Biological Grease Traps

Biological activators

Unlike strong acid or caustic drain cleaners, ACO biological activator works safely, but more slowly. The biological activator can be used to unblock drains and can be used to replace aggressive caustic and acid cleaners. ACO biological activator works in two distinct ways on the FOG wastes that settle in the drainage pipework and grease trap system:

  • The activator introduces an enzyme that assists the natural biological process of breaking down long molecular chain FOG’s into a manageable solution to then be discharged safely into the drainage system.
  • The activator introduces other micro-organ-isms that actively feed on the FOG’s present in the solution. Biological activators will not digest solid residues from the food preparation process quickly, so the sediment basket requires periodic removal for cleaning to ensure efficient operation. ACO Clear biological activator is available in 5 or 20 litre containers.

ACO activator process

Depending upon the application, space availability and physical layout of the area, grease traps can be installed in parallel to share the hydraulic load as shown below:

FSS Grease Trap Technical data

Product dimensions

Model Ref Part No. A (mm) B (mm) C (mm) D (mm) Dry Weight (kg) Inlet dia (mm) Outlet dia (mm) Meals per day Flow rate l/s
FSS50 402614 610 520 440 185 35 110 110 0-50 2
FSS150 402615 760 660 540 285 48 110 110 50-150 4
FSS250 402616 930 660 540 285 65 110 110 150-250 6

Minimum clear distance above top of grease trap required for service access

Model Ref Total clear height requirement
for grease trap and sediment bucket removal
FSS150 755
FSS150 855
FSS250 855

Drawing:

Accessories:

Grease trap connection accessories

Model Ref Part No. Weight
(kg)
Description
FSS110/50/40 402707 0,9 Stainless steel 110mm to 50mm concentric male / male reducers. Must be ordered two pieces of reducer for one grease trap.
Depending upon installation, flow capacity limitations may be experienced.

 

FSP Grease Trap Technical dat

Product dimensions

Model Ref Part No. A (mm) B (mm) C (mm) D (mm) Dry Weight (Kg) Inlet dia (mm) Outlet dia (mm) Meals

per day

Flow rate l/s
FSP50 49079 610 520 440 205 13 110 110 0-50 2
FSP150 49080 760 660 540 305 21 110 110 50-150 4
FSP250 49081 930 740 540 305 29 110 110 150-250 6

 

Minimum clear distance above top of grease trap required for service access

Model Ref Total clear height requirement for grease trap and sediment bucket removal
FSP150 755
FSP150 945
FSP250 945

 

 

Drawing:

Drawing FSP

 

Accessories:

Grease trap connection accessories

Model Ref Part No. Weight (kg) Description
FSP110/50 402707 0,9 Stainless steel 110mm to 50mm concentric male / male reducers. Must be ordered two pieces of reducer for one grease trap.

Depending upon installation, flow capacity limitations may be experienced.

Dosing System Components

Features and benefits

 

Mains operated dosing unit (MODD) enables maximum operational efficiency of grease management system to be established quickly.

1. Microprocessor controlled dosing is programmed via convenient LCD display touch pad input panel for easy set up and programme modification where, for example, the operating environment changes due to seasonal variations.

2. Water resistant ABS Enclosure conforms to IP 66M for water and dust ingress prevention.

3. Dosing unit delivers 210ml per minute of biological activator, The unit is programmable to match user requirements and supplied complete with PVC tubing, tube connectors and operating instructions.

4. The unit incorporates battery time clock back up in case of power failure.

5. Efficiently allows up to two traps to be dosed by one dosing unit.

6. Precise delivery extends activator economy significantly over “manual dosing” methods.

MODD Mains Operated Drain Dosing Unit

Description Part No. Pump spread
ml/min
Power supply Weight
(kg)
MODD 49025 210 220 / 240 W 1,5
BODD 49024 75 Battery type ‘D’ 1,0

Mounting frame

1. Manufactured in brushed grade 316 stainless steel.
2. Houses 5 litres of activator.
3. Versatile unit can be floor or wall mounted and has reversible door for right hand or left hand opening.
4. Pre-drilled apertures for mains feed and biological activator feed are supplied with blanking grommets.
5. Pre-drilled for wall mounting and dosing unit fixing.

