Top Bioremediation Solutions for Fat, Oil, and Grease in Wastewater: Lessons from a Real Hotel STP Case Study

Commercial kitchens are the most active and busiest areas. In a day, a hotel kitchen performs a series of activities such as washing utensils, cleaning frying stations, preparing dozens of meals, removing leftovers, and dealing with fat, oil and grease (FOG) which are constantly spilled. This is the usual activity in the foodservice sector, but it actually creates a hidden very serious problem in the hotel wastewater treatment system, a problem that most hotels are having a hard time dealing with.

We at Amalgam Biotech were most recently contacted to treat a sewage treatment plant (STP) at a luxury hotel where FOG had invaded nearly every stage of the process. The case turned out to be a stunning demonstration of bioremediation's power to eliminate such troublesome and persistent issues more effectively than chemical or mechanical methods could.

The post outlines the FOG science, distinguishes between fats and oils, discusses the field problems in the hotel business, and demonstrates the biological treatment's efficacy through our case study. It is straightforward, elaborative, and the understanding is based purely on actual practice.

Understanding Fats, Oils, and Grease (FOG): A Quick, Simple Guide

Before discussing STP challenges, it’s important to understand what fats and oils are in everyday terms.

1. Fats and oils definition

Fats and oils are natural, water-insoluble substances made of triglycerides. They come from plants and animals and end up in wastewater during cooking and cleaning.

2. Difference between fats and oils

A simple way to understand their behavior:

Fats	Oils
Solid at room temperature	Liquid at room temperature
Mostly from animals	Mostly from plants
Form thick floating layers in tanks	Spread easily but still create greasy films

This basic classification of fats and oils matters because each type behaves differently in water, and both can overwhelm STP microorganisms.

3. Examples of fats and oils entering hotel drains

Common hotel kitchen FOG includes:

• Butter, ghee, cream, and meat fats

• Sunflower, palm, coconut, and cooking oils

• Marinade oils, gravies, salad dressing leftovers

• Residual oil from frying stations

  
  

These substances stick to pipelines, choke aeration, and cause sludge imbalance. Even the best kitchen grease remover cannot stop them from reaching the STP.

Why Conventional Approaches Are Not Enough

A lot of hotels depend on fast solutions:

1. Chemical grease remover

It is a temporary solution, but it does not digest the grease. The FOG is reduced to smaller pieces, which however float back and get collected again.

2. Liquid oil degreasers

These are excellent for cleaning and maintaining surfaces but ineffective in biological tanks.

3. Hot water under pressure

The water jets force the FOG deeper into the sewer system rather than discharge it.

4. Manual grease-trap cleaning

This is a must-do, but the method is not efficient for dissolved and emulsified oils.

All these methods are not capable of touching fat and grease at a biological level. That’s exactly where we come into play.

Case Study: How Amalgam Biotech Restored a Hotel STP Overloaded with FOG

A well-known hotel approached Amalgam Biotech with serious performance issues in their hotel wastewater treatment plant. Let’s break down what we found and how we solved it.

The Problem: When FOG Becomes a System-Wide Threat

In the course of our evaluation, we noticed a number of symptoms:

• A greasy layer floating in the equalization tank that was very thick and greasy

• Diffusers with an oil coating that reduced aeration

• Aeration tank with grease buildup that impacted the oxygen levels

• Anaerobic pockets' unpleasant smell

• Sludge not settling properly

• During the inlet collection, FOG lumps were seen

  
  

The hotel has previously used several grease remover chemicals, but the issue still came back.

Root Cause

Our analysis showed:

• The FOG load from the kitchen was extremely high. 

• Fats and oils were not broken down properly. 

• The conditions of shock-load were destroying the beneficial bacteria. 

• The grease trap was inefficient because of the maintenance habits. 

• There were not enough microbial species that could digest the FOG. 

  
  

In summary, the STP lacked the biological power it required.

The Amalgam Biotech Solution: Targeted Bioremediation

We deployed a custom bioremediation program using FOG-degrading microbes specifically designed for wastewater treatment for hotels.

Step 1: Introducing specialized microbial cultures

Our microorganisms have the capability to process and classify the entire range of fats and oils. This includes:

1. saturated and unsaturated fats

2. fats from animals

3. oils from plants

These microbes convert fats, oils, and greases into basic and harmless substances, something that no chemical oil grease remover can do.

Step 2: Continuous dosing for stabilization

A proper and consistent dosage schedule allowed the system to restore its ecological balance, which in turn facilitated the oxygen transfer and also stopped any new lessening of the oxygen.

Step 3: Improving aeration

Immediately, the DO level in the Aeration Tank increased on even distribution of O2 through the water as the floating layer of fats thinned down.

Step 4: Strengthening grease-trap performance

Our solution acted as a natural grease stain removal booster. Over time, grease trap blockages reduced significantly.

The Results: A Complete Transformation in the Hotel STP

Within weeks, the outcomes were clear and measurable.

1. Floating FOG layer has been cut down by more than 70%: aeration was enhanced and the scum layers virtually vanished.

   
   

2. Water clarity of treated water was greatly improved: final treated water indicated improved BOD and COD levels.

   
   

3. Odor complaints were diminished: less anaerobic activity resulted in fresher-smelling tanks.

   
   

4. Sludge stability was improved: more MLSS consistency was obtained with better settling properties.

   
   

5. The need for chemical cleaners was reduced: the kitchen staff experienced fewer clogs in the pipelines and a lower demand for strong cleaning agents.

