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Here’s how you can dispose of and turn your used cooking oil into soap, non-toxic pesticide, or biodiesel instead of pouring it down the kitchen drain.

Have you ever wondered what happens when you pour cooking oil down the sink? Let me tell you, it's not good!

That oil you thought was gone for good? 

It actually turns into a nasty, pipe-clogging mess. This can really mess up your kitchen plumbing and even cause big problems in your city's sewer system.

Take Clackamas County in Oregon, for example. I read that during the COVID-19 pandemic, with more folks cooking at home, their sewage pipes got jam-packed with grease and oil. It's a sticky situation, literally!

Now, I get it. Many of us are scratching our heads, thinking, "How in the world do I get rid of this oil?" Tossing it in the trash might seem like an easy fix, but is that really the best way?

Here's some good news: I've got some handy tips for you on how to safely say goodbye to that used cooking oil. Whether you're a beginner in the kitchen or a seasoned chef, these simple steps will make sure you're not part of the clog squad!

Dispose of Cooking Oil Without the Mess

Wondering how to get rid of that used cooking oil without causing a plumbing nightmare?

I've been there, and I've got some easy, eco-friendly tips for you:

Dispose of Cooking Oil Without the Mess

1. Let It Cool Down

Cooled cooking oil is much easier and safer to work with. If you prefer to deal with solid waste rather than liquid waste, put the grease in your freezer. This is especially the case with vegetable-based oils that remain liquid at room temperature. 

Trust me, it's way easier to handle once it's cooled. If it's something like bacon grease, give it a few hours to solidify.

But things like bacon grease will solidify once you let it cool down for a few hours. 

And remember, no hot oil in plastic containers — it's a melt-and-mess disaster waiting to happen. Glass jars are your friends here.

2. Solidify Before Oil Disposal 

Want to make disposal even simpler?

Mix the oil with something absorbent like old flour, sawdust, or cat litter. I've even thrown in some non-compostable food scraps to bulk it up.

3. Skip the Plastic

Plastic bags and bottles might seem convenient, but they can tear or crack, leaving you with a greasy mess. 

You’ll find that you have the same risk with plastic bottles that can potentially leak if they crack open. 

Been there, done that — wouldn't recommend it.

4. Eco-Friendly Storage Options

Ditch the plastic for something more earth-friendly. 

You really shouldn’t be dumping a plastic container in the waste, so the only other option you have is to use some form of biodegradable bags or containers. If you have a small cardboard container or even a compost bin liner, then those are better options. 

5. Household Waste Disposal

Once your oil is safely tucked away in a biodegradable container, just pop it in the bin. Some areas have special food waste bins, so it's worth checking with your local waste management.

6. Look For A Biofuel Center

Another way that you can dispose of it is by looking for local waste collection centers in your area that will accept cooking oil and turn it into biofuel. Such a grease disposal system is generally a good idea if you have a large volume of cooled oil on a regular basis. 

7. Clean Up The Cook Ware

After completing the safe cooking oil disposal, remember to wipe down your cookware with a rag before washing it with water.

Now, a little bit about paper towels: Some people's instinct is to use a sheet of paper towel to wipe away the oil since it's more convenient, but we actually don't recommend that.

This is because paper towels are no longer recyclable once they've been contaminated with food grease. The paper towel industry hasn't always been the greenest industry either. You can read all about it in our article on How to Stop Using Paper Towels.

Here’s a hint — you could opt for reusable paper towels!

By following these simple steps, you'll avoid plumbing problems and help the environment.

It's a win-win!

Where Can I Dispose Of Used Cooking Oil?

You can dispose of used cooking oil or grease properly at specialized sites. Please consult the Green Directory, a nationwide search engine for recycling centers.

Just go to "Green Directory" at the top of this page, enter “cooking oil” and your zip code to find the drop-off recycling locations closest to you.

The Green Directory can find recycling centers for many household items, including grease.

green directory

How to Repurpose Old Cooking Oil

Knowing how to dispose of cooking oil also means knowing how to use it for something else. Try these methods:

1. Reuse It in the Kitchen 

instead of disposing of cooking oil reuse it instead

Reusing cooking oil can be a game-changer. I've done this myself — you can safely reuse oil two or three times for frying.

Just make sure it still smells good.

Each reuse does lower its smoking point, so it's perfect for foods that don't require super high heat. It's a thrifty trick to stretch your oil a bit further.

2. Craft Homemade Soap

making soap from cooking oil fat

This one's a fun DIY project.

Soap traditionally comes from fat, and used cooking oil is an excellent substitute. I tried this once and was amazed by the results.

It's a satisfying way to recycle oil into something useful and kind to the environment — and your skin!

3. Help Turn It Into Biodiesel

biodiesel made out of cooking oil

Turning cooking oil into biodiesel isn't just for big restaurants. More and more people are catching onto this.

Biodiesel companies often welcome donations of used cooking oil. It's an incredible way to contribute to a greener planet. Imagine, the oil that once fried your potatoes could power a vehicle!

4. Create Non-Toxic Pest Control

Non-Toxic Pest Control with Cooking Oil

A lesser-known use I've discovered is using the oil as a base for non-toxic pest control solutions. Mixed with a few safe ingredients, it can keep garden pests at bay without harming the environment.

How NOT to Dispose of Cooking Oil and Grease

Ever wondered what NOT to do with used cooking oil and grease? It's super important to know the don'ts as well as the dos.

Let's dive in:

1. Don't Pour It Down the Sink

This one's a biggie. It might seem easy to just pour that liquid oil down the drain while running hot water, right? 

Wrong! 

I've learned the hard way that this oil quickly cools and solidifies, leading to nasty clogs in your pipes and, worse, in the city's sewers. Imagine a traffic jam, but with bacon fat and oil – not pretty!

