station, location or well

Equipment or string

Well flowing to (water injection/disposal)

Service

Position code

Remarks

Applicable procedures and standard nos.

Drawing nos.

Critical input data:

System Data

Sample date/time

System temperature

Choke bean size

System pressure

MMSCF/D

MBOPD

Water injected - BWPD

Water recycled - BWPD

Remarks

Oil Analyses

Routine

API gravity and density

Hydrogen sulphide (H2S) ppm by wt.

Basic sediment and water (BS&W) - % vol.

Water content - % vol.

Salt - lb/1000 bbl

Reid vapour pressure (RVP)

4/11/2023 - 37 - PROCHEM




Critical input data: Oil Analyses (Cont’d)

Non-Routine

Appearance

Relative density at 60/60F(SG)

Acidity (total) - mgKOH/gm

Ash - % wt.

Asphaltenes - % wt.

Sulphur - % wt.

Carbon residue - % wt.

Wax - % wt.

Sediment by extraction - % wt.

Viscosity (kinematics) cst at 70, 100 and 120 F

Fire point - F

Flash point (Abel) - F

Pour point - F

Nickel - ppm wt.

Vanadium - ppm wt.

Water Analyses

Routine

Bacterial contamination (colonies /ml)

SRB contamination (colonies/ml)

Coliform contamination (colonies/100ml)

Free chlorine (mg/l)

H2S in water (mg/l)

Specific gravity of water

pH of water

Oil in water (mg/l)

CO2 in water(mg/l)

Total suspended solids in water (mg/l)

Oxygen in water (ppb)

Resistivity/conductivity of water

Calcium (Ca) in water (mg/l)

Magnesium (Mg) in water (mg/l)

Iron (Fe) in water (mg/l)

Chloride (Cl) in water (mg/l)

Sulphate (SO4) in water (mg/l)

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Critical input data (Cont’d):

Water Analysis- Routine

Carbonate (CO3) in water (mg/l)

Bicarbonate (HCO3) in water (mg/l)

Hydroxide (OH) in water (mg/l)

Inhibitor residual in water (ppm)

TDS (mg/l)

Sodium (Na) (mg/l)

TSS (mg/l)

Millipore filter test data (filter pore size, pressure U/S and D/S, cc volume at 6 min., cc volume at 20 min., beta factor and original/final filter wt.)

Non-Routine

Barium (Ba) in water (mg/l)

Strontium (Sr) in water (mg/l)

Viscosity (cst) @ temp.

Gas Analyses

Routine

Hydrogen sulphide (ppm)

Carbon dioxide (mol %)

Calculated gas gravity (Air = 1.0)

Dew Point

Non-Routine

Nitrogen (mol %)

Methane (mol %)

Ethane(mol %)

Propane (mol %)

I - butane (mol %)

N-butane (mol %)

I-pentane (mol %)

N-pentane (mol %)

Hexanes (mol %)

Heptanes plus (mol %)

Gas BTU /ft3

Gas molecular wt.

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Critical input data (Cont’d):

Scale Analyses

Loss on ignition

Chloroform-extractable matter

Acid-insoluble matter as SiO2 (%)

Iron as Fe2O3 (%)

Calcium as CaO (%)

Magnesium as MgO (%)

Sulphide as FeS (%)

Sulphur, elementary as S (%)

Carbonate as CO2 (%)

Sulphate as SO3 (%)

Water of hydration as H2O (%)

Barium as BaO (%)

Strontium as SrO (%)

Sodium as Na (calculated) (%)

Chlorides as Cl (%)

Calculations:

% total water injection versus total fluid flow (oil and water)

% recycled water of the total water injected

Sum totals by field or facility

Total dissolved solids(mg/l)

Sodium (Na) in water (mg/l)

Typical output/report information:

Same as critical input data with sort options by date, sample type, service, location, current location, etc

Graphical outputs of results

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production chemistry cims pc 1.0

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