Nebula MultiStage – Less Sludge Means Lower Operating Costs

Less Sludge Lower Costs

Processing, handling and disposal of sludge from biological wastewater treatment processes was something you thought you had to live with. Not any longer.

Nebula™ MultiStage Biofilm Process designed
to reduce sludge production up to 80%

From waste-activated sludge pumping, digestion, thickening and storage to hauling, disposal and filing regulatory paperwork, sludge management is costly. According to the EPA, it represents 40 to 60 percent of the total budget for a wastewater treatment facility.

Managing a mountain of sludge

The large volume of sludge produced in many wastewater treatment plants today is a by-product of suspended growth activated sludge treatment technology. It’s the most common form of biological wastewater treatment in use today, but not necessarily the most efficient.

In this approach, the wastewater is mixed with free-floating microorganisms that gather into biological flocs and are eventually settled out of the wastewater, creating waste activated sludge. A shocking amount of sludge is produced using this treatment method: On average, it generates 0.75 lbs. of solids per 1 lb. of BOD removed. That means a 1 MGD plant with 250 mg/L of BOD influent produces about 1,564 lbs. of sludge per day – or over a half million lbs. of sludge per year!

How to cut the mountain down to size

A different method of biological wastewater treatment can be designed to reduce this mountain of sludge by up to 80%. The Nebula attached growth process from Aquarius Technologies uses proprietary textile media as the home for microorganisms. Oxygen for respiration and mixing of the microbes is provided through a fine bubble diffused aeration system.

Sludge is minimized in the multistage plug flow treatment process by creating different treatment environments with specific microbial populations. Spatial succession of microorganisms creates a food chain, beginning with higher food-to-microorganism ratios in the early stages – lower life forms and lower food-to-microorganism ratios in the later stages – higher life forms.

A dramatic reduction in sludge production

This multistage approach to biological wastewater treatment results in significantly less sludge production: On average, it generates 0.15 lbs. of solids per 1 lb. of BOD removed. To put that into perspective, a 1 MGD plant with 250 mg/L of BOD influent produces about 313 lbs. of sludge per day. That’s an 80% reduction in sludge generation.

Imagine what this dramatic reduction in sludge could mean to your wastewater treatment facility

  • Reduced sludge production
  • Decreased size of sludge facilities
  • Less sludge volume for disposal
  • Significant savings!

An application of the Nebula MultiStage Fixed Biofilm System in southeastern Wisconsin sheds more light on the efficiency of this innovative approach to wastewater treatment:

Prior to installation, this wastewater treatment plant was producing approximately 460,000 gallons per year of waste-activated sludge. After installing the Nebula MultiStage Biofilm System and upgrading the plant’s headworks to include grit removal and fine screening, annual sludge production is now less than 60,000 gallons.

The plant treats wastewater from multiple communities, with an average flow rate of 0.300 million gallons per day (MGD). Five years of operating data produced the following values:

PARAMETER INFLUENT EFFLUENT REMOVAL
BOD (mg/L) 260 5.8 98%
TSS (mg/L) 270 4.0 99%
Ammonia (NH3)-N (mg./L) 25 < 1.0 96%

Learn more about Nebula MultiStage Biofilm System on this website page, or contact us.