×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Truck/carwash water treatment and recycling

Truck/carwash water treatment and recycling

Truck/carwash water treatment and recycling

(OP)
Hello,

I'm looking for resources/books/info on how to treat and recycle water that has been used to wash vehicles (mostly plain dirt with some minerals). We are talking about a Grease trap plus maybe some Coalescing Filtration, so water can be reused for washing (not potable). Maybe also suitable for irrigating grass. I'm searching for info regarding volumes, steps needed, details, specs, tests, etc. just general info.

Thank you,
Regards.

RE: Truck/carwash water treatment and recycling

RE: Truck/carwash water treatment and recycling

I think in addition to grease trap, you need an oily water separator.

RE: Truck/carwash water treatment and recycling

(OP)
Thanks @IRstuff
@retired13 sorry for muy ignorance; what is the difference?

RE: Truck/carwash water treatment and recycling

Grease trap is an interceptor of solid waste, and the other you know it by name.

RE: Truck/carwash water treatment and recycling

Here is waste water pre-treatment requirements of a local authority, Link

RE: Truck/carwash water treatment and recycling

Is this a self service water spray or an automatic car wash?

What is the climate?

Do you have a discharge permit?

Why do you want to recycle?

Do you have someone that is capable of operating a recycle system? Operation of a recycle system may be problematic if there is no skilled personnel.

Do you use soap in this process?

What is raw water quality?

RE: Truck/carwash water treatment and recycling

(OP)
Hello Bimr,

This will be a self service water spray with a pressure washer.

Climate is desertic, its in the middle of a desert.

There is no sewage, treated water needs to be drained or reused.

Want to recycle because the climate and to not use too much water, so we don't feel bad.

Yes, I assume, I dont know the intricacies of the system yet (i'm exploring or searching for a solution we can buy).

Yes.

Potable drinkable water, possibly hard (haven't tested).

@retired13 Link is not working?

RE: Truck/carwash water treatment and recycling

Warning from self-service car wash operator blog:

"I had a reclaim system put in brand new in 1991 at my one self-serve washes. It was an eternal nightmare!! The first 6 months were great, after that it was all down hill. The water ended up smelling so bad I almost lost my entire business. Once I disconnected the reclaim, it took me 4 years to gain back 60% of my customer base. The cars would come out clean, but would smell like a sewage treatment plant. Then the cars ended up with actual road salt residue during the winter. The chemicals ate everything in the equipment room. All the copper is a brown green. Any exposed black pipe is rusted. Even the electronics in the equipment room started to fail. IMO, reclaim flat out does not work properly in a true self serve location. You absolutely have NO control over what is being washed down the drain. Your distributor is right, do not hook up the self serve bays, you will regret it.

On the other hand, the in-bay automatic's (IBA's) are a definite. Depending on your type of wash, you are looking at 60 to over 100 gallons of water for each car washed. The numbers add up quickly. The IBA's are in a controlled environment. Depending on you door setup, most people are not going to dump anything in the IBA, it would take too much effort. The SS bays are another story. Think about it, 5 quarts of oil, or motor home sewage down the drain. Paint, sheet rock debris, certain oils in the mud from mudders. Too many unknowns. You also can't control what function the customer would end with. For me it's a 60-40 split on rinse and HP wax. The only thing you could reclaim would be HP soap/water. Foam brush, tire cleaner, pre soak etc. do not use enough water to justify using reclaim in them. That only leaves HP soap/water. Customers only use it 35-40 % of all the cycles. You would only be reclaiming that much. 2 bay SS, not worth the hassle.

Even with today's technology I would be reluctant to put SS water into the reclaim. You can pretty much predict what you get in the reclaim from your IBA but in a SS you can expect more oil residue and other foreign matter that you have little or no control over. There is no way you should use reclaim in your SS as has already been stated."

Only 35-40% of the water in a self-serve is reclaimable. Evaporation and carry-out water are also higher on self-service systems. Self-serve car wash use much less water than in-bay automatic systems. The relatively low water usage of self-serve facilities resulted in suggestions for reducing the size of nozzles, with minor but measurable savings as a result.

Car Wash Org

Example of water reclaim system:

Reclaim system

You will probably need to find a local representative for sales/service.

RE: Truck/carwash water treatment and recycling

(OP)
No possibility of external service. Its in the middle of the desert. Operation need to be internalized.

No customers to scare away, its for cleaning trucks for a small earthworks/mining contractor. No neighbours around 1 km.

It appears reclaiming water is tricky as i'm starting to notice. At first I wanted to do a DIY solution with a grease trap, oil water separator, and maybe a filter (coalescer), so water can be drained to a french drain safely without risk of clogging, or be used to irrigate some plants we have there. Authority is not really concerned if untreated water is infiltrated to the soil, though one tries to do things the right way (still figuring out what is the right way exactly for this case). Odors if any could be managed by venting high (say with a vertical pipe 6 m high so odors are swept away by wind). But reusing the water to wash again seems it doesn't pay up if you buy a ready to use solution, considering it only reclaims 35% of it and ready to use systems appear costly, maybe they are marketed towards city carwashes, where its the core business and not an expense with little value added as this case.

I'm exploring the nuts and bolts of trying an ad-hoc DIY system that imitates those you mentioned, considering its components are not costly separately, and we do need to adapt it anyway to the way dump trucks are washed.

Thanks for all the info, if you have more please speak up, I'm still exploring.





RE: Truck/carwash water treatment and recycling

I think you can build a septic tank alike system. You'll need someone to calculate the process volume, and select suitable oily water separator though. You can use concrete, brick, or even the 500 gallon drums with piping in between.

RE: Truck/carwash water treatment and recycling

Now that you have explained this further, one would think a small basin should suffice. Use a section of the basin for oil collection. The oil/water section should underflow into a larger section of the basin to collect grit. Let the basin overflow to infiltrate into soil. Remove the oil and grit periodically.

RE: Truck/carwash water treatment and recycling

Many, many years ago I was helping with a project similar to this, a wash at an industrial site.
It was designed with separate stations for wash and rinse in one bay (vehicles pulled forward about 20').
The wash water was dumped, fresh water was used for rinse, and used rinse water made up about 50% of the wash water.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close