How to Recycle UCO

How to recycle used cooking oil

Recycling cooking oil begins with cooling the oil in the fryer, draining the fryer and storing the used oil in a recycling bin. That recycling bin or tank can be inside the restaurant with pipes running from the fryer to the bin or it can be outside the restaurant with the oil transported to the bin in pots, or with a shortening shuttle or some other container. Once the cooking oil is deposited in the bin, the recycling can begin.

What does a used cooking oil recycler do?

Used cooking oil recyclers, such as Rebirth Biofuels, begin the recycling process by collecting the spent oil from the restaurant’s oil bin or tank. They arrive with a pumper truck, insert a hose into the used oil and deposit it in a tank on their truck. The oil is combined with that of many restaurants back at a large warehouse. 

The oil is heated for an extended period of time to remove moisture and cleaned to meet the specifications of biofuel producers who may use used cooking oil as a feedstock to make biodiesel, renewable diesel and SAF (sustainable aviation fuel). Each producer has their own specifications for the oil they will buy, but in general UCO needs to be: MIU (moisture, impurities and unsaponifiables) must be less than 2% and FFA (free fatty acids) less than 10%. This refined UCO is then sold to a biofuel producer for the next steps in making biofuel.

How does refined used cooking oil become biofuel?

Used cooking oil can be transformed into biodiesel, renewable diesel and SAF (sustainable aviation fuel) through a number of different processes.

How to make biodiesel fuel

Refined used cooking oil is converted to biodiesel through a chemical process called transesterification, a process that converts fats and oils into biodiesel and glycerin. Biodiesel can be labeled B5 (5% biodiesel) to B100 (100% biodiesel.) Biodiesel is typically blended with regular diesel. Biodiesel is rarely used in its purest form because of potential performance issues in engines not specifically modified for biodiesel. The most common blend of biodiesel fuel is B20.

What is renewable diesel?

Renewable diesel is distinctly different from biodiesel and is made by a different process. There are at least 6 different pathways for the manufacture of renewable diesel from hydrotreating to pyrolysis. Today, most commercial plants use hydrotreating, which involves reacting feedstock (such as refined used cooking oil) with hydrogen under high pressure and temperature.

Renewable diesel is described as a “drop-in fuel” in that it can be used in unmodified diesel engines without blending it with traditional diesel. Almost all renewable diesel is consumed in California because of California’s laws and their leadership with renewable fuels through the California Air Resources Board (CARB) and their LCFS (Low Carbon Fuel Standard.)

What is SAF (sustainable aviation fuel)?

SAF is made from several feedstocks including used cooking oil. It is usually blended up to 50% with conventional jet fuel. United Airlines has flown plans with 100% SAF already. Blended SAF can directly replace jet fuel and can reduce carbon emissions over the lifecycle of the fuel by up to 80% vs conventional jet fuel.

There are various processes for making SAF. One process for making SAF from refined used cooking oil is HEFA (Hydrotreated Esters and Fatty Acids). In this process, liquids undergo a chemical reaction with hydrogen and catalysts and are then distilled.

Emissions from aircraft make a significant contribution to climate change. The CO2 emissions from aviation are a significant contributor to climate change but also the NOx (nitrous oxides) and vapor trails. Emissions from aviation are growing faster than any other mode of transportation.

The environmental case for biofuels

The burning of biofuels results in lower carbon emissions(C02) and sulfur dioxide than the burning of conventional fuels. The use of biofuels to produce diesel fuel reduces America’s dependence on imported oil which contributes to our national security. Reduction of carbon emissions, particulate matter and sulfur dioxide slow the march of climate change. That is the conventional argument.

The case for biofuels gets a bit murkier when you consider the entire lifecycle or pathway of feedstock to biofuel. Much of today’s biofuel is derived from plants such as corn and soybeans. The climate value of biofuels produced from plants changes when you take into account the emissions associated with cropland cultivation and the energy utilized in producing biofuels. Growing crops (corn, soybeans, palm oil, sugar cane etc.) for feedstock for biofuels is highly controversial as many believe the land should be used for crops to feed people. 

The US Government is supportive of manufacturing biofuels from cellulosic material such as grasses, sawdust and paper; processes that the EPA reports having lower GHG (Greenhouse gas emissions). Unfortunately, today there is very little biofuel manufactured from cellulosic material in the U.S.

One of the very bright spots is that biofuel manufactured from lipids (eg. used cooking oil or yellow grease) has a very low carbon intensity pathway. This is because the pathway does not consider the carbon intensity of the original manufacture of cooking oil, only the carbon intensity of the process of converting waste cooking oil to biofuel. In other words the used cooking oil is a waste product and the original cooking oil was going to be manufactured and used anyway. And recycling the waste oil prevents it from being improperly disposed of and fouling public waterways and landfills.

States such as California through their LCFS (Low Carbon Fuel Standard) program reward fuels with low carbon intensities, such as biofuels, made from waste oil. The majority of credits created under the LCFS program are from lipid (used cooking oil) based feedstocks.

Biofuels are only one of the many possible and partial solutions to mitigating climate change. But the transportation sector is a huge contributor to climate change and biofuels are focused primarily on the transportation sector.

How to choose a grease recycling company

In choosing a grease recycling company you are choosing a business partner who will enhance the performance of your company. You want a company that is reliable, there when you need them and who leads the way in employing new technologies and services in support of your restaurant. Here’s what you should look for.

  1. Reputation and experience

Read their google reviews. Ask for 3 referrals from existing customers and call them. Ask the hard questions.

  1. Liability insurance

Accidents can happen. Make sure they have adequate insurance, at least $1MM per incident.

  1. Their recycling

Ask them what happens to the oil they collect. How do they recycle it? Where does it go? How can you confirm proper disposal?

      4. Accessibility

Ask for the phone number of the owner or the CEO. Call it. Can you reach him or her? Or  does it roll over to a phone bank? Can you get immediate help from a decision-maker?

      5. The Options

What alternatives do they offer for storing used cooking oil? Outdoor bins? Eco-tubs? Indoor tanks? Direct-connect? Wands? If they don’t offer these alternatives think twice. You want a supplier you can count on as you grow.

      6. Compensation

Do they offer rebates for the oil you provide? Is it based on the volume of oil or some mysterious number that only appears after the oil has been taken to a warehouse? How do they calculate rebates? Is it transparent?

       7. Grease trap cleaning

Do they also clean grease traps? You may want to call just one call supplier for cooking oil recycling AND grease trap maintenance. 

        8. Emergency spill requests

How do they handle emergency spills or an overflowing oil tank? Do they have 24/7 service for emergencies?

Once you’ve asked these questions and received answers then you can proceed to evaluating potential grease recyclers. Remember that the biggest is not always the best. You want a supplier who is responsive to your needs and a supplier to which you are an important customer, not just a number.

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Give us a call or fill out a form to learn more or get your used cooking oil service started as soon as you need it!

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