   
   

6. Grease accumulation was prevented for a long time: as the microbes continuously digest the FOG, the recurrence has been significantly reduced.

   
   

This actual case demonstrates that the biological methods provide consistent and durable results, which is a quality that chemical cleaners cannot offer.

Why Bioremediation Works Better Than Chemical Methods

Biological treatment brings hotels a variety of advantages, which include: 

• Consumption of grease instead of just breaking it down

• Implementation at all levels of the STP

• Less scum formation so that the machines are protected

• Natural prevention of odors

• Decrease of shock-loading and betterment of plant resilience

• Simplification of the hotel's wastewater treatment system 

  
  

Bioremediation is not a solution but rather the smart and green way of dealing with problems related to fat, oil, and FOG.

Selecting the Right Solution for FOG Management

While selecting a wastewater treatment system for the removal of oil and grease, hotels should inquire:

• Are the oils & fats just dissolved or are they further digested by the product?

• Is there any evidence of field success in hotel establishments?

• Is it applicable to all types of fats and oils?

• Will it lead to less reliance on chemicals?

• Does the supplier provide technical assistance?

  
  

Amalgam Biotech answers “yes” to all of the above.

Sustainable wastewater treatment starts with proper FOG management in hotels, ensuring long-term system performance and environmental compliance.

Conclusion

FOG is among the chief unseen foes of hotel sewage treatment plants. It reduces the efficiency of the whole process, makes maintenance more expensive, and causes the equipment to wear out quicker. However, applying the right biological method, hotels can make a giant leap forward in their plants' performance.

Our research offers definite evidence:

FOG can be biologically managed, STP performance gets better quicker, plant stability gets to be a long-term condition, hotels cut expenses on chemicals and maintenance

If your hotel is struggling with fats and oils, grease buildup, scum layers, or unstable STP performance, Amalgam Biotech’s microbial formulations can restore control quickly and sustainably.

Frequently Asked Questions

What are fats and oils in hotel wastewater, and why do they cause problems?

Fats and oils are organic substances commonly released during cooking, frying, and dishwashing in hotel kitchens. These include butter, ghee, cream, meat fats, and various plant oils. Because they are water-insoluble and sticky, they float, form thick layers, and block aeration inside the STP. Over time, they overload the system and make hotel wastewater treatment inefficient.

What is the difference between fats and oils in the context of wastewater treatment?

The difference between fats and oils is simple: fats are solid at room temperature, while oils are liquid. In wastewater:

• Fats create floating scum layer

• Oils spread into thin films that interfere with oxygen transfer

  
  

  Both types contribute to FOG load and require proper fat and grease removal methods preferably biological digestion rather than chemical cleaning.

  
  

Can chemical grease removers solve FOG problems in hotel STPs?

Chemical grease remover products can temporarily dissolve or break apart grease, but they do not digest it. As a result, the grease reappears within days. This is why many hotels experience recurring issues even after using kitchen grease remover liquids. Bioremediation works better because microbes actually consume and eliminate the grease.

How does bioremediation help in oil and grease removal from wastewater?

Bioremediation introduces specialized microbes that digest the full classification of fats and oils including saturated fats, unsaturated fats, and vegetable oils. These microbes convert FOG into harmless by-products, reducing scum, preventing odor, improving oxygen transfer, and stabilizing the biological process. It is the most sustainable approach to oil and grease removal from wastewater.

Is bioremediation suitable for all hotel wastewater treatment systems?

Yes. Whether your hotel uses a conventional activated sludge process, MBBR, SBR, or a compact STP, bioremediation works safely across all systems. It improves treated-water quality, supports long-term stability, and reduces the load on mechanical cleaning. Most importantly, it tackles the root cause of FOG accumulation making it ideal for wastewater treatment for hotels.

What happens if hotels ignore FOG management in wastewater treatment?

If hotels ignore FOG management, fats and oils slowly accumulate inside pipelines, aeration tanks, and clarifiers. This leads to frequent pipe blockages, foul odors, reduced oxygen transfer, higher BOD/COD levels, and STP breakdowns. Over time, hotels face increased maintenance costs, regulatory penalties, and system downtime. Poor FOG control directly impacts the efficiency and lifespan of hotel wastewater treatment plants.

How does FOG affect aeration efficiency in hotel STPs?

FOG forms floating layers and oily films on the wastewater surface, which prevents proper oxygen transfer from aerators into the water. This reduces microbial activity and slows down biological treatment. As a result, hotels experience low treatment efficiency, higher energy consumption, and unstable STP performance. Effective FOG management restores aeration efficiency and supports healthy biological processes.

What are the signs of FOG-related problems in hotel wastewater systems?

Common signs include excessive scum formation, persistent bad odors, frequent choking of pipelines, foaming in aeration tanks, and inconsistent treated-water quality. Hotels may also notice increased sludge volume and higher power usage in blowers and pumps. These symptoms clearly indicate unmanaged fats, oils, and grease in the wastewater system.

Are grease traps alone enough to control FOG in hotel wastewater?

Grease traps help capture large grease particles at the kitchen level, but they are not enough on their own. Dissolved fats and emulsified oils still pass into the STP, where they cause long-term issues. For complete control, grease traps must be supported with biological treatment that digests residual FOG throughout the wastewater treatment process.

How does proper FOG management support sustainability goals in hotels?

Proper FOG management reduces chemical usage, lowers energy consumption, minimizes sludge generation, and improves treated-water reuse potential. By adopting biological FOG control, hotels align with green building standards, environmental regulations, and sustainability initiatives. It also enhances brand reputation by demonstrating responsible wastewater management practices.