This paper highlights well test challenges, provides an overview of common problems, and describes the broader impact of inaccurate or infrequent well tests. This paper specifically focuses on production testing of wells in the Permian Basin, but many of these challenges apply to onshore oil and gas fields around the world. The Oil & Gas industry commonly utilizes a single well battery or multi-well test satellite for well effluent measurement. For the appropriate test facilities design, multiple design parameters such as fluid type, fluid rate, production capacity, reservoir capability, field development plan, development strategy, and capital budgets must be estimated. Due to lack of representative initial information on field, well flow, and reservoir characteristics, often coupled with communication issues between facilities, reservoir, production, and completions teams, this is a hit and miss target. Since the flow rates are dynamic in any field, the facilities are frequently under or overdesigned, significantly impacting profitability. Continuous, prolonged production tests are essential to overcome the multiple challenges mentioned above, but the appropriate testing could be cost prohibitive.

In summary, measurement challenges include:

• Infrequent tests due to:

∘ Measurement system cost

∘ Measurement system portability

• Measurement system accuracy

∘ Measurement errors may be due to measurement system sizing and changing flow rates from the well

• Lack of instantaneous liquid flow rate measurements due to liquid retention time in test separator

Impacts due to inaccurate and/or infrequent well tests:

• Uncertainty on individual well production – allocation estimates often have significant error

• Uncertainty on future production estimates

• Increased operating expenses due to:

∘ Non-optimal use of human resources – visiting wells that are producing as expected does not add value

∘ Non-optimal transition to artificial lift, non-optimal artificial lift system selection and configuration

• Reduced production near term and long term – it is not possible to improve what is not being measured

To overcome the measurement challenges in a cost-effective manner the industry has taken multiple approaches to create various inline test devices with limited success. This paper introduces a promising measurement system that is agile for transport and can be installed anywhere with a small footprint while delivering reasonably accurate results. The case study results outlined in this paper compare the third generation measurement system (with two-phase separator) measurements against a three-phase test separator that is permanently installed. Two unique wells were measured for this case study. A high condensate gas well with substantial water production was tested over a nine-month period. Then an unconventional well with gas lift, with low to medium water cut and medium API oil was tested for a five-month period. The measurement system was placed just upstream of the permanently installed three-phase test separator during this testing. In the future, facilities design engineers may utilize this promising technology breakthrough to create a paradigm shift in designing measurement systems that:

• Measure flow rates accurately

• Capture, analyze, and report data in real time

• Can be moved easily when needed

• Provide well intervention using smart phone or any internet connected device, by safety, operations, production, and reservoir personnel

• Provide high frequency measurements for EOR management and optimization

• Assist in identifying parent-child well interactions

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