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How to Dispose Used Cooking Oil?

Vegetable oil used for cooking

Reducing air pollution and global warming due to the large-scale shifts in weather patterns, is on everybody’s lips today.

Air pollution is mainly caused by the transportation sector on our planet, so the biodiesel industry in particular, is in desperate and immediate need for a greener, more cost-efficient and safer technology that can produce fuels from vegetable oils, waste oil, energy crops, etc.

By using biomass and waste products like used cooking oil to produce cleaner fuels, we can reduce the level of air pollution produced especially in major cities where a large number of vehicles are used daily.

Used cooking oil obtained from animal fast and a wide range of vegetable oils such as: sunflower, rapeseed, palm, soy, etc., is usually produced in restaurants and households, or in any other places where cooked food is produced.

If you produce used cooking oil at home or you own a restaurant where large quantities of used cooking oil are produced daily, you have to know how to properly dispose this waste product, to avoid any fines or any form of environmental pollution.

I advise you to avoid using overused cooking oil because can cause liver damage, depression and even cancer.

Throwing it in the sink or toilet is a bad solution because only one liter of oil can cause a blockage of the sewage system.

Can I Put Used Cooking Oil in My Garden?

If you have a garden, you can use cooking oil to successfully remove dirt, bugs, pollen, grime, and other gunk.

A composter can help you produce food for your vegetables. From time to time, you can add some used cooking oil to the pile to feed the worms that are working hard there to decompose the organic matter.

However, if you want to contribute to the reduction of air pollution in your area, you have to recycle the used cooking oil produced, because only this way we can reduce air pollution and the effects of climate change on the weather.

How to Properly Recycle Used Cooking Oil?

Luckily, there are several companies today that are specialized in collecting used cooking oil, which is later used to produce greener fuels and other useful products.

MBP Solutions is a company in Europe specialized in collecting and processing of used cooking oil.

If you live in Sweden, Norway and Denmark, you can use the used oil recycling service provided by the company.

What Happens with the Used Cooking Oil Collected?

Used cooking oil gets rancid and spoiled, but still contains a lot of energy that can be recycled to produce biodiesel, glycerol or bioparaffin.

After collection, the used cooking oil arrives at the production facility where is cleaned and heated to become liquid.

To separate the fats contained by the cooking oil, debris and waste products (water, protein and residues), are removed from the oil.

After cleaning, the purified oil will be used for biodiesel production, as an intermediate for distilling fatty acids and glycerol, or as technical grease for equipment.

How Is Biodiesel Produced From Used Cooking Oil?

Due to its performance and environmental qualities, biodiesel is a widely recognized blending agent for petroleum diesel.

Biodiesel is considered an alternative fuel for diesel engines produced from animal fats or used vegetable oil.

The advantages of biodiesel over petroleum-based diesel, are generated by the fact that biodiesel is not produced from fossil fuels like crude oil, but can be made from local crops.

Biodiesel can be produced from a variety of feedstocks, however, most of the time is produced from used cooking oil and animal fats produced locally.

The production of biodiesel starts with the removal of the impurities from the animal fats or used cooking oil.


At the same time, the viscosity of the oil is changed, so that is can burn in normal diesel engines without clogging the fuel lines. This is done through a chemical reaction called transesterification.

Transesterification is the biodiesel making process involving a chemical reaction of the used cooking oil (already filtered) with alcohol (methanol), using a catalyst (sodium methoxide) to speed the reaction.

A certain amount of alcohol and catalyst is combined with the feedstock (used oil), and the entire mixture is heated and agitated for a short period of time.

The mixture reaches a temperature between 55°C and 60°C (131°F to 140°F), and is vigorously agitated for about an hour, and then the mixture is let to sit for about two hours.

The result is a layer of biodiesel and a layer of glycerin. The glycerin is removed by draining it off the bottom, and then a wash process will remove the contaminants.

The co-product (glycerin) has a lot of other uses like making soap.

Making Sure That A High Quality Biodiesel Is Produced

To ensure that sound procedures are used to obtain a high quality biodiesel, the biodiesel production facility makes sure that they follow their quality control plan, which provides a detailed description of the entire process.

To produce quality biodiesel, you have to start by checking the feedstock.

The feedstock is filtered, pumped into a reactor, dried and tested for the presence of free fatty acids (FFA).

Excess water in the used oil will result in serious processing complications, so fats or oils with low free fatty acid content are preferred.

Waste oil (used cooking oil) can be high in free fatty acids, while other types of vegetable oil (canola oil), are much lower in free fatty acids, which makes them an ideal feedstock for biodiesel production.

However, because used cooking oil comes with a larger number of free fatty acids, more catalyst must be used in the chemical reaction, and more soap must be used to clean out the finished biodiesel.

The entire reaction process is performed twice, to be sure that the biodiesel produced is of high quality.

The two-step reaction strategy is used to ensure a complete reaction between the feedstock and the alcohol.

After draining the glycerin what remains is the biodiesel. However, it still has some excess methanol, catalyst and other impurities mixed in.

There are several wash methods available, but the water wash method is the most common, and is repeated until the fuel is clean.

The biodiesel is dried and an antioxidant is added. A series of tests are conducted on the finished product to certify that the clean fuel produced meets the ASTM biodiesel standards.

Once the biodiesel has been shown to meet the standards, a biocide is added to the fuel. The finished biodiesel, is a clean and high-quality fuel ready to use in any diesel engine.


Biodiesel produced from waste products (used cooking oil) can reduce the level of greenhouse gas emissions released by a diesel engine, and the production and sale of biodiesel, generates a domestic fuel economy.

Article written by:

I am a writer and reporter for the clean energy sector, I cover climate change issues, new clean technologies, sustainability and green cars. Danny Ovy

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