Compressed Air Condensate

There most certainly are regulations for discharging the toxic residue from compressed air systems!!

I'm not aware of the treatment needed, maybe oil water separation? But the condensate should be treated as a hazardous waste product.

John.

Yes you are right. There are regulations and there are numerous devices on the market to separate oil from water before it can bu put down the drain. This includes pouring it on the floor and letting run away to find it's own way to the drains/sewers etc.

The separator are common products and any compressor equipment supplier will have numerous models in their range to choose from.

I'll answer your question pertaining to the rules of the U.S.A.. The first thing that you must do is check with the entity who provides your sanitary sewer. All of the things allowed in sewage are regulated first by Federal Clean Water Act, then by additional State and finally Municipal rules. If the condensate discharges to a storm sewer-that is a big No No in the U.S.A..

The first thing is to use an effective oil/water separator. Be aware that a condensate separator is considered by some States and municipalities as a type of wastewater treatment and may require an operating permit.

Are you using petroleum or synthetic lubricants in the compressor(s)? For the type of separator chosen, the type of lubricant must be considered, along with compressor size, etc.. Unless technology has made tremendous advances in the past ten (10) years, then the synthetic oils are a bit harder to separate, and will be present in the treated discharge in a more significant amount than their petroleum counterparts. Under Federal guidelines the petroleum (or synthetic) part of the separated condensate is generally considered to be a nonhazardous, nonregulated waste, but certain States have laws that may change it to a regulated waste. In any case, the oily part of the separated discharge must be disposed of properly by an oil recycler or fuels blending operation.

Now, what does one do with the watereous part of the discharge? In most areas it can be sewered; especially with small compressed-air systems. With very large systems an evapourator can be used (but may require permitting) or the water may have to be collected and hauled away as a regulated or nonregulated waste.

I cannot furnish any true solution here, as I do not know the rules of the original poster's area concerning wastewater regulations. Basically, as the density of the human population increases, so does the severity of rules and the layers of those rules.

In the end, start with the provider of the sanitary sewer, and go from there.

Ing. Robert Forbus

Thanks to all for your answers. We are using a PAO oil, with coalesing filters. We are permited to dispose of our condensate in the sanitary. But as I was only told we could by a supervisor\safety coordinator I wanted to make sure if there was a reg. I have looked on the EPA site but it is so general I wasn't sure.

As I said, The Federal law enforced by the Federal EPA is the big one, but not the one that can cause much greif. The best place to start is the Municipal treatment entity. If they are okay with everything, then there's nothing to worry about.

In most places (at least the many places where I have been) the waterous part of the discharge is not a problem when placed in the sanitary sewer. Some States, and especially Municipalities, have a big issue with it because of the problems caused by contaminants from other contributors. Just keep it out of the storm sewer and you are usually fine.

Good Luck,

Ing. Robert Forbus

You learn something everyday.

I like the word 'waterous' - in 45 years in 'compressed air' I have never come across it.

I might use it myself!

Horace, I am not sure that it is a real word! I think it is, but it could have been one that I invented while I was learning the English language some thirty (30) years ago. Now that I mention it, I will look and see if it exists!

Ing. Robert Forbus

Horace, I tried to find the word "waterous". It does exist, but it is the name of a water pump company who builds pumps for fire pumpers and tankers, as well as fire pumphouses. That is probably where I got it, as in my youth I heard the term quite a bit and thought that it meant "something to do with water", and similar to the word "gaseous".

This is funny. Go ahead and use the word if you wish, as I can't take the full blame since I did not invent the word!

Best Regards,

Ing. Robert Forbus

Robert. Thanks for the background. Don't apologise. It's a word that conjours up a sense of watery wetness that everone should understand.

I will try it out and see what happens.

Condensate from compressed air is pure unless it is not contanimated. Please detail if it is contanimated and with what? Is it oil from the compressors then that needs to be rectified first. if otherwise than what?

Yes there is some PAO oil in the discharge. I am working on capture right now and seperation later. We are permited the small amount we discharge in the sanitary. I am not content with that and am looking into an oil/water seperator.