Importance of Bottle Test in the Petroleum Industry: Procedure and Best Practices

If you're in the petroleum industry, you may have heard of the Bottle test - a laboratory test used to determine the effectiveness of a demulsifier in separating water from crude oil. This test involves taking a representative sample of crude oil and adding a demulsifier to it in a specific dosage, before shaking it in a tightly sealed bottle to simulate the mixing that occurs during oil production.

Why is the Bottle test important? Emulsified oil can cause problems in oil production and refining, as water droplets dispersed throughout the oil can corrode equipment, reduce efficiency, and lower the quality of the final product. By identifying the best demulsifiers for a particular type of crude oil and production conditions, producers can improve their operations and reduce costs.

Not only can the Bottle test identify the most effective demulsifiers, but it can also determine the optimal dosage and application method for a given demulsifier. The test is a requirement for many producers to ensure compliance with industry standards and regulations and is an important tool for quality control and troubleshooting in the production and refinement of crude oil.

To see the Bottle test in action, check out the attached video! By investing in quality testing and analysis, producers can improve the efficiency and profitability of their operations while minimizing environmental impact. Therefore, it's important to ensure that the Bottle test is performed regularly and accurately by using proper sampling techniques and following standard operating procedures to ensure consistent and reliable results.

General Procedure of bottle test?

Safety Notice :

• Always refer to the product safety data sheet when available.
• Work in a good ventilation area?
• Avoid open flames or another source of ignition?
• Select appropriate gloves?
• Always work with safety in mind?

Sample:

• A crude oil bottle test is performed to analyze the quality oil
• A variety of emulsifiers are tested to see which chemical most effectively separates the emulsion into oil and water components
• Oil samples must be demulsifier-free.
• It's best to collect samples upstream of injection points
• The sample valve should be opened slowly will ensure a fresh, clean sample.
• Purging some oil from the sample point will ensure a fresh, clean sample
• If downstream collection is the only option, chemical flow needs to be turned off for a significant period.

Water Bath

• Prepare the water bath before proceeding to the bottle test
• The water bath should be full, and the temperature set to the same as the flow system
• For higher temperatures, another method can be used – such as an oil bath ''

How will you track your results?

• Use a bottle test sheet to track the number of bottles, chemicals, dosage rate, temperature, date, time, etc.
• The sheet should also be used to record water drops, interface quality, and thieving results (water, emulsion, solid).
• Any other observations of significance should be noted as well.
• This is one of the most vital steps in the process.

Bottle pouring best practices:

• Remove any free water (non-emulsified) from the collected sample.
• Make sure the sample is shaken thoroughly to homogenize its contents.
• Pour the sample into a squeeze bottle or pitcher.
• Immediately fill as many bottles as possible.
• Each bottle should be filled to the 100ml mark.
• If using a squeeze bottle, shake it after every 2-3 bottles are filled.
• Thoroughly shake the sample every time before refilling the squeeze bottle or pitcher.
• Assign a number to each bottle, always being sure to have one blank per sample test run

Dosage

• Begin dosing bottles with various demulsifiers and/or different amounts of the same demulsifier.
• You should keep a blank bottle chemical-free, acting as a good baseline/temperature indicator.
• Place all bottles into a water bath, with a thermometer in the blank sample.

Bottle shaking and Agitation

• ?Bottle shaking is important to Mix the chemical through the crude oil
• ?Shaking time need to match what is happening in the real system
• Calculations can be made for the length of time from the injection point to the treating vessel?
• Calculations can be also made for retention time for each vessel
• Shaking must be done consistently for each bottle

Reading the Water Drop:

• Water drop readings should be taken at timed intervals, based on the vessel's setting time or retention time.
• The first water drop reading typically occurs shortly after agitation.
• Subsequent readings are timed at longer intervals, such as every 10-20 minutes.
• Bottle tests should be read quickly without further agitation.
• Ensure that each bottle is handled in the same way during each reading.
• Note the amount of water in each bottle with every reading.
• Occasionally, also read the interface quality and water quality.
• Record any other significant observations.

Bottle reagitation:

• To simulate the actual production system, it may be necessary to re-agitate the bottles.
• For instance, if the oil is passed through a secondary device or pumped to another treating vessel.
• Re-agitate the bottles in the same way as the initial agitation, using the same number of twists or shakes.
• Note the time of re-agitation and any observations that may affect the results.

Thiefing & BS&W

• Fill a 12.5 ml centrifuge tube with Xytene.
• Thief 20 ml of fluid from the bottle with the highest water drop, taken from above the oil-water interface.
• Transfer the sample into the corresponding centrifuge tube.
• Rinse the thiefing pipette thoroughly between each sample.
• Shake each tube thoroughly (the bottle should be empty or contain only bubbles).
• Centrifuge each tube for 5 minutes.
• Use a flashlight (if needed) to identify the solid, water, and emulsion layers in each tube.
• Add 2-3 drops of F46.
• Reshake the tube.
• Centrifuge again for 5 minutes.
• Re-read and record the results on the bottle test sheet.

Composites

• Remove as much water from the bottle as possible – without removing any hydrocarbon
• Recap the bottle and shake to homogenize
• Pour each bottle into a centrifuge tube fill 50% with xylene
• Shake until there is nothing or a bubble
• Centrifuge 5 min
• There will be a significant amount of water – that doesn't matter – but needs to be recorded to differentiate the emulsion remaining
• Use a flashlight to read solid, water, emulsion
• Add 2-3 drops of Slugging compound
• Reshake
• Centrifuge again for 5 min
• Re-read and record on a bottle test sheet