How to Identify Optimization Opportunities in Enalysis

Enalysis can help users identify compressors that may have unused capacity, unnecessary power consumption, or operating restrictions that are limiting production. The platform combines compressor specific models with actual operating data to calculate performance information that can be used to investigate optimization opportunities.

Optimization does not mean operating outside equipment limits. Any potential change should be reviewed together with the compressor configuration, manufacturer limits, current operating conditions, and the appropriate engineering resources before changes are made in the field.

What Enalysis information can help identify an optimization opportunity?

Enalysis calculates several values that can help show how effectively a compressor is using its available capacity and power:

• Power for compression used
• Total power used
• Driver power utilization
• Compressor capacity utilization
• Incremental production possible

Use these values together with pressures, temperatures, speed, compressor configuration, valve positions, and report trends to understand why an opportunity may be present.

Where should I start?

1. Confirm that the operating data in the report is accurate and represents the current compressor condition.
2. Review driver power utilization and compressor capacity utilization to see whether the unit appears fully loaded.
3. Review incremental production information and current compressor flow for potential unused throughput.
4. Look for pressure restrictions, bypass or recycle losses, or control positions that may be limiting the compressor.
5. Compare the current report with previous reports or loading information to determine whether the opportunity is persistent or related to a temporary operating condition.
6. Review the opportunity with your Detechtion Engineering Account Manager before making a compressor configuration or control change.

How can power utilization identify an opportunity?

Driver power utilization helps show how much of the available driver power is being used. A compressor that is not using its available power may have room for additional loading, depending on its capacity, mechanical limits, control settings, and field conditions.

For reciprocating compressors, the Enalysis optimization training uses performance loading curves to show the relationship between suction pressure, capacity, and power. On an optimized loading curve, the power section represents full power utilization, while the cylinder capacity section represents full cylinder capacity utilization. The knee of the curve is the point where both are at 100 percent.

How can capacity utilization identify an opportunity?

Compressor capacity utilization helps indicate whether the compressor is using its available physical capacity. If capacity utilization is below the available limit, review the reason before assuming more production can be added.

Possible causes can include compressor speed, unloading devices or clearance on reciprocating compressors, slide valve position on rotary screw compressors, bypass or recycle flow, suction restrictions, or other operating constraints.

Why should I review suction pressure and pressure restrictions?

The Enalysis optimization training notes that maintaining the lowest practical suction pressure can provide a production advantage in gas gathering applications. It also notes that compressor optimization should be reviewed regularly as field conditions change.

A pressure drop between the station inlet and compressor suction can indicate a restriction that may be limiting throughput. For rotary screw compressors, the training specifically identifies a large drop from station inlet pressure to compressor suction pressure as a potential capacity gain indicator.

What should I look for on a rotary screw compressor?

The Enalysis rotary screw training identifies several conditions that can point to unused capacity or avoidable power consumption:

• Compressor speed below the maximum appropriate operating speed
• Slide valve open more than required
• Bypass or recycle valve open
• A large pressure drop between station inlet pressure and compressor suction pressure
• Reported compressor flow below calculated compressor flow
• A Vi setting that does not closely match the operating conditions
• Unnecessary backpressure or over compression and under compression

The training describes a fully optimized maximum throughput condition as one where available capacity and or horsepower are fully utilized, the suction control valve is fully open, speed is set appropriately, the slide valve is fully loaded, the bypass valve is closed, and Vi is as close as possible to the optimum setting.

What should I look for on a reciprocating compressor?

For reciprocating compressors, optimization involves balancing available driver power, cylinder capacity, suction pressure, compressor speed, and cylinder configuration while staying within equipment limits.

Performance loading curves can help show whether the compressor is power limited, cylinder capacity limited, or operating near the optimized knee of the curve. Changes to clearance, speed, or other capacity controls can affect both throughput and mechanical loading and should be evaluated with the appropriate engineering resources.

Can Enalysis help identify power saving opportunities?

Yes. Optimization is not limited to increasing production. The training also describes using Enalysis to identify unnecessary power use.

For rotary screw compressors, examples include calculating an optimum Vi setting, reducing power wasted through over compression or under compression, and minimizing unnecessary backpressure. Enalysis can also compare calculated power use with driver loading to help identify discrepancies that may require further investigation.

Should I make a change as soon as Enalysis shows an opportunity?

No. An optimization opportunity is a prompt for further review, not an instruction to immediately change the compressor.

Before making a change, confirm the field data, review current equipment limits, consider related health and safety KPIs, and evaluate how the proposed change could affect pressures, temperatures, rod loads, reversals, power, capacity, and other operating limits.

Contact your Detechtion Engineering Account Manager for assistance evaluating the opportunity and determining an appropriate next step.

Why should optimization be reviewed regularly?

Field conditions change over time. Suction pressure, discharge pressure, available gas, equipment configuration, and compressor loading can all change the point at which a compressor operates most effectively.

Reviewing Enalysis reports and performance trends on a regular basis can help identify when a compressor that was previously optimized may now have unused capacity, unnecessary power consumption, or a new operating restriction.