Multi-phase flow measurement device for polymer flooded Oil field

Challenge Summary

A highly accurate measurement device to measure oil, water and gas rates of every well with very low tolerance limits for each phases to reduce calibration costs and reduce environmental impact.

Challenge Scenario

The oil fields deploy multi-phase flow meters to measure oil, water and gas rates for all the oil wells. Cairn has deployed such flow meters in Mangala, Bhagyam and Aishwarya fields. The flow meters use radioactive decay measurements to calculate the phase rates. As the polymer flooding process has started to extract oil, the field water cut increased and the injected polymer started breaking into the wells, the meters became progressively inaccurate and required frequent calibration. The measurement inaccuracy of these meters is a bottleneck to understand reservoir behaviour and production optimisation. Besides the usage of radioisotopes in the system is not very environmental friendly. Hence a measurement system with advanced technology to accurately measure multiple phases such as oil, gas and water is required.

Profile of the End-User

Oil and Gas Process supervisor

Functional Requirements of the End-User

  • Measure multiple phases of oil, gas and water flow rates with highest accuracy.

Functional & Operational Capabilities

  • Measure multiple phases of oil, gas and water flow rates with highest accuracy.
  • Auto calibrate according to variance in content due to injected polymer.

Operational constraints

  • Measuring phase fraction accurately is a difficult problem. The MBA field produce at high water oil ratio (typically > 10). Density contrast between oil and water is not very high. The water composition changes with time as injected polymer continues to break through. Gas fraction also changes with time.

Expected Tangible Benefits and Measurable Gains

  • Improvement in oil allocation factor close to 1.00.
  • Better reservoir management and production optimization opportunities- preventing
  • value leakage due to incorrect data.
  • Reduced operational spend on calibrations
  • Environment friendly method to measure flow.

Performance Metrics or Outcomes

  • Oil rate fraction within +/- 5%, water rate within +/- 5%, gas rate within +/- 10% of the physical measurement 
  • All the measurements will be tested against a "ground truth" measurement through a well test package and a surge tank over a period of 24 hours.
  • Reduction in opex of water management in mines