BioRemove 4200 significantly improved grease reduction in heavily loaded sewer lines

The application of BioRemove 4200 to heavily loaded sewer lines led to significantly reduced grease deposits.


  • Improved plant efficiency through reduction of grease deposits
  • Simplified operations by providing an easy-to-use solution


A 500 mm (20-inch) gravity sewer line serving a road with a high concentration of restaurants required cleaning as often as every third day to prevent blockages and overflows from sewage backing up in the manholes. Novozymes was contacted for assistance.


Three manholes were treated with BioRemove 4200 in a Novozymes Biosock® over a two-month period and monitored for visual changes in the grease layers and the water depth in the manholes.


Visual changes began to be seen in 3-4 days and a progressive change from thick, crusted, tan grease deposits covering the entire manhole surfaces to thin, light tan deposits covering 50-70% of the manhole surfaces occurred over the next two months. Water levels in these manholes dropped from 20-50 cm (4-20 inches) indicating that grease deposits in the lines between the manholes had also been reduced. No physical cleaning, overflows, or sewer backups occurred during treatment. Figures 1-3 document the visual appearances of the treated manholes during the program.

Fig. 1. Manhole #1 at Start, Day 28 and Day 48

Fig. 2. Manhole #2 at Start, Day 28 and Day 52

Fig. 3. Manhole #3 at Start, Day 28 and Day 35

Temperature can play an important role with collection system applications since biological degradation rates are lower during cold weather months. The water temperature during the application described here was no less than 15°C throughout the trial showing BioRemove excels in reducing grease even at low temperatures.


Novozymes’ biological program was easy to implement and provided significant benefits over other disposal alternatives. BioRemove 4200 resulted in:

  • Lower operating costs
  • Improved plant efficiency
  • Simplified operations