FOG Pretreatment

Long periods of inactivity hurt seals, fuel systems, and moving parts of most mechanical systems. That’s why many automobiles don’t like it.  Gas-powered lawn mowers and string trimmers don’t like it. Grease separators don’t like it either. 

The inactivity caused by pandemic shutdowns can make some grease interceptors more hazardous to your health. Let’s find out why by taking a closer look at what happens in separators with little or no input flows.

The discourse at CWEA's annual conference was lively despite the virtual setting. Pretreatment professionals discussed ways they adapted during the Pandemic, while cities shared aggressive plans to expedite permitting processes and get commercial clients up and running again. 

We speak to anyone with a FOG (fats, oils and grease) inquiry and often end up pointing them in a totally different direction than they originally were headed.  It’s a pattern in these conversations. Occasionally, this involves a caller with an MGD mindset. Here is an example of how one of these calls typically proceeds. 

Did you know the North American and European testing standards for certifying grease separators have nothing in common literally?

One is predominately a performance standard, a batch flow test simulating kitchen sink discharge. The other is mostly a design standard, a continuous flow test simulating floor drains receiving oily water flows. 

Both tests become more difficult to pass with higher flow rates. As a manufacturer, we respect the local codes and standards.  It is why we test our products to all applicable standards.

Hospitals and other health care facilities often operate extensive commercial kitchens. But unlike restaurants, hotels and other foodservice establishments, hospitals face additional cost-control, sanitation and operational challenges.

They have one or more commercial kitchens that may feed effluent into plumbing systems that run for hundreds or thousands of feet before exiting the building. 

Hospitals also operate on a 24/7 basis, requiring them to keep downtime to a minimum. They don’t close for holidays, and their kitchens must keep operating matter what.

These factors mean that hospitals face unique pretreatment challenges. Facility managers and engineers must carefully consider their pretreatment technology, or risk high-cost repairs and even breakdowns that could threaten the health of patients and workers.

I’m not fond of unsolved mysteries. When a service contractor stumped us with a problem in the late 1990s, the issue nagged at me.

The contractor told us about gelatinous masses building up in a handful of grease separators. The masses smelled terrible, he said, and the separators had surprisingly low water input flows.

We tried figuring out what the gel was. We ran tests in our lab. We looked online. We consulted wastewater treatment professionals and scientists. We couldn’t come up with anything.

Whenever I thought about the gel, I kept picturing the monster from the 1958 cinematic classic, The Blob.

Each state has its own unique environmental challenges and aims. You learn a lot by attending state conferences.

I recall a trip to the Florida Department of Health Conference in 1986 or 1987 when the buzz was about a growing set of research on extending lifespans of septic fields for rural food service establishments (restaurants, schools, other premises with commercial kitchens). This work remains vital to rural communities to this day.

Damann L. Anderson and his team at the University of Wisconsin in Madison were leaders in this area. In the ‘70s and ‘80s, they focused on the nutrient loading effect on septic field lifespans. Septic field failure occurs when a septic field no longer properly absorbs effluent. Instead, the water ponds at the surface, a public health hazard.

What is your plan when a city official, contractor, or engineer says a 1,000-gallon grease interceptor must be installed in your drive-through, parking lot, or another area where vehicles will be driving over it every day? 

Trying to comply with local codes and regulations shouldn’t be difficult. You shouldn’t have to use all your resources to engineer, install, and maintain a grease trap. It should be easier and more affordable. 

Commercial kitchen operators already know the benefits of using grease interceptors to capture used oil and grease -- cleaner sewage systems, reduced costs for wastewater treatment plants and fewer fines from municipalities.

Plus, you can protect your facility's interior plumbing and make a little extra money selling used cooking oil to recyclers.

But did you know that by capturing all that grease you're also helping cut greenhouse gas emissions?

When it comes to disposing of food waste, which works best for commercial kitchens and our waterways – garbage disposals or strainers?

At first glance, a garbage disposal might seem like the easiest choice – just flip a switch and the food is gone. No scraps to throw away. What could be simpler? Plus, you keep waste out of the landfill.

However, food scraps that enter the wastewater treatment system can cause problems with our municipal sewer systems.