Mineral spirits are one of the most useful solvents in any shop, for thinning paint, cleaning brushes and spray guns, and degreasing parts. But once they’re dirty, you can’t just pour them out. Here’s how to dispose of mineral spirits safely and legally, how to reuse them, and when it makes sense to stop disposing of them altogether.
Never do this with used mineral spirits
- Don’t pour them down a drain. Not the sink, floor drain, toilet or storm drain.
- Don’t dump them on the ground. Solvent soaks into soil and groundwater.
- Don’t put liquid solvent in the trash. It’s a fire hazard in garbage trucks and landfills.
- Don’t burn them. Open burning of solvent is dangerous and illegal in most places.
Step 1: Reuse what you can
Most “dirty” mineral spirits are still good solvent with paint or grime suspended in them. Pour used mineral spirits into a sealed, labeled glass or metal container and let it sit for a few days. The solids settle to the bottom. Carefully pour off the clear solvent into a clean container and reuse it for cleanup. Only the sludge at the bottom needs disposal.
Step 2: Dispose of the rest properly
For homeowners and hobbyists
Take leftover mineral spirits and solvent sludge to a household hazardous waste (HHW) collection site or event. Most counties and cities run one. Keep the solvent in its original or a clearly labeled container with a tight lid, and don’t mix it with other chemicals.
For businesses
Spent mineral spirits from a shop is usually regulated as hazardous waste. Most mineral spirits have a flash point below 140°F, which makes the used solvent an ignitable waste (EPA code D001). That generally means:
- Storing it in closed, labeled, compatible containers
- Tracking how much you generate and staying within your generator category limits
- Shipping it with a licensed hazardous waste hauler on a manifest
Rules vary by state, so check with your state environmental agency and your waste hauler. Your solvent’s SDS lists its flash point.
Step 3: Handle solvent-soaked rags safely
Rags used with oil-based stains, varnishes or linseed oil along with mineral spirits can heat up and spontaneously combust. Lay them flat outdoors to dry completely, or store them in a sealed metal can filled with water until you can dispose of them according to local rules.
The better option for shops: recycle it on site
If your shop fills drums of dirty mineral spirits from parts washers, spray gun washers or paint cleanup, disposal turns into a steady expense: you pay to buy the solvent, then pay again to haul it away.
A solvent recycler breaks that cycle. It distills dirty mineral spirits on site, condenses clean solvent you can put right back to work, and leaves the paint, oil and grease behind as a small amount of residue in a disposable bag. Shops typically recover 97% or more of their solvent and cut both solvent purchases and hazardous waste volume by up to 90%. You can learn more in What Is a Solvent Recycling System and How Does It Work?
Recyclers are sized by how much dirty solvent you generate. Our free sizing guide and ROI calculator show what a recycler would save your shop. Need fresh solvent? We supply mineral spirits in 5-gallon pails, 55-gallon drums, totes and bulk. Mineral spirits is one of many recyclable solvents.
Make your mineral spirits last longer
The less often solvent gets dirty, the less you dispose of. In a solvent parts washer, a parts washer filter traps sludge so the solvent stays clean far longer. Using a dedicated parts washer solvent made for recirculating washers helps too. Not sure whether you need mineral spirits or something else? See Mineral Spirits vs. Paint Thinner.
Frequently asked questions
Can mineral spirits go down the drain?
No. Mineral spirits should never go down a sink, floor drain, toilet or storm drain. It can contaminate water, damage septic systems and create fire hazards in sewer lines.
Can you reuse mineral spirits?
Yes. Let used mineral spirits sit in a closed container until the solids settle, then pour off the clear solvent for reuse. Shops that use a lot of solvent can distill it back to like-new condition with a solvent recycler.
Is used mineral spirits a hazardous waste?
For businesses, usually yes. Most mineral spirits have a flash point below 140°F, which makes the spent solvent an ignitable hazardous waste (EPA code D001). Check your state rules and your SDS.
How do I dispose of rags soaked in mineral spirits?
Rags used with oil-based stains or finishes can spontaneously combust. Lay them flat outdoors to dry or store them in a sealed metal container filled with water, then dispose of them according to local rules.
Can mineral spirits be recycled?
Yes. Distillation separates clean mineral spirits from paint, oil and grease. On-site solvent recyclers recover 97% or more of the solvent and leave only a small amount of residue to dispose of.
Tired of paying to haul away solvent? Talk to us about sizing a solvent recycler for your shop.
