Grease Traps vs. Grease Interceptors: A Comprehensive Comparison for Effective Waste Management

Waste disposal and management for food establishments is very important. It ensures that you have a clean working environment, and most importantly, that your business stays compliant. If you are going into the restaurant, hospital, school or other business where you have to cook for many people, you need to invest in the installation and grease trap pumping service.

When looking for information about grease trap installation and servicing, you will find the terms “grease trap” and “grease interceptor” being used interchangeably. However, these are two different devices that are used to capture grease, to prevent it from getting into the municipal sewer systems.

If you are going into the restaurant business, you are required by law to install a device to capture the grease. Therefore, it is to your best interest to know what between the grease trap and the grease interceptor will serve you best.

To help shed light on these two devices, you need to know their many differences. But first, what is so similar between the two such that they are used interchangeably?

Grease traps and grease interceptors work in the same way

These two devices work in the same way. When water from the kitchen sinks comes in, it contains water, fogs, oils, and grease.

The devices have inlets and outlets. Inside, they also have baffles, which slow down the flow of the water, to give the FOG time to separate from the water and float on top. The water is then filtered out, going to the sewer system, while the FOG remains in the tank. This is then scooped out, as soon as its level rises to about 25% of the trap.

Since the water from the kitchen contains food particles, the devices capture these two, which settle in the bottom while the FOG settles on top, where it solidifies.

Scooping is not enough to get rid of all the grease. Using a shop vacuum is also recommended to suck all the sludge out, and then the tank is cleaned thoroughly with hot water and dish soap to get rid of the nasty odor.

1. Grease Traps vs. Grease Interceptors: Size

Size is one of the most noticeable differences between the grease trap and grease interceptor. The FOG trap is smaller. Small ones, such as you would install for a small eatery, can be as big as the size of a breadbox (for about 10 gallons). However, some can be as big as a small fridge, but they will not exceed the capacity of 500 gallons.

Grease interceptors are large, most starting at a capacity of 500 gallons, and some can be as big as 2500 gallons. From this alone, you can be able to tell which would be used where. For instance, small establishments can use the grease traps while the big restaurants, and other establishments can use the grease interceptors.

You can see why knowing the difference between is important. For instance, if you install the grease trap for a large and busy kitchen, it will not be sufficient.

2. Flow rate and pressure

 The flow rate refers to the amount of water flowing into the grease interceptor or trap in a given time. Again, the bigger FOG interceptor comes with a higher flow rate, so it is perfect for busy kitchens. Typically, grease interceptors may have a flow rate of more than 50 gallons per minute. This means that every minute, there are more than 50 gallons of dirty water coming in from the kitchen sinks.

The FOG trap has a smaller capacity of less than 50 gallons per minute, which makes sense because if it were higher, it would fill up too fast.

Because of the low capacity and flow rate, it is possible to have a kitchen employee empty the trap when it is full. However, if it is a 500 gallon one, you can contract a grease trap service provider.

On the other hand, the bigger interceptor must be pumped, serviced and maintained by a grease trap company. That way, they will also handle the disposal of the grease.

There is also the matter of pressure, with the smaller FOG traps being the best for low pressure areas, which is why they can work well under the kitchen sinks. High pressure kitchens require grease interceptors as they can handle the high pressure pf water without breaking down.

3. Installation site

The smaller grease traps can be installed inside the kitchen under the counter, if the space allows.

They can also be installed under the kitchen floor, and the water from the sinks be directed to the trap. In most cases, though, the traps are installed under the kitchen sinks.

FOG interceptors are installed outside the kitchen, but adjacent to the area where the kitchen sinks are located. Mostly, the grease trap cleaning contractor will advise you on the best place to install the FOG tank. This can even be in the basement, or outside under the concrete.

While there are differences in the installation, it is important to have experts do the installation. The interceptor and the trap have sensitive parts, which must be installed in the right way. Thus, even if you get a small trap, have it installed by the technician. Remember, only gray water should go into the trap, and not black water.

4. Material, build quality, and durability

Since the grease interceptor is installed in high pressure work environments, it is made of high quality materials such as cement and fiberglass. It is also installed outdoors and underground, so it should be able to withstand the pressure from the elements.

The grease trap is for low pressure environments, so it is made of steel or plastic materials. Therefore, its durability is a bit short, as the steel can rust, and the acid build-up in the device can cause corrosion.

Usually, if the grease traps sustain damage, they have to be replaced in full, since they are not repairable in many instances.

However, the interceptor can be repaired easily if it develops cracks or other types of damage. The FOG interceptors have a longer lifespan of over 10 years. The smaller and more delicate FOG traps can last five or slightly more years.

The component that is most likely to fail in the grease interceptor is the gasket on the cover. It is made of rubber, so it is more vulnerable. You will know it needs changing when you start experiencing odors seeping from the interceptor.

5. Pumping and cleaning

The cleaning methods for the two devices are different, because of the differences in size. The FOG trap can be cleaned out easily, by one person. However, you would need double lined trash bags to keep the grease in, and then dump them in the trash bins to await garbage collection.

For the bigger interceptor, you will need to contract a provider of restaurant grease trap cleaning services. Because of the sheer size of this device and the complicated installation, it needs to be handled by technicians. Besides, it carries a lot of grease, which the company transports in a specialized tanker.

The grease trap pumping intervals also differ. Usually, the grease interceptor should be pumped and cleaned at least once every 90 days. However, if there is a surge in business, it should be emptied more frequently.

You should work with a company that can send a team to clean your FOG tank if you experience a high season in business.

Generally, the grease content in the interceptor should never be higher than 25 percent of the full tank capacity. Usually, this is about two or three inches of grease floating on the water in the chamber.

If the grease level exceeds this, it will start to back up into the kitchen plumbing, or it can start entering the sewer system.

6. Grease trap installation law

This differs from place to place, but there are some generic regulations that apply across the board. For instance:

• Every business that generates grease is required to install a grease interceptor or trap
• The grease interceptor should be installed at a good distance, to allow the hot grease to start cooling before it reaches the tank
• The size of the grease interceptor must be commensurate with the size of the business, and the grease output volume
• The business should employ other used cooking oil recycling methods to minimize what goes into the interceptor

Conclusion

There are so many things to consider when opening a new food business, and grease management is one of them. However, it is best to outsource such services, so that you can take care of the other aspects of your business.

You can contract a grease trap service company to ensure your grease management system is always operational. They will not only pump the grease and clean the system, but they will also do the required repairs in good time.

With an efficient team taking care of this vital aspect of your business, you can concentrate on making your customers happy, and getting the most productivity out of your employees.

A grease trap company will also ensure that your business is compliant with the local regulations. 

You may also like to read: Does Your Kitchen Have Odor Issues? Maybe It Needs Grease Trap Cleaning