Nitrogen Generator for Aluminum Degassing

Most aluminum degassing operations run on industrial-grade nitrogen at 98% to 99.5% purity. Nitrogen acts as a carrier gas to pull dissolved hydrogen out of the melt, so high purity is generally not required for the sparging step itself. Higher purity (99.9% or above) is used when the same generator also feeds heat treating, laser cutting, or other downstream processes in the same plant. Our PSA and membrane systems cover the full 95% up to 99.9995% range and are sized to the highest-purity demand on the same nitrogen header.

Yes. Foundries running multi-shift degassing typically save up to 90% on nitrogen cost by switching from delivered gas to on-site generation. Cylinders run roughly $6 to $10 per CCF, dewars run $4 to $6 per CCF, and bulk liquid nitrogen runs $0.50 to $1.50 per CCF before boil-off losses. On-site generation lands at $0.05 to $0.15 per CCF depending on local power cost. Payback is typically 12 to 14 months.

Most rotary degassing units consume 100 to 1,500 SCFH per rotor depending on rotor size, melt volume, target hydrogen level, and treatment time. Lance and porous-plug sparging falls in a similar range but with different bubble dynamics. We rent a free wireless flow meter so you can measure actual consumption over a representative shift before sizing the generator. The data logger transmits readings in real time to our server with no WiFi required at your facility.

Pricing scales with flow, purity, pressure, and any custom requirements. Single-rotor foundries with one shift typically start near $15,000. Multi-rotor cast houses with continuous degassing usually run $40,000 to $150,000. Large facilities feeding degassing plus heat treating, laser cutting, or other downstream processes from the same generator reach $200,000 to $500,000. Payback is typically 12 to 14 months across system sizes.

Membrane is a strong fit when purity needed is 95% to 99.5% and flow is steady, because capital cost is lower and there are no sieve beds to maintain. PSA is the right choice when purity needed is 99.5% or higher, when other processes in the plant share the same nitrogen header, or when the customer wants room to grow into 99.9% or 99.99% later. We quote both technologies on most foundry projects and recommend the one that fits the rotor and the rest of the plant.

Sparging reduces dissolved hydrogen to acceptable casting levels, not to zero. Achievable hydrogen content depends on rotor type and speed, gas flow rate, treatment time, melt temperature, and atmospheric humidity. The treated aluminum should be cast quickly to avoid reabsorbing hydrogen from the foundry atmosphere during holding. We size generator flow and pressure to your target hydrogen level so the rotor can do its job.

Our systems are designed for 20 years or more of service. PSA systems use sealed sieve beds that do not require top-off or replacement under normal operating conditions. Competing systems with flanged sieve beds may require sieve replacement every 8 to 10 years, which is a significant hidden cost over the life of the equipment. Foundries are dusty environments, so we specify pre-filtration and locate the generator in clean compressed-air space when possible.

Start with the rotor or lance manufacturer SCFH spec, the number of stations running concurrently, and the duty cycle. If you also feed heat treating, laser cutting, or downstream processes from the same nitrogen header, list those flow rates and target purities. We provide free wireless flow meter rental to measure actual consumption over a representative period. Email your equipment specs and any measured flow data for a same-day quotation. Call 760-505-1300.