Wastewater Package Plants
The BioTank is at the heart of the Aqua Tech System

The BioTank uses floating and fixed film processes in which microorganisms attach themselves to a  highly permeable media that is submerged in the wastewater. This allows for the absorption of organic and inorganic matter into the slime layer where treatment is realized. Designed properly, this filter is self-purging.


Hydraulic dosing and secondary sludge airlift pump systems are set at pre-determined rates to minimize maintenance and enhance treatment. The self-purging biological filter is designed by Aqua Tech Systems to accommodate influent characteristics and achieve effluent requirements. Oxygen is introduced to the system via an oil-less compressor and membrane aeration equipment.

Wastewater is pumped from the influent pump chamber to mechanical equipment or directly into the first baffled compartment of the BioTank. Alternatively, primarily settled
or prescreened wastewater is pumped from an equalization basin to the BioTank. Wastewater flows by gravity through each treatment compartment of the BioTank and effluent is discharged over a weir.


As flow enters each aerobic compartment dissolved oxygen is transferred to the wastewater via compressor and membrane aeration module. Each compartment has an independent and fully adjustable air regulation valve. In the aerobic modules the
compressor acts as a mixer to enhance treatment and prevent the short-circuiting of wastewater through the plant.

In the BioTank, the organic material in the wastewater is reduced by a population of microorganisms that attach to the filter media and form a biological slime layer. In the outer portion of the slime layer treatment is accomplished by aerobic microorganisms. As the microorganisms multiply the biological film thickens and diffused oxygen is consumed before penetrating the full depth of the slime layer. Consequently the film develops aerobic, anoxic and anaerobic zones.

Absent oxygen and a sufficient external organic source for all cell carbon the microorganisms near the media surface lose their ability to cling to the media. The wastewater flowing over the media washes the slime layer off the media and a new slime layer begins to form. The process of losing the slime layer is called “sloughing” and it is primarily a function of organic and hydraulic loading on the filter. This natural process allows a properly designed media bed to be self-purging and maintenance free.

Any excess sloughed biomass is transferred with the wastewater flow to the final clarifier as sludge. These secondary sludges are periodically pumped back to the primary tank or sludge holding tank for eventual removal or further treatment.

The BioTank treatment plants may also be supplied with bar racks or screens, grit chambers, flow meters, chemical dosing equipment, UV disinfection modules and sludge dewatering systems.

To put the BioTank to work for you, click the button below to schedule a consult.

When we say that our systems are the best, here’s a bit of what we mean.

Major components of the BioTank system are constructed of carbon steel or stainless steel, with plastic or zinc coated steel for railings and fences. The unit provides ready access to each treatment compartment facilitating operation and maintenance procedures. The media blocks are easily removed from each treatment compartment for inspection or plant maintenance.

Random packed media that is biologically inert and mechanically durable enhances oxygen transfer.

The oxygen delivery system comes self-contained within each BioTank.

An efficient oil-less compressor with few moving parts supplies dissolved oxygen to the treatment process. Low noise and vibration is a positive design characteristic associated with these
compressors.

A 304 stainless steel exterior or NEMA 4X mountable control cabinet is provided with each
BioTank. Each cabinet contains the control logic to automate the function of the compressor, sludge airlift, coagulant dosing pump and cabinet heater if necessary.


The BioTank treatment plants can be supplied with separate or attached offices, laboratories and mechanical equipment rooms.

wastewater treatment system inside large building
BioTank installed in a metal building


The BioTank treatment plants may also be supplied with bar racks or screens, grit chambers, flow meters, chemical dosing equipment, UV disinfection modules and sludge dewatering systems.

All of our systems are completely customizable to perfectly fit your needs. Click the button below to speak with a member of our sales team.

Removing ammonia nitrogen from wastewater is a well-established and quantifiable
biological process. Nitrogen exists in the influent primarily in the form of organic nitrogen
and ammonia nitrogen (Total Kejldahl Nitrogen + TKN). The principal part of the organic
nitrogen is mineralized to ammonia nitrogen through bacterial activity. Therefore,
ammonia-N is commonly regarded as the starting point in the nitrogen reduction process.

