Crude stabilization and NGL (Natural Gas Liquids) recovery pumps handle hydrocarbon liquids, condensate, and light ends in oil and gas processing facilities. These pumps manage high vapor pressure fluids, corrosive sour service, and high-pressure separation processes. This guide covers stabilization/NGL pump selection, separation processes, fluid handling, and safety considerations.
Crude Stabilization and NGL Recovery Overview
| Component | Function | Typical Spec | Pump Type |
|---|---|---|---|
| Separation (3-phase) | Separate oil, gas, water | High pressure, 30โ100ยฐC | โ |
| Stabilizer feed pump | Pump crude to stabilizer column | High vapor pressure, 50โ500 mยณ/h, 10โ50 bar | API 610 OH2 (low NPSH) |
| Stabilizer column | Remove light ends (C1โC5) | 5โ20 bar, 100โ200ยฐC | โ |
| Reboiler pump | Circulate bottoms to reboiler | High temp, 100โ200ยฐC, high flow | API 610 OH2 (high temp) |
| Overhead pump | Pump overhead condensate (NGL) | High vapor pressure, low temp, 10โ100 mยณ/h | API 610 OH2 (low NPSH) or BB2 |
| NGL product pump | Pump NGL to storage/export | High vapor pressure, 50โ300 mยณ/h, 20โ80 bar | API 610 BB2 or multistage |
| Stabilized crude pump | Pump stabilized crude to storage/pipeline | 50โ500 mยณ/h, 20โ100 bar | API 610 BB2 or OH2 |
| Amine circulation (if sweetening) | Circulate MDEA/DEA | 50โ500 mยณ/h, 5โ20 bar | API 610 OH2 |
| Sour water pump | Pump sour water to stripper | H2S/NH3, corrosive, 10โ100 mยณ/h | 316SS or duplex |
Critical: High Vapor Pressure Hydrocarbon Pumps
| Fluid | Vapor Pressure | Pump Challenge | Solution |
|---|---|---|---|
| Crude (unstabilized) | 1โ10 bar (contains C1โC5) | Cavitation (NPSH) | Low NPSHr pump, flooded suction, booster |
| NGL (C3/C4 mix) | 5โ15 bar | Very high vapor pressure, flashing | Low NPSHr, pressurized suction, BB2/multistage |
| Propane (C3) | 8โ12 bar | Extremely high vapor pressure | Low NPSHr, vertical inline, flooded suction |
| Butane (C4) | 2โ5 bar | Moderate vapor pressure | Standard API 610, proper NPSH |
| Condensate | 0.5โ5 bar | Light ends, vapor pressure | API 610 OH2/BB2, NPSH margin |
| Stabilized crude | ๏ผ0.5 bar | Low vapor pressure (easy) | Standard API 610 |
Critical: Crude stabilization and NGL recovery involve high vapor pressure fluids (light ends C1โC5). Pump cavitation is the primary challenge. Solutions: (1) low NPSHr pump design (large eye, double suction, inducer), (2) flooded suction (tower/pump elevation), (3) booster pump on suction, (4) pressurized suction (tower pressure), (5) avoid excessive temperature (raises vapor pressure). Our API 610 OH2 and BB2 pumps have low NPSHr designs for hydrocarbon service.
Critical: Stabilization Process
- Goal: Remove light ends (C1โC5, methane through pentane) from crude to reduce vapor pressure for safe storage and transport. Stabilized crude typically has Reid Vapor Pressure (RVP) ๏ผ12 psi (0.8 bar).
- Process: (1) Crude from separator heated, (2) fed to stabilizer column (5โ20 bar), (3) reboiler at bottom (100โ200ยฐC) drives off light ends, (4) overhead vapor (C1โC5) condensed โ NGL product, (5) bottoms = stabilized crude (RVP ๏ผ12 psi).
- Pumps: (1) Feed pump โ high vapor pressure, low NPSHr, (2) reboiler pump โ high temp, high flow, (3) overhead pump โ high vapor pressure, low temp, (4) NGL product pump โ high pressure export, (5) stabilized crude pump โ standard pipeline boost. Our API 610 pumps cover all these services.
Critical: NGL Recovery Process
- Goal: Recover valuable NGL (ethane C2, propane C3, butane C4, natural gasoline C5+) from natural gas. Used for petrochemical feedstock, gasoline blending, LPG.
- Process: (1) Gas compression and cooling, (2) cryogenic expansion (turboexpander, -80 to -100ยฐC), (3) demethanizer (remove methane), (4) deethanizer (C2), (5) depropanizer (C3), (6) debutanizer (C4), (7) NGL products pumped to storage/export.