2. Keep It Out of Your Compost

Now, you might think: "It's plant-based, so why not compost it?" 

Here's the catch — most cooking oils get mixed up with animal fats. And trust me, you don't want to attract rodents and maggots to your compost bin.

They're not just gross; they're a health hazard and can ruin your composting efforts.

3. Don't Mix It with Recycling

Some folks think putting oil in a plastic container or foil-lined bag and tossing it in the recycling bin is the way to go.

Nope. I once saw how a tiny leak can spoil an entire batch of recycling. Oil and grease can contaminate other recyclables, making the whole lot non-recyclable.

It's like one bad apple spoiling the bunch.

By steering clear of these common errors, you'll be doing your home plumbing, local sewer systems, and the environment a huge favor. Plus, you'll save yourself the headache (and cost) of dealing with clogged pipes!

Why Is Discarding Cooking Oil A Problem?

Discarding cooking oil is a problem because of several factors: 

Discarding Cooking Oil Infographic
  • Pouring grease or oil down the drain in your kitchen sink can clog or damage your home’s pipes once it solidifies. And putting hot water, degreasers, or detergents down your drain won’t necessarily help reduce the damage. The garbage disposal won’t help either.
  • Solidified grease can cause damage down the pipeline. It can also cause public tunnel systems to overflow, which can lead to health and environmental hazards.
  • Oil or grease leaks in your trash can attract pests and cause problems for garbage trucks. We won’t even go into how bad the smell can be. So when disposing of cooking oil, put it into a sealed, non-breakable container first before you toss it in the trash.

You can use these Compostable Trash Bags from Second Nature Bags specifically for that purpose.

These leak-proof, unscented bags are made using renewable, bio-based materials.

Some of these materials are sugarcane, plant-starches, and, coincidentally, vegetable oils so folks who have a sensitivity to plastics and toxins will have no problem using them.

These Second Nature Bags come in 13-gallon, 7-gallon, and 3-gallon sizes to accommodate different sizes of trash cans you may have in your home.

If you need something smaller, we can recommend getting these 100% Compostable Sandwich Bags

Pro Tip: To get the most out of them, use them several times to store fruits, vegetables, or snacks first, then use them one last time as a trash bag for your used cooking oil.

Tips for Reducing the Use of Household Cooking Oil

Here are four tips to reduce the amount of cooking oil and grease waste. 

Use Cooking Oil With A High Smoke Point

The most common oil for deep frying is corn oil, as it has a smoke point of 450 degrees. Some people have also switched to products like peanut oil which has the same smoke point. Coconut oil is also an option, but it has a lower smoke point of 350 degrees. 

While you won’t generally hit those temperatures while cooking, this is a good indication of how long it will last and how many times you can cook with it. 

Deep Fry Less Food

Everybody enjoys some deep-fried food, but we should probably all eat less of it. 

One option to still enjoy some of the good things in life is not to cook french fries in the deep fryer but in the oven instead. There are plenty of great products out there, and you’ll use a lot less oil. 

Invest In An Airfryer

Most things that you would commonly cook in a deep fryer will also taste great out of an air fryer. These still use a small amount of vegetable oil, but it’s nowhere near the amount you’d normally use. 

It’s also an awful lot healthier. 

Buy A Smaller Deep Fryer

If you don't regularly cook food for a large family or parties of friends, then consider buying the smallest deep fryer you can find. 

In a worst-case scenario, you can still prepare food for more people and simply keep it hot in the oven as you cook the food in several batches.

FAQ

How do you dispose of frying oil?

You can dispose of frying oil by taking it to a local recycling center that accepts used cooking oil. If you can’t do that, store it in a sealed non-breakable container first before tossing it in the trash.

Can you dispose of cooking oil in the garden?

Yes, you can dispose of cooking oil in the garden for compost, but it should have been used to fry plant-based foods. If it was used to fry meat, it may attract rats, raccoons, and other pests, so just bear that in mind.

Can you put cooking oil in the bin?

Yes, you can put cooking oil in the bin. But you should cool it down first and store it in a sealed non-breakable container (not a plastic bag!) so it won’t leak in the garbage.

How do I dispose of expired vegetable oil?

You can dispose of expired vegetable oil by tossing it in the trash in a sealed non-breakable container. You can also take it down to a local waste center that accepts grease. This is the most responsible method for disposing of cooking oil.

Can you pour vegetable oil down the drain?

No, you can’t pour vegetable oil down the drain — the grease will clog up the pipes or cause problems at the local wastewater mains for your area. Reuse it instead or store it in a sealed non-breakable container before you toss it in the trash.

What happens if you pour oil down the sink?

When you pour oil down the sink, the sink will get clogged up as the grease starts to solidify. This can cause your kitchen pipes or the local wastewater mains to overflow, which can be hazardous to our health and the environment.

Can you dump grease down the toilet?

No, you can’t dump grease down the toilet. If you do, it will clog up your pipeline when the grease solidifies.

When should you throw out frying oil?

You should throw out frying oil after you’ve reused it 2 or 3 times. However, if it smells okay and is still burning hot enough for you, then reusing it a couple of more times should be fine.

Conclusion

From reusing to making biofuel, there are so many inventive ways to get rid of cooking oil and old grease responsibly.

The important thing is to avoid dumping it down the drain, where it will end up blocking the flow and could even end up costing you dearly to call out a plumber. 

So, next time you’re about to pour cooking oil away in your kitchen, think again. There are many eco-friendly recycling centers and biodiesel companies that would love to put your cooking oil or kitchen grease to good use. 

You can find them all by using our Green Directory.

Chris is one of GreenCitizen’s writers who has been a long-time advocate of individual responsibility when it comes to the environment. He shares GreenCitizen's passion for making the world a better place every day of the year.

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