Technical Notes: Grease Problems

ENVIRONMENTAL    “Wastewater Treatment Specialists”                      1728 Trade Drive

PROCESS USA                                                                                 Ruston LA 71270

Cell 318-243-1022

Fax 318-513-1544




(Technical Note No. 1702)


Most municipalities own and operate lift stations or pump stations as part of their sewer collection system.  The biggest problem that exists in sewer collection systems is the accumulation of household and restaurant grease in and on:

  • Lift stations
  • Transfer lines
  • Wet wells
  • Headworks
  • Control floats


Grease adheres to all surfaces especially the inside of pipes where it creates an increase in pumping and maintenance costs.

As grease accumulates inside pipes, it decreases the pipe flow area.  For example, if a six inch-diameter pipe has its flow area reduced to five inches, the pumping cost increases by 250%. The pumping cost increases by over 700% when the flow area of that same pipe is further reduced to four inches.  These data are summarized in the table below and the graph at the end of the article:


Pipe Diameter Increase in Pumping Cost, %
Original – 6”
Reduced to 5” 250
Reduced to 4” 700+


This condition can be controlled by allowing ENVIRONMENTAL PROCESS USA, LLC to service those areas and lift stations that are prone to grease accumulation.  We inject Z-FOG, (Zero Fats, Oils, and Grease), into the lift station or pipe to remove the grease and keep it from adhering to surfaces. We provide the equipment, chemical, and service.

The following describes what happens when Z-FOG is used.


A Nevada sewer collection system had an 18-inch diameter pipe transporting wastewater from restaurants to a lift station. The lift station was producing hydrogen sulfide between 10 and 20 ppm. Normal flow through this pipe was 35,000 gallons per day.  Grease had accumulated such that only about 4,000 gallons per day would flow through the line.

The line was taken out of service and flow re-routed.  The pipe was treated with five gallons of Z-FOG and filled with water.  Eighteen hours after treating with Z-FOG, the line was flushed.  Grease was removed and the line was returned to service at full capacity.


Costly hydro-flushing, snaking, hauling, and disposal were eliminated!



CONDITIONS Wastewater Flow


Hydrogen Sulfide


Before Z-FOG Treatment 4,000 11.5
Normal Flow After Z-FOG Treatment 35,000 0



A sewer district located in south Louisiana recently started treating its collection system.  Within six weeks, the lift station pumping time at the head of two main trunk lines was reduced by 50%.  This translates into huge energy savings. 

We are continuing to collect data on this project and will have a more detailed report soon.


Sewer collection systems and wastewater treatment plants treated with Z-FOG will also be free of FOG related odors. Treatment operators can rest assured that Z-FOG is safe because Z-FOG does not contain:

  • Enzymes
  • Surfactants
  • Emulsifiers
  • Solvents


Furthermore, it is:

  • Non-hazardous
  • Anti-corrosive
  • Bio-degradable
  • Low in toxicity
  • Without regulated impurities


Z-FOG is manufactured according to the EPA’s standards for DfE (Design for the Environment).


The benefits of the grease control program for any municipalities include the following:

  • No startup cost or expensive equipment to purchase.
  • Reduces pumping cost.
  • Reduces maintenance cost.
  • Reduces equipment down time.
  • Reduces odors caused by grease accumulation in lift stations.
  • Eliminates sewer backups due to main line clogging.
  • Allows for the re-allocation of manpower and equipment to areas not presently being served.


Let ENVIRONMENTAL PROCESS USA, LLC make grease problems a NON-ISSUE for your City.


Article written by Donald G. Adams, Ph.D., Senior Environmental Consultant, Environmental Process USA, LLC.  For more information about our services or products, please call 318-243-1022 or 318-224-3348 or email us at