Arkea® Bioaugmentation & Sludge Management

Arkea® increases oxygen utilization efficiency and accelerates metabolism. The increased endogenous respiration drives reduced yield efficiency and reduces sludge formation.

Case Example 1

Background

The Sturgis, KY wastewater treatment plant is a 0.5 MGD oxidation ditch with (2) final clarifiers. Disinfection is achieved using chlorine.

Customer Problems/Challenges

Customer’s goal was the reduction of high operational costs associated with sludge management, including energy, chemicals, dewatering, transportation, tipping fee, and landfill disposal costs.

ArchaeaSolutions, Inc. Strategy

The City of Sturgis, KY decided to start a process sludge reduction project using Arkea® microbes and process adjustments. ArchaeaSolutions, Inc. personnel added an Arkea® generator. The plant installed a continuous read ORP (oxidation- reduction potential) meter to monitor the oxidation state of the process. The oxidation ditch rotors were hooked to the ORP output and controlled using a variable frequency driver.

Results

The Mixed Liquor Suspended Solids were approximately 4500 mg/l at the start of the project and dropped within 30 days to approximately 500 mg/L before the Arkea® dosage rate of Arkea® was adjusted. The MLSS have been maintained between 1000 – 2000 mg/l. The plant has not wasted or hauled sludge offsite for over two years. The plant staff has adopted the theory of “Treat the wastewater only when it wants to be treated.”

Sludge Yield

Case Example 2

Background

Customer is a northeast WWTP with a 4.0 MGD average and an 8 MGD design flow. The influent primarily consists of domestic wastes. The flow is routed through grit removal to the Orbal oxidation ditch (activated sludge), which was constructed relatively recently. Additional flow (over 4.0 MGD) is directed through the older RBC portion of the treatment plant, which is currently not being used.

The Orbal oxidation ditch has the characteristic of simultaneous nitrification /denitrification in the outer ring where the D.O. level is held at < 0.5 mg/L.

There are two large secondary clarifiers with the potential option of utilizing two additional secondary clarifiers located in the RBC portion of the plant. Sludge is wasted to 8 aerobic digesters of which only 4 were being used at the start of Arkea® treatment.

Customer Problems/Challenges

Customer’s goal was the reduction of high operational costs associated with sludge management, including energy, chemicals, dewatering, transportation, tipping fee, and landfill disposal costs.

ArchaeaSolutions, Inc. Strategy

ArchaeaSolutions, Inc. used Arkea® bioaugmentation and process consulting to reduce sludge yield and improve digester operational efficiency.

Results

Over a 3 year period, the plant has seen a 22.3% reduction in the average sludge yield year to year. This reduction has resulted in a decrease of related operational costs, as well as improved digester operational efficiency, allowing the customer to take 1 of the 4 digesters offline for additional energy savings.

The graphs below show the reduction of the sludge yield even with a significant increase in cBOD loading since Arkea® treatment began.

Understanding the way bacteria affect treatment processes is key to the appropriate Solution.

Let's start with the basics...

Sulfate Reducing Bacteria (or SRB’s) thrive in oxygen deprived environments.  They “feed” on the sulfur in waste, converting it to Hydrogen Sulfide (H2S).  If you don’t recognize the name, you’ll definitely recognize the smell.  Hydrogen Sulfide is one of the culprits behind the unique smell of rotten eggs.  Another is Volatile Fatty Acids (or VFA’s).  VFA’s are produced by another kind of bacteria known as Acid Producing Bacteria (or APB’s) during the fermentation process.  SRB’s also feed on VFA’s.  With a food-rich environment like sewage, ideal for the growth of these odor producing bacteria, how do we limit the unwelcomed odors?

Simple.  Limit the amount of usable bacteria food available.  Basically, we starve them.

With the implementation of ArchaeaSolutions, Inc. BioAugmentation products and practices, our Bacillus bacteria process reduces the Sulfur and VFA’s as a nutrient source without the offensive byproducts, leaving very little for the SRB’s and APB’s to feed on, resulting in, you guessed it, odor control!

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Now we know what causes the smell and how to treat it.  Let’s look at a cause/effect/treatment example…

Cause:  Humans flush toilets.  It’s unavoidable.

Effect:  Everyone’s sewage in one place (collection system).

Treatment:  The introduction of ArchaeaSolutions ProBlend product(s) to existing collection systems to enhance natural breakdown of bacteria “food” sources, furthering sludge management and odor control.