If you are shopping for filtration separation, your first call is whether you are separating gas or separating oil. The two options in front of you represent exactly that fork: a used nitrogen membrane separator and a new cutting fluid skimmer. Both are for industrial or semi-industrial settings, but they are not interchangeable. The price spread is $203.84, with the nitrogen membrane at $1,500.00 and the oil-water separator at $1,703.84-about 12% apart. Since they do different jobs, the best choice depends on the workload you have, not on chasing a lower price.
Quick verdict
Go with the Nitrogen Membrane Separator if your operation needs on-site nitrogen. Go with the PreAsion Oil Water Separator if your shop needs to keep machine-tool cutting fluid clean. Neither is a one-size-fits-all filter, so the useful next step is to compare your existing setup with each unit's requirements.
Compared at a glance
| Product | Price | Condition | Focus | Price bar |
|---|---|---|---|---|
| Nitrogen Membrane Separator | USD 1,500.00 | Used | Nitrogen production for beverage/medical/industrial/processors | |
| 208-240V Machine Tools Industrial Oil Water Separator | USD 1,703.84 | New | Cutting fluid skimming for machine tools |
Where each product wins
The Nitrogen Membrane Separator wins for anyone producing nitrogen gas: it has the dimensions and pressure rating to support a high-demand draught beer system, and it carries a lower sticker price. The PreAsion Oil Water Separator wins for machine shops: it separates floating oil from cutting fluid, recovers oil through drainage, and includes a cleaning valve for tank-bottom sludge. That makes it a maintenance tool, not a gas generator. Look at what your facility already has: the membrane unit assumes an air compressor with tanks, and the skimmer assumes the right three-phase electrical supply. That alone can narrow the choice quickly.
Product notes
Green Air Nitrogen Membrane Separator
The Green Air Nitrogen Membrane Separator is a 45-inch-long, 6-8 inch wide unit that weighs about 30 lbs and is rated at 200 PSI. It was previously attached to a Green Air compressor with tanks, but that equipment is not part of this sale. The reason to choose it is straightforward: it was built to serve a high-demand draught beer nitrogen supply, and it enters at a lower price. The limitation is that it is used, and you will need to supply the compressor and tanks yourself. That means the total cost includes the air source you pair with it, not just the membrane price.
PreAsion® 208-240V Industrial Oil Water Separator
PreAsion® 208-240V Industrial Oil Water Separator is a new cutting fluid skimmer designed to separate floating oil from the fluid used in machine tools. Its oil drainage allows recovered oil to be reused, and its cleaning valve removes sludge from the tank bottom, which helps protect the working environment and employee health. The reason to choose it is its new, machine-tool-specific design: it targets the oily contamination that shortens cutting fluid life. The limitation is that it is built for 208-240V 3PH operations, so it only fits shops with that power setup, and it cannot produce nitrogen gas. If you need a skimmer, this is the one; if you need gas, it is not a substitute.
Final choice by use case
If your operation needs nitrogen gas, pick the Green Air Nitrogen Membrane Separator and budget for a compressor and tanks. If your machine shop needs a new cutting fluid skimmer, pick the PreAsion unit. In short: nitrogen gas points to Green Air; cutting fluid points to PreAsion.