- Pumps: NGL product pumps (C2/C3/C4) handle very high vapor pressure (5โ15 bar). Low NPSHr critical. API 610 BB2 or vertical inline pumps. Cryogenic pumps for liquid methane/ethane (special materials, low temp). Our pumps handle NGL service.
Critical: Sour Service (H2S/CO2)
| Component | Corrosion Mechanism | Material | Pump |
|---|---|---|---|
| Sour crude (H2S) | Sulfide stress cracking (SSC), hydrogen blistering | Carbon steel (NACE MR0175), low hardness | API 610 with NACE-compliant materials |
| Acid gas (H2S/CO2) | Wet H2S/CO2 corrosion | Carbon steel (dry), alloy (wet) | API 610, proper seals |
| Amine (MDEA/DEA) | Alkaline corrosion, erosion | 316SS (high velocity), carbon steel (low) | API 610 OH2 (316SS trim) |
| Sour water (H2S/NH3) | Ammonia bisulfide corrosion | 316SS or duplex | 316SS or duplex |
Critical: Many crude stabilization/NGL facilities process sour crude (H2S). Pumps must use NACE MR0175-compliant materials (carbon steel with controlled hardness, or 316SS/duplex for wet sour service). Seals must handle H2S (toxic, flammable). API 682 dual seals with barrier fluid. Our API 610 pumps offer NACE-compliant configurations.
Critical: Common Problems
- Problem 1: Cavitation (high vapor pressure). Light ends/NGL high vapor pressure โ cavitation โ damage, poor performance. Solution: low NPSHr pump, flooded suction, booster, pressurized suction, temp control. Our pumps have low NPSHr.
- Problem 2: Seal failure (hydrocarbon/H2S leak). Seal fails โ hydrocarbon/H2S leak โ fire/toxic hazard. Solution: API 682 dual seal with barrier fluid (Plan 53/54), proper seal material, leak detection, gas detection. Our pumps use reliable API 682 seals.
- Problem 3: Reboiler pump high-temp failure. Reboiler bottoms 100โ200ยฐC โ seal/casing issues โ failure. Solution: high-temp pump design, proper cooling, API 682 high-temp seals, material selection (carbon steel or alloy). Our high-temp pumps handle reboiler service.
- Problem 4: NGL pump flashing. NGL (C3/C4) flashes at low pressure โ two-phase โ pump damage. Solution: pressurized suction, low NPSHr, proper piping, avoid pressure drop. Our NGL pumps prevent flashing.
- Problem 5: Sour service corrosion. H2S โ sulfide stress cracking โ catastrophic failure. Solution: NACE MR0175 materials, proper hardness control, corrosion inhibitor,ๅฎๆ inspection. Our pumps offer NACE-compliant options.
- Problem 6: Amine pump erosion/corrosion. MDEA/DEA at high velocity โ erosion/corrosion โ failure. Solution: 316SS trim, proper velocity (๏ผ3 m/s), filtration, amine reclaimer. Our amine pumps use 316SS trim.
Selection Summary
- Stabilizer feed (high VP crude): API 610 OH2 (low NPSHr, flooded suction, 50โ500 mยณ/h, 10โ50 bar)
- Reboiler circulation (high temp): API 610 OH2 (high-temp design, 100โ200ยฐC, API 682 high-temp seals)
- Overhead/NGL (very high VP): API 610 OH2 (low NPSHr) or BB2 (high pressure, 5โ15 bar VP)
- NGL export (high pressure): API 610 BB2 or multistage (20โ80 bar, high VP)
- Stabilized crude export: API 610 BB2 or OH2 (standard, 20โ100 bar)
- Amine circulation: API 610 OH2 (316SS trim, 50โ500 mยณ/h, 5โ20 bar)
- Sour water: 316SS or duplex (H2S/NH3 corrosion, 10โ100 mยณ/h)
- Critical: stabilization/NGL = HIGH VAPOR PRESSURE (light ends C1โC5, NGL C3/C4 โ low NPSHr pumps, flooded suction, pressurized suction, prevent cavitation/flashing) + HIGH TEMP (reboiler 100โ200ยฐC โ high-temp pump design) + SOUR SERVICE (H2S โ NACE MR0175 materials, API 682 dual seals) + AMINE (316SS trim, velocity control), all = product recovery + safety + environmental compliance
- Our API 610 OH2, BB2, 316SS pumps, and metering pumps cover stabilization/NGL facilities. For pump selection, talk to our oil & gas engineers with your fluid composition, vapor pressure, temperature, flow, and pressure requirements.