Within the wonderful world of oil and gas, it’s important for companies to be able to determine the volumes that are being produced from a reservoir. Governmental regulators have set out requirements for equipment, frequencies, and durations for each type of well testing to ensure proper volumes are being accurately measured and reported.
Well testing is typically performed by directing well production through a three-phase separator or, if hydrocarbon liquids are too small to be measured during typical well test durations, then a two-phase separator may be used.
Testing must be conducted as follows:
The test must begin only after a liquid level stabilization period.
- The test duration must be a minimum of 12 hours and typically conducted for 24 hours.
- After production begins at the proration battery, all wells must be tested within the first month, then again within six months, and then annually. New wells added to the battery must be tested within the first month of production, then again within six months, and thereafter annually.
- Consistent testing procedures must be used for consecutive tests to identify if a change in a well’s flow characteristics has occurred.
- These wells are usually tested by directing flow from the well through a test separator.
- The gas, condensate, and water volumes must be measured.
- The condensate must be sampled during every test and subjected to a compositional analysis, which is to be used to determine the gas equivalent factor (GEF). The sample may be taken from the condensate leg of a three-phase separator or the liquid leg of a two-phase separator (The water must be removed from the condensate before conducting the analysis).
- The GEF (Gas Equivalent Factor) must be used to convert the liquid condensate volume determined during the test to a GEV (Gas Equivalent Volume), which will be added to the measured test gas volume to determine the total test gas volume if the condensate is not delivered for sale at the group measurement point.
- The WGR (Water to Gas Ratio), CGR (condensate to Gas Ratio), and OGR (Oil to Gas Ratio) (if applicable) must be determined by dividing the test water, condensate, and oil volume respectively by the total test gas volume
- For orifice meters, the test gas meter must use 24-hour charts for a test period of 72 hours or less, unless electronic flow measurement is used; for testing periods longer than 72 hours, 7-day charts may be used, provided that good, readable pen traces are maintained
How ProMonitor Live helps with Well Testing
- Data Collection: ProMonitor Live communicates natively with all industry EFM manufacturers. This allows historical collection of production data. Every hour during a well test, ProMonitor collects logged minute day – 60 records of minute day for gas, condensate, and water production per hour.
- Mobile Device Use: ProMonitor Live gives field operators the ability to setup well test meters and the corresponding wells to be measured by each meter, ongoing production, and approval of the well test through a mobile application
- Setup of the Meter includes selection of the meter, its gas composition, meter configuration, and the duration of the test purging requirements either by time, by volume or a combination of the two. A regulatory purge formula is included if the operator wants to utilize the calculation for purging. Handy tool tips guide an operator though every step
- Reporting: Reporting of well testing production is automatically setup to report to volume production accounting. Once the operator has had a chance to review the test and compare the latest test to the previous five test results, the data is then store din ProMonitor Live and collected by the producer for reporting purposes. Once the approval is given by the operator, the final report is delivered to a company’s accounting within an hour. The system can also report the GEF, CGR and OGR and apply a water cut as required.
- There is no longer a need to schedule an operator’s time to swing the valves for a particular well test, then wait for the EFM device to pass the 12- or 24-hour contract rollover flow period and accumulate values for the 12- or 24-hour rollover needed by the EFM to report volumes. ProMonitor Live accumulates the minutes from the start of the test and for the duration of the test or until the operator declares the test finished. This means the time lapse from the end of one test to the start of the next depends solely on the operator swinging the appropriate valves for well selection and allowing an appropriate purge time.
- If an operator is not happy with the test results, there is an option for the operator to extend the test as required to achieve satisfactory test results. The operator does not need to start the test over form the beginning.
- Once the valves are swung to the appropriate well to be tested, all the above, including pushing the start button, is done through the mobile application.
- Operators have declared the system easy!