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Passive Grease Traps for Commercial Kitchens

Passive grease traps are designed to intercept fats, oils and grease before they enter the drainage system. As wastewater passes through the unit, FOG separates from the water and is retained within the trap for subsequent removal.

Sometimes referred to as manual grease traps, passive systems operate without the automated grease removal mechanisms found in automatic grease traps. Their straightforward operation can make them a practical option for commercial kitchens where a passive system is suitable for the site’s requirements.

Aqua Mundus supplies passive grease traps in a range of sizes and configurations to suit different commercial kitchen environments.

Passive vs Automatic Grease Traps

The main difference between passive and automatic grease traps is how the captured grease is managed.

A passive grease trap retains separated FOG inside the unit until it is manually removed during cleaning and maintenance. An automatic grease trap incorporates a mechanism that regularly transfers separated grease into a dedicated collection container.

Neither option is automatically right for every kitchen. The appropriate choice depends on factors such as FOG production, wastewater flow, kitchen activity, available space and maintenance requirements.

Aqua Mundus can assess your site for free and recommend whether a passive or automatic grease management system is better suited to your requirements.

Benefits of Passive Grease Traps

Passive grease traps offer several practical benefits for commercial kitchens:

  • Simple operation: passive separation works without an automatic grease removal mechanism.
  • Effective FOG separation: fats, oils and grease are intercepted before wastewater continues into the drainage system.
  • Drainage protection: managing FOG helps reduce grease entering downstream drainage.
  • Range of sizes: different capacities allow the grease trap to be matched to the requirements of the kitchen.
  • Commercial applications: passive systems can be used across a variety of food preparation and commercial kitchen environments.
  • Straightforward maintenance: retained FOG and solids can be removed as part of a planned cleaning and maintenance schedule.

Choosing the Right Passive Grease Trap

Choosing the right passive grease trap involves more than finding a unit that fits the available space. Wastewater flow, connected kitchen equipment, FOG production, capacity and cleaning requirements should all be considered.

An undersized or unsuitable grease trap may require more frequent attention and may not provide the level of grease management your kitchen requires.

Aqua Mundus can help determine the appropriate system for your site. Our team can carry out a free on-site survey to assess your kitchen and drainage requirements before recommending a suitable grease management solution. We also offer a free online grease trap unit size calculator.

We can also provide professional installation and ongoing grease trap cleaning, servicing and repairs to support your system throughout its operational life.

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FAQs

  • What is a passive grease trap?

    A passive grease trap is a system that separates fats, oils and grease from commercial kitchen wastewater without using an automatic grease removal mechanism. Captured FOG remains inside the trap until it is removed during cleaning.

  • How does a passive grease trap work?

    A passive grease trap uses the natural difference in density between water and fats, oils and grease to separate FOG from kitchen wastewater.

    As wastewater enters the trap, its flow slows, allowing lighter fats, oils and grease to rise while heavier food solids settle. The separated FOG remains within the trap while wastewater continues into the drainage system.

    Because the retained grease is not automatically removed, the trap needs to be regularly emptied and cleaned to maintain effective operation.

  • Is a passive grease trap the same as a manual grease trap?

    The terms are sometimes used interchangeably. “Passive grease trap” describes the operating method more accurately because the separation itself occurs passively. However, these systems are sometimes called manual grease traps because accumulated grease and solids need to be manually removed rather than being transferred automatically.

  • How does a passive grease trap separate grease?

    Wastewater is slowed as it enters the trap. Fats, oils and grease are lighter than water and rise towards the surface, while heavier solids can settle. The separated FOG is retained within the trap while wastewater passes onwards into the drainage system.

  • What is the difference between manual and automatic grease traps?

    A manual or passive grease trap stores separated grease within the unit until it is removed during cleaning. An automatic grease trap incorporates a mechanism that removes separated grease from the main chamber and transfers it to a collection container.

  • Do passive grease traps need cleaning?

    Yes. Fats, oils, grease and food solids accumulate within a passive grease trap over time. Regular grease trap cleaning is therefore required to remove this waste and maintain the system.

  • How often should a passive grease trap be cleaned?

    Cleaning frequency depends on the size of the grease trap, the amount of FOG produced and how heavily the kitchen is used. Rather than relying on the same schedule for every site, maintenance requirements should be based on the individual system and operating conditions.

  • What size passive grease trap do I need?

    The correct size depends on factors including wastewater flow, kitchen equipment, FOG production and the demands placed on the system. Aqua Mundus can assess these requirements and recommend an appropriately sized grease trap for your site.
    FREE GREASE TRAP SIZE CALCULATOR

  • Can Aqua Mundus install and maintain passive grease traps?

    Yes. Aqua Mundus can provide support from initial product selection and site assessment through to grease trap installation, cleaning, servicing and repairs.

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