Mounting frame

Description Part No. Weight
(kg)
MF 402637 4,0

Accessories

Biological Activator ACO Clear

1. Available in 5 or 20 litre containers.

2. ACO Clear biological activator introduces an enzyme that assists in breaking down fat, oil and grease deposits. Micro organisms actively feed on fats present in the drainage system or grease trap.

3. The activator can be applied manually, pouring a prescribed amount into the drain directly, or as recommended, via MODD or BODD units.

ACO Clear biological activator

Description Part No. Volume
(l)
Weight
(kg)
ACO Clear 5 litres 49020 5 5
ACO Clear 20 litres 49022 20 20

Operation and Maintenance

Biological dosing regime

Table 1 – dosing times

Meals per
day
ACO Clear
(ml)
Dosing times
Seconds
MODD
50 50 0:14
100 100 1:20
150 150 2:00
200 200 2:40
250 250 3:20
300 300 4:00
350 350 4:40
400 400 5:20
500 500 6:40
600 600 8:00
700 700 9:20
800 800 10:40
900 900 12:00
1000 1000 13:20

Once installed, grease trap performance can be optimised by using the following procedure:

  • Establish total dosing time using table 1 opposite, referring to section “Grease Trap Sizing” to arrive at ‘meals per day’. Then convert the dosing times to seconds for the MODD or dosing unit (Table 1).
  • Establish hourly load on grease trap by considering daily average patterns for all facilities connected to the trap. Table 2 below gives an example of a sixteen hour period with a total capacity of 700 meals per day. Load percentages are shown in row A, row B multiplies load percentage by total dosing time for a MODD unit in order to arrive at the time to be entered into dosing unit programme at the start of that period. For example the unit should be programmed for 30 seconds running at 10am, one minute at 2pm and so on. Programme the unit accordingly.
  • Alternatively, where the load on the grease trap is variable, the dosing can be programmed at the end of the working period, preferably when the trap will not be used for a few hours.

Table 2 – dosing periods

D1 (mm) 7 -10 11 12 13 14 15 -17 18 19 20 21 22 23 Total
Percentage Load 15% 30% 20% 35% 100%
Dosing Time (s) 30 s 60 s 40 s 70 s 200 seconds
Minutes / seconds for programming time
Programming Time (min/s) 0:30 1:00 0:40 1:10 3:20 min/s
  • Shock dosing of the grease trap is an important element to start the biological process. To rapidly establish a biomass within the grease trap, dose the system with 3 or 4 days of maintenance activator to begin the process, either by pouring ACO Clear activator directly through a sink during a quiet period of the working day when there is no drainage activity or by running the dosing pump in priming mode as per the instructions supplied with the pump.

Operation during first 2 weeks

  • Inspect sediment basket daily at first to establish how often the bucket needs to be emptied. If the basket fills rapidly (less than 2 weeks, for example), then it is necessary to provide additional filtration upstream of the trap.

Note: Do not connect macerators to the trap.

  • Inspect the contents of the trap, increasing the dosing frequency and period if:
  • solidified grease is apparent on the surface and/or near the walls of the trap.
  • significant pools of oil are present on the surface
  • flow is impaired at the outlet pipe. This can be established by removing the access point cap.

Ongoing operation

  • Adjust dosing period and frequency for known seasonal variations – establish regular sediment basket removal regime.
  • Drain, clean and inspect the trap twice annually or at more regular intervals if silt build up at the base of the trap exceeds 5cm.

Trouble Shooting

Once ongoing operation is established ACO Biological Grease Traps should provide excellent service. Should problems become apparent, check the following variables.

  • MODD operation, electricity supply and programming.
  • Pipelines from dosing unit.
  • Load on trap in meals per day.
  • Dosing period and frequency.
  • Influent temperature and temperature within trap.