A diagram of showing the process of ammonium in wastewater being converted to nitrogen gas.
Wastewater nitrification and denitrification take place in our BioTank


Nitrification: the conversion of ammonia nitrogen (NH3-N) to nitrate nitrogen (NO3-N) is a
biological process accomplished in the presence of dissolved oxygen. Typical
requirements for effluent ammonia-N are from 1 to 3 mg/l, which is reliably accomplished.
Successful nitrification is accomplished with a healthy microorganism population and an
environment where PH, temperature, alkalinity, organic loading and dissolved oxygen are
stable.

In the BioTank system the pH is generally buffered by the carbonate system
associated with the wastewater; the temperature remains consistent due to the biological
activity in the plant; the organic loading is relatively constant because the wastewater has
been treated in the first compartment(s) of the plant; and the compressor provides an
adequate supply of dissolved oxygen.

Nitrification/Denitrification Table

Facultative heterotrophic organisms under anoxic conditions accomplish biological
denitrification. In this process bacteria convert the nitrate-N to nitrogen gas
that is released into the atmosphere.


Denitrification occurs by several different means and though process control adjustments.
As the microorganisms multiply, the biological film thickens on the submerged media and
the diffused oxygen is consumed before penetrating the full depth of the slime layer.
Consequently the film develops aerobic, anoxic and anaerobic zones. This process accounts for significant nitrogen removal via simultaneous nitrification and denitrification.

Denitrification utilizing septic tank carbon is widely considered to be the most economical
and efficient method for nitrogen removal. Utilizing prescribed recirculation rates this
method of returning BioTank nitrified wastewater to the carbon source in the anoxic zone
of the primary tank has achieved reductions of nitrogen of approximately 80 percent.


Nitrogen removal may be enhanced further in a tertiary anoxic zone located after the
aerobic treatment.

To learn more about this critical process and how Aqua Tech can help you utilize it, click the button below.

As these media get smaller, their treatment capacity goes up.

Biofilm. It’s not a documentary narrated by David Attenborough; it’s the organic factory that cleans wastewater in our BioTank biological reactors. Biofilm is a population of microorganisms that attach to a filter media and form a biological slime layer. As wastewater flows over the biofilm, the microbes consume the organic material. This means that the more square meters (m2) of biofilm present within a treatment system, the more treatment can take place. Earlier aerobic treatment tanks used suspended growth and fixed film systems which could treat wastewater down to TSS (Total Suspended Solids) and BOD5 (Biological Oxygen Demand) concentrations as low as 20mg/L. Those are impressive numbers compared to traditional onsite system effluent, but those older systems had to be especially large to accommodate a large enough population of microbes to get the job done. Also, treatment was quite slow requiring several days.

But those days are over!

example of a floating biofilm medium
Our treatment systems feature hundreds of these floating media

Aqua Tech’s BioTanks feature one or more* chambers filled with floating biofilm media. These media hold the slime layer rather than allowing the microorganisms to contribute to the suspended solids as with suspended growth systems. Because they move around through the wastewater, they treat more efficiently than fixed film.

How efficiently?

We actually have numbers to answer that question. Remember that when it comes to biofilm, more square meters means more treatment. More square meters per cubic meter (m3) means more treatment in less space – greater efficiency. Our floating media incorporates an incredible amount of surface area per cubic meter. With highly advanced production methods, we can now offer very small media with very high m2/m3 (square meters per cubic meter).

The evolution of floating biofilm media…

Five sizes of wastewater biofilm media
As the media get smaller, the biofilm gets larger.

The photo above shows five generations of floating biofilm media. Let’s look at the m2/m3 for each of them.

This one is a little smaller than a shot glass. It can host 440 square meters of biofilm to every cubic meter of treatment tank.

This one is about the size of a thimble. It’s surface area per cubic meter is over twice the amount of the first one.

This one could fit in a half teaspoon. It’s surface area is 2200 m2/m3.

Now get ready for an evolutionary jump!

Talk about biological engineering. Look at that thing! This little Pringle-shaped wafer boasts 4000 square meters per cubic meter.

It’s this kind of technology that enables Aqua Tech systems to treat down to <10mg TSS & BOD5 within a tiny footprint. And now, with a demand for high efficiency Single Family systems, we’re pushing the boundaries even further.

This little guy is smaller than a nickel. All of those tiny holes translate into a whopping 5000 square meters of biofilm per each cubic meter.

Let us put one of our high tech wastewater treatment systems to work for you today! Just click the button below to get started.


*Number of chambers containing floating media varies by